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Adderall

adderall

What is adderall

Adderall contains a combination of amphetamine and dextroamphetamine (brand names Adderall, Adderall XR and Mydayis). Amphetamine and dextroamphetamine are central nervous system stimulants that affect chemicals in the brain and nerves that contribute to hyperactivity and impulse control. It works by changing the amounts of certain natural substances in the brain.

    • Adderall is used to treat narcolepsy and attention deficit hyperactivity disorder (ADHD).
    • Adderall may also be used for purposes not listed in this medication guide.
  • Adderall is used to treat ADHD in adults and children 3 years of age and older.
  • Adderall XR is used to treat ADHD in adults and children 6 years of age and older.
  • Mydayis is used to treat ADHD in adults and children 13 years of age and older.
  • Dextroamphetamine and amphetamine (Adderall) is also used to treat narcolepsy (a sleep disorder that causes excessive daytime sleepiness and sudden attacks of sleep) in adults and children 12 years of age and older.
  • Adderall (amphetamine and dextroamphetamine) is not approved for use by anyone younger than 6 years old.

Adderall Generic name:

DEXTROAMPHETAMINE SACCHARATE 1.25mg, AMPHETAMINE ASPARTATE MONOHYDRATE 1.25mg, DEXTROAMPHETAMINE SULFATE 1.25mg, AMPHETAMINE SULFATE 1.25mg

US Brand Name

  • Adderall
  • Adderall XR

Canadian Brand Name

  • Adderall XR – 10mg
  • Adderall XR – 15mg
  • Adderall XR – 20mg
  • Adderall XR – 25mg
  • Adderall XR – 30mg
  • Adderall XR – 5mg
IMPORTANT WARNING

AMPHETAMINES HAVE A HIGH POTENTIAL FOR ABUSE. ADMINISTRATION OF AMPHETAMINES FOR PROLONGED PERIODS OF TIME MAY LEAD TO DRUG DEPENDENCE AND MUST BE AVOIDED. PARTICULAR ATTENTION SHOULD BE PAID TO THE POSSIBILITY OF SUBJECTS OBTAINING AMPHETAMINES FOR NON-THERAPEUTIC USE OR DISTRIBUTION TO OTHERS, AND THE DRUGS SHOULD BE PRESCRIBED OR DISPENSED SPARINGLY.

MISUSE OF AMPHETAMINE MAY CAUSE SUDDEN DEATH AND SERIOUS CARDIOVASCULAR ADVERSE EVENTS.

  • The combination of dextroamphetamine and amphetamine  (brand names Adderall, Adderall XR and Mydayis) can be habit-forming.

Do NOT take a larger dose, take it more often, or take it for a longer time than prescribed by your doctor. If you take too much dextroamphetamine and amphetamine, you may find that the medication no longer controls your symptoms, you may feel a need to take large amounts of the medication, and you may experience symptoms such as rash, difficulty falling asleep or staying asleep, irritability, hyperactivity, and unusual changes in your personality or behavior. Overusing dextroamphetamine and amphetamine may also cause serious heart problems or sudden death.

Tell your doctor if you or anyone in your family drinks or has ever drunk large amounts of alcohol, uses or has ever used street drugs, or has overused prescription medications. Your doctor will probably not prescribe dextroamphetamine and amphetamine for you.

Do NOT stop taking dextroamphetamine and amphetamine without talking to your doctor, especially if you have overused the medication. Your doctor will probably decrease your dose gradually and monitor you carefully during this time. You may develop severe depression and extreme tiredness if you suddenly stop taking dextroamphetamine and amphetamine after overusing it.

Do NOT sell, give away, share or let anyone else take your medication. Selling or giving away dextroamphetamine and amphetamine may harm others and is against the law. Store dextroamphetamine and amphetamine in a safe place so that no one else can take it accidetally or on purpose. Keep track of how many tablets or capsules are left so you will know if any are missing.

What is Adderall XR (amphetamine and dextroamphetamine) ?

Adderall XR= extended-release Adderall. When taking Adderall XR do not crush, chew, break, or open an extended-release capsule. Swallow it whole.

Amphetamine and dextroamphetamine may be habit-forming, and this medicine is a drug of abuse. Tell your doctor if you have had problems with drug or alcohol abuse.

Stimulants have caused stroke, heart attack, and sudden death in people with high blood pressure, heart disease, or a heart defect.

Do not use this medicine if you have used an MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, or tranylcypromine.

What is Adderall used for

Adderall (amphetamine and dextroamphetamine combination) works in the treatment of attention deficit hyperactivity disorder (ADHD) to increase attention and decrease restlessness in patients who are overactive, cannot concentrate, or are easily distracted. It is used as part of a total treatment program that also includes social, educational, and psychological therapy.

Adderall (amphetamine and dextroamphetamine combination) is available only with a doctor’s prescription. Prescriptions cannot be refilled. A new prescription must be obtained from your doctor each time you need this medicine.

This product is available in the following dosage forms:

Tablet
Capsule, Extended Release (XR)

Proper Use of Adderall

Take Adderall only as directed by your doctor. Do not take more or less of it, do not take it more often and do not take it for a longer time than your doctor ordered. If you take too much, Adderall may become habit-forming (causing mental or physical dependence).

  • Keep track of your medicine. Amphetamine and dextroamphetamine is a drug of abuse and you should be aware if anyone is using your medicine improperly or without a prescription.

Adderall should come with a Medication Guide. Read and follow these instructions carefully. Talk to your doctor if you have any questions.

If you think Adderall is not working properly after you have taken it for several weeks, do not increase the dose and check with your doctor.

Take the Adderall regular tablet in the morning and early afternoon. If you take the Adderall tablet in the evening, you may have trouble falling asleep at night.

If you are using the Adderall XR extended-release capsule:

  • Swallow the capsule whole with water or other liquids. Do not crush, break, or chew it.
  • Take the Adderall XR capsule in the morning. If you take it in the afternoon or evening, you may have trouble falling asleep at night.
  • You may take the Adderall XR capsule with or without food.
  • If you cannot swallow the capsule, carefully open it and sprinkle the small beads over a spoonful of applesauce. Swallow the mixture right away without chewing. Do not store the mixture for future use. Do not crush or chew the beads from the capsule.
  • Avoid drinking fruit juices or taking vitamin C at the same time you take amphetamine and dextroamphetamine. These can make your body absorb less of the medicine.

Before Using Adderall

In deciding to use Adderall, the risks of taking Adderall must be weighed against the good it will do. This is a decision you and your doctor will make. For Adderall, the following should be considered:

  • You may not be able to use Adderall (amphetamine and dextroamphetamine) if you are allergic to any stimulant medicine. You may not be able to use Adderall if you have:
    • high blood pressure, heart disease, coronary artery disease (hardened arteries);
    • overactive thyroid;
    • glaucoma;
    • severe anxiety, tension, or agitation (stimulant medicine can make these symptoms worse); or
    • a history of drug or alcohol addiction.

Some medicines can interact with Adderall (amphetamine and dextroamphetamine) and cause a serious condition called serotonin syndrome. Be sure your doctor knows if you also take opioid medicine, herbal products, or medicine for depression, mental illness, Parkinson’s disease, migraine headaches, serious infections, or prevention of nausea and vomiting. Ask your doctor before making any changes in how or when you take your medications.

Stimulants have caused stroke, heart attack, and sudden death in certain people. Tell your doctor if you have:

  • heart problems or a congenital heart defect;
  • high blood pressure; or
  • a family history of heart disease or sudden death.

To make sure this Adderall (amphetamine and dextroamphetamine) is safe for you, tell your doctor if you or anyone in your family has ever had:

  • depression, mental illness, bipolar disorder, psychosis, or suicidal thoughts or actions;
  • motor tics (muscle twitches) or Tourette’s syndrome;
  • seizures or epilepsy;
  • an abnormal brain wave test (EEG); or
  • blood circulation problems in the hands or feet.

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to Adderall or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of Adderall (amphetamine and dextroamphetamine combination) to treat ADHD in children. However, safety and efficacy have not been established in children younger than 6 years of age (Adderall XR extended-release capsules) or children younger than 3 years of age (tablets).

Geriatric

Appropriate studies on the relationship of age to the effects of Adderall (amphetamine and dextroamphetamine) combination have not been performed in the geriatric population.

Pregnancy

  • Taking Adderall during pregnancy can cause premature birth, low birth weight, or withdrawal symptoms in the newborn baby. Tell your doctor if you are pregnant or plan to become pregnant.
Information about this Adderall (dextroamphetamine-and-amphetamine)-oral-route
Pregnancy CategoryExplanation
All TrimestersCAnimal studies have shown an adverse effect and there are no adequate studies in pregnant women OR no animal studies have been conducted and there are no adequate studies in pregnant women.

Breastfeeding

Studies in women breastfeeding have demonstrated Adderall harmful infant effects. An alternative to Adderall should be prescribed or you should stop breastfeeding while using Adderall.

  • Amphetamine and dextroamphetamine can pass into breast milk and may harm a nursing baby. You should not breast-feed while you are using Adderall.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking Adderall, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using Adderall with any of the following medicines is not recommended. Your doctor may decide not to treat you with Adderall or change some of the other medicines you take.

  • Clorgyline
  • Furazolidone
  • Iproniazid
  • Isocarboxazid*
  • Linezolid*
  • Methylene Blue*
  • Moclobemide
  • Nialamide
  • Pargyline
  • Phenelzine*
  • Procarbazine
  • Rasagiline*
  • Safinamide
  • Selegiline*
  • Sibutramine
  • Toloxatone
  • Tranylcypromine*

*Do not use Adderall if you have used an MAO (monoamine oxidase) inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, or tranylcypromine and others 1.

Using Adderall with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Acetazolamide
  • Benzthiazide
  • Chlorothiazide
  • Chlorpromazine
  • Diazoxide
  • Donepezil
  • Furazolidone
  • Hydrochlorothiazide
  • Hydroflumethiazide
  • Hydroxytryptophan
  • Polythiazide
  • Safinamide
  • Sodium Bicarbonate
  • Trichlormethiazide
  • Xipamide

Using Adderall with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Guanethidine

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Other Medical Problems

The presence of other medical problems may affect the use of Adderall. Make sure you tell your doctor if you have any other medical problems, especially:

  • Agitation, severe or
  • Anxiety, severe or
  • Arteriosclerosis (hardening of the arteries), severe or
  • Coronary artery disease or
  • Drug abuse, history of or
  • Glaucoma or
  • Heart attack, recent or
  • Heart or blood vessel disease (eg, cardiomyopathy), severe or
  • Heart rhythm problems (eg, ventricular arrhythmia) or a family history of or
  • Hypertension (high blood pressure), moderate to severe or
  • Hyperthyroidism (overactive thyroid) or
  • Stroke, history of or
  • Tension, severe or—Should not be used in patients with these conditions.
  • Bipolar disorder (manic-depressive illness), or a family history of or
  • Depression, or a family history of or
  • Mania, history of or
  • Psychosis (mental illness), history of or
  • Raynaud disease or
  • Seizures, history of or
  • Tachycardia (fast heart rate) or
  • Tourette syndrome (tics), or a family history of—Use with caution. May make these conditions worse.

Amphetamine and dextroamphetamine may cause new or worsening psychosis (unusual thoughts or behavior), especially if you have a history of depression, mental illness, or bipolar disorder.

You may not be able to use Adderall if you have glaucoma, overactive thyroid, severe agitation, moderate to severe high blood pressure, heart disease or coronary artery disease, or a history of drug or alcohol addiction.

You may have blood circulation problems that can cause numbness, pain, or discoloration in your fingers or toes.

  • See your doctor right away if you have: signs of heart problems–chest pain, feeling light-headed or short of breath; signs of psychosis–paranoia, aggression, new behavior problems, seeing or hearing things that are not real; signs of circulation problems–unexplained wounds on your fingers or toes.

Adderall side effects

Along with its needed effects, Adderall (amphetamine & dextroamphetamine) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking Adderall (amphetamine & dextroamphetamine) 2, 3:

More common

  • bladder pain
  • bloody or cloudy urine
  • difficult, burning, or painful urination
  • fast, pounding, or irregular heartbeat or pulse
  • frequent urge to urinate
  • lower back or side pain

Less common

  • Cold or flu-like symptoms
  • cough or hoarseness
  • fever or chills

Incidence not known

  • Blistering, peeling, or loosening of the skin
  • chest pain or discomfort
  • confusion
  • dark-colored urine
  • diarrhea
  • difficulty breathing
  • difficulty with speaking
  • difficulty with swallowing
  • dizziness
  • double vision
  • faintness
  • headache
  • inability to move the arms, legs, or facial muscles
  • inability to speak
  • itching, skin rash
  • joint or muscle pain
  • large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • loss of bladder control
  • muscle cramps or spasms
  • muscle pain or stiffness
  • muscle spasm or jerking of all extremities
  • nausea
  • pain or discomfort in the arms, jaw, back, or neck
  • red skin lesions, often with a purple center
  • red, irritated eyes
  • seeing, hearing, or feeling things that are not there
  • seizures
  • slow speech
  • sore throat
  • sores, ulcers, or white spots in the mouth or on the lips
  • sudden loss of consciousness
  • sweating
  • swelling of the feet or lower legs
  • tightness in the chest
  • uncontrolled repeated movements (tics)
  • uncontrolled vocal outbursts
  • unusual tiredness or weakness
  • vomiting

Some side effects of Adderall (amphetamine & dextroamphetamine) may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  • Anxiety
  • dry mouth
  • lack or loss of strength
  • stomach pain
  • weight loss

Incidence not known

  • Constipation
  • decreased interest in sexual intercourse
  • false or unusual sense of well-being
  • inability to have or keep an erection
  • loss in sexual ability, desire, drive, or performance
  • twitching, twisting, uncontrolled repetitive movements of the tongue, lips, face, arms, or legs

Metabolic

Very common (10% or more): Appetite loss (up to 36%), weight loss (up to 10%)
Frequency not reported: Anorexia

Gastrointestinal

Very common (10% or more): Dry mouth (up to 35%), abdominal pain (up to 14%)
Common (1% to 10%): Nausea, vomiting, diarrhea, dyspepsia
Frequency not reported: Unpleasant taste, constipation, other GI disturbances

Cardiovascular

Very common (10% or more): Transient blood pressure elevations (up to 35%)
Common (1% to 10%): Tachycardia, palpitation
Frequency not reported: Cardiomyopathy, myocardial infarction, Raynaud’s phenomenon

Psychiatric

Very common (10% or more): Insomnia (up to 27%), nervousness (up to 13%)
Common (1% to 10%): Emotional lability, agitation, anxiety
Frequency not reported: Psychotic episodes, irritability, euphoria, dysphoria, restlessness, depression, aggression, anger, logorrhea, dermatillomania

Nervous system

Very common (10% or more): Headache (up to 26%)
Common (1% to 10%): Somnolence, dizziness, twitching, speech disorder (e.g., stuttering, excessive speech)
Frequency not reported: Overstimulation, paresthesia/formication, dyskinesia, tremor, exacerbation of motor/phonic tics and Tourette’s syndrome

Dermatologic

Common (1% to 10%): Photosensitivity reaction, sweating
Frequency not reported: Urticaria, rash, alopecia, serious skin rashes (e.g., Stevens-Johnson Syndrome, toxic epidermal necrolysis)

Endocrine

Common (1% to 10%): Decreased libido, dysmenorrhea, impotence
Frequency not reported: Frequent or prolonged erections

Genitourinary

Common (1% to 10%): Urinary tract infection

Other

Common (1% to 10%): Fever, infection, accidental injury, asthenia/fatigue, tooth disorder (e.g., teeth clenching, tooth infection)
Frequency not reported: Sudden death, bruxism

Respiratory

Common (1% to 10%): Dyspnea

Hypersensitivity

Frequency not reported: Hypersensitivity reactions (e.g., angioedema, anaphylaxis)

Ocular

Frequency not reported: Blurred vision, mydriasis

Musculoskeletal

Postmarketing reports: Rhabdomyolysis.

Long term effects of adderall

Over time, the brain gets used to the increased levels of dopamine. When this happens, amphetamine users develop a tolerance to the drug. They have to use more to feel the same highs. That can lead longtime users to have strong cravings for the drug.

When people use large amounts of amphetamines more often, it can put added stress on the heart and lead to elevated blood pressure and pulse rates, rapid breathing, and even heart failure.

Long-term abuse of amphetamines may cause people to have hallucinations, hear voices, feel paranoid, and develop a psychosis that resembles schizophrenia. Long-term amphetamine abusers might become violent or act unpredictably.

Other long-term effects include:

  • physical exhaustion
  • insomnia and restlessness
  • dizziness and blurred vision
  • headaches
  • reduced appetite and health problems from not eating properly
  • higher chances of getting sick because of malnutrition
  • depression, anxiety, and paranoia
  • severe dental problems (“meth mouth”) when using methamphetamine
  • mood disturbances and delusions similar to those felt by people with bipolar disorder or psychosis

Other Possible Problems

Using too large a dose of amphetamines at one time can cause an overdose. Someone who overdoses will have a higher body temperature, hallucinations, convulsions, and could die.

People who use lots of amphetamines can become emotionally dependent on them. These users may become fixated on finding and taking amphetamines. They may do whatever they can to keep getting high, including taking risks.

People whose bodies are used to taking lots of amphetamines might keep using them to avoid withdrawal symptoms. This may lead to binges of drug abuse that can last for days, making the eventual crash even more difficult.

Amphetamines are listed as a Schedule II stimulant, meaning they have a high potential for abuse. Although amphetamines are used in medicines, they are available only through a limited prescription. People who use amphetamines without a prescription could end up in jail.

How Can Someone Quit ?

People who are used to taking large amounts of amphetamines may have a hard time quitting. They may go through various mood problems, such as aggression, anxiety, and intense cravings for the drugs. They also might feel depressed and even have suicidal thoughts when they try to quit.

If you think you might be addicted to amphetamines, talk with a counselor or join a support group. These things can help make it easier to quit.

Avoiding Amphetamines

Unless amphetamines are in powder form, they can look like any other pill. Because people rarely call them “amphetamines,” it can help to be aware of other names for amphetamines, from brand names like Ritalin or Adderall to nicknames like Bennies or Black Mollies.

If someone offers you amphetamines, chances are he or she might not know quite how dangerous they can be. Even when drugs are prescribed by a doctor, that doesn’t make them safe for anyone to take. Protect yourself by being aware of the risks!

Dosing of Adderall

The dose of this medicine will be different for different patients. Follow your doctor’s orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

For oral dosage form (extended-release capsules):
For ADHD:
Adults—20 milligrams (mg) once a day in the morning. Your doctor may adjust your dose if needed.
Teenagers 13 to 17 years of age—At first, 10 mg once a day in the morning. Your doctor may adjust your dose if needed.
Children 6 to 12 years of age—At first, 10 mg once a day in the morning. Your doctor may adjust your dose if needed. However, the dose is usually not more than 30 mg per day.
Children younger than 6 years of age—Use and dose must be determined by your doctor.
For oral dosage form (tablets):
For ADHD:
Adults and children 6 years of age and older—At first, 5 milligrams (mg) given one or two times a day. Your doctor may adjust your dose if needed.
Children 3 to 5 years of age—At first, 2.5 mg once a day. Your doctor may adjust your dose if needed.
Children younger than 3 years of age—Use is not recommended.
For narcolepsy:
Adults and children 12 years of age and older—At first, 10 milligrams (mg) per day, divided and given in 2 doses. Your doctor may adjust your dose if needed.
Children 6 to 12 years of age—At first, 5 mg per day. Your doctor may adjust your dose if needed.
Children younger than 6 years of age—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of Adderall, take it as soon as possible, but not late in the day. Skip the missed dose if it is almost evening. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses and do not take extra medicine to make up the missed dose.

What happens in Adderall overdose ?

Seek emergency medical attention, call your local emergency number.

An overdose of amphetamine and dextroamphetamine could be fatal.

Overdose symptoms may include:

  • restlessness,
  • tremor,
  • muscle twitches,
  • rapid breathing,
  • confusion,
  • hallucinations,
  • panic,
  • aggressiveness,
  • muscle pain or weakness, and
  • dark colored urine.

These symptoms may be followed by depression and tiredness. Other overdose symptoms include nausea, vomiting, diarrhea, stomach pain, uneven heartbeats, feeling light-headed, fainting, seizure (convulsions), or coma.

Storage

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
  • Keep out of the reach of children.
  • Do not keep outdated medicine or medicine no longer needed.
  • Ask your healthcare professional how you should dispose of any medicine you do not use.

Adderall Dosage

Regardless of indication, amphetamines should be administered at the lowest effective dosage, and dosage should be individually adjusted according to the therapeutic needs and response of the patient. Late evening doses should be avoided because of the resulting insomnia.

Attention Deficit Hyperactivity Disorder

Not recommended for children under 3 years of age. In children from 3 to 5 years of age, start with 2.5 mg daily; daily dosage may be raised in increments of 2.5 mg at weekly intervals until optimal response is obtained.

Age 3 to 5 Years:
-Initial Dose: 2.5 mg orally per day
-Maintenance Dose: Daily dose may be raised in 2.5 mg increments at weekly intervals until optimal response is obtained.

Age 6 to 17 Years:
-Initial Dose: 5 mg orally 1 or 2 times a day
-Maintenance Dose: Daily dose may be raised in 5 mg increments at weekly intervals until optimal response is obtained.
-Maximum Dose: Only in rare cases will it be necessary to exceed 40 mg per day.

In children 6 years of age and older, start with 5 mg once or twice daily; daily dosage may be raised in increments of 5 mg at weekly intervals until optimal response is obtained. Only in rare cases will it be necessary to exceed a total of 40 mg per day. Give first dose on awakening; additional doses (1 or 2) at intervals of 4 to 6 hours.

Where possible, drug administration should be interrupted occasionally to determine if there is a recurrence of behavioral symptoms sufficient to require continued therapy.

Adderall XR:

Age 6 to 12 Years (starting treatment for the first time or switching from another medication):
-Initial Dose: 5 or 10 mg orally once a day in the morning
-Maintenance Dose: Daily dose may be raised in 5 to 10 mg increments at weekly intervals.
-Maximum Dose: 30 mg/day

Age 13 to 17 Years (starting treatment for the first time or switching from another medication):
-Initial Dose: 10 mg orally once a day
-Maintenance Dose: Daily dose may be increased to 20 mg/day after one week if symptoms are not adequately controlled.
-Maximum Dose: 30 mg/day

Adult Patients starting treatment for the first time or switching from another medication:
-Initial Dose: 20 mg orally once a day

Narcolepsy

Usual dose 5 mg to 60 mg per day in divided doses, depending on the individual patient response.

Narcolepsy seldom occurs in children under 12 years of age; however, when it does, dextroamphetamine sulfate may be used. The suggested initial dose for patients aged 6 to 12 is 5 mg daily; daily dose may be raised in increments of 5 mg at weekly intervals until optimal response is obtained. In patients 12 years of age and older, start with 10 mg daily; daily dosage may be raised in increments of 10 mg at weekly intervals until optimal response is obtained. If bothersome adverse reactions appear (e.g., insomnia or anorexia), dosage should be reduced. Give first dose on awakening; additional doses (1 or 2) at intervals of 4 to 6 hours.

Ritalin vs adderall

Ritalin (methylphenidate) is a central nervous system stimulant 4. It affects chemicals in the brain and nerves that contribute to hyperactivity and impulse control. Ritalin is used to treat attention deficit disorder (ADD), attention deficit hyperactivity disorder (ADHD), and narcolepsy. Ritalin may also be used for purposes not listed here.

Important information

You should not use Ritalin if you have glaucoma, tics or Tourette’s syndrome, or severe anxiety, tension, or agitation.

Methylphenidate may be habit-forming, and this medicine is a drug of abuse. Tell your doctor if you have had problems with drug or alcohol abuse.

Stimulants have caused stroke, heart attack, and sudden death in people with high blood pressure, heart disease, or a heart defect.

Do not use Ritalin if you have used an MAO inhibitor in the past 14 days, such as isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, or tranylcypromine.

Methylphenidate may cause new or worsening psychosis (unusual thoughts or behavior), especially if you have a history of depression, mental illness, or bipolar disorder.

You may have blood circulation problems that can cause numbness, pain, or discoloration in your fingers or toes.

See your doctor right away if you have: signs of heart problems – chest pain, feeling light-headed or short of breath; signs of psychosis – paranoia, aggression, new behavior problems, seeing or hearing things that are not real; signs of circulation problems – unexplained wounds on your fingers or toes.

This medicine should come with a Medication Guide. Read and follow these instructions carefully. Ask your doctor if you have any questions. Ask your pharmacist for the Medication Guide if you do not have one.

To help prevent trouble with sleeping, take the last dose of the short-acting tablets before 6 PM, unless your doctor gives you a different time.

If you are taking the chewable tablet, drink at least 8 ounces of water or other liquid when you chew the tablet. Take it preferably 30 to 45 minutes before meals.

Shake the oral liquid gently just before using it. Use a marked measuring spoon, oral syringe, or medicine cup to measure the right dose. Take it preferably 30 to 45 minutes before meals.

If you are taking the long-acting forms of Methylphenidate:

  • The Concerta® extended release tablets, Aptensio XR™, Metadate CD®, or Ritalin LA® capsules, and Ritalin SR® tablets are to be swallowed whole with water or other liquids. Do not break, open, crush, or chew them before swallowing.
  • If you are unable to swallow the Aptensio XR™, Metadate CD®, or Ritalin LA® extended-release capsule whole, carefully open the capsule and sprinkle the small beads over a spoonful of applesauce. The mixture of drug and applesauce should be taken right away without chewing. The drug and applesauce mixture should not be stored for future use.
  • If you are taking the Concerta® extended-release tablets, you may sometimes notice what looks like a tablet in your stool. This is the empty tablet shell that is left after the medicine has been absorbed into your body.
  • You may take Concerta® extended release tablets or Aptensio XR™ capsules with or without food.
  • If you are taking the Quillivant™ XR extended-release suspension, shake the bottle well for at least 10 seconds before measuring each dose. Use only the oral dosing dispenser provided in the package to get the right dose. You may take it with or without food.
  • If you are taking the Quillichew ER™ tablets, you may cut the 20- and 30-milligram (mg) scored chewable tablets into two if needed.

Dosing of Ritalin

The dose of this medicine will be different for different patients. Follow your doctor’s orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

For attention deficit hyperactivity disorder (ADHD):

  • For short-acting oral dosage forms (chewable tablets or solution):
    • Adults—Administer 2 or 3 times a day and take 30 to 45 minutes before meals. The average dose is 20 to 30 milligrams (mg) per day. Your doctor may adjust your dose as needed. However, the dose is usually not more than 60 mg per day.
    • Children 6 years and older—At first, 5 mg 2 times a day, taken before breakfast and lunch. Your doctor may adjust your dose as needed. However, the dose is usually not more than 60 mg per day.
    • Children younger than 6 years—Use and dose must be determined by the doctor.
  • For short-acting oral dosage form (tablets):
    • Adults—5 to 20 milligrams (mg) 2 or 3 times a day, taken 30 to 45 minutes before meals.
    • Children 6 years and older—At first, 5 mg two times a day, taken before breakfast and lunch. Your doctor may adjust your dose as needed. However, the dose is usually not more than 60 mg per day.
    • Children younger than 6 years—Use and dose must be determined by the doctor.
  • For long-acting oral dosage form (extended-release capsules):
    • Patients who have not been treated with methylphenidate:
      • Adults and children 6 years and older—At first, 10 to 20 milligrams (mg) once a day, taken in the morning. Your doctor may adjust your dose as needed. However, the dose is usually not more than 60 mg per day.
      • Children younger than 6 years—Use and dose must be determined by the doctor.
    • Patients who are already taking methylphenidate:
      • Adults and children 6 years and older—10 to 60 milligrams (mg) once a day, taken in the morning. Your doctor may adjust your dose as needed. However, the dose is usually not more than 60 mg per day.
      • Children younger than 6 years—Use and dose must be determined by the doctor.
  • For long-acting oral dosage form (extended-release suspension):
    • Adults and children 6 years and older—At first, 20 milligrams (mg) once a day, taken in the morning. Your doctor may adjust your dose as needed. However, the dose is usually not more than 60 mg per day.
    • Children younger than 6 years—Use and dose must be determined by the doctor.
  • For long-acting oral dosage form (extended-release chewable tablets):
    • Adults and children 6 years and older—At first, 20 milligrams (mg) once a day, taken in the morning. Your doctor may adjust your dose as needed. However, the dose is usually not more than 60 mg per day.
    • Children younger than 6 years—Use and dose must be determined by the doctor.
  • For long-acting oral dosage form (extended-release tablets):
    • For patients who have not been treated with Concerta®:
      • Adults—At first, 18 to 36 milligrams (mg) once a day in the morning. Your doctor may adjust your dose as needed. However, the dose is usually not more than 72 mg per day.
      • Children 6 years and older—At first, 18 mg once a day in the morning. Your doctor may adjust your dose as needed. However, the dose is usually not more than 72 mg per day.
      • Children younger than 6 years—Use and dose must be determined by your doctor.
    • For patients already using Concerta®:
      • Adults and children 6 years and older—At first, 18 to 72 milligrams (mg) once a day in the morning. Your doctor may adjust your dose as needed. However, the dose is usually not more than 72 mg per day.
      • Children younger than 6 years—Use and dose must be determined by your doctor.

For narcolepsy:

  • For short-acting oral dosage forms (chewable tablets or solution):
    • Adults—Administer 2 or 3 times a day and take 30 to 45 minutes before meals. Average dose is 20 to 30 milligrams (mg) per day. Your doctor may adjust your dose as needed. However, the dose is usually not more than 60 mg per day.
    • Children 6 years and older—At first, 5 mg 2 times a day, taken before breakfast and lunch. Your doctor may adjust your dose as needed. However, the dose is usually not more than 60 mg per day.
    • Children younger than 6 years—Use and dose must be determined by the doctor.
  • For short-acting oral dosage form (tablets):
    • Adults—5 to 20 milligrams (mg) 2 or 3 times a day, taken 30 to 45 minutes before meals.
    • Children 6 years and older—At first, 5 mg 2 times a day, taken before breakfast and lunch. Your doctor may adjust your dose as needed. However, the dose is usually not more than 60 mg per day.
    • Children younger than 6 years—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

For the extended-release suspension: Throw away any unused suspension 4 months after it is used for the first time.

Precautions

Your doctor should check your or your child’s progress at regular visits to make sure this medicine is working properly and to decide if you should continue to take it. Blood tests may be needed to check for unwanted effects.

You or your child will also need to have your blood pressure and heart rate measured before starting this medicine and while you are using it. If you notice any change in your blood pressure, call your doctor right away. If you have questions about this, talk to your doctor.

You or your child should not use this medicine if you have used a drug for depression called an MAO inhibitor (MAOI), such as Eldepryl®, Marplan®, Nardil®, or Parnate®, in the past 14 days.

Methylphenidate may cause dizziness, drowsiness, or changes in vision. Do not drive a car, ride a bicycle, operate machinery, or do other things that might be dangerous until you know how this medicine affects you.

Methylphenidate may cause serious heart or blood vessel problems. This may be more likely in patients who have a family history of heart disease. Check with your doctor right away if you or your child has chest pain, shortness of breath, fainting, or a fast, irregular heartbeat while using this medicine.

Tell your doctor right away if you or your family notice any unusual changes in behavior, such as an increase in aggression, hostility, agitation, irritability, or suicidal thinking or behaviors. Also tell your doctor if you have hallucinations or any unusual thoughts, especially if they are new or getting worse quickly.

This medicine may cause slow growth. If your child is using this medicine, the doctor will need to keep track of his height and weight to make sure that he is growing properly.

Methylphenidate may cause a condition called Raynaud phenomenon. Check with your doctor right away if you or your child has tingling or pain in the fingers or toes when exposed to cold, paleness or a cold feeling in the fingertips and toes, or a skin color change in your fingers.

Make sure any doctor or dentist who treats you knows that you are using Metadate CD®. You may need to stop using this medicine before you have surgery.

Avoid drinking alcohol while taking the Aptensio XR™, Metadate CD®, Quillichew ER™ tablets, or Ritalin LA® extended-release capsules.

If you or your child experience a prolonged or painful erection of the penis for more than 4 hours, check with your doctor right away.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines, herbal or vitamin supplements, and medicine for appetite control, asthma, colds, cough, hayfever, or sinus problems.

Ritalin Side Effects

Along with its needed effects, methylphenidate (the active ingredient contained in Ritalin) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking methylphenidate 5, 6, 7, 8, 9, 10, 11:

More common

  • Fast heartbeat

Less common

  • Chest pain
  • fever
  • joint pain
  • skin rash or hives

Rare

  • Black, tarry stools
  • blood in the urine or stools
  • blurred vision or other changes in vision
  • crusting, dryness, or flaking of the skin
  • muscle cramps
  • pinpoint red spots on the skin
  • scaling, severe redness, soreness, or swelling of the skin
  • seizures
  • uncontrolled vocal outbursts or tics (uncontrolled and repeated body movements)
  • unusual bleeding or bruising

Incidence not known

  • Confusion
  • depression
  • feeling like surroundings are not real
  • numbness of the hands
  • painful or difficult urination
  • pale skin
  • paleness or cold feeling in the fingertips and toes
  • red, irritated eyes
  • red, swollen, or scaly skin
  • seeing, hearing, or feeling things that are not there
  • severe or sudden headache
  • sores, ulcers, or white spots on the lips or in the mouth
  • sudden loss of coordination
  • sudden slurring of speech
  • tingling or pain in the fingers or toes when exposed to cold
  • unusual behavior
  • unusual tiredness or weakness
  • weight loss
  • yellow skin or eyes

Get emergency help immediately if any of the following symptoms of overdose occur while taking methylphenidate:

Symptoms of overdose

  • Agitation
  • anxiety
  • bigger, dilated, or enlarged pupils of the eyes
  • confusion as to time, place, or person
  • dark-colored urine
  • diarrhea
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • dry eyes, mouth, nose, or throat
  • false or unusual sense of well-being
  • fast, slow, irregular, pounding, or racing heartbeat or pulse
  • holding false beliefs that cannot be changed by fact
  • increased sensitivity of the eyes to light
  • loss of consciousness
  • muscle pain or stiffness
  • muscle twitching
  • nervousness
  • overactive reflexes
  • pounding in the ears
  • rapid, shallow breathing
  • sweating
  • tremors
  • unusual excitement, nervousness, or restlessness

Some side effects of methylphenidate may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  • Headache
  • loss of appetite
  • nervousness
  • stomach pain
  • stuffy nose
  • trouble sleeping
  • unusually warm skin

Less common

  • Anger
  • decreased appetite
  • dizziness
  • drowsiness
  • fear
  • irritability
  • muscle aches
  • nausea
  • runny nose
  • scalp hair loss
  • talking, feeling, and acting with excitement
  • vomiting

General

In children, the following adverse reactions may occur more frequently: loss of appetite, abdominal pain, weight loss during prolonged therapy, insomnia, and tachycardia.

Other

  • Very common (10% or more): Infections and infestations (45.2%)
  • Common (1% to 10%): Lethargy, ear infection, pyrexia, fatigue, ear and labyrinth disorders, reproductive system and breast disorders, growth retardation (reduced weight and height gain), thirst, asthenia, influenza, erectile dysfunction, injury/poisoning/procedural complications
  • Uncommon (0.1% to 1%): Chest pain
  • Rare (less than 0.1%): Gynecomastia
  • Frequency not reported: Increased erection, prolonged erection, chest discomfort, hyperpyrexia, abuse and dependence
  • Postmarketing reports: Priapism

Psychiatric

  • Very common (10% or more): Psychiatric disorders (27.9%), insomnia (13.3%), irritability (11%)
  • Common (1% to 10%): Anxiety, restlessness, sleep disorder, agitation, affect lability, aggression, depression, depressed mood, abnormal behavior, bruxism, confusional state, initial insomnia, decreased libido, nervousness, emotional poverty, tension, panic attack
  • Uncommon (0.1% to 1%): Psychotic disorders, hallucinations (auditory, visual, tactile), anger, suicidal ideation, altered mood, mood swings, tearfulness, tics, worsening of pre-existing tics or Tourette’s syndrome, hypervigilance
  • Rare (less than 0.1%): Mania, disorientation, libido disorder
  • Very rare (less than 0.01%): Suicidal attempt/completed suicide, transient depressed mood, abnormal thinking, apathy, repetitive behaviors, over-focusing
  • Frequency not reported: Delusions, thought disturbances, confessional state, logorrhea

Metabolic

  • Very common (10% or more): Decreased appetite (27.1%), metabolism and nutrition disorders (11.5%)
  • Common (1% to 10%): Anorexia, decreased weight

Gastrointestinal

  • Very common (10% or more): Gastrointestinal disorders (23.5%), dry mouth (21.5%), nausea (12.2%), vomiting (10.2%)
  • Common (1% to 10%): Abdominal pain (upper and general), diarrhea, dyspepsia, toothache, stomach discomfort
  • Uncommon (0.1% to 1%): Constipation

Nervous system

  • Very common (10% or more): Nervous system disorders (23.5%), headache (23.2%)
  • Common (1% to 10%): Dizziness, dyskinesia, tremor, drowsiness, feeling jittery, psychomotor hyperactivity, somnolence, vertigo, paresthesia, motion sickness, tension headache
  • Uncommon (0.1% to 1%): Sedation, tremor
  • Very rare (less than 0.01%): Convulsions, choreoathetoid movements, reversible ischemic neurological deficit, cerebrovascular disorders (vasculitis, cerebral hemorrhages, cerebrovascular accidents, cerebral arteritis, cerebral occlusion), neuroleptic malignant syndrome (NMS)
  • Frequency not reported: Grand mal convulsions, migraine, sedation

Respiratory

  • Very common (10% or more): Nasopharyngitis (19.1%), respiratory/thoracic/mediastinal disorders (10.6%)
  • Common (1% to 10%): Upper respiratory tract infection, cough, oropharyngeal/pharyngolaryngeal pain, sinusitis, dyspnea

Musculoskeletal

Very common (10% or more): Musculoskeletal and connective tissue disorders (14.4%),
Common (1% to 10%): Joint sprain, arthralgia
Uncommon (0.1% to 1%): Myalgia, muscle twitching, muscle tightness, muscle spasms
Very rare (less than 0.01%): Muscle cramps
Frequency not reported: Rhabdomyolysis

Local

Very common (10% or more): Administration site and general disorders (12.9%)
Postmarketing reports: Patch application site reactions

Cardiovascular

Common (1% to 10%): Palpitations, tachycardia, cardiac disorders, vascular disorders, arrhythmias, hypertension, hot flush, changes in blood pressure and heart rate (usually an increase)
Uncommon (0.1% to 1%): Cardiac murmur
Rare (less than 0.1%): Angina pectoris
Very rare (less than 0.01%): Cardiac arrest, myocardial infarction, peripheral coldness, Raynaud’s phenomenon, sudden cardiac death
Frequency not reported: Supraventricular tachycardia, bradycardia, ventricular extrasystoles, extrasystoles

Dermatologic

Common (1% to 10%): Rash, pruritus, urticaria, fever, scalp hair loss/alopecia, dermatitis, excoriation hyperhidrosis, skin and subcutaneous tissue disorders
Uncommon (0.1% to 1%): Angioneurotic edema, bullous conditions, exfoliative conditions
Rare (less than 0.1%): Macular rash, erythema
Very rare (less than 0.01%): Thrombocytopenic purpura, exfoliative dermatitis, erythema multiforme, fixed drug eruption

Immunologic

Common (1% to 10%): Immune systems disorders

Ocular

Common (1% to 10%): Eye disorders, eye pain
Uncommon (0.1% to 1%): Diplopia, blurred vision
Rare (less than 0.1%): Visual accommodation difficulties, mydriasis, visual disturbance
Frequency not reported: Dry eye
Postmarketing reports: Visual impairment[Ref]

Genitourinary

Uncommon (0.1% to 1%): Hematuria, pollakiuria

Hepatic

Uncommon (0.1% to 1%): Hepatic enzyme elevations
Very rare (less than 0.01%): Abnormal liver function, hepatic coma, increased blood alkaline phosphatase, increased blood bilirubin
Postmarketing reports: Hepatocellular injury, acute hepatic failure

Hypersensitivity

Uncommon (0.1% to 1%): Hypersensitivity reactions (angioedema, anaphylaxis, auricular swelling, exanthemas)

Hematologic

Very rare (less than 0.01%): Leukopenia, thrombocytopenia, anemia, decreased platelet count, abnormal white blood count
Postmarketing reports: Pancytopenia

Concerta vs adderall

Concerta is a brand name of a drug containing the same methylphenidate as Ritalin. See Ritalin above for details.

Methylphenidate US Brand Names:

  • Aptensio XR
  • Concerta
  • Metadate CD
  • Metadate ER
  • Methylin
  • Methylin ER
  • QuilliChew ER
  • Quillivant XR
  • Ritalin
  • Ritalin LA
  • Ritalin-SR

Adderall alternatives

There are two main kinds of ADHD medications: stimulants and non-stimulants.

  1. Stimulants include Concerta, Ritalin LA, Focalin XR, Metadate CD, Daytrana, Adderall, and Vyvanse. They come as a liquid, pill, capsule, and even a patch. Stimulants work very quickly, and people with ADHD may see an improvement right away.
  2. Non-stimulants work a little differently in the brain than stimulants. They may take longer to work, but they work better than stimulants for some people. Non-stimulants include atomoxetine (Strattera), extended release guanfacine (Intuniv), extended release clonidine (Kapvay), and certain antidepressants (such as Wellbutrin).

Doctors work closely with people who have ADHD to figure out which medicine will be most helpful. Because everyone’s different, doctors might try a couple of medicines before finding the one that works best.

Some teens need a combination of medicines. They might need both a stimulant and a non-stimulant at the same time to get the best results.

References
  1. Adderall XR. https://www.drugs.com/mtm/adderall-xr.html
  2. “Product Information. Adderall (amphetamine-dextroamphetamine)” Shire Richwood Pharmaceutical Company, Florence, KY.
  3. “Product Information. Adderall XR (amphetamine-dextroamphetamine).” Shire Richwood Pharmaceutical Company Inc, Florence, KY.
  4. Ritalin. https://www.drugs.com/ritalin.html
  5. “Product Information. Metadate CD Capsules (methylphenidate)” Celltech Pharmaceuticals, Inc, Applegate, WI.
  6. “Product Information. Quillivant XR (methylphenidate).” NextWave Pharmaceuticals , Vernon Hills, IL.
  7. “Product Information. Metadate ER (methylphenidate).” Celltech Pharmacueticals Inc, Appleton, WI.
  8. “Product Information. Concerta (methylphenidate).” Alza, Palo Alto, CA.
  9. Cerner Multum, Inc. “UK Summary of Product Characteristics.”
  10. Cerner Multum, Inc. “Australian Product Information.”
  11. “Product Information. Ritalin (methylphenidate).” Novartis Pharmaceuticals, East Hanover, NJ.
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DrugsDrugs & Supplements

General anesthesia

general anesthesia

What is general anesthesia

General anesthesia is treatment with certain medicines that make you are completely unconscious and unable to feel pain during medical procedures or surgery. General anesthesia is more than just being asleep; the anesthetized brain doesn’t respond to pain signals or reflexes. After you receive these medicines, you will not be aware of what is happening around you.

General anesthesia include analgesia (relief from or prevention of pain), paralysis (muscle relaxation), amnesia (loss of memory), or unconsciousness. General anesthesia usually uses a combination of intravenous drugs and inhaled gasses (anesthetics). A patient under the effects of anesthetic drugs is referred to as being anesthetized.

An anesthesiologist is a specially trained doctor who specializes in anesthesia. While you’re unconscious, the anesthesiologist monitors your body’s vital functions and manages your breathing.

In many hospitals, an anesthesiologist and a certified registered nurse anesthetist work together during your procedure.

The purpose of general anesthesia can be distilled down to three basic goals or end points:

  1. Hypnosis (a temporary loss of consciousness and with it a loss of memory). In a pharmacological context, the word hypnosis usually has this technical meaning, in contrast to its more familiar lay or psychological meaning of an altered state of consciousness not necessarily caused by drugs.
  2. Analgesia (block pain sensation which also blunts autonomic reflexes)
  3. Muscle relaxation

The ideal general anesthetic drug would provide hypnosis, amnesia, analgesia, and muscle relaxation without undesirable changes in blood pressure, pulse or breathing.

Anesthesia enables the painless performance of medical procedures that would cause severe or intolerable pain to an unanesthetized patient.

How does general anesthesia work

General anesthesia suppresses central nervous system activity and results in unconsciousness, complete muscle paralysis and total lack of sensation 1. The goal is to make and keep a person completely unconscious (or “asleep”) during the operation, with no awareness or memory of the surgery. General anesthesia can be given through an IV (which requires sticking a needle into a vein, usually in the arm) or by inhaling gases or vapors by breathing into a mask or tube. General anesthesia delivered intravenously will act quickly and disappear rapidly from the body. This allows patients to go home sooner after surgery. Inhaled anesthetics may take longer to wear off.

Surgeons use general anesthesia when they operate on internal organs and for other invasive or time-consuming procedures such as back surgery. Without general anesthesia, many major, life-saving procedures would not be possible, including open-heart surgery, brain surgery and organ transplants.

General anesthetics typically are very safe. But they can pose risks for some patients, such as the elderly or people with chronic illnesses such as diabetes. Also, side effects may linger for several days in some patients, especially the elderly and children.

Before Surgery

Although you may be able to talk to the anesthesiologist a day or two prior to the operation, you might not meet until that day. Either way, the anesthesiologist will go over your medical history and information thoroughly, so that he or she can make the right choice regarding anesthetic medications tailored to your individual needs.

To ensure your safety during the surgery, you’ll need to answer all of the anesthesiologist’s questions as honestly and thoroughly as possible. Things that may seem harmless could interact with or affect the anesthesia and how you react to it.

The anesthesiologist might order additional tests (such as X-rays or blood or laboratory tests) to help figure out the best possible personalized anesthetic plan for you.

In addition to doing a physical examination of your airways, heart, and lungs, the anesthesiologist will also want to get your medical history, which will include asking about:

  • your current and past health
  • your family’s health
  • any medications, supplements, or herbal remedies you are taking (consider bringing a list of exactly what you take, detailing how much and how often)
  • any previous reactions you or any blood relative has had to anesthesia
  • any allergies (especially to foods, medications, or latex) you may have
  • whether you smoke, drink alcohol, or take recreational drugs.

This will help your anesthesiologist choose the medications that will be the safest for you.

How you prepare for a general anesthesia

General anesthesia relaxes the muscles in your digestive tract and airway that keep food and acid from passing from your stomach into your lungs. Always follow your doctor’s instructions about avoiding food and drink before surgery.

Fasting is usually necessary starting about six hours before your surgery. You may be able to drink clear fluids until a few hours prior.

Your doctor may tell you to take some of your regular medications with a small sip of water during your fasting time. Discuss your medications with your doctor.

You may need to avoid some medications, such as aspirin and some other over-the-counter blood thinners, for at least a week before your procedure. These medications may cause complications during surgery.

Some vitamins and herbal remedies, such as ginseng, garlic, Ginkgo biloba, St. John’s wort, kava and others, may cause complications during surgery. Discuss the types of dietary supplements you take with your doctor before your surgery.

If you have diabetes, talk with your doctor about any changes to your medications during the fasting period. Usually you won’t take oral diabetes medication the morning of your surgery. If you take insulin, your doctor may recommend a reduced dose.

If you have sleep apnea, discuss your condition with your doctor. The anesthesiologist or anesthetist will need to carefully monitor your breathing during and after your surgery.

Eating and Drinking Before Anesthesia

The anesthesiologist, surgeon, or someone on the nursing staff will give you instructions about not eating or drinking before surgery. It’s important to make sure you don’t eat anything prior to surgery (usually nothing after midnight the day before the operation). You’ll get specific instructions based on your age, medical condition, and the time of day of the procedure.

Why is eating before surgery an issue? Because the body normally has reflexes that prevent food from being aspirated (or inhaled) into the lungs when it’s swallowed or regurgitated (thrown up). But anesthetic medications can suspend these reflexes, which could cause food to become inhaled into the lungs if there is vomiting or regurgitation under anesthesia.

Sometimes, though, the anesthesiologist will say it’s OK to drink clear liquids or take specific medications a few hours before surgery.

In the Operating Room

If general anesthesia is used, the anesthesiologist will start transitioning you from the normal awake state to the sleepy state of anesthesia. This is called induction, which is usually done by either injecting medicine through an IV or by inhaling gases through a mask.

If, like lots of people, you’re afraid of needles, the good news is that you may not have to get one while awake. Anesthesiologists often will begin the induction process by using a breathing mask to help you relax. The mask delivers medication to make you sleepy before and during the surgery. That way, you won’t be awake when the IV is inserted for general anesthesia or when a shot is given to numb a certain part or area of the body for local or regional anesthesia.

When using general anesthesia, the anesthesiologist will monitor your vital signs, continue to deliver anesthesia, and keep you as comfortable as possible throughout the operation.

To help you breathe and/or to help deliver general anesthesia during the operation, the anesthesiologist might use an endotracheal tube (a plastic tube that’s placed into the windpipe through the mouth or nose) or laryngeal mask airway (or LMA — a mask with a tube that fits into the back of the mouth).

During the procedure

Your anesthesiologist usually delivers the anesthesia medications through an intravenous line in your arm. Sometimes you may be given a gas that you breathe from a mask. Children may prefer to go to sleep with a mask.

Once you’re asleep, the anesthesiologist may insert a tube into your mouth and down your windpipe. The tube ensures that you get enough oxygen and protects your lungs from blood or other fluids, such as stomach fluids. You’ll be given muscle relaxants before doctors insert the tube to relax the muscles in your windpipe.

Your doctor may use other options, such as a laryngeal airway mask, to help manage your breathing during surgery.

Someone from the anesthesia care team monitors you continuously while you sleep. He or she will adjust your medications, breathing, temperature, fluids and blood pressure as needed. Any issues that occur during the surgery are corrected with additional medications, fluids and, sometimes, blood transfusions.

Blood transfusions may sometimes be necessary, such as during complex surgeries. The anesthesia care team monitors your condition and delivers blood transfusions when needed. Blood transfusions may involve risks. These risks are greater in people who are older, have low red blood cell volume or are undergoing complex heart surgeries.

After Surgery

Once the operation or procedure is over, you’ll be taken to the recovery room or PACU (post-anesthesia care unit). In the PACU, nurses and the anesthesiologist will monitor your condition very closely to make sure you are making a smooth and comfortable transition from an anesthetized state to an awakened state.

If you had general anesthesia or were sedated, don’t expect to be fully awake right away — it may take a while and you may doze off for a bit. It usually takes about 45 minutes to an hour to recover completely from general anesthesia. In some cases, this period may be a bit longer depending on medications given during or after surgery.

Although every person has a different experience, you may feel groggy, confused, chilly, nauseated, scared, alarmed, or even sad as you wake up. Depending on the procedure or surgery, you may also have some pain and discomfort afterward, which the anesthesiologist can relieve with medications. When you have recovered from the anesthesia, you’ll be evaluated to make sure you’re ready to leave the recovery room.

In many outpatient procedures, people are allowed to come home soon after the surgery is done. Before you leave the hospital, you’ll receive instructions for further recuperation at home and for a follow-up visit with the surgeon. Talk to the surgeon and/or the anesthesiologist about what to expect after the surgery and how you can stay as comfortable as possible.

Anesthesia is very safe. In today’s hospitals and surgery centers, highly trained professionals use a wide variety of modern medications and extremely capable monitoring technology to ensure that people are stable and as comfortable as possible before, during, and after their procedure.

After the procedure

When the surgery is complete, the anesthesia medications are stopped, and you slowly wake either in the operating room or the recovery room. You’ll probably feel groggy and a little confused when you first wake. You may experience common side effects such as:

  • Nausea
  • Vomiting
  • Dry mouth
  • Sore throat
  • Shivering
  • Sleepiness
  • Mild hoarseness

You may also experience other side effects after you awaken from anesthesia, such as pain. Side effects depend on your individual condition and the type of surgery. Your doctor may give you medications after your procedure to reduce pain and nausea.

During your anaesthetic

Induction (“going off to sleep”)

Your anaesthetist may start your anaesthetic or induce ‘sleep’ in one of three ways. Induction may be:

  • Intravenous (into the vein): the most common method
  • Inhalation (by breathing in) sometimes called “gas induction”: often used in children
  • Intramuscular (into the muscle) injection: now used very rarely.

Intravenous induction

Before having an intravenous induction, you may have had local anaesthetic cream applied to the skin over the vein to be used for the initial injection. The location of the vein depends on the anaesthetist’s preference, the site of the operation, and the appearance of your veins. Often the veins on the back of the hand or forearm are used. The choice of hand depends on whether you are left- or right-handed, because having a bruise on the back of your dominant hand may cause discomfort afterwards. Also, if your intravenous line must remain in place for some time, you will find it easier to be able to do things, such as combing your hair or brushing your teeth, if your intravenous is not in the hand with which you normally do these things.

Having wiped away the cream and applied some cleaning alcohol to the skin, your anaesthetist inserts a cannula or fine plastic tube into the vein. This is accompanied by a sensation varying between slight pain and a feeling of light pressure. In the absence of local anaesthetic cream, you feel a short sharp pain. The cannula is secured to the skin with tape and may be attached to an intravenous ‘line’ or long clear plastic tube connected to a bag of saline or similar fluid. This fluid may feel cold when it runs into the vein (usually in your arm).

Your anaesthetist may then have you breathe oxygen from a mask. This process is known as preoxygenation. Your anaesthetist may also give you one or more drugs, before giving you the actual drug which makes you lose consciousness. For example, if you are scheduled to have your gallbladder removed, your anaesthetist might start by giving you an injection of a drug to relax you, and then a drug to decrease the chance of postoperative vomiting. You might also be given an injection of a potent painkiller (opiate or narcotic), such as fentanyl. This drug also helps minimise any marked rises in heart rate and blood pressure that can occur at a slightly later stage of the anaesthetic and operation. Sometimes anaesthetists give these additional drugs after you have lost consciousness.

The anaesthetist then injects the induction drug through the cannula into your vein. This is the time when he or she may ask you to count (often backwards, from 100). Counting is a means of distracting you and also shows when the drug has achieved its effect. The induction drug works very quickly, especially in younger patients. It takes only the time for the blood carrying the drug to return from the arm to the heart and then be pumped through the lungs, back to the heart, and then to the brain. (Anaesthetists call this the ‘arm-brain circulation time’.) In most people this time is about ten seconds, but it may be faster in children and slower in elderly or very ill patients.

Inhalation (gas) induction

This method is common in children but is also used in some adults. It involves having the anaesthetist or the patient hold a mask over the patient’s nose and mouth. The patient then breathes in a mixture of gases through the face mask until loss of consciousness occurs. Induction by mask usually takes longer than the intravenous method, and achievement of the appropriate depth of anaesthesia is often preceded by a period of restlessness. This is quite normal and the patient is already unconscious at this time.

Then the anaesthetist has an assistant (nurse, technician or another anaesthetist) hold the mask and ensures that the patient is continuing to breathe well. The anaesthetist then inserts an intravenous cannula (as above), unless one has previously been started. This is more likely to have been done in adults. From this point, the anaesthetic is similar, whether an intravenous or inhalation technique has been used.

What happens once you are asleep ?

After the induction drug has caused you to lose consciousness, your anaesthetist gives you one or more other drugs (a mixture of painkillers, sedatives, and anaesthetic gases) to ensure that you remain unconscious. If these other anaesthetic agents were not given, you would regain consciousness in a few minutes, after the induction drug had worn off.

Breathing during anaesthesia

Once you are unconscious, your anaesthetist will take over the management of your breathing, while attending to any changes in your pulse, blood pressure and the amount of oxygen in the blood. This management might consist of holding the mask over your mouth and nose, ensuring that you are breathing clearly and without snoring; or holding the mask and breathing for you by squeezing a bag attached to the breathing circuit; or inserting a breathing tube into your mouth.

Throughout the operation you are given oxygen, first with the mask, and then usually through a plastic airway. There are several types of airway, each of which is a different size, depending on your age and size. The presence of an airway helps to ensure that your breathing is adequate and, in the case of an endotracheal (breathing) tube, that acid from your stomach does not pass into your lungs.

Muscle relaxation

To help manage your breathing, your anaesthetist might inject a muscle relaxant, to relax or weaken your throat and abdominal muscles. Muscle relaxants have two major useful effects.

  • They make it easier for your anaesthetist to insert a breathing (endotracheal) tube through your mouth or, on occasion, through your nose, into your trachea or windpipe. (This process is known as tracheal intubation.) Without muscle relaxants, your anaesthetist would have to give higher doses of other drugs so as to weaken the muscles of your mouth and throat, to make insertion of the tube ( intubation) easier.
  • They actually make it possible for the surgeon to perform many operations, without causing any damage to muscle fibres. Indeed, it is difficult for a surgeon to operate inside your abdomen if the muscles are not relaxed. The same applies to other operations, such as those on the hip or in the chest, but not for those on the skin or the body surface.

If you have been given a muscle relaxant, all of your muscles will be relaxed or weakened, including the muscles that help with breathing. In that case, your anaesthetist ‘breathes for you’. This is usually done with a ventilator, which pushes gas around the anaesthetic circuit and into your lungs. Ventilation may also be done by hand, with your anaesthetist squeezing a bag attached to the anaesthetic circuit.

Airways and breathing tubes

The smallest airway is the oral airway. An average adult airway is about ten centimetres in length and one centimetre in diameter and is curved to fit over the back of the tongue. An oral airway is most often used for minor operations, such as those on a limb, particularly if the duration of the procedure is to be short. The laryngeal mask airway is longer and fits over the top of the larynx. Many anaesthetists now use the laryngeal mask for cases for that would previously have had an oral airway and for cases that may have required an endotracheal tube.

The endotracheal tube is long enough to reach from just outside your mouth or nose and down to just below your vocal cords. The decision to use an endotracheal tube is determined by your condition, the operation to be performed, and the position in which you are placed during the operation. Usually, an endotracheal tube is used if the surgeon is to operate on the brain, the head and neck region, the chest, the back, the abdomen, or the pelvis. Although the anaesthetic is started while you are lying on your back, your surgeon may need you to be in a different position for the operation. For example, if you are to have an operation on your back, the Operating Room team will turn you over onto your stomach after you are unconscious and an endotracheal tube has been inserted.

An airway is placed in your mouth after you become unconscious, although rarely an endotracheal tube must be inserted before any drugs are given and you are still conscious. This is known as ‘awake intubation’ and is only likely if you have a tumour or severe obstruction in your throat.

Awake intubation

Before placement of an endotracheal tube while still conscious, you would be given a solution of local anaesthesia to gargle, which numbs your mouth and throat, and decreases any gagging or coughing as the tube is inserted. Your anaesthetist would explain the process beforehand.

If your anaesthetist has chosen to use a laryngeal mask or endotracheal tube, it is connected to the circuit after it has been inserted. Your anaesthetist controls and monitors the flow and concentration of gases that enter and leave the circuit and your body, so that you receive the appropriate amount of anaesthetic and breathe adequately.

How does your anaesthetist know that the tube is where it should be ?

If the anaesthetist has inserted an endotracheal tube into your trachea (windpipe), you breathe carbon dioxide out through the tube. (Carbon dioxide is the gas produced by the body as it uses oxygen to generate energy. Carbon dioxide is then excreted from the body through the lungs.) Carbon dioxide can be measured with a specific monitor, normally attached to the endotracheal tube. The presence of carbon dioxide in the endotracheal tube suggests that the tube is in your trachea.

There are other methods to help confirm the correct position of the tube, but they are less accurate than the carbon dioxide monitor. Your anaesthetist might also use a stethoscope to listen for the sounds of air moving in and out of your lungs on both sides of your chest and carefully observe how your chest moves up and down with each breath, noting whether or not this movement is symmetrical, which usually occurs when the tube is in the trachea.

Your anaesthetist might also listen to your chest to ensure that the tracheal tube has not been placed too far down into one lung. This is known as an endobronchial intubation and is sometimes done on purpose. If the surgeon wants to operate on the left lung, then the tube is intentionally placed into the right lung.

Induction of anaesthesia in children

Children vary greatly in the way they react to induction of anaesthesia. All children exhibit fear in some way, because of the strange environment, separation from their parents, and the uncertainty about what is to happen to them.

Less than six months

Infants of less than six months do not react strongly to being separated from their parents and usually respond appropriately to a parent substitute. The anaesthetist should be accustomed to caring for small children and, together with other staff, be empathetic with both child and parents.

It is uncommon for parents to accompany infants of less than six months during induction of anaesthesia. This is for two reasons: a child of this age does not suffer major separation anxiety; and everything occurs much more quickly in a baby. This includes the action of drugs and the need to act to correct problems such as breath holding. The anaesthetist must devote his or her whole attention to the child without also having to be concerned about parents.

Six months to four years

Children in this age group do not tolerate separation from their parents well and are not able to comprehend explanation. They react to the unknown with fear, withdrawal and struggling. Induction of anaesthesia is best performed either with a parent present, or premedication, or both. With a parent present, the child tends to cling. Induction of anaesthesia can be difficult in this age group. Adequately sedated, there is little problem and usually no recollection of events. However, the sedative drugs may prolong the recovery phase and delay discharge from hospitals after minor or day stay operations.

With a parent present, either an intravenous or inhalation (gas) induction may be used. For intravenous induction, the parent is asked to hold the child firmly, with the parent either sitting on a chair or leaning over the child who is in a cot or on a bed. The parent is then asked to interact with the child by talking, singing or playing with a toy. At the same time, an assistant secures an arm or a leg where local anaesthetic cream has been applied, while the anaesthetist inserts a cannula.

Inhalation induction is preferred by some anaesthetists. However, usually a mask cannot be placed over a child’s face without a struggle. Sometimes this struggle may be minimised by the anaesthetist applying a few drops of a common food flavouring, such as strawberry, orange or bubblegum, to the mask. These scents help to disguise the smell of the anaesthetic gases. Alternatively, some anaesthetists use their hand as a mask. Induction by mask takes longer than intravenous induction.

Four to six years

Children in this age group are still anxious about separation but are more accepting of explanations and reassurance. As with younger children, they benefit from having a parent present during induction, although less physical restraint is required.

Six to ten years

Children aged six to ten years have less of a problem with separation from parents and are much more amenable to reassurance. They do, however, fear anaesthesia and surgery, and particularly pain. They may have fantasies of mutilation and require reassurance about the exact nature of the operation. They will be irritable and impatient.

Intravenous induction is usually well tolerated, although the fear of needles may be so strong that even application of local anaesthetic cream is not enough to overcome the fear. Cooperation can usually be obtained for an inhalation induction with a mask. Sometimes a child indicates a preference, especially if he or she has had previous anaesthetics.

The presence of a parent or guardian can be of great assistance to the child and the anaesthetist.

Adolescents

This group of patients may fear loss of control and death. It is important to reassure them of the safety of modern anaesthesia and that they can be in control of their pain management after the operation.

Intravenous induction is commonly used in adolescents. However, some patients request an inhalation induction, particularly if they have undergone several (or multiple) operations.

Your role as a parent during induction of anaesthesia

You can be an enormous help during induction of your child’s anaesthetic. Your presence, in most cases, means a calmer, more cooperative patient, with less likelihood of bad memories of the hospitalization.

There are several points to consider. Just as your child needs to be prepared for the event, so you need to learn as much as you can about what will happen.

Part of your preparation includes recognising that you, too, may be distressed by the experience. The final decision rests with the anaesthetist as to your presence. Although many anaesthetists are now used to having parents present at induction, some find their presence stressful. For the child’s safety, an anaesthetist may prefer not to have this added distraction.

Your presence may not be encouraged in every situation. This applies particularly if your child needs an emergency operation. Should something happen, such as your child vomiting, then the anaesthetist needs to focus attention on the child.

You should not feel pressured to be involved. Not everyone is comfortable with the idea of staying during induction and you are free to decline the invitation.

You should be prepared for your child’s appearance after induction. Your child will become anaesthetised within seconds and may suddenly look lifeless, but often with the eyes still open. This is normal. At the same time the anaesthetist will be concentrating on the next step in the process of caring for your child. He or she usually cannot talk with you or to answer questions at that time.

You should go when asked to leave.

Emergency induction of general anaesthesia

Your anaesthetist might modify the induction of anaesthesia by using a technique known as a rapid sequence induction’. This is a crucial technique in patients who must undergo an emergency operation and who have a full stomach, either because they have just eaten or because their stomachs take longer than normal to empty (as a result of pain, drugs, or other conditions).

In a rapid sequence induction, you are given 100 per cent oxygen to breathe from a mask placed firmly over your mouth and nose for three to four minutes. This process is known as preoxygenation and replaces the nitrogen in your lungs (the most common gas in the air) with oxygen. As a result, the store of oxygen in your body is markedly increased and there is less chance of lack of oxygen ( hypoxia).

In the next step your anaesthetist calculates the dose of two drugs – the induction drug (usually propofol or pentothal) and a rapid-acting muscle relaxant. The dose of each drug is calculated on the basis of your weight and your general condition.

Your anaesthetist then injects the two drugs rapidly through the intravenous cannula and you quickly lose consciousness. This minimises any risk of your going through a stage during the loss of consciousness when you struggle or vomit.

As you lose consciousness, your anaesthetist instructs an assistant to apply firm pressure to the front of your neck. The assistant normally stands on your right and uses the first three fingers of the right hand to apply the pressure. (You might feel the assistant’s fingers lightly touching your neck as you lose consciousness.) The specific part where the pressure is applied, called your cricoid cartilage, is a ring of cartilage that forms part of your trachea. Pressure on the cricoid cartilage ( cricoid pressure) seals off the oesophagus and reduces the possibility of stomach contents flowing from the oesophagus into the back of the throat and then down into the lungs.

Maintenance of anaesthesia (“keeping you asleep”)

During the maintenance phase of the anaesthetic, your anaesthetist keeps you in a state of unconsciousness, using a mixture of inhaled (inhalational) and intravenous (injected) drugs. The inhalational agents are administered through the breathing circuit. They include nitrous oxide and the ‘volatile’ anaesthetic agents (because they pass easily from being a liquid to a gas). The volatile anaesthetic agents are commonly used in proportions between 0.5 and 4 per cent, although this varies according to the agent and the desired effect. They are powerful drugs and are used to keep you unconscious, as well as helping to control pain and to relax muscles. These drugs can also have side effects, such as low blood pressure, changes in heart rhythm, and difficulties with breathing.

Nitrous oxide (N2O) or (‘laughing gas’) is used in many general anaesthetics, in a mixture with oxygen of around 70 per cent nitrous oxide and 30per cent oxygen. At that concentration the nitrous oxide may make you sleepy and able to tolerate mildly painful procedures, but that is all. Nitrous oxide does, however, provide a means of giving other stronger anaesthetic gases through the breathing system.

Air, enriched with extra oxygen, is sometimes used when nitrous oxide is less desirable, such as during anaesthesia in the elderly, for some brain surgery, some major heart and lung surgery, and in some tiny premature infants.

During most anaesthetics, oxygen is added so that the usual proportion given to the patient is about 30 per cent. This extra oxygen provides some safety margin over the normal 21 per cent in room air. The critical aspect of anaesthesia care is to ensure that you continue to receive adequate oxygen, which is necessary for preservation of life and the functioning of organs.

Your anaesthetist may choose to give you other drugs through the intravenous line. Depending on the drug, your anaesthetist may do this to increase the depth of the anaesthetic (how unconscious you are). Drugs are also given to provide pain relief after the operation. If the surgeon needs your muscles to be relaxed (in order to perform the procedure), your anaesthetist may give you further doses of the muscle relaxant drug given at the time of induction, or a different drug. Intravenously administered drugs may be given in separate or discrete doses (sometimes known as ‘bolus’ doses) or by constant injection or ‘infusion’ regulated by a pump.

Sometimes your anaesthetist will not use any inhalation anaesthetics at all. When all anaesthetic drugs are given intravenously, it is referred to as Total Intravenous Anaesthesia, or TIVA. These drugs are usually given by carefully controlled infusion.

Emergence (“waking up”)

The third phase of the general anaesthetic is emergence or regaining consciousness. During this phase your anaesthetist stops giving you all inhalational anaesthetic agents (except the oxygen) and also stops any intravenous anaesthetic drugs. You gradually regain consciousness. Your anaesthetist usually needs to reverse the effects of the muscle relaxants, with the injection of two more drugs. As consciousness returns, your anaesthetist makes sure that you can breathe without help. Once you are regaining consciousness and able to breathe without any help from the anaesthetist, the breathing tube is removed. By carefully calculating the right amounts of each drug, your anaesthetist can ensure that you are completely unconscious during the operation, but awake and pain-free at the end of the procedure.

General anesthesia drugs

A general anesthetic (or anaesthetic) is a drug that can bring about a reversible loss of consciousness. Anesthesiologist (or anaesthetist) administers these drugs to induce or maintain general anesthesia to facilitate surgery. Some of these drugs are also used in lower dosages for pain management. The biological mechanisms of the action of general anesthetics are not well understood.

Mode of administration. Drugs given to induce general anesthesia can be either as gases or vapors (inhalational anesthetics) or as injections (intravenous anesthetics or even intramuscular). It is possible to deliver anesthesia solely by inhalation or injection, but most commonly the two forms are combined, with an injection given to induce anesthesia and a gas used to maintain it.

There are four main types of medications used in general anesthesia:

  1. Induction medications to produce unconsciousness
  2. Analgesics to provide pain relief
  3. Muscle relaxants to induce muscle relaxation
  4. Inhalational anesthetics to keep you unconscious.

Other medications which are given include:

  • medications that produce short-term memory loss or amnesia
  • medications that minimize nausea and vomiting (anti-emetics)
  • medications that counter-act the effect of other medications (antagonists)
  • and medications that suppress certain nervous reflexes, such as slowing of the heart.

Also, some patients may not have a general anesthetic but may remain conscious, with part of their body made numb by the use of local anesthetics.

Induction medications

These medications include thiopentone or pentothal (which was introduced in the 1930s), and propofol. When given by intravenous injection, these medications quickly make you unconscious. This rapid loss of consciousness makes the induction of anesthesia much more pleasant than previously, when patients had to breathe ether or chloroform.

Analgesics

These medications, also known as painkillers, are mostly opiates or narcotics. They are either derived from the opium poppy (such as morphine) or are synthesized in a laboratory (such as pethidine or meperidine, anileridine, fentanyl, alfentanil, sufentanil, and remifentanil).

Muscle relaxants

These medications work specifically to weaken or relax most of the (voluntary) muscles of the body. However, they do not affect the muscles of the heart, nor those of the intestines. Before muscle relaxants were introduced in the 1940s, patients had to be given large amounts of anesthetic medications to ensure that they were deeply anesthetized. This was necessary to cause their muscles to relax so that the surgeon could operate within the abdomen, or perform other delicate surgery. Now, with the use of muscle relaxants, patients do not have to receive very large amounts of anesthetic medications nor be so deeply anaesthetized. This helps to reduce the side-effects of anesthesia. Muscle relaxants include suxamethonium (or succinyl choline), pancuronium, atracurium, vecuronium, and rocuronium.

Inhalation general anesthetic

These medications keep you unconsciousness during the operation. They can also be used to induce anaesthesia, especially in small children. These medications are called inhalational agents because you inhale them or breathe them in. In the 1950s, a new inhalational agent, halothane, was introduced and rapidly replaced the older agents such as ether. Halothane has now been largely superseded by even better inhalation medications, and the commonly used agents include enflurane, isoflurane, sevoflurane, and desflurane.

Inhalational anaesthetic substances are either volatile liquids or gases, and are usually delivered using an anesthesia machine. An anesthesia machine allows composing a mixture of oxygen, anesthetics and ambient air, delivering it to the patient and monitoring patient and machine parameters. Liquid anesthetics are vaporized in the machine. All of these agents share the property of being quite hydrophobic (i.e., as liquids, they are not freely miscible—or mixable—in water, and as gases they dissolve in oils better than in water).

Many compounds have been used for inhalation anaesthesia, but only a few are still in widespread use.

  • Enflurane, desflurane, isoflurane and sevoflurane are the most widely used volatile anaesthetics today.

They are often combined with nitrous oxide. Older, less popular, volatile anaesthetics, include halothane, enflurane, and methoxyflurane. Researchers are also actively exploring the use of xenon as an anaesthetic.

Injection general anesthetic

Injectable general anesthetics are used for the induction and maintenance of a state of unconsciousness. Anaesthetists prefer to use intravenous injections, as they are faster, generally less painful and more reliable than intramuscular or subcutaneous injections.

Among the most widely used drugs are:

  • Propofol
  • Etomidate
  • Barbiturates such as methohexital and thiopentone/thiopental
  • Benzodiazepines such as midazolam
  • Ketamine is used in the UK as “field anaesthesia”, for instance at a road traffic incidents or similar situations where an operation must be conducted at the scene or when there is not enough time to move to an operating room, while preferring other anaesthetics where conditions allow their use. It is more frequently used in the operative setting in the US.

Benzodiazepines are sedatives and are used in combinations with other general anesthetics.

Anti-emetics

These medications help reduce nausea and vomiting and so are termed anti-nauseants or anti-emetics. They include droperidol, Stemetil, Gravol, and ondansetron.

Other medications

Your anaesthetist may use other medications to decrease the chance of you remembering anything that happens in the Operating Room. These medications include diazepam and midazolam, which belong to the class of medications known as benzodiazepines. Some medications are given to counteract the effects of other medications. These include naloxone, to counter the effects of an opiate or narcotic; flumazenil, to counter the effects of a benzodiazepine; and neostigmine, to reverse the actions of most of the muscle relaxants. Medications which are used to change your heart rate include atropine (to increase it) and esmolol (to decrease it). Other medications can raise your blood pressure (epinephrine or adrenaline) or lower it (nitroprusside).

Local anesthetics

Injection of a local anaesthetic around a nerve or a group of nerves temporarily blocks the transmission of the electrical impulses in the nerve. The lack of transmission causes the area of the body supplied by the nerve to become numb. This is also known as a ‘sensory block’, which may progress to muscle weakness, depending on the concentration and dose of the local anaesthetic used.

How does your anaesthetist know how much to give you ?

Individuals vary in their requirements for anaesthetic drugs. The dose of the induction drug is generally given slowly to patients who are to have an elective operation. Your anaesthetist has calculated the expected dose you should need, from your weight, your age, your sex, and your state of health. However, as the drugs are injected, the dose of each is adjusted as necessary, according to the effects produced. This is known as titrating the drugs according to their effect. In an emergency it is sometimes necessary to give the drugs quickly, and a predetermined dose is calculated.

Will you have the same anaesthetic as the patient in the bed next to you ?

Every anaesthetic given is a very individual thing and each anaesthetic depends on the patient to whom it is given. The doses of drugs that you are given are calculated according to your weight, age and state of health; the operation or examination for which it is given; and even the anaesthetist who gives them. There is no fixed recipe.

General anesthesia risks

General anesthesia today is very safe. In very rare cases, general anesthesia can cause complications (such as strange heart rhythms, breathing problems, allergic reactions to medications, and even death). The likelihood of a complication occurring is proportional to a variety of factors related to the patient’s health, the kind of procedure (complexity of the surgery being performed) and the type of anesthesia used. Be sure to talk to your doctor, surgeon, and/or anesthesiologist about any concerns.

Most complications can be prevented by giving the anesthesiologist complete information before the surgery about things like:

  • your current and past health (including diseases or conditions such as recent or current colds, or other issues such as snoring or depression)
  • any medications (prescription and over-the-counter), supplements, or herbal remedies you are taking
  • any allergies (especially to foods, medications, or latex) you may have
  • whether you smoke, drink alcohol, or take any recreational drugs
  • any previous reactions you or any family member has had to anesthesia

To ensure your safety during the surgery or procedure, it’s extremely important to answer all of the anesthesiologist’s questions as honestly and thoroughly as possible. Things that may seem harmless could affect how you react to the anesthesia.

It’s also important that you follow the doctor’s recommendations about what not to do before the surgery. You probably won’t be able to eat or drink (usually nothing after midnight the day before) and may need to stop taking herbal supplements or other medications for a certain period of time before surgery.

You can rest assured that the safety of anesthetic procedures has improved a lot over the years, thanks to advances in technology and the extensive training anesthesiologists receive. The more informed, calm, and reassured you are about the surgery and the safety of anesthesia, the easier the experience will probably be.

General anesthesia side effects

General anesthesia is overall very safe; most people, even those with significant health conditions, are able to undergo general anesthesia itself without serious problems.

General anesthetics side effects—such as dangerously low blood pressure—are much less common than they once were. Still, as with any medical procedure, some risks exist. To minimize these risks, specialized doctors called anesthesiologists carefully monitor unconscious patients and can adjust the amount of anesthetic the patients receive.

In fact, your risk of complications is more closely related to the type of procedure you’re undergoing and your general physical health, rather than to the type of anesthesia.

Older adults, or those with serious medical problems, particularly those undergoing more extensive procedures, may be at increased risk of postoperative confusion, pneumonia, or even stroke and heart attack.

Specific conditions that can increase your risk of complications during surgery include:

  • Smoking
  • Seizures
  • Obstructive sleep apnea
  • Obesity
  • High blood pressure
  • Diabetes
  • Other medical conditions involving your heart, lungs or kidneys
  • Medications, such as aspirin, that can increase bleeding
  • History of heavy alcohol use
  • Drug allergies
  • History of adverse reactions to anesthesia

These risks are generally related to the surgery itself, not the anesthesia.

Common Side Effects of General Anesthesia

You will most likely feel disoriented, groggy, and a little confused when waking up after surgery. Some other common side effects, which should go away fairly quickly, include:

  • feeling sick and vomiting – this usually occurs immediately, although some people may continue to feel sick for up to a day
  • shivering and feeling cold – this may last a few minutes or hours
  • confusion and memory loss – this is more common in elderly people or those with existing memory problems; it’s usually temporary, but occasionally can be longer lasting
  • bladder problems – you may have difficulty passing urine
  • dizziness – you will be given fluids to treat this
  • bruising and soreness – this may develop in the area where you were injected or had a drip fitted; it usually heals without treatment
  • sore throat – during your operation, a tube may be inserted either into your mouth or down your throat to help you breathe; afterwards, this can cause a sore throat
  • damage to the mouth or teeth – a small proportion of people may have small cuts to their lips or tongue from the tube, and some may have damage to their teeth; you should tell your anaesthetist about any dental work you have had done

A number of more serious complications are associated with general anaesthetics, but these are rare.

Possible serious complications and risks include:

  • a serious allergic reaction to the anaesthetic (anaphylaxis)
  • waking up during your operation – the amount of anaesthetic given will be continuously monitored to help ensure this doesn’t happen
  • death – this is very rare, occurring in around 1 in every 100,000 cases

Serious problems are more likely to occur if you’re having major or emergency surgery, you have any other illnesses, you smoke, or you’re overweight.

Your anaesthetist will discuss the risks with you before your operation. You should try to stop smoking or drinking alcohol in the weeks before surgery, as doing so will reduce your risk of developing complications.

You may also be advised to lose weight, and if you can you should increase your activity levels in the weeks before surgery, as this is likely to reduce your risk as well.

In most cases, the benefits of being pain-free during an operation outweigh the risks.

What is Anesthesia awareness ?

Estimates vary, but about 1 or 2 people in every 10,000 may be partially awake during general anesthesia and experience what is called unintended intraoperative awareness. It is even rarer to experience pain, but this can occur as well.

Because of the muscle relaxants given before surgery, people are unable to move or speak to let doctors know that they are awake or experiencing pain. For some patients, this may cause long-term psychological problems, similar to post-traumatic stress disorder.

This phenomenon is so rare that it’s difficult to make clear connections. Some factors that may be involved include:

  • Emergency surgery
  • Cesarean delivery
  • Depression
  • Use of certain medications
  • Heart or lung problems
  • Daily alcohol use
  • Lower anesthesia doses than are necessary used during procedure
  • Errors by the anesthesiologist, such as not monitoring the patient or not measuring the amount of anesthesia in the patient’s system throughout the procedure.
References
  1. Anesthesia. https://www.nigms.nih.gov/Education/pages/factsheet_Anesthesia.aspx
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Local anesthesia

local anesthesia

What is local anesthesia

Local anesthesia is used when pain control (pain relief) is required in small areas (e.g., for repair of minor lacerations, skin biopsies). An anesthetic drug (which can be given as a shot, spray, or ointment) numbs only a small, specific area of the body (for example, a foot, a single tooth, a hand, a toe or a patch of skin). With local anesthesia, a person is awake and comfortable or sedated, depending on what is needed. Local anesthesia lasts for a short period of time and is often used for minor outpatient procedures (when patients come in for surgery and can go home that same day). For someone having outpatient surgery in a clinic or doctor’s office (such as the dentist or dermatologist), this is probably the type of anesthetic used. The medicine used can numb the area during the procedure and for a short time afterwards to help control post-surgery discomfort.

Local anesthesia are often used in dentistry, for eye surgeries such as cataract removal, and to remove small skin growths including warts and moles.

Local cutaneous infiltration is the most commonly used anesthetic technique and involves direct injection into the area requiring anesthesia. The anesthetic solution is infiltrated to the deep dermis, where the sensory plexus supplying the skin begins to branch. The amount of solution used depends on the area that needs to be infiltrated.

Sometimes the local anesthetic agents are applied topically to relieve pain and itching caused by conditions such as sunburn or other minor burns, insect bites or stings, poison ivy, poison oak, poison sumac, and minor cuts and scratches.

Local and topical anesthetics deaden the nerve endings in the skin. They do not cause unconsciousness as do general anesthetics used for surgery.

Furthermore, most topical anesthetics are available without a prescription; however, your doctor may have special instructions on the proper use and dose for your medical problem.

Topical anesthetic product is available in the following dosage forms:

  • Spray
  • Solution
  • Gel/Jelly
  • Cream
  • Soap
  • Pad
  • Ointment
  • Lotion
  • Liquid
  • Patch, Extended Release
  • Film
  • Swab
  • Kit
  • Dressing
  • Patch, Device Assisted
  • Foam
  • Lozenges

How does local anesthesia work

There are two classes of infiltrative anesthetics, amides and esters, which create a reversible blockade of sodium channels within the nerve fibers by inhibiting sodium influx through sodium-specific ion channels in the neuronal cell membrane, in particular the so-called voltage-gated sodium channels 1. When the influx of sodium is interrupted, an action potential cannot arise and signal conduction is inhibited. The receptor site is thought to be located at the cytoplasmic (inner) portion of the sodium channel. Local anesthetic drugs bind more readily to sodium channels in an activated state, thus onset of neuronal blockade is faster in rapidly firing neurons. This is referred to as state-dependent blockade.

Local anesthetics can block almost every nerve between the peripheral nerve endings and the central nervous system. The most peripheral technique is topical anesthesia to the skin or other body surface. Small and large peripheral nerves can be anesthetized individually (peripheral nerve block) or in anatomic nerve bundles (plexus anesthesia). Spinal anesthesia and epidural anesthesia merge into the central nervous system.

When choosing an anesthetic agent, it is important to consider the type of procedure, the length of time required for anesthesia, and the pharmacodynamics of each medication. Table 1 is an overview of commonly used infiltrative anesthetic agents 2. True allergies to local anesthetics are rare, especially with amide preparations 3. However, evidence suggests there is cross reactivity between agents within the same class 4. In patients with a possible allergy, skin testing should be considered when immunoglobulin E–mediated reactions cannot be ruled out using the history 5.

Local anesthesia drugs

Lidocaine (Xylocaine), an amide, is the most commonly used infiltrative anesthetic and is available in several concentrations 3. For most procedures, a 0.5% or 1% solution is appropriate. Higher concentrations of lidocaine do not improve onset or duration of action and may increase the risk of toxicity 6. Adding epinephrine (concentration of 1:100,000 or 1:200,000) prolongs the duration of anesthesia, increases the maximum dose, and may aid hemostasis 7. Contrary to longstanding belief, the use of lidocaine with epinephrine on the nose, ears, digits, and penis appears to be safe 8, 9. However, many physicians still choose to avoid epinephrine use in these areas. Epinephrine should not be used in patients with peripheral artery disease.

Bupivacaine (Marcaine) is a widely used amide. It has a prolonged duration of action, but this also increases the risk of toxicity (4:1 risk of toxicity compared with lidocaine) and can cause a dose-dependent widening of the QRS interval, leading to ventricular fibrillation 10. Bupivacaine is contraindicated in pregnant women because of the increased bio-availability from decreased venous return 11.

Procaine (Novocain) and tetracaine (Pontocaine) are most often used for dental, topical, spinal, and epidural anesthesia.

Table 1. Commonly Used Infiltrative Anesthetic Agents

AgentConcentrationOnset*Duration*Maximum dose
mg per kgmL

Amides

Lidocaine (Xylocaine)

0.5%, 1%, or 2%†

Rapid: < 2 minutes

30 to 60 minutes

4 (up to 300 mg per dose)

0.5%: 60 1%: 30 2%: 15

Lidocaine with epinephrine‡

1% or 2%

Rapid: < 2 minutes§

1 to 4 hours

7 (up to 500 mg per dose)

1%: 50 2%: 25

Bupivacaine (Marcaine)

0.25% or 0.5%

Slow: 5 minutes

2 to 4 hours

2 (up to 175 mg per dose)

0.25%: 70 0.5%: 35

Esters

Procaine (Novocain)

1% or 2%

Moderate: 2 to 5 minutes

15 to 60 minutes

7 (up to 600 mg per dose)

1%: 60 2%: 30

Tetracaine (Pontocaine)

0.5%

Slow: 5 to 10 minutes

2 to 3 hours

1.4 (up to 120 mg per dose)

24


*—Similar for all concentrations of each agent.

†—Higher concentrations provide no additional anesthetic effects.

‡—Epinephrine concentration may be 1:100,000 or 1:200,000.

§—May take up to 5 minutes for epinephrine to be effective.

[Source 12]

Uses of Local anesthetics

Local anesthetics uses include:

  • Surface anesthesia is the application of an local anesthetic spray, solution, or cream to the skin or a mucous membrane; the effect is short lasting and is limited to the area of contact.
  • Infiltration anesthesia is infiltration of local anesthetic into the tissue to be anesthetized; surface and infiltration anesthesia are collectively topical anesthesia
  • Field block is subcutaneous injection of an local anesthetic in an area bordering on the field to be anesthetized.
  • Peripheral nerve block is injection of local anesthetic in the vicinity of a peripheral nerve to anesthetize that nerve’s area of innervation.
  • Plexus anesthesia is injection of local anesthetic in the vicinity of a nerve plexus, often inside a tissue compartment that limits the diffusion of the drug away from the intended site of action. The anesthetic effect extends to the innervation areas of several or all nerves stemming from the plexus.
  • Epidural anesthesia is an local anesthetic injected into the epidural space, where it acts primarily on the spinal nerve roots; depending on the site of injection and the volume injected, the anesthetized area varies from limited areas of the abdomen or chest to large regions of the body.
  • Spinal anesthesia is an local anesthetic injected into the cerebrospinal fluid, usually at the lumbar spine (in the lower back), where it acts on spinal nerve roots and part of the spinal cord; the resulting anesthesia usually extends from the legs to the abdomen or chest.
  • Intravenous regional anesthesia (Bier’s block) is when blood circulation of a limb is interrupted using a tourniquet (a device similar to a blood-pressure cuff), then a large volume of local anesthetic is injected into a peripheral vein. The drug fills the limb’s venous system and diffuses into tissues, where peripheral nerves and nerve endings are anesthetized. The anesthetic effect is limited to the area that is excluded from blood circulation and resolves quickly once circulation is restored.
  • Local anesthesia of body cavities includes intrapleural anesthesia and intra-articular anesthesia.
  • Transincision (or transwound) catheter anesthesia uses a multilumen catheter inserted through an insicion or wound and aligned across it on the inside as the incision or wound is closed, providing continuous administration of local anesthetic along the incision or wound.

How local anaesthetics are used

  • Treating pain

Slightly painful conditions such as mouth ulcers and sore throats can sometimes be treated with over-the-counter gels and sprays that contain a local anaesthetic.

Injections of a local anaesthetic and steroid medication may be used to treat more severe conditions, such as long-term joint pain.

  • Preventing pain during and after surgery

A local anaesthetic may be used along with a sedative medication to keep you relaxed while an operation or procedure is carried out.

Local anaesthetics are mainly used for relatively minor procedures, such as:

  • a filling or wisdom tooth removal
  • a minor skin operation, such as the removal of moles, warts and verrucas
  • some types of eye surgery, such as cataract removal
  • a biopsy – where a sample of tissue is removed for closer examination under a microscope

A local anaesthetic may occasionally be used for more major surgery when it’s important for you to be awake, such as during certain types of brain surgery, or to prevent pain after a major operation carried out under a general anaesthetic (see below).

  • Epidural and spinal anaesthetics

An epidural anaesthetic, often referred to as an epidural, is where a local anaesthetic is continually injected through a tube into an area of the lower back called the epidural space.

A spinal anaesthetic is a single injection into a similar space in the back.

Both types of anaesthetic can be used to numb large areas of the body by stopping pain signals travelling along the nerves in the spine.

They’re often used during childbirth to ease the pain of labour, or if a caesarean section is needed.

They can also be used to reduce the amount of general anaesthesia needed during some operations and can provide pain relief afterwards. In some types of surgery, such as knee and hip replacements, they can be used in place of a general anaesthetic.

  • Peripheral nerve blocks

A nerve block is an injection of a local anaesthetic to numb the nerves supplying a particular part of the body, such as the hand, arm or leg.

It may be used so that an operation can be carried out without needing a general anaesthetic, or to prevent pain afterwards.

An ultrasound scan is often used to pinpoint the correct nerve. The injection shouldn’t be painful and usually takes about 30 minutes to become fully effective.

When peripheral nerve blocks and epidural or spinal anaesthetics are used in place of general anaesthetics, they are often combined with sedation to make you feel drowsy and more relaxed.

Local anaesthesia risks and side effects

Local anaesthetics are generally very safe and serious problems are rare.

You may have some discomfort when the injection is given, a tingling sensation as the medication wears off, and possibly some minor bruising, bleeding or soreness where the injection was given, but you shouldn’t experience any significant side effects.

You should move carefully until the anaesthetic has worn off, as you may not notice if you injured yourself.

Some people experience temporary side effects from a local anaesthetic, such as:

  • dizziness
  • headaches
  • blurred vision
  • twitching muscles
  • continuing numbness, weakness or pins and needles

These problems will usually pass, but you should tell the healthcare professional in charge of your care if you experience any.

In very rare cases, you could have an allergic reaction to the local anaesthetic or develop serious problems such as seizures (fits) or a cardiac arrest (when the heart stops pumping blood around the body).

Local anesthesia in dentistry

A nerve block is achieved by targeting a specific nerve that supplies sensation to the desired location.

The inferior alveolar nerve, a branch of the mandibular nerve, supplies all of the teeth in one half of the mandible; it is often anesthetized in dental procedures. The same procedure will anesthetize the lower lip because the mental nerve is a branch of the inferior alveolar nerve. Because the lingual nerve runs very close to the inferior alveolar nerve near the mental foramen, it too is often anesthetized at the same time. For anesthesia to the upper teeth, the superior alveolar nerve endings, which are branches of the maxillary nerve, are blocked by inserting the needle beneath the mucous membrane. The anesthetic solution is then infiltrated slowly throughout the area of the roots of the teeth to be treated.

Figure 1. Mandibular nerve (branch of Trigeminal nerve or cranial nerve #5)

trigeminal nerve

Figure 2. Inferior alveolar nerve block

mandibular nerve block

Figure 3. Superior alveolar nerve block

superior alveolar nerve block

References
  1. Becker DE, Reed KL. Essentials of local anesthetic pharmacology. Anesth Prog. 2006;53(3):98–108.
  2. Salam GA. Regional anesthesia for office procedures: part I. Head and neck surgeries. Am Fam Physician. 2004;69(3):585–590.
  3. Liu W, Yang X, Li C, Mo A. Adverse drug reactions to local anesthetics: a systematic review. Oral Surg Oral Med Oral Pathol Oral Radiol. 2013;115(3):319–327.
  4. Berkun Y, Ben-Zvi A, Levy Y, Galili D, Shalit M. Evaluation of adverse reactions to local anesthetics: experience with 236 patients. Ann Allergy Asthma Immunol. 2003;91(4):342–345.
  5. González-Delgado P, Antón R, Soriano V, Zapater P, Niveiro E. Cross-reactivity among amide-type local anesthetics in a case of allergy to mepivacaine. J Investig Allergol Clin Immunol. 2006;16(5):311–313.
  6. Roberts JR, Hedges JR, eds. Clinical Procedures in Emergency Medicine. 5th ed. Philadelphia, Pa.: Saunders/ Elsevier; 2010:490–493.
  7. Sinnott CJ, Cogswell LP III, Johnson A, Strichartz GR. On the mechanism by which epinephrine potentiates lidocaine’s peripheral nerve block. Anesthesiology. 2003;98(1):181–188.
  8. Lalonde DH, Lalonde JF. Discussion. Do not use epinephrine in digital blocks: myth or truth? Part II. A retrospective review of 1111 cases. Plast Reconstr Surg. 2010;126(6):2035–2036.
  9. Muck AE, Bebarta VS, Borys DJ, Morgan DL. Six years of epinephrine digital injections: absence of significant local or systemic effects. Ann Emerg Med. 2010;56(3):270–274.
  10. Nath S, Häggmark S, Johansson G, Reiz S. Differential depressant and electrophysiologic cardiotoxicity of local anesthetics: an experimental study with special reference to lidocaine and bupivacaine. Anesth Analg. 1986;65(12):1263–1270.
  11. Santos AC, Pedersen H, Harmon TW, et al. Does pregnancy alter the systemic toxicity of local anesthetics? Anesthesiology. 1989;70(6):991–995.
  12. Infiltrative Anesthesia in Office Practice. Am Fam Physician. 2014 Jun 15;89(12):956-962. http://www.aafp.org/afp/2014/0615/p956.html
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Anesthesia

anesthesia

What is anesthesia

If you are having surgery, your doctor will give you medicine called an anesthetic. Anesthesia or anaesthesia is a state of temporary induced loss of sensation or awareness. The word anaesthesia is coined from two Greek words: “an” meaning “without” and “aesthesis” meaning “sensation”. Anesthesia may include analgesia (relief from or prevention of pain), paralysis (muscle relaxation), amnesia (loss of memory), or unconsciousness. A patient under the effects of anesthetic drugs is referred to as being anesthetized.

The purpose of anesthesia can be distilled down to three basic goals or end points:

  1. Hypnosis (a temporary loss of consciousness and with it a loss of memory). In a pharmacological context, the word hypnosis usually has this technical meaning, in contrast to its more familiar lay or psychological meaning of an altered state of consciousness not necessarily caused by drugs.
  2. Analgesia (block pain sensation which also blunts autonomic reflexes)
  3. Muscle relaxation

The ideal general anesthetic drug would provide hypnosis, amnesia, analgesia, and muscle relaxation without undesirable changes in blood pressure, pulse or breathing.

Anesthesia enables the painless performance of medical procedures that would cause severe or intolerable pain to an unanesthetized patient.

There are three main types anesthesia, all of which affect the nervous system in some way and can be administered using various methods and different medications 1:

  1. Local anesthesia – numbs one small area of the body. You stay awake and alert.
  2. Regional anesthesia – blocks pain in an area of the body, such an arm or leg. A common type is epidural anesthesia, which is often used during childbirth.
  3. General anesthesia – makes you unconscious. You do not feel any pain, and you do not remember the procedure afterwards.

All three involve the administration of drugs to produce a change in sensation and they are frequently used in combination. Confusion sometimes arises, because the term “ local anaesthesia” is used to refer to what is properly called “ regional anaesthesia”, so that an operation “under local” may in fact be an operation using regional anaesthesia.

You may also get a mild sedative to relax you. You stay awake but may not remember the procedure afterwards. Sedation can be used with or without anesthesia.

The type of anesthesia or sedation you get depends on many factors. They include the procedure you are having and your current health.

Factors that influence the choice of anaesthetic include:

  • The procedure to be performed. Some procedures can only be performed under general anaesthesia. For example, a patient undergoing removal of the gallbladder, whether by means of a laparoscopic or key-hole technique or through a standard incision, needs a general anaesthetic. For other procedures it is reasonable to consider whether or not the operation should be carried out under local, regional or general anaesthesia, or if a combination of techniques should be used, such as combined regional and general anaesthesia. For example, a patient undergoing an examination of the knee using a special instrument called an arthroscope could be offered a choice of local, regional, or general anaesthesia. A patient undergoing an open-heart operation might be offered a combination of general anaesthesia and regional anaesthesia.
  • The experience, expertise and preference of the anaesthetist can vary with different techniques.
  • Your own preference – whether or not you would prefer to be unconscious or wish to remain as conscious and in control as possible. Most patients prefer to be unconscious for major surgical procedures. For some procedures it is increasingly common for patients not to have a general anaesthetic—for example, caesarean section.
  • Age – It is common for children to have a general anaesthetic for procedures that might be done without any form of anaesthetic in an adult, for example, MRI (magnetic resonance imaging) scanning. This is because children may not understand the explanations or be able to lie still.

Do you have a choice?

No matter what operation, examination or other treatment you are to undergo, you may ask your anaesthetist if there is any choice in the anaesthetic method. You should also understand that some surgeons are more comfortable operating on patients who have received one form of anaesthetic rather than another. This most often means that the patient has a general anaesthetic.

The surgeon does not choose the type of anaesthetic you will receive, unless there is no anaesthetist involved in your care. However, the surgeon may discuss the choice with you and with your anaesthetist. In the same way, your anaesthetist does not choose what operation you will have or how it will be carried out. Again, your anaesthetist may discuss your operation with you and your surgeon, particularly if you have special anaesthetic problems.

Meeting your anaesthetist

You may meet your anaesthetist in a preoperative Assessment Clinic. Otherwise, you will meet shortly before you enter the Operating Room. This meeting may take place on a ward, in an admissions unit, or in a holding area outside the Operating Room.

Your anaesthetist will review information contained in your hospital record or chart, such as the results of any tests you have undergone. He or she will ask you some additional questions, such as your, or your relatives’, experience with anaesthetics. Your anaesthetist will talk to you about possible choices of anaesthetic, such as between general and regional or local anaesthesia, and about any specific problems or concerns you have. In addition, your anaesthetist will discuss with you the different choices for postoperative pain management.

After this, your anaesthetist will examine you, by looking at your mouth, your teeth, and the veins of your hands, arms, and neck, and may listen to your chest. If you are to have a regional or local anaesthetic, your anaesthetist may also look at the area of your body where the anaesthetic is to be injected, such as the small of your back.

As the last part of pre-anaesthetic assessment, the anaesthetist makes an overall evaluation of you and assigns a numerical classification. This is known as the ASA Class, where ASA stands for American Society of Anesthesiologists. Although it was developed in the United States, the ASA Class is now used worldwide as a way of classifying patients according to how well or ill they are. This classification refers only to your physical condition at the time of assessment. The higher the score, the less well you are. An ‘E’ after the appropriate classification designates that you are to undergo an emergency operation.

  • ASA Class I: A normal healthy patient
  • ASA Class II: A patient with mild systemic disease
  • ASA Class III: A patient with severe systemic disease limiting activity but not incapacitating
  • ASA Class IV: A patient with incapacitating systemic disease that is a constant threat to life
  • ASA Class V: An extremely ill patient who is not expected to live 24 hours with or without an operation.

The ASA classification is not a score of how risky the anaesthetic might be for you. However, the ASA Class has been shown to correlate with the risk of complications occurring after the operation, particularly the risk of dying. This risk is related to the operation performed and how well or ill a patient was before the procedure (or a patient’s preoperative physical condition). In general, there is very little contribution from the anaesthetic to the chance of a patient dying after a procedure.

Medications

There are types of medications which you might be asked NOT to take before your anaesthetic – some antidepressants, anticoagulants including aspirin, and diabetic drugs.

Antidepressants – monoamine oxidase inhibitors or MAOIs

There is a specific class of drugs used to treat depression, known as monoamine oxidase inhibitors or MAOIs. There is a probability of a serious drug interaction between the MAOI drug and adrenaline (epinephrine) or pethidine ( meperidine), producing an over-excitation of the brain and a potentially fatal rise in blood pressure. (The same reaction can occur if you are taking an MAOI drug and eat mouldy cheese or drink red wine.) If you are taking this type of drug and you need to have an anaesthetic, then you and your doctor or psychiatrist should arrange for the drug to be stopped before your anaesthetic. However, if you need to have an emergency operation or have not stopped taking the drug, tell your anaesthetist so he or she can avoid giving you any of the drugs which may interact.

Anticoagulants and aspirin

These drugs are used to thin the blood and reduce clotting. If you are taking warfarin or coumadin, then you must check with both your anaesthetist and surgeon for specific instructions on when and how to taper the dose of these drugs. If you have had a stroke or been threatened with one, you may be taking a type of drug known as an anti-platelet agent, or one of the non-steroidal anti-inflammatory drugs such as aspirin. You may also be taking aspirin because of heart problems or arthritis. Again, you should check with your anaesthetist and surgeon. These drugs have an effect on how certain cells in the blood stream (platelets) stick to each other when blood clots. Because the cells are no longer so sticky, there can be more bleeding during and after operations. The effects of these drugs on blood clotting may last for as long as 14 days. Some patients can stop taking these drugs without any problems before anaesthesia and surgery. However, other patients should not stop them, including those with very bad heart disease or a past stroke. Also, patients who rely on these drugs for relief of pain and other symptoms from their arthritis may find that their joints are much more painful if they stop the tablets. Again, it is vital that you ask the doctor who normally looks after you, as well as your anaesthetist and surgeon.

Diabetic drugs and insulin

If you normally take tablets for the control of blood sugar for diabetes, you should not do so on the day you are to have your anaesthetic. If you do so and then go without eating (fasting), your blood sugar might drop very low while you are under the anaesthetic, when you cannot complain of the symptoms of low blood sugar or hypoglycemia. In addition, one of these drugs, metformin, has been associated with the development of a severe condition where acid builds up in the blood stream. The probability of this developing is more likely in patients who undergo certain procedures, such as heart operations where the heart-lung machine is used.

On the other hand, if you are taking insulin for control of diabetes, you will want to discuss how best to manage your insulin. Ideally, patients with diabetes should be scheduled to undergo their procedures as the first case of the day. This will allow them more time during the day to recover and perhaps be able to start back on a reasonably normal diet. Some diabetics will be asked to take less than their normal dose of insulin. A few diabetics might even omit taking any insulin until the procedure is over and they are capable of eating or drinking again. All diabetic patients should have their blood sugar tested immediately before the operation and again when they arrive in the recovery room. Some patients also have their blood sugar tested during the procedure by their anaesthetist.

Alcohol

Anaesthetists recommend that you do not have anything alcoholic to drink on the day before and the day of the operation. In general, patients who drink alcohol every day need higher doses of anaesthetic drugs than those patients who do not consume any alcohol. So it is also important to tell your anaesthetist exactly how much alcohol you drink and how often.

Herbal and OTC medications

Many patients now take herbal and other ‘over the counter’ (OTC) medications and supplements. Some of these medications may interact with anaesthetic drugs, as well as those used to relieve pain in the postoperative period. For example, St. John’s Wort is a herbal preparation commonly used by patients who are feeling ‘blue’ or a little depressed. This herb is known to affect the length of time that certain prescription drugs last, as well as some anaesthetic agents.

Other non-prescription items of importance are antacids, such as Mylanta, Maalox, or Pepto-Bismul. These antacids come either as a thick creamy liquid or as tablets. You should not take any of these after the midnight before your operation. If inhaled into your lungs, these antacids can cause damage from the tiny particles from which they are made.

You should therefore give your anaesthetist a complete list of every herbal, vitamin, and supplement you are taking, in addition to your prescription medications. Some anaesthetists actually prefer that you bring to the hospital or clinic all of the medications, herbals, supplements and vitamins that you actually take, even if it means bringing them in a ‘shopping bag’. That way, your anaesthetist can read the labels of each of the containers. This is particularly important if you are taking unusual supplements or those that contain more than one ingredient.

Smoking

Ideally, you should stop smoking six months before the operation. If you do quit, you may notice that you have a cough and are bringing up some phlegm. This is usually a sign that your lungs are starting to recover from the effects of the nicotine and the smoke. However, you may not have that much time to quit before the operation, or you may be unable to quit entirely. In either case, decreasing the number of cigarettes and the amount smoked of each cigarette will help. Using nicotine gum or a nicotine patch may make it easier, although neither should be used on the day you have your anaesthetic.

Street drugs

It is vital for your anaesthetist to know what drugs you have used in the past and when. Street or ‘recreational’ drugs, such as heroin, LSD and cocaine, can strongly influence the anaesthetic. Cocaine and ecstasy are two drugs that excite the nervous system. They may excite your heart, producing dangerous swings in blood pressure and heart rate, both during and after the operation. Drugs such as LSD can produce hallucinations, which may cause flashbacks in the postoperative period. As a general rule, it is safer not to use any of these drugs for at least one week before your anaesthetic and operation.

Premedications

Many people think of the ‘premed’ as being a tablet or injection given to produce a state of calmness. In fact, the term premedication refers to the prescribing of all drugs before anaesthesia and surgery.

These drugs may be prescribed to make you less anxious, to relieve pain, to lessen the possibility of your inhaling stomach acid into your lungs, and to lessen the possibility of your having any postoperative nausea and vomiting. In addition, you may also be given antibiotics to reduce the potential for infection. In the past, many of these drugs were given by injection. However, anaesthetic practice has changed and now almost all of these drugs can be given in tablet or liquid form.

Sedatives

If you are extremely anxious, ask your anaesthetist or your surgeon for something to calm you. In the past, many different drugs were used to help patients feel less anxious before anaesthesia. These drugs included barbiturates and antihistamines. Currently, you might receive one of a class of drugs known as benzodiazepines, such as midazolam, temazepam or diazepam. You may be given a single tablet or a prescription for something to take at home the night before the operation. Or you may be given a tablet, or less often, an injection, once you arrive at the hospital. However, many patients are not admitted to hospital until shortly before the operation. Because of this, you might not receive any form of sedative premed.

You may prefer not to receive any form of sedation, as this will enable you to remain in control for as long as possible before your anaesthetic and operation. Another reason is that studies have shown that patients who do not receive any sedation recover from the effects of the anaesthetic more quickly than those who were sedated beforehand. Older patients tend to remain sleepy for longer and may also have some problems with memory when sedated to reduce preoperative anxiety.

Painkillers

In the past, patients were often given an injection of a painkiller, such as pethidine. This injection was designed to help reduce anxiety and also to supplement the drugs given at the time of the anaesthetic. Some patients, such as those undergoing open-heart surgery, may be given an injection of a sedative and a painkiller. This helps to ensure that they are calm before the operation and that the heart is not stressed. Many anaesthetists no longer give pain-relieving drugs until the patient is actually in the Operating Room, unless the patient is already in pain.

If you are taking painkillers, such as narcotics, it is important to continue taking them so that your pain does not get out of control. But your anaesthetist needs to know about them in order to plan which drugs to give you both during and after the operation. (See also ‘Postoperative pain relief’.)

Antacids

Another group of drugs that you might be given are those that lessen any chance that you might inhale some of the acid contents of your stomach into your lungs, either during or after anaesthesia. If you are so unfortunate as to suffer this complication, there is an immediate possibility of suffocation by any large pieces of partially digested food that are present in your stomach. There is also a later risk of severe pneumonia from the acid contacting delicate lung tissue. This complication is known as pulmonary aspiration of gastric acid and is potentially lethal.

Three types of drugs can be used to lessen the chances of this occurring in patients who are considered at risk.

  1. A drug that will decreases the production of acid, such as cimetidine or ranitidine, which are know as histamine2 (H-2) receptor-blocking agents.
  2. A drug to help neutralize acid in your stomach, such as the antacid sodium citrate. Taken by mouth, sodium citrate makes your stomach contents less acid (by increasing the pH). Unlike other antacids, sodium citrate is a clear liquid and does not contain any small particles that could damage your lungs if you inhale any stomach contents.
  3. A drug to increase the rate at which your stomach empties into the small intestine, thus decreasing the volume of fluid in your stomach. One drug used for this purpose is metoclopramide.

There are no set rules or strict guidelines for the use of any of these drugs. If you were to undergo a caesarean section, you might be given some sodium citrate. Some anaesthetists use H-2 receptor blockers in patients who have a hiatus hernia or heartburn. If you are extremely obese (fat), then you might be given all three types of drugs. (People who are very fat tend to have large volumes of very acid fluid in the stomach.

Antiemetics

Antiemetics are now commonly administered routinely, especially if you have suffered from nausea and vomiting after a previous procedure. There are a variety of antiemetics, which may be given by various routes, however, they are usually administered intravenously after the start of the anaesthetic. Some, like ondansetron, may be taken orally.

Antibiotics

In addition, your surgeon may ask that you be given a dose of antibiotics before the procedure, because the prophylactic use of antibiotics has been shown to reduce the possibility of infection. You are most likely to be given ‘prophylactic’ antibiotics if you are to undergo almost any type of major operation, such as a hip replacement, and even some more minor ones, such as a simple hernia repair. Your surgeon may also order antibiotics if you are having a device, such as a pacemaker, implanted. Generally, your anaesthetist is not responsible for ordering antibiotics for this purpose, although he or she might order ‘prophylactic’ antibiotics if you have problems with your heart valves. (Another doctor, such as a heart specialist or surgeon, may also take responsibility for ordering them.)

Sometimes these antibiotics are given in the hour before the operation. In other cases your anaesthetist administers them, usually at the start of the anaesthetic. This ensures that the amount of antibiotic in your blood is as high as possible at the time of the operation.

How does anesthesia work

Depending on the type of pain relief needed, the anesthesiologist (a medical doctor trained in anesthesia and perioperative medicine) delivers anesthetics by injection, inhalation, topical lotion, spray, eye drops, or skin patch. Anesthesiologists are also experts in pain management, they often advise patients and their doctors on how to manage pain.

In preparing for a medical procedure, the anesthesiologist giving anesthesia will choose and determine the doses of one or more drugs to achieve the types and degree of anesthesia characteristics appropriate for the type of procedure and the particular patient. The types of drugs used include general anesthetics, hypnotics, sedatives, neuromuscular-blocking drugs, narcotic, and analgesics.

For many years, doctors called general anesthetics a “modern mystery.” Even though they safely administered anesthetics to millions of Americans, they didn’t know exactly how the drugs produced the different states of general anesthesia. These states include unconsciousness, immobility, analgesia (lack of pain) and amnesia (lack of memory). Understanding anesthetics has been challenging for a number of reasons. Unlike many drugs that act on a limited number of proteins in the body, anesthetics interact with seemingly countless proteins and other molecules. Additionally, some anesthesiologists believe that anesthetics may work through a number of different molecular pathways. This means no single molecular target may be required for an anesthetic to work, or no single molecular target can do the job without the help of others. Most researchers agree that the anesthetic drugs target proteins in the membranes around nerve cells. Because inhaled anesthetics have different effects than intravenous ones, scientists suspect that the two different types of drugs target different sets of proteins.

The anesthesiologist will be there before, during, and after the operation to monitor the anesthetic and ensure you constantly receive the right dose.

The anesthesiologist uses highly advanced electronic devices that constantly display patients’ blood pressure, blood oxygen levels, heart function, and breathing patterns. These devices have dramatically improved the safety of general anesthesia. They also make it possible to operate on many patients who used to be considered too sick to have surgery.

In addition to giving anesthesia medicine to prepare you for the surgery, the anesthesiologist will:

  • monitor your major bodily functions (such as breathing, heart rate and rhythm, body temperature, blood pressure, and blood oxygen levels) during surgery
  • address any problems that might arise during surgery
  • manage any pain you may have after surgery
  • keep you as comfortable as possible before, during, and after surgery.

With general anesthesia, the anesthesiologist uses a combination of various medications to do things like:

  • relieve anxiety
  • keep you asleep
  • minimize pain during surgery and relieve pain afterward (using drugs called analgesics)
  • relax the muscles, which helps to keep you still
  • block out the memory of the surgery.

To better understand how the different types of anesthesia work, it may help to learn a little about the nervous system. If you think of the brain as a central computer that controls all the functions of your body, then the nervous system is like a network that relays messages back and forth from it to different parts of the body. It does this via the spinal cord, which runs from the brain down through the backbone and contains threadlike nerves that branch out to every organ and body part.

Often, anesthesiologists may give a person a sedative to help them feel sleepy or relaxed before a procedure. Then, people who are getting general anesthesia may get medication through a breathing mask first and then be given an IV after they’re asleep. Why? Many people are afraid of needles and may have a hard time staying still and calm, so doctors may need to help them relax first with this medicine.

During your anaesthetic

There are three phases to any anaesthetic.

  • Start or induction phase: In the case of a general anaesthetic the anaesthetist gives you the drugs that make you lose consciousness, or he or she performs the nerve block that makes part of you numb (as in a spinal or an epidural).

In some hospitals, you are taken directly into the Operating Room and then given your anaesthetic. In other hospitals, you are taken into a smaller room adjacent to the Operating Room. This smaller room is known as the Anaesthetic Induction Room, as it is where the anaesthetic is ‘induced’ or started.

In either case, you will have ‘routine monitors’ attached, which are used for virtually every patient. These include an ECG ( electrocardiograph), a pulse oximeter probe, and a blood pressure cuff. In addition, in most cases an intravenous line is started, usually in a vein in the back of one of your hands or in a vein in your forearm.

  • Middle or maintenance phase: The anaesthetist ensures that you remain anaesthetised until the surgical, diagnostic or other treatment procedure is completed.
  • End or emergence phase: The anaesthetist stops giving you the anaesthetic drugs, allows them to wear off, and/or gives you other drugs to reverse their effects, so that you regain consciousness or sensation.

Types of anesthesia

Local anesthesia

An anesthetic drug (which can be given as a shot, spray, or ointment) numbs only a small, specific area of the body (for example, a foot, a single tooth, a hand, a toe or a patch of skin). With local anesthesia, a person is awake and comfortable or sedated, depending on what is needed. Local anesthesia lasts for a short period of time and is often used for minor outpatient procedures (when patients come in for surgery and can go home that same day). For someone having outpatient surgery in a clinic or doctor’s office (such as the dentist or dermatologist), this is probably the type of anesthetic used. The medicine used can numb the area during the procedure and for a short time afterwards to help control post-surgery discomfort.

Local anesthesia are often used in dentistry, for eye surgeries such as cataract removal, and to remove small skin growths including warts and moles.

Regional anesthesia

Regional anesthetics affect larger areas, such as an arm, a leg or everything below the waist. An anesthetic drug is injected near a cluster of nerves, which block transmission of nerve impulses between a targeted part of the body and the central nervous system, causing loss of sensation in the targeted body part – numbing a larger area of the body e.g. epidural anesthesia (such as below the waist, like epidurals given to women in labor) and spinal anesthesia. This type of anesthesia is used for hand and joint surgeries, to ease the pain of childbirth, or during a C-section delivery. A patient under regional or local anesthesia remains conscious, unless general anesthesia or sedation is administered at the same time. Regional anesthesia is generally used to make a person more comfortable during and after the surgical procedure. Regional and general anesthesia are often combined.

Local anaesthetic nerve blocks

The term ‘regional’ refers to the fact that only part of the body is anaesthetised. In some parts of the world, ‘ regional anaesthesia’ may be known as ‘ local anaesthesia’. The term ‘ nerve block’ means that the transmission of impulses in the nerve or nerves from the area of the operation is blocked by the injection of local anaesthetic drugs around the nerve(s). You will feel numb or ‘frozen’ in the area of the block. Local anaesthetics can be administered around the nerves in the spinal cord, either as a spinal or as an epidural anaesthetic. Local anaesthetics can also be injected close to other nerves, such as those in the arms or legs. Because these nerves tend to be in the body’s extremities, these nerve blocks may be called peripheral nerve blocks.

Local anaesthetics may also be used to numb certain internal membranes such as the lining of the mouth or throat, or the urethra for examination of the bladder.

The choice of which particular block to use is based in part on the anaesthetist’s experience and the potential for the block to cause side-effects. The major problems that occur with nerve blocks are related to the needle and to the agent injected. The needle can cause damage to nerves and to other neighbouring structures. For example, a block of the major group of nerves to the arm, when performed at a site just above the collarbone (‘supraclavicular approach to the brachial plexus’) is associated with a 1 or 2 per cent risk of damage to the lung (pneumothorax). This is because of the nerves are close to the outer lining of the lung.

Injection of local anaesthetic agents can cause side-effects because of allergic reactions, or because of misplacement of the needle. Because an artery and vein surround each nerve, it is possible to inject local anaesthetic into either of these blood vessels. This results in a sudden increase in the concentration of local anaesthetic in the bloodstream, which can cause convulsions and cardiac arrest. To reduce the chances of these complications, nerve blocks should be performed in the Operating Room or in a specially equipped room, where monitors and resuscitation equipment are available. This equipment includes oxygen, a means of delivering the oxygen to the lungs, suction apparatus (in case of vomiting), and items for tracheal intubation. It is vital to have properly trained assistance available.

There are different types of local anaesthetics that act for different lengths of time. By choosing various drugs, your anaesthetist can tailor the length of your anaesthetic to match the length of the operation. Sometimes the anaesthetist inserts a fine plastic tube through the nerve block needle. This allows your anaesthetist to give you one or more injections of local anaesthetic, without having to re-insert the needle. This is known as giving a ‘top-up’.

Testing the block

Your anaesthetist then checks to see how well the block has worked, by touching your skin with an ice cube or an alcohol swab. If the block has worked, you cannot feel ‘cold’ when touched. Some anaesthetists use a very fine sterile needle and ask you if the needle feels ‘sharp’ (where the area supplied by the nerve is not blocked) or ‘blunt’ (where the nerve is blocked).

What will you feel ?

The aim of any nerve block is to stop you feeling any pain. However, it is important to remember that you might feel touch, pressure, or vibration, and this is considered normal for certain blocks using certain drugs.

Most anaesthetists like to remind their patients that they may feel ‘something’ but are very unlikely to feel pain. If the block does not work, there are several options:

  • The block can be repeated.
  • If the area of sensation is small, the surgeon might be able to inject a small amount of local anaesthetic into the area where you felt the pain.
  • Your anaesthetist can give you some medication for pain, such as a low concentration of nitrous oxide or a small amount of an injected opiate or narcotic.
  • A general anaesthetic may be given instead.
  • Finally, in some patients, it is better to cancel the procedure and try again another day.

During the Procedure

After determining that your block has worked, your anaesthetist helps the nurse to set up the sterile drapes or sheets that separate you from where the surgeon is working. These drapes also prevent you from seeing what is being done. Your anaesthetist continues to monitor how you feel in general, and your vital signs (blood pressure, heart rate, and oxygen saturation). During the course of the procedure, depending on how you are feeling, your anaesthetist might choose to give you an intravenous injection of a sedative, to relax you. You will feel drowsy and might even drift off into what seems like a light sleep. At the end of the operation you will probably not remember much about the events in the Operating Room. When you are transferred to the recovery room, you feel relaxed, free of pain and quite awake.

Spinal anaesthesia

The most common types of nerve blocks are spinals and epidurals. The spinal cord is surrounded by fluid within a tough fibrous envelope called the ‘dura’. With a spinal, the drug is injected into the fluid. With an epidural, the drug is placed outside the dura, but still within the hollow spinal canal of the backbone.

Spinal anaesthetics are useful for surgical procedures involving the legs and lower abdomen. Typical surgical procedures include caesarean section, vaginal hysterectomy, operations on the prostate, repair of inguinal or groin hernias, repair of a fractured hip, and arthroscopic examination of the knee.

There are a few reasons why you might not be suitable for a spinal anaesthetic. It might be your choice not to have a spinal. The other major reasons have to do with an increased risk of complications from this technique. These include an infection at the site where the needle is inserted, increased pressure around the brain (from a tumour, a build-up of spinal fluid, or the presence of a blood clot) and problems with poor blood clotting. All of these are extremely rare.

If you have a spinal anaesthetic, your anaesthetist first attaches various monitors (ECG, blood pressure cuff, pulse oximeter), and starts an intravenous line. You are then positioned, either lying on one side or sitting up on the edge of the Operating Room table or trolley. If you are lying down, you are asked to curl up into a ball, with your knees drawn up to your chin (or as high as possible). If you are sitting up, you lean over a pillow placed on a small table. In either case, a nurse or the anaesthetist’s assistant helps you to get into position and to remain as still as possible. You have a sheet or blanket to cover your chest and the lower half of your body.

Then your anaesthetist feels the bones of your back to choose the level to insert the spinal needle. The site most often chosen is about 4 – 5 centimetres below your waist and right in the middle (‘midline’). After this, your anaesthetist scrubs up, and puts on sterile gloves and often a sterile gown as well. After washing a small area in the middle of your back, using antiseptic solution (which is usually cold), the anaesthetist covers the surrounding skin with sterile cloths.

The next step is insertion of the needle, during which it is extremely important for you to hold as still as possible. Your anaesthetist first gives you a small injection of some local anaesthetic into the area where the spinal needle will be inserted. This injection might feel like a small bee-sting. Then the specially designed spinal needle is inserted into the epidural space and through the covering over the spinal cord (dura). Sometimes there is a tiny ‘pop’ or ‘click’ when this happens. Once the spinal needle penetrates the dura, it sits in the spinal canal. This is a sack-like structure containing the cerebrospinal fluid, nerve roots, and the spinal cord. Local anaesthetics (and sometimes a painkiller) are injected into the spinal fluid through the needle, which is then removed.

After the needle is removed, it is safe for you to move a little bit. If you are sitting up, your anaesthetist has you lie down after about 30 seconds. If you were lying down, you continue to lie in that position, although you could straighten your legs and your neck. The local anaesthetic solution disperses in the spinal fluid and blocks the nerves. Over the next few minutes you develop profound numbness and weakness in the lower half of your body (or one side more than the other if the spinal was inserted when you were lying on one side).

The major immediate complications of spinal anaesthetics include nerve damage from the needle, a decrease in blood pressure and heart rate, and failure of the injection to produce an adequate level of anaesthesia. The chance of the block not working is about one per cent or less, depending on how frequently your anaesthetist performs spinal blocks.

The long-term complications of spinal anaesthesia include a 1 per cent chance of severe headache afterwards. Termed a post-dural puncture headache, this type of headache is unusual in that it comes on when a patient sits or stands up and is completely resolved by lying down. (The medical term for this phenomenon is ‘posturally dependent headache’.) Specific treatment may be needed for the headache.

One extremely rare complication of spinal anaesthesia includes compression of the spinal cord from a blood clot or abscess in the spinal canal. Another rare complication is ongoing nerve damage from chemical effects of the anaesthetic or other agents on the nerve roots.

A slightly more common complaint is irritation of a nerve root (radicular irritation syndrome). With this problem, patients report burning pain in the legs. The pain comes on a few days after having a spinal with certain local anaesthetic drugs. Fortunately, the pain goes away without any treatment.

Epidural anaesthesia

Like spinal anaesthesia, epidural anaesthesia can be used for operations on the legs and the lower part of the abdomen. Epidurals can also be inserted to help with pain management, either after an operation or during labor.

The spinal cord is surrounded by fluid within a tough fibrous envelope called the ‘dura’. With a spinal, the drug is injected into the fluid. With an epidural, the drug is placed outside the dura, but still within the hollow spinal canal of the backbone. The technique of insertion of the epidural needle is similar to that used for spinal anaesthesia. However, the needle is stopped in the epidural space and there is no attempt to penetrate the dura. Usually, epidural anaesthesia is performed using a larger needle through which a fine plastic tube (catheter) can be threaded into the epidural space. This tube is similar to fine cooked spaghetti and it is not always possible to determine where the tip of the catheter ends up. Occasionally a patient complains of a brief, shock-like sensation as the catheter is being threaded through the needle and into the back. Most anaesthetists warn their patients that this might happen and remind them not to move until the needle is withdrawn. Once the catheter is well situated, the needle is removed. The catheter is then taped up the back and secured to the hospital gown. A filter is attached to the catheter – in case the fluid to be injected contains tiny particles of glass from the drug ampoules, and to keep bacteria out.

Epidurals are often inserted to relieve the pain of labor and childbirth, as well as postoperative pain. In such cases, epidural analgesia is provided instead of epidural anaesthesia. The only difference between anaesthesia and analgesia is that analgesia uses weaker concentrations of local anaesthetic. An opiate or narcotic may also be injected into the epidural to increase pain relief. Epidurals differ from spinals in that a much larger dose of local anaesthetic is required for an epidural anaesthetic as compared to a spinal anaesthetic.

Epidurals can be inserted into the upper part of the back (the thoracic spine), and are then known as thoracic epidurals. These are particularly useful for the relief of postoperative pain after operations on the chest (thoracic surgery). In addition, the anaesthetist may use the pain relief from the epidural to reduce the amount of general anaesthetic needed during the operation.

The immediate risks from epidural anaesthesia include a decrease in blood pressure, and seizures from the accidental intravenous injection of local anaesthetic agents. In addition, effects similar to spinal anaesthesia can be seen, but because of the larger dose of local anaesthetic used with epidurals, the patient may be anaesthetised from the neck down.

The long-term complications of epidural anaesthesia include a less than 1 per cent chance the block failing to work, and a similar chance of having a post-dural puncture headache. Also possible is damage to a nerve root from the epidural needle or catheter. In extremely rare cases, an epidural blood clot ( haematoma) or abscess may occur, resulting in weakness of the legs and in loss of bowel and bladder control.

Other nerve blocks

Other parts or regions of the body can also be anaesthetised (‘frozen’) – for example, for operations on an eye, arm, or foot. Many different techniques have been described for such operations.

Operations on the eye can be performed under retrobulbar or peribulbar block. These blocks involve injecting local anaesthetic around the eyeball, so that the eye is pain-free and unable to move. This kind of block is used for many operations on the eye, including cataract extraction with lens insertion and repair of defects on the retina (back of the eye). Some cataract operations can also be performed under local anaesthesia, after local anaesthetic drops have been applied to the surface of the eye.

For surgery on the arm it is possible to provide satisfactory anaesthesia by blocking the major group of nerves (brachial nerve plexus) that supplies the shoulder and arm. A block may be performed at one of a number of different sites, including:

  • in the neck (interscalene)
  • above the collar bone (supraclavicular)
  • below the collar bone (infraclavicular)
  • and in the armpit (axillary).

For surgery on the leg it is possible to provide satisfactory anaesthesia by blocking the major group of nerves (sciatic nerve or femoral nerve) that supplies the hip, leg and foot. A block may be performed at one of a number of sites, including:

  • in the groin (inguinal)
  • under the buttocks
  • at the back of the knee (popliteal fossa)
  • and at the ankle.

The intravenous technique, or Bier’s block, can be used for operations on the arm, such as reduction of simple fractures of the wrist, and less commonly for procedures on the leg. With this technique, a special tourniquet with two cuffs is wrapped around the arm or leg to be anaesthetised. An intravenous cannula is inserted into a vein in the hand or foot, but no intravenous line is attached. The anaesthetist then lifts up the arm or leg and wraps a tight rubber bandage around it, to drain the blood. The tourniquet cuff closer to the head is then inflated and the rubber bandage is removed. The arm or leg is lowered and local anaesthetic is injected through the intravenous cannula. After at least five minutes, the lower tourniquet cuff is inflated. Once this has been secured, the upper cuff is released. This sequence ensures that the patient does not feel any pain from the tourniquet, which must remain inflated for at least 45 minutes. If the tourniquet is released prematurely, there would be an increased chance that the local anaesthetic will rush through the patient’s blood vessels to the heart and brain. The effect on the heart would be to decrease the heart rate and blood pressure. The effect on the brain might be to cause seizures or loss of consciousness.

General anesthesia

General anesthesia suppresses central nervous system activity and results in unconsciousness, complete muscle paralysis and total lack of sensation 2. The goal is to make and keep a person completely unconscious (or “asleep”) during the operation, with no awareness or memory of the surgery. General anesthesia can be given through an IV (which requires sticking a needle into a vein, usually in the arm) or by inhaling gases or vapors by breathing into a mask or tube. General anesthesia delivered intravenously will act quickly and disappear rapidly from the body. This allows patients to go home sooner after surgery. Inhaled anesthetics may take longer to wear off.

Surgeons use general anesthesia when they operate on internal organs and for other invasive or time-consuming procedures such as back surgery. Without general anesthesia, many major, life-saving procedures would not be possible, including open-heart surgery, brain surgery and organ transplants.

General anesthetics typically are very safe. But they can pose risks for some patients, such as the elderly or people with chronic illnesses such as diabetes. Also, side effects may linger for several days in some patients, especially the elderly and children.

General anesthesia side effects

General anesthesia is overall very safe; most people, even those with significant health conditions, are able to undergo general anesthesia itself without serious problems.

General anesthetics side effects—such as dangerously low blood pressure—are much less common than they once were. Still, as with any medical procedure, some risks exist. To minimize these risks, specialized doctors called anesthesiologists carefully monitor unconscious patients and can adjust the amount of anesthetic the patients receive.

In fact, your risk of complications is more closely related to the type of procedure you’re undergoing and your general physical health, rather than to the type of anesthesia.

Older adults, or those with serious medical problems, particularly those undergoing more extensive procedures, may be at increased risk of postoperative confusion, pneumonia, or even stroke and heart attack.

Specific conditions that can increase your risk of complications during surgery include:

  • Smoking
  • Seizures
  • Obstructive sleep apnea
  • Obesity
  • High blood pressure
  • Diabetes
  • Other medical conditions involving your heart, lungs or kidneys
  • Medications, such as aspirin, that can increase bleeding
  • History of heavy alcohol use
  • Drug allergies
  • History of adverse reactions to anesthesia

These risks are generally related to the surgery itself, not the anesthesia.

What is Anesthesia awareness ?

Estimates vary, but about 1 or 2 people in every 10,000 may be partially awake during general anesthesia and experience what is called unintended intraoperative awareness. It is even rarer to experience pain, but this can occur as well.

Because of the muscle relaxants given before surgery, people are unable to move or speak to let doctors know that they are awake or experiencing pain. For some patients, this may cause long-term psychological problems, similar to post-traumatic stress disorder.

This phenomenon is so rare that it’s difficult to make clear connections. Some factors that may be involved include:

  • Emergency surgery
  • Cesarean delivery
  • Depression
  • Use of certain medications
  • Heart or lung problems
  • Daily alcohol use
  • Lower anesthesia doses than are necessary used during procedure
  • Errors by the anesthesiologist, such as not monitoring the patient or not measuring the amount of anesthesia in the patient’s system throughout the procedure.

How you prepare for a general anesthesia

General anesthesia relaxes the muscles in your digestive tract and airway that keep food and acid from passing from your stomach into your lungs. Always follow your doctor’s instructions about avoiding food and drink before surgery.

Fasting is usually necessary starting about six hours before your surgery. You may be able to drink clear fluids until a few hours prior.

Your doctor may tell you to take some of your regular medications with a small sip of water during your fasting time. Discuss your medications with your doctor.

You may need to avoid some medications, such as aspirin and some other over-the-counter blood thinners, for at least a week before your procedure. These medications may cause complications during surgery.

Some vitamins and herbal remedies, such as ginseng, garlic, Ginkgo biloba, St. John’s wort, kava and others, may cause complications during surgery. Discuss the types of dietary supplements you take with your doctor before your surgery.

If you have diabetes, talk with your doctor about any changes to your medications during the fasting period. Usually you won’t take oral diabetes medication the morning of your surgery. If you take insulin, your doctor may recommend a reduced dose.

If you have sleep apnea, discuss your condition with your doctor. The anesthesiologist or anesthetist will need to carefully monitor your breathing during and after your surgery.

What you can expect from a general anesthesia

Before the procedure

Before you undergo general anesthesia, your anesthesiologist will talk with you and may ask questions about:

  • Your health history
  • Your prescription medications, over-the-counter medications and herbal supplements
  • Allergies
  • Your past experiences with anesthesia

This will help your anesthesiologist choose the medications that will be the safest for you.

During the procedure

Your anesthesiologist usually delivers the anesthesia medications through an intravenous line in your arm. Sometimes you may be given a gas that you breathe from a mask. Children may prefer to go to sleep with a mask.

Once you’re asleep, the anesthesiologist may insert a tube into your mouth and down your windpipe. The tube ensures that you get enough oxygen and protects your lungs from blood or other fluids, such as stomach fluids. You’ll be given muscle relaxants before doctors insert the tube to relax the muscles in your windpipe.

Your doctor may use other options, such as a laryngeal airway mask, to help manage your breathing during surgery.

Someone from the anesthesia care team monitors you continuously while you sleep. He or she will adjust your medications, breathing, temperature, fluids and blood pressure as needed. Any issues that occur during the surgery are corrected with additional medications, fluids and, sometimes, blood transfusions.

Blood transfusions may sometimes be necessary, such as during complex surgeries. The anesthesia care team monitors your condition and delivers blood transfusions when needed. Blood transfusions may involve risks. These risks are greater in people who are older, have low red blood cell volume or are undergoing complex heart surgeries.

After the procedure

When the surgery is complete, the anesthesia medications are stopped, and you slowly wake either in the operating room or the recovery room. You’ll probably feel groggy and a little confused when you first wake. You may experience common side effects such as:

  • Nausea
  • Vomiting
  • Dry mouth
  • Sore throat
  • Shivering
  • Sleepiness
  • Mild hoarseness

You may also experience other side effects after you awaken from anesthesia, such as pain. Side effects depend on your individual condition and the type of surgery. Your doctor may give you medications after your procedure to reduce pain and nausea.

What Type of Anesthesia Will You Get ?

The type and amount of anesthesia given to you will be specifically tailored to your needs and will depend on various factors, including:

  • the type of surgery
  • the location of the surgery
  • how long the surgery may take
  • your current and previous medical condition
  • allergies you may have
  • previous reactions to anesthesia (in you or family members)
  • medications you are taking
  • your age, height, and weight

The anesthesiologist can discuss the options available, and he or she will make the decision based on your individual needs and best interests.

Before Surgery

Although you may be able to talk to the anesthesiologist a day or two prior to the operation, you might not meet until that day. Either way, the anesthesiologist will go over your medical history and information thoroughly, so that he or she can make the right choice regarding anesthetic medications tailored to your individual needs.

To ensure your safety during the surgery, you’ll need to answer all of the anesthesiologist’s questions as honestly and thoroughly as possible. Things that may seem harmless could interact with or affect the anesthesia and how you react to it.

The anesthesiologist might order additional tests (such as X-rays or blood or laboratory tests) to help figure out the best possible personalized anesthetic plan for you.

In addition to doing a physical examination of your airways, heart, and lungs, the anesthesiologist will also want to get your medical history, which will include asking about:

  • your current and past health
  • your family’s health
  • any medications, supplements, or herbal remedies you are taking (consider bringing a list of exactly what you take, detailing how much and how often)
  • any previous reactions you or any blood relative has had to anesthesia
  • any allergies (especially to foods, medications, or latex) you may have
  • whether you smoke, drink alcohol, or take recreational drugs.

Eating and Drinking Before Anesthesia

The anesthesiologist, surgeon, or someone on the nursing staff will give you instructions about not eating or drinking before surgery. It’s important to make sure you don’t eat anything prior to surgery (usually nothing after midnight the day before the operation). You’ll get specific instructions based on your age, medical condition, and the time of day of the procedure.

Why is fasting important ?

If you vomit when you are awake, or even when you are asleep at night (and not anaesthetised), your reflexes prevent any of that vomit being aspirated (or inhaled) into your lungs. You cough and splutter to clear the area around the back of your throat and larynx. Then you can breathe again.

When anaesthetised (or very drunk, or affected by an overdose of sedatives or certain street drugs), you may be able to vomit but some of your protective reflexes do not work. There is therefore a possibility that fluid from the stomach will regurgitate – that is, run up your oesophagus and into the back of your throat. Should this happen when your level of consciousness is decreased, then you cannot protect yourself by swallowing and coughing. The fluid may then pass into your windpipe or trachea and down into your lungs. This is known as aspiration. Should you inhale some stomach contents, then there is the risk of suffocation, particularly if undigested food is present. The acid in your lungs may also cause severe wheezing and a lack of oxygen. Later, pneumonia may develop. This pneumonia is a particularly severe form because of the effect of the acid on the delicate tissue of the lungs.

How long do patients go without food or drink ?

Until about ten years ago, it was common for patients scheduled for elective surgery to fast from midnight on the night before surgery. If the operation was scheduled in the afternoon, patients had to fast for periods of up to 16 – 18 hours. In the late 1980s, a number of scientific studies were carried out that questioned the validity of this fasting policy. In some countries, professional organisations have changed their recommendations to allow shorter hours of fasting. For example, the Canadian Anaesthetists’ Society produced a revision to the Guidelines to the Practice of Anaesthesia in 1996. These new guidelines stated that fasting policies should take into account the age of the patient, as well as any medical problems that the patient might have. The guidelines also recommended that a patient should not eat any solid foods on the day of surgery, but could drink clear fluids up to three hours before the operation. Despite increasing amounts of scientific evidence about the safety of following guidelines such as these, standard textbooks of anaesthesia still recommend that patients be ‘ NPO ’ (‘Nil per os’ or ‘nothing by mouth’) for six to eight hours before anaesthesia and surgery. It is likely that such statements will change in the future, although anaesthetists still recommend in general that patients do not eat any solid food after midnight before the scheduled operation.

Emergency surgery

If you have been in an accident, are in pain, or have been given an injection of a painkiller, the speed at which food leaves your stomach and passes downwards is slowed. This results in you having what anaesthetists term a ‘ full stomach’, which increases the possibility of stomach contents being regurgitated back up the throat. Theoretically, your operation could be delayed until your stomach had emptied, although this is not always appropriate. There are ways of minimising the possibility of regurgitation of gastric contents. Some patients may need to have a nasogastric inserted through the nose, down the oesophagus, and into the stomach. The fluid in the stomach can then be suctioned out through the tube, although removing solids is still a problem. This technique is important in patients who have an obstruction of the bowel. Unfortunately, suctioning cannot ensure that the stomach is empty, but only one that is ‘less full’. Drugs that are currently used to lessen the risk of regurgitation include those to neutralize stomach acid, those to decrease acid production, and those to increase the downward emptying of the stomach.

If you are sick

In general, you should be as well as possible before undergoing any anaesthetic or surgery. Sometimes, of course, surgery is necessary and there may even be some degree of urgency to have the operation. Your surgeon, perhaps together with your anaesthetist, can weigh up your need for the operation and how urgent it is against any illness or condition you have. If you are scheduled for elective surgery, it is usual to delay the operation if you become unwell. In most cases, an optimal time will be suggested.

The final decision as to whether or not to delay your operation rests with your anaesthetist and your surgeon. It is best to contact them if you become unwell in the days leading up to your appointment. You may also wish to contact your family doctor for advice and possible treatment.

If you have a cold or the flu, it is likely that your anaesthetic and operation will be postponed. If you have a sore throat with no other symptoms, then your anaesthetist may consider that you can proceed, although your throat may be very sore afterwards. If the sore throat is an early sign of the development of a cold or the flu (and it isn’t always), then the resulting illness may be hastened and you may feel extremely unwell after the operation. Again, the decision to proceed rests with your anaesthetist and your surgeon, although if you decide not to proceed your wishes will be respected.

There is an increased probability of respiratory complications when anaesthesia is administered to a patient with an established cold or influenza. Your anaesthetist, however, is aware of the potential for complications and of the means of managing them safely. Diarrhoea is not a contraindication to anaesthesia or surgery unless it is part of a more generalised illness. One of the benefits of the developments in anaesthetic drugs and techniques is that anaesthesia is now relatively safe, even in patients who are severely ill.

In the Operating Room

If general anesthesia is used, the anesthesiologist will start transitioning you from the normal awake state to the sleepy state of anesthesia. This is called induction, which is usually done by either injecting medicine through an IV or by inhaling gases through a mask.

If, like lots of people, you’re afraid of needles, the good news is that you may not have to get one while awake. Anesthesiologists often will begin the induction process by using a breathing mask to help you relax. The mask delivers medication to make you sleepy before and during the surgery. That way, you won’t be awake when the IV is inserted for general anesthesia or when a shot is given to numb a certain part or area of the body for local or regional anesthesia.

When using general anesthesia, the anesthesiologist will monitor your vital signs, continue to deliver anesthesia, and keep you as comfortable as possible throughout the operation.

To help you breathe and/or to help deliver general anesthesia during the operation, the anesthesiologist might use an endotracheal tube (a plastic tube that’s placed into the windpipe through the mouth or nose) or laryngeal mask airway (or LMA — a mask with a tube that fits into the back of the mouth).

After Surgery

Once the operation or procedure is over, you’ll be taken to the recovery room or PACU (post-anesthesia care unit). In the PACU, nurses and the anesthesiologist will monitor your condition very closely to make sure you are making a smooth and comfortable transition from an anesthetized state to an awakened state.

If you had general anesthesia or were sedated, don’t expect to be fully awake right away — it may take a while and you may doze off for a bit. It usually takes about 45 minutes to an hour to recover completely from general anesthesia. In some cases, this period may be a bit longer depending on medications given during or after surgery.

Although every person has a different experience, you may feel groggy, confused, chilly, nauseated, scared, alarmed, or even sad as you wake up. Depending on the procedure or surgery, you may also have some pain and discomfort afterward, which the anesthesiologist can relieve with medications. When you have recovered from the anesthesia, you’ll be evaluated to make sure you’re ready to leave the recovery room.

In many outpatient procedures, people are allowed to come home soon after the surgery is done. Before you leave the hospital, you’ll receive instructions for further recuperation at home and for a follow-up visit with the surgeon. Talk to the surgeon and/or the anesthesiologist about what to expect after the surgery and how you can stay as comfortable as possible.

Anesthesia is very safe. In today’s hospitals and surgery centers, highly trained professionals use a wide variety of modern medications and extremely capable monitoring technology to ensure that people are stable and as comfortable as possible before, during, and after their procedure.

Anesthesia drugs

Infiltrative anesthetics (for Local and Regional Anesthesia, sometimes in General Anesthesia for pain relief post op)

Infiltrative anesthesia is often administered in the office setting for local anesthesia.

There are two classes of infiltrative anesthetics, amides and esters, which create a reversible blockade of sodium channels within the nerve fibers 3. When choosing an anesthetic agent, it is important to consider the type of procedure, the length of time required for anesthesia, and the pharmacodynamics of each medication. Table 1 is an overview of commonly used infiltrative anesthetic agents 4. True allergies to local anesthetics are rare, especially with amide preparations 5. However, evidence suggests there is cross reactivity between agents within the same class 6. In patients with a possible allergy, skin testing should be considered when immunoglobulin E–mediated reactions cannot be ruled out using the history 7.

Anesthetic Agents

Lidocaine (Xylocaine), an amide, is the most commonly used infiltrative anesthetic and is available in several concentrations 5. For most procedures, a 0.5% or 1% solution is appropriate. Higher concentrations of lidocaine do not improve onset or duration of action and may increase the risk of toxicity 8. Adding epinephrine (concentration of 1:100,000 or 1:200,000) prolongs the duration of anesthesia, increases the maximum dose, and may aid hemostasis 9. Contrary to longstanding belief, the use of lidocaine with epinephrine on the nose, ears, digits, and penis appears to be safe 10, 11. However, many physicians still choose to avoid epinephrine use in these areas. Epinephrine should not be used in patients with peripheral artery disease.

Bupivacaine (Marcaine) is a widely used amide. It has a prolonged duration of action, but this also increases the risk of toxicity (4:1 risk of toxicity compared with lidocaine) and can cause a dose-dependent widening of the QRS interval, leading to ventricular fibrillation 12. Bupivacaine is contraindicated in pregnant women because of the increased bio-availability from decreased venous return 13.

Procaine (Novocain) and tetracaine (Pontocaine) are most often used for dental, topical, spinal, and epidural anesthesia.

Table 1. Commonly Used Infiltrative Anesthetic Agents

AgentConcentrationOnset*Duration*Maximum dose
mg per kgmL

Amides

Lidocaine (Xylocaine)

0.5%, 1%, or 2%†

Rapid: < 2 minutes

30 to 60 minutes

4 (up to 300 mg per dose)

0.5%: 60 1%: 30 2%: 15

Lidocaine with epinephrine‡

1% or 2%

Rapid: < 2 minutes§

1 to 4 hours

7 (up to 500 mg per dose)

1%: 50 2%: 25

Bupivacaine (Marcaine)

0.25% or 0.5%

Slow: 5 minutes

2 to 4 hours

2 (up to 175 mg per dose)

0.25%: 70 0.5%: 35

Esters

Procaine (Novocain)

1% or 2%

Moderate: 2 to 5 minutes

15 to 60 minutes

7 (up to 600 mg per dose)

1%: 60 2%: 30

Tetracaine (Pontocaine)

0.5%

Slow: 5 to 10 minutes

2 to 3 hours

1.4 (up to 120 mg per dose)

24


*—Similar for all concentrations of each agent.

†—Higher concentrations provide no additional anesthetic effects.

‡—Epinephrine concentration may be 1:100,000 or 1:200,000.

§—May take up to 5 minutes for epinephrine to be effective.

[Source 14]

General anesthetic

A general anesthetic (or anaesthetic) is a drug that can bring about a reversible loss of consciousness. Anesthesiologist (or anaesthetist) administers these drugs to induce or maintain general anesthesia to facilitate surgery. Some of these drugs are also used in lower dosages for pain management. The biological mechanisms of the action of general anesthetics are not well understood.

Mode of administration. Drugs given to induce general anesthesia can be either as gases or vapors (inhalational anesthetics) or as injections (intravenous anesthetics or even intramuscular). It is possible to deliver anesthesia solely by inhalation or injection, but most commonly the two forms are combined, with an injection given to induce anesthesia and a gas used to maintain it.

Inhalation general anesthetic

Inhalational anaesthetic substances are either volatile liquids or gases, and are usually delivered using an anesthesia machine. An anesthesia machine allows composing a mixture of oxygen, anesthetics and ambient air, delivering it to the patient and monitoring patient and machine parameters. Liquid anesthetics are vaporized in the machine. All of these agents share the property of being quite hydrophobic (i.e., as liquids, they are not freely miscible—or mixable—in water, and as gases they dissolve in oils better than in water).

Many compounds have been used for inhalation anaesthesia, but only a few are still in widespread use.

  • Desflurane, isoflurane and sevoflurane are the most widely used volatile anaesthetics today.

They are often combined with nitrous oxide. Older, less popular, volatile anaesthetics, include halothane, enflurane, and methoxyflurane. Researchers are also actively exploring the use of xenon as an anaesthetic.

Injection general anesthetic

Injectable general anesthetics are used for the induction and maintenance of a state of unconsciousness. Anaesthetists prefer to use intravenous injections, as they are faster, generally less painful and more reliable than intramuscular or subcutaneous injections.

Among the most widely used drugs are:

  • Propofol
  • Etomidate
  • Barbiturates such as methohexital and thiopentone/thiopental
  • Benzodiazepines such as midazolam
  • Ketamine is used in the UK as “field anaesthesia”, for instance at a road traffic incidents or similar situations where an operation must be conducted at the scene or when there is not enough time to move to an operating room, while preferring other anaesthetics where conditions allow their use. It is more frequently used in the operative setting in the US.

Benzodiazepines are sedatives and are used in combinations with other general anesthetics.

Anaesthetic equipment

Some of the drugs given by the anaesthetist are injected, but others are inhaled. To deliver these inhaled drugs, as well as oxygen, your anaesthetist uses an anaesthetic machine.

The anaesthetic machine is not a machine that makes anaesthetics, but a complex collection of equipment. It has three major components: a gas mixing and delivery system; an anaesthetic breathing system ( circuit) and a ventilator; and an array of monitors. Some recently developed machines have highly complex integrated electronic systems and are usually called anaesthesia workstations.

The gas mixing and delivery system

The anaesthetic machine is connected to a supply of purified gases. These gases usually include oxygen and nitrous oxide, and many machines also have a supply of compressed air. All the gases are mixed in a special device, which ensures accurate concentrations and limits the minimum amount of oxygen which can be used. To this gas mixture, the anaesthetist can add one of a range of additional, more powerful anaesthetic agents, known as inhalational agents. These come as a liquid and are placed in a device called a vaporiser, which converts them into a gas and adds them in carefully controlled concentrations to the gas mixture.

The anaesthetic breathing system (circuit) and ventilator

The anaesthetist determines the flow rate of the final mixture of gases supplied to the breathing system. This is a series of hoses about three centimetres in diameter, which connects to either the mask or the endotracheal tube, but also to a ventilator. The breathing circuit is often attached to a container of ‘soda lime’ granules: these absorb carbon dioxide that the patient exhales with each breath.

The ventilator is an automatic breathing device, which takes over the rhythmic inflating and deflating of the patient’s lungs in a programmed manner. The anaesthetist sets the gas flow, the oxygen concentration, the anaesthetic agent concentration, the amount of gas in each breath, and the number of breaths per minute.

The monitors

Some people think that anaesthetists do not do anything during an operation, once the anaesthetic has started. In fact, anaesthetists are very busy, watching and evaluating their patients, the progress of the operation, the surgeon, and all the other members of the Operating Room team. By watching and evaluating – or processing all this information – your anaesthetist is able, if necessary, to make moment-by-moment adjustments to the drugs and fluids that you need during your anaesthetic and operation. Your anaesthetist is also able to consider the plan for the next phases of your care, such as in the recovery room.

Some of the information that your anaesthetist evaluates comes from special monitors. Two kinds of monitors are used to make continuous checks. One kind tells your anaesthetist all about you, including include your heart rate, blood pressure, and temperature. The other kind shows how the anaesthetic machine is functioning.

Measurements of how your body is reacting to the anaesthetic and operation or examination include:

  • Your heart rate (pulse) and rhythm: by feeling the pulse in your wrist or your neck, by using a stethoscope to listen to your heart, and by means of the electrocardiograph (ECG or EKG). The same monitor can also be used to detect if your heart is suffering any strain.
  • Your (arterial) blood pressure: by attaching a traditional inflatable cuff or sometimes by inserting a small tube or cannula (or catheter) directly into an artery.
  • The amount of oxygen in a small or peripheral artery: by attaching a device like a clothes-peg, known as a pulse oximeter to one of your fingers or toes or ear lobes, or to the tip of your nose. The result is known as your arterial oxygen saturation.
  • The amount of carbon dioxide (CO2) you breathe out: by using a carbon dioxide detector. The result is known as your end-tidal (end of each breath) carbon dioxide concentration. This measurement helps your anaesthetist to check on the function of your lungs and on your metabolism. This monitor is also used to ensure that the breathing tube is correctly placed in your windpipe or trachea and that the breathing circuit has not become disconnected.
  • How well you are breathing (or being breathed for): by using a stethoscope, so that your anaesthetist can ensure that your breathing tube is not inserted too deeply and that you do not have any areas of blockage in your lungs. Other methods to measure the adequacy of your breathing include the use of a special meter to assess the size or volume of each breath you take or are given, and a gauge to measure the pressure in your lungs between breaths and the pressure that is required to inflate your lungs with each breath.
  • Your nerve and muscle function: by using a peripheral nerve stimulator to check how the muscle relaxants are affecting your muscle activity and power.
  • Your temperature: by using a thermometer, to ensure that you don’t get too hot or too cold, since you lose some of your ability to control your temperature while anaesthetised.
  • How much urine you are producing: by inserting a catheter into your bladder during some operations and examinations. This allows your bladder to drain freely and also gives your anaesthetist an idea of how well your kidneys are functioning.
  • The pressures in your large veins and your heart: by inserting a special cannula into a large vein in either your neck or arm and passing the cannula through into the large blood vessel (superior vena cava) that leads to the heart. Sometimes the cannula is actually threaded through the chambers of the heart and into your pulmonary artery (which carries blood to the lungs.) As well as pressures, the cannula can determine how much blood your heart is pumping with each beat.
  • The depth of your anaesthetic, and whether or not you are unconscious (if you are having a general anaesthetic): by using a monitor that looks at small electrical impulses or ‘brain waves’ generated by the brain. (This is similar to an ECG of the brain.)This last monitor is not available in many centres. Currently most anaesthetists do not have access to a monitor that indicates if you are adequately anaesthetised or aware of your surroundings. This kind of monitor is still under development. But current anaesthetic practice is different from that of say, ten years ago, in that your anaesthetist can now measure with an anaesthetic agent monitor exactly how much anaesthetic agent you are receiving. This measurement tells your anaesthetist that you are receiving enough anaesthetic gas to ensure that you are unconscious.Your anaesthetist also constantly observes a number of measurements from the anaesthetic machine. These include:
    • the pressure of oxygen and nitrous oxide in the pipelines or tanks on the back of the machine from which these gases are delivered
    • the amount of oxygen flowing to you from the machine
    • the number of times each minute that the breathing machine (or ventilator) delivers a breath to you
    • the amount or concentration of anaesthetic agents in the gas you breathe in and out
    • that you are still connected to the breathing circuit, and that this circuit has not become disconnected.

This last observation is vital, because you may have been given drugs which stop you from breathing. If so, then you must remain connected to the breathing circuit to make sure that you continue to receive oxygen. If your breathing circuit becomes disconnected, you could suffer brain damage or death if the disconnection is not detected in time.

Specialty societies and regulatory bodies in anaesthesia have published guidelines describing the equipment and monitors necessary to provide anaesthetic care.

Examples are:

One function of these guidelines is to provide details of the absolute minimum type and number of monitors that should be present, functioning, and used before an anaesthetic is given. This is similar to the ‘Minimum Equipment List’ required in aviation before a pilot can take off.

By now you should also have an idea of the amount and complexity of information that your anaesthetist must constantly observe and monitor. Currently there is no ‘black box’ like the one used in aviation that can integrate all the measurements and provide a ‘flight profile’ for your anaesthetic and operation. Some new anaesthetic machines do incorporate automated record-keeping systems, which help to document and integrate some of this information. Automated systems offer advantages in that a record can be kept during emergencies when the anaesthetist may be very busy (as described later).

Another similarity with aeroplanes is that the anaesthetic machine also has self-checking and monitoring capabilities, so that problems can be easily identified. There is also always a back-up system, so that if the system fails, or there is a power blackout, the anaesthetist can safely carry the patient through such a crisis. In many ways the anaesthetist is indeed like a pilot, flying the plane, watching the instruments, and looking out the window (at the surgeon), always ready to take control if a problem occurs. This concept is also emphasised in the equipment guidelines mentioned above. In addition to listing pieces of equipment, these documents also recommend that the most important monitor of the anaesthetised patient is the continuous presence of an anaesthetist.

Anesthesia Recovery

After your operation or procedure, you are taken to one of several places. Most commonly, this is the recovery room (RR) where there are a number of other patients (depending on the size of the facility) also recovering from their anaesthetics. Other names for this area include the Post-Anaesthetic Recovery Room (PARR) or the Post-Anaesthesia Care Unit (PACU).

If you have undergone a very minor procedure, usually not involving an operation, and in a small surgical clinic or X-ray facility, you may be taken to a recovery ‘bay’ or place for a single patient. Your care should be the same as you would receive in a Recovery Room.

If you have only a local anaesthetic or monitored anaesthesia care, you might be discharged directly to the day care ward – for example, after cataract surgery under nerve block. Either your surgeon (in the case of local anaesthesia) or your anaesthetist makes this decision, on the basis of your being stable after the procedure and well recovered from any drugs which you have received.

If you were very ill before surgery, or you had major or complicated surgery (for example, open heart surgery), or complications arose during the course of anaesthesia or surgery, then you might be transferred to an intensive care unit (sometimes known as Intensive Therapy Unit) or high dependency unit. (These units are often referred to by their initials: ICU, ITU or HDU.) They offer a more highly specialised level of nursing and medical care.

When you are transferred to the Recovery Room, your anaesthetist provides the Recovery Room nurse with a brief report. This will include a description of:

  • your preoperative condition, including any medical illnesses and medications
  • the surgical procedure
  • the course of the anaesthetic, including any problems with your airway, any need for airway control in the Recovery Room, and the adequacy of recovery of muscle strength
  • intravenous cannulae
  • intraoperative fluid balance ( how much intravenous fluid you were given and how much fluid you lost, including blood loss)
  • any other important information.

While this description is being given, the nurse usually places an oxygen mask over your face to give you extra oxygen, and attaches a blood pressure cuff and a pulse oximeter. You may or may not be conscious at this stage. If you are not, then you will probably be positioned on your side, which may become a little uncomfortable as you awaken. This position, known as the ‘coma position’, is commonly used in any situation where a person’s ability to protect his or her airway may be weakened. In this position, the tongue falls forward, rather than backwards where it may obstruct breathing. In addition, if the person were to regurgitate or vomit, the vomitus would drain away from the mouth and not be sucked into the lungs.

You may still have a plastic airway or breathing tube in place. Exactly when this tube is removed depends in part on your condition and why the tube was inserted, and also on how conscious you are. Your anaesthetist might choose to remove the tube while you are still in the Operating Room. If you are still deeply unconscious when you arrive in the Recovery Room, your anaesthetist might leave the tube in until you ‘lighten’ or regain consciousness. (The process of removing the tube is known as extubation.) To many people, the thought of having a breathing tube in place while awake sounds unpleasant. However, what anaesthetists consider to be ‘awake’ in the Recovery Room is not quite the same as being fully conscious. In fact, being able to open the eyes and mouth and to take a breath on command are signs that you are probably awake enough to have the tube removed. Most patients do not remember any of this.

Once your anaesthetist is confident that your vital signs are stable and that your safety is assured, the process of ‘transfer of care to the Recovery Room nursing staff’ occurs. This means that the nurses are now responsible for your care and your anaesthetist may leave you to return to the Operating Room to start the anaesthetic for the next patient on the surgical list.

Who will look after you ?

The Recovery Room provides specialised nursing staff that has specific training in the management of common problems of partially anaesthetised patients. Following general anaesthesia, patients in the Recovery Room may develop difficulty breathing. For example, after tonsillectomy, there is always the risk of swelling and bleeding from where the tonsils were removed, making it more difficult for patients to breathe. cardiovascular problems are also of concern. Low blood pressure ( hypotension) can occur because of blood loss or from blood pooling in the veins which dilate as body temperature is restored to normal. High blood pressure ( hypertension) may be due to pain, pre-existing hypertension, and an increased concentration of carbon dioxide in the blood or from having a full bladder. Common but less life-threatening problems include pain, nausea and vomiting. Usually your anaesthetist will leave orders for painkillers or analgesics, drugs to combat nausea and vomiting (anti-emetics), and intravenous fluids. These orders may be written after consultation with your surgeon, but your anaesthetist is the doctor in charge of your care in the Recovery Room.

What will I see ?

At first your vision is likely to be somewhat blurred. It is not uncommon to see more than one nurse or anaesthetist, despite the fact that only one is present at your bedside! Gradually you will be able to focus better. Although it is reassuring to be able to see clearly, many hospitals do not recommend that you take your glasses with you to the Operating Room. (This is because of the possibility that they might be mislaid or dropped while you were unconscious.) In that case, you would not be able to wear your glasses until you returned to the ward. Some hospitals do allow you to keep your spectacles with you.

If the hospital allows your relatives to be with you in the Recovery Room, it may be best to leave your spectacles with them. (Some hospitals do not allow any visitors in the Recovery Room.) If your child normally wears glasses, then it is a good idea to have them available, so that the Recovery Room nurse can give them to your child as he or she awakens.

What will I hear ?

In general, your hearing will not be significantly affected, although you may well forget instructions that are given to you during the early recovery period. Some people complain that sounds are louder than normal, but this is usually only temporary and is due to complex interactions between the various anaesthetic drugs and your hearing mechanism. A few patients may develop sudden loss of hearing in one or both ears after an anaesthetic and operation. One reason for this problem is the effect of pressure from the nitrous oxide on the eardrum and Eustachian tube (inside the ear). These patients may complain of pain and / or clicking and popping in the ear, like that which occurs in an aeroplane when climbing or descending. Very rarely, the mechanism of the hearing loss cannot be explained and hearing may or may not recover. However, this complication is extremely rare.

If you normally wear a hearing aid, you may choose to leave it in during the operation. This can be helpful if you have significant hearing loss and are having your operation under regional anaesthesia, when you might need to hear what your anaesthetist is saying to you. Other patients might choose not to wear their aids, especially if they fit loosely and do not provide good hearing. Some patients would prefer not to hear anything that goes on in the Operating Room or the Recovery Room and therefore leave the aids at their bedside.

What will I say ?

You may say all sorts of things, mostly related to your sense of disorientation or your surprise at being awake so soon. You may refer to pain or other discomfort, which can then be treated appropriately. Occasionally, patients say suggestive things to their medical or nursing staff, because the effect of the drugs is to temporarily remove some inhibitions. This is very uncommon, and if it does occur, it is always treated with discretion. This type of reaction lasts only a brief time and patients have no memory of the event. If relatives are present, they should not be concerned.

Will I be in pain ?

Your anaesthetist endeavours to ensure that you are as pain-free as possible at the end of your operation or procedure. This is not always easy to achieve. Some of the anaesthetic drugs provide some pain relief, but need to be stopped at the end of the anaesthetic so that you regain consciousness. A number of techniques are used to control postoperative pain, most being started during the anaesthetic. These techniques can be modified as necessary in the early postoperative phase in the Recovery Room, so that you have the maximum possible comfort. With some conditions, however, complete obliteration of pain may not be possible without risk of complications, especially where control of breathing may be affected.

Will I feel sick ?

You may feel nauseated and it is not uncommon for patients to vomit or ‘dry retch’ once or twice in the Recovery Room. Often this will bring up some mucous or bile-stained fluid, and is usually the only time that vomiting occurs, although some nausea may continue. Your anaesthetist may have given you some anti-emetic drugs during the anaesthetic if vomiting is thought likely to be a problem. Even if an anti-emetic has not already been given, it is not too late to administer some in the Recovery Room, and the nurse will arrange for it to be given.

Will I be cold ?

You may feel cold, and shivering is not uncommon in the Recovery Room. This is due partly to the fact that anaesthesia decreases the body’s ability to maintain a normal temperature, resulting in loss of body heat. Shivering is also due to some of the anaesthetic drugs that ‘switch on’ the shivering mechanism in the recovery phase.

In recent years, much more attention has been paid to ensuring preservation of body heat during surgery so that postoperative shivering is now less common. Devices such as warm water mattresses, warm air blankets, insulation wraps, and warmers for intravenous fluids and anaesthetic gases have contributed to this improvement.

Children in the Post-Anaesthesia Care Unit (PACU)

Children often go through a period of disorientation and restlessness which may be difficult to manage for a short time as they regain consciousness. This affects younger children more frequently and is quite normal, although rather distressing to parents or guardians. The reaction is more common after short procedures where there is minimal use of potent painkillers or other sedatives. The restlessness may be prevented or treated by the use of sedatives, either at the time or given as premedication. However, the effect of any of these drugs is to prolong recovery time significantly. If this type of distress has been a concern on previous occasions or with siblings, you should discuss the management with your child’s anaesthetist.

Children are frequently able to drink while still in the recovery room. Usually babies can be breast-fed, unless there is some particular reason to not do so.

In most modern surgical suites it is usual to allow parents to sit with their children as they awaken from anaesthesia. You may be encouraged to do so, once the nurse caring for your child is satisfied that all vital signs are stable and recovery is proceeding normally. You should ask your hospital or anaesthetist as to whether or not they allow this practice.

Some young children do not wake easily after an anaesthetic, especially if the anaesthetic coincides with the child’s normal sleep pattern. This is more likely if the recovery phase coincides with the child’s usual bedtime and if the child is normally a heavy sleeper. The situation may be quite disturbing to parents, but is quite normal. The use of painful stimulation to ‘wake the child up’ is discouraged.

Discharge from Post-Anaesthesia Care Unit (PACU)

Anaesthetists and nurses use specific criteria to determine if a patient is fit enough to be discharged from the recovery room. A patient must:

  • be able to breathe properly without assistance
  • have stable vital signs (for example, blood pressure and heart rate)
  • be awake (except children, see separate section) and orientated

If there is any bleeding from the surgical site, it should be well controlled and minimal.

In general, when a patient meets all these criteria, the nurse may discharge the patient from the Recovery Room without the anaesthetist being present. However, some patients require review by their anaesthetist, even if they meet the discharge criteria. Other patients might not meet the criteria, despite having spent what appears to be an appropriate length of time in the Recovery Room. This might be because of complications from the operation or anaesthetic, or from problems with pre-existing conditions. These patients might require further consultation (e.g. by a cardiologist or referral to an HDC or ICU).

The nurses are responsible for maintaining a record of the patient’s condition in the Recovery Room. They are also responsible for conveying relevant information to the ward, unit or clinic to which the patient is to be transferred. Depending on the operation, most patients stay for a minimum of 30 minutes in the Recovery Room, although this time may be increased to a few hours if the patient has undergone a very complex operation. Occasionally patients may have to stay longer in the Recovery Room, although they are ready for discharge because of administrative problems within the hospital, such as a lack of nurses or porters to transport the patient, or a lack of beds on the ward.

Back on the ward

After discharge from the recovery room, you are transported to a ward. This may be a regular ward, where you will spend at least one night. The length of time spend in the hospital ward varies according to the severity and length of your operation, and to a certain extent the complexity of anaesthesia.

Alternatively, you may be taken to a day ward, where you spend only a few hours before going home. Many procedures (up to 70 per cent in some countries) are now performed on a day-stay basis, with the patient staying in the hospital or clinic for less than 24 hours. Not all procedures are suitable for discharge home so soon, especially major operations involving surgery on the brain, or within the chest or abdominal cavities, or surgery requiring continuous intravenous or epidural pain relief, such as after total hip replacement.

No matter how long you stay, the nurses will ensure that you are continuing to follow the expected course of recovery from your anaesthetic and operation.

Postoperative pain relief

The management of postoperative pain is a continuation of the pain control provided during your anaesthetic. Both your anaesthetist and your surgeon may be involved in prescribing the drugs used for relieving your pain.

There are several options for postoperative pain control, which can be distinguished by the route or manner by which these drugs are given. These options include the following.

  • Oral or rectal analgesics and anti-inflammatory drugs

These drugs include paracetamol or acetaminophen (alone and with codeine), codeine phosphate, anileridine, tramadol, buprenorphine, indomethacin, and ketorolac. Most of them are taken as tablets, although a syrup may be used for children. Many of these drugs may also be given as suppositories. They are used for mild to moderate pain and are suitable for patients who are staying in hospital after minor operations or who are to be discharged home the day of the operation. These drugs have few common side effects, apart from constipation with codeine and the risk of reduced breathing if an overdose of anileridine is taken. There have been a few rare cases of sudden onset of kidney failure in patients who have been given ketorolac, although the evidence proving such a link is not clear.

  • Intramuscular injections

Most often this route is used for the administration of opiate or narcotic analgesics. These are given on an intermittent basis, usually every few hours. A typical order would be ‘ morphine 10 mg im q4h prn’ (which translates to ‘give 10 mg of morphine intramuscularly every four hours – but no sooner – if the patient wishes it’). This technique provides adequate, but not very good, pain control. Shortly after receiving the injection, the patient gets the effect of a large amount of drug, which may reduce breathing and produce sedation and even confusion. Then the effect of the drug wears off, leaving the patient in pain until the next injection. The use of intramuscular injections is declining in popularity, not only because continuous administration methods provide better pain control, but also because of the discomfort of the injection.

  • Continuous intravenous infusion

With this technique, opiates or narcotics are delivered directly via an intravenous cannula at a predetermined rate. This provides a steady concentration of drug in the bloodstream (in contrast to the intramuscular technique which gives a variable blood concentration). Nursing or medical staff may adjust the rate of infusion, according to the pain relief obtained.

  • Continuous subcutaneous infusion of analgesics

This is similar to the intravenous method, except that the fluid is pumped through a fine needle into the tissues just under the skin, usually on the abdomen. Because the volume of fluid is small, there is little swelling or discomfort and the drug is well absorbed.

  • Patient controlled analgesia (PCA)

This is another method of intravenous injection of opiates or narcotics, except that the patient controls the analgesia by pushing a button to determine when the injection is given. The administration of the drug is determined by a pump that has been programmed to deliver a fixed, safe dose of drug every time the patient requests it. There is a maximum hourly dose and a ‘lock-out’ interval that can be adjusted to prevent overdose. (This is similar to bank machines, which have limits on withdrawals.)

This technique is based on the principle that if the patient who has become sleepy will not push the button until the effect of the drug wears off. Of course, this principle requires that only the patient, and not a friend or family member, pushes the PCA button. Often anaesthetists are in charge of programming these pumps, although surgeons or specially trained nurses may also do so. If necessary, the dose and timing of the drug may be adjusted by reprogramming. Drugs commonly administered by this method include morphine, pethidine ( meperidine), and fentanyl. Some doctors also prescribe a constant infusion (or a ‘background infusion’) of a small amount of drug, so that there is always some pain relief present. However, this technique carries a greater risk of reduction of breathing, than does the ‘demand’ technique alone, although it is useful in certain patients with extreme pain.

  • Spinal narcotic injection

Some anaesthetists like to add a small amount of an opiate or narcotic when they inject local anaesthetic into the spinal at the time of the operation. This can provide very good pain relief. For example, a woman having a caesarean section might not need any other pain medication after the operation if she has received some spinal (‘intrathecal’) opiate or narcotic.

  • Spinal or epidural infusions

Continuous infusions of local anaesthetics and/or narcotic analgesics into the spinal fluid or epidural space may be given for several days after surgery. The advantage with this technique is that there is little sedation, compared with other methods. These methods are particularly useful for patients undergoing chest operations (thoracotomies) or upper abdominal operations, or major orthopaedic surgery to the hips and legs. These operations are painful and most patients require large amounts of intramuscular opiates or narcotics to provide adequate pain relief, with the possible risk of reduced breathing. The use of an epidural or spinal means that the patient can actually be pain-free.

  • Nerve blocks

In addition to general anaesthesia, some anaesthetists like to perform a nerve block – to provide analgesia (pain relief) of the area in which the operation or procedure is to take place. This is commonly done for children undergoing circumcision (with a penile nerve block) or hernia repair (with a caudal anaesthetic). Some anaesthetists believe that blocking pain nerves before the patient has any pain actually decreases the amount of pain relief required. This is termed ‘pre-emptive analgesia’.

Two other important points must be made about pain management. The first is the role of the acute pain Service (APS). In the 1970s, researchers began to investigate different methods for the relief of postoperative pain. Then in the 1980s, anaesthetists started to apply this knowledge to improve pain relief. These methods included all those described above. Use of these different techniques has varied widely between institutions; however, most large anaesthetic departments provide a postoperative analgesia service (or Acute Pain Service). Successful programmes rely on the assistance of dedicated, specially trained nursing support.

The other important point about pain management is that all patients who receive opiates or narcotics are at risk of reduced breathing. Some patients need to be looked after in special care units, not only because of the narcotics but for other medical or surgical reasons. Other patients require frequent monitoring, but can be cared for with regular nursing.

Are there other methods of pain relief ?

There are other methods of pain relief that do not involve the administration of drugs. These ‘non-pharmacological’ methods include:

  • Application of warmth: Heated gel or beanbag pads may be used, as may infrared lamps. Great care must be taken to avoid burning the skin, especially in the elderly and those with fragile skin or poor circulation. Lamps, in particular, should only be used for a short time.
  • Distraction: This is a method of pain relief which is useful in patients of all ages, but particularly in children. The idea is to concentrate the mind on something other than the pain. This can be done by reading, doing puzzles, story-telling, looking out a window at a busy street, and even watching television.
  • Relaxation: Three ways of relaxing and reducing the psychological awareness of pain are listening to music, meditating, and having a massage.

Anesthesia risks

Anesthesia today is safer than in the past, complications do occur. In very rare cases, anesthesia can cause complications (such as strange heart rhythms, breathing problems, allergic reactions to medications, and even death). One large study showed that about 10 per cent of patients experienced some problem during or after the anaesthetic. The complication could be as major as brain damage (but extremely rare) or as minor as muscle soreness (but more common). The most frequent complications are nausea, vomiting and sore throat. Anaesthetists are trained to recognise and manage complications quickly, and many will undergo part of this emergency training in simulators, much like airline pilots do.

The likelihood of a complication occurring is proportional to a variety of factors related to the patient’s health, the kind of procedure (complexity of the surgery being performed) and the type of anesthesia used. Be sure to talk to your doctor, surgeon, and/or anesthesiologist about any concerns.

The accompanying lists describe some of the complications that may occur during or after an anaesthetic. This lists are selective and do not include all complications.

Most complications can be prevented by giving the anesthesiologist complete information before the surgery about things like:

  • your current and past health (including diseases or conditions such as recent or current colds, or other issues such as snoring or depression)
  • any medications (prescription and over-the-counter), supplements, or herbal remedies you are taking
  • any allergies (especially to foods, medications, or latex) you may have
  • whether you smoke, drink alcohol, or take any recreational drugs
  • any previous reactions you or any family member has had to anesthesia

To ensure your safety during the surgery or procedure, it’s extremely important to answer all of the anesthesiologist’s questions as honestly and thoroughly as possible. Things that may seem harmless could affect how you react to the anesthesia.

It’s also important that you follow the doctor’s recommendations about what not to do before the surgery. You probably won’t be able to eat or drink (usually nothing after midnight the day before) and may need to stop taking herbal supplements or other medications for a certain period of time before surgery.

You can rest assured that the safety of anesthetic procedures has improved a lot over the years, thanks to advances in technology and the extensive training anesthesiologists receive. The more informed, calm, and reassured you are about the surgery and the safety of anesthesia, the easier the experience will probably be.

Anesthesia side effects

Common Side Effects of Anesthesia

You will most likely feel disoriented, groggy, and a little confused when waking up after surgery. Some other common side effects, which should go away fairly quickly, include:

  • nausea or vomiting, which can usually be alleviated with anti-nausea medication
  • chills or shakiness
  • sore throat (if a tube was used to help with breathing)

Complications during anaesthesia

Allergy

Allergy to anaesthetic drugs is rare. The severity of allergic responses can range from mild (wheeze and rash) to severe (life-threatening anaphylactic reactions). As well as anaphylactic or immune-related reactions, some patients develop anaphylactoid reactions. Although this type of reaction does not involve antibodies, these reactions may also be severe, through the release of histamine.

If a patient is undergoing a general anaesthetic and is unconscious, the signs of an anaphylactic reaction may vary. The diagnosis is made by the recognition of such things as low blood pressure, wheezing, hives, rash, swelling (oedema) around the eyes or in the mouth and throat, and breathing difficulties.

Anaesthetists are trained to recognise and treat allergic reactions in the Operating Room. However, an important part of treatment of any allergic reaction is prevention. If you have any history of swelling of the face or generalised itching, you should let your anaesthetist know. Skin testing can be used to identify allergens (substances that cause allergic reactions). This may be helpful in identifying the particular drugs causing a reaction in those patients who apparently are ‘allergic to anaesthesia’.

The prevention of latex allergy includes removing all latex containing materials from the Operating Room, where possible. Most Operating Rooms have a special equipment kit for use in caring for latex-allergic patients.

Adverse drug reactions

Some patients may react abnormally to one or more drugs used during anaesthesia. Usually there will be some warning of this from prior experience, or knowledge of the particular condition or health of the patient. Occasionally, however, there is little warning, and the anaesthetist must be constantly alert to the potential for abnormal reactions.

Some patients develop complications because of the interaction of specific anaesthetic drugs with a pre-existing condition. There are very few ‘anaesthetic diseases’, that is, specific diseases for which anaesthetic drugs must be carefully selected so as to minimise the risk of problems. However, these diseases do exist. The following brief description of two of these conditions is not meant to replace a more definitive source of information.

Malignant hyperthermia or malignant hyperpyrexia

Malignant hyperthermia or malignant hyperpyrexia consists of an unexplained rise in body temperature and muscle rigidity during anaesthesia, due to a massive increase in metabolism. Consumption of oxygen and production of carbon dioxide also rise markedly. Predisposition to malignant hyperthermia is an inherited condition and occurs in about 1 in 40,000 patients. Malignant hyperpyrexia is triggered after exposure to specific anaesthetic drugs – the volatile anaesthetic agents (such as isoflurane) and suxamethonium. Triggering may occur on the first exposure to these drugs or even after repeated and uncomplicated anaesthetics.

Treatment of an episode of malignant hyperpyrexia consists of stopping the triggering drug, stopping the operation if possible, and administering a drug called dantrolene. This is the only specific drug treatment for this syndrome; without it, about half of all patients who suffer a malignant hyperthermia reaction will die. Other treatment is also important, in the form of extra oxygen, cooling, and resuscitative drugs and fluids.

The principal test for malignant hyperpyrexia is one performed on a piece of biopsied muscle, although unfortunately some tests appear to show that the patient has the condition when in fact the patient does not. (This is known as a ‘false positive’ test result.) As more genetic patterns are recognised in families with malignant hyperpyrexia, some susceptible patients may be diagnosed using genetic marking. The patient and close relatives should all be tested. A patient who has had an malignant hyperpyrexia reaction or a positive test should obtain some form of Medic Alert notification and carry this at all times.

If a patient with known malignant hyperpyrexia requires an operation, then the Operating Room should be specially prepared. No volatile anaesthetic agents should be used in the room for 12 hours and, if possible, the patient should be scheduled as the first case of the day. A ‘safe’ technique consists of avoiding the known triggering agents and is not difficult to achieve. Drugs that are considered ‘safe’ include nitrous oxide, thiopentone, propofol, midazolam, narcotics, muscle relaxants such as curare or vecuroniun, and any of the local anaesthetic drugs. The patient’s condition, including temperature, should be carefully monitored as with any general anaesthetic. This monitoring should continue into the postoperative period. Some patients have been reported to have a reaction after a ‘safe’ anaesthetic, but these reactions apparently have not been severe.

Plasma cholinesterase deficiency

Plasma cholinesterase deficiency or pseudocholinesterase deficiency (PChD) is an enzyme deficiency that affects the metabolism of some anaesthetic drugs, thus lengthening their action. These drugs include certain types of local anaesthetic agents and suxamethonium. It is important to remember that having PChD does not mean that the patient is ‘allergic’ to these drugs, but simply that the drug takes longer to wear off.

If a patient with PChD is given suxamethonium, then the muscle relaxation from the drug may last for several hours, instead of a few minutes. During this time, the patient is unable to move or breathe spontaneously, and requires artificial ventilation. sedation, which makes the period of the profound weakness less unpleasant, is used while the action of the drug wears off.

PChD may be inherited and is found in less than 0.01 per cent of the population. The condition may also occur in patients with liver failure and certain tumours, as well as in those exposed to specific drugs, such as ecothiopate, and to certain insecticides. Some women at the end of pregnancy may develop a very mild form of PChD which disappears after birth of the baby. The enzyme deficiency can be confirmed by a special blood test.

Heart attack or stroke

It is possible to suffer a heart attack during the course of an anaesthetic. However, if one does occur, it is more likely to be on the second or third day after the operation. The risk of having a heart attack or myocardial infarction (MI) is very low, but patients who have suffered an MI in the past should consider not having elective surgery during the following six months.

Other patients with severe hardening of the arteries of the neck (carotids) are not only at risk of myocardial infarction, but also of a stroke (cerebro-vascular accident or CVA). Again, this is a rare but serious complication of anaesthesia.

Obstructed breathing

  • Laryngospasm

Sometimes, especially at the beginning or end of an anaesthetic, the vocal chords in the larynx (voice box) may close, making it very difficult for any air or oxygen to pass to and from the lungs. The condition can be likened to “choking”, and if allowed to continue, can result in a lack of oxygen entering the bloodstream. Anaesthetists are trained to deal effectively with this potentially serious complication, sometimes requiring the emergency administration of drugs to relax all muscles.

  • Difficult airway

Some patients have particular anatomical features of their neck and mouth that make management of their airway, or intubation difficult. The anaesthetist will make a judgement as to the likelihood of such a problem, during the pre-anaesthetic assessment. If he or she suspects that there may be a difficult airway, the anaesthetist will ensure that additional specialised equipment and expert assistance is immediately available.

  • Bronchospasm

Bronchospasm refers to a narrowing of the major airway branches in the lung. The result is similar to severe asthma with wheezing. When it occurs, the flow of air is reduced, especially when breathing out (exhaling). Commonly, bronchospasm is easily treated by deepening the anaesthetic, removing the stimulus, or giving drugs such as salbutamol, aminophylline, or steroids. For particularly severe reactions, adrenaline may be required.

Patients with asthma or chronic obstructive lung disease (COPD) and smokers may develop wheezing or bronchospasm. Bronchospasm may also occur in previously healthy patients during an allergic reaction due to drugs or blood products or after aspiration of gastric contents. Bronchospasm may also occur after such procedures as insertion of the breathing tube.

  • Pneumothorax

In this condition, air (or another gas) enters the normally empty space between the lungs and the chest wall. If not detected and treated, this can be life threatening as the gas expands and compresses the heart and the major blood vessels in the chest, preventing blood from entering or leaving. Most often a patient has a small but undiagnosed leak in the lining of the lung. This leak increases with the use of artificial ventilation. The problem may occur spontaneously in those with congenital swellings (bullae) of the lungs, patients with chronic lung disease and emphysema, or in asthmatics. In addition, the lining of the lung may be accidentally punctured by some injections around the neck or in the chest region.

Complications after anaesthesia

Nausea and vomiting

Postoperative nausea and vomiting is one of the most common postoperative complications, affecting up to as many as 40 per cent of patients. The patient most likely to vomit is a young, non-smoking, overweight woman who has undergone gynaecological surgery. Also at risk are patients with a history of postoperative nausea and vomiting and those with a history of motion sickness (in a car or aeroplane or at sea).

All anaesthetic agents have been blamed, with opiates or narcotics most often implicated. Indeed, the anaesthetic is most often blamed for all postoperative nausea and vomiting, even when nausea and vomiting occurs days after the operation and all traces of the anaesthetic have disappeared from the body.

Other factors may contribute, including:

  • preoperative conditions, such as vomiting, increased pressure in the brain, intoxication with alcohol or other drugs
  • operations on the eyes, the inner ear, the testicles, or tonsil
  • postoperative conditions, such as the presence of blood in the stomach (which no anti-emetic can counter) or blockage of the bowel
  • pain and anxiety
  • the presence of other vomiting patients or the smell of food
  • rapid movement (as on a stretcher) or even slight elevation of the head from the pillow
  • painkillers given during the anaesthetic or in the postoperative period.

Many of these factors can be avoided or treated, to reduce the chance of postoperative nausea and vomiting occurring. Your anaesthetist makes all attempts to ensure that you do not suffer from postoperative nausea and vomiting. However, complete prevention of this complication is not possible.

Dental damage

Although anaesthetists are very careful to avoid contact with the teeth, damage may occur when metal or hard plastic instruments are used to maintain an open airway, to help with insertion of the breathing ( endotracheal) tube, or to suck out secretions from the mouth and back of the throat. In most cases, damage occurs at the time of tracheal intubation, in about one in every 1000 intubations. Dental damage may also occur when a patient bites down on an oral airway during recovery from anaesthesia. The force generated is enough to break both natural and restored teeth and has been noted in between a quarter and a half of all reported cases of dental damage.

Although human teeth are very strong, they become more brittle with age. Just as you may chip a tooth while eating, the same may occur during intubation. Cosmetic dental work, with veneers, crowns or bridges, is a particular concern, as these structures are not as strong as natural teeth.

If you have had dental work, especially on your front teeth, then you should inform your anaesthetist and discus any concerns you might have. You should also point out any teeth which are loose. You may be able to lessen the risk of damage by having an alternative technique to general anaesthesia, such as regional anaesthesia (if appropriate). However, in some cases, general anaesthesia with an endotracheal tube is necessary. Attempting to avoid tracheal intubation, for example by using a mask, may lead to other complications, such as aspiration of stomach contents into the lungs. Some anaesthetists try to prevent dental damage by removing the oral airway before their patients regain consciousness and replacing it with a soft short tube placed in one nostril. (This is known as a nasal airway.)

Should any of your teeth be damaged or lost during an anaesthetic or operation, or while you are in the recovery room, you will need emergency treatment. This includes re-insertion of the tooth (if appropriate) and emergency dental consultation (if available). Great effort should be made to locate any missing teeth and you may need to have a chest X-ray to ensure that you have not inhaled the tooth. If you have and the tooth is not removed from your lung, then there is a high probability of pneumonia.

Similarly, children may undergo anaesthesia when their first teeth are about to be lost. These first teeth are very easily dislodged, and you should tell the anaesthetist which teeth are loose. Sometimes parents request the anaesthetist remove a tooth that is about to fall out!

Adults with loose teeth should see a dentist, if possible, before their anaesthetic. The same suggestion applies if any of the teeth are badly broken or decayed. In addition, professional dental cleaning is recommended for patients who have gum disease, especially for those patients who are scheduled to have a major operation.

Bruises

Patients often develop a small bruise at the site of insertion of the intravenous cannula, in the back of the hand, in the forearm near the wrist, or in the bend of the elbow. These bruises can become painful and may take a week or so to resolve. Elderly patients, and those with fragile skin and veins, bruise more easily and the bruise often takes longer to disappear.

Eye problems

Various types of eye damage may occur. The cornea or surface of the eye may be scratched when the eyelids are not completely closed, particularly if the face is covered with drapes or towels. Some anaesthetists choose to secure the eyelids closed with tape – although certain patients may develop skin reactions and others may complain of loss of eyelashes after removal of the tape. Other anaesthetists choose to insert a lubricating ointment into the eye – although eye infections have been reported if the ointment is contaminated. Some patients have complained of blurring of vision for a few hours postoperatively, because of the residual ointment. However, corneal damage may occur even if the eye is lubricated and taped shut. The presence of make-up, such as mascara, is potentially hazardous.

Blindness after both general and regional anaesthesia is rare, but it can occur. Loss of vision may result from pressure on the eye. It may be that the arteries at the back of the eye (retina) become compressed, thus depriving the eye of oxygen. Smokers are more at risk than are nonsmokers, because nicotine constricts or narrows arteries, further depriving the eye and the brain of oxygen. Temporary blindness may also occur after spinal anaesthesia for resection of the prostate gland in men. This is due to the effect of a special chemical in the fluid placed in the bladder by the surgeon during the course of the operation.

Nerve damage

Almost any nerve can be damaged. Nerves of the face may be damaged by pressure from the anaesthetic breathing circuit or from the anaesthetist’s fingers holding the facemask on and the chin forward. The most common nerve injury is to the ulnar nerve at the elbow, from compression against a hard surface. In general, the prevention of nerve damage is by careful positioning and padding of the patient during anaesthesia. In the past, the cause of postoperative nerve damage was always thought due to improper positioning of the patient; however, some patients who develop nerve damage have been found to have a pre-existing problem.

Nosebleed

Sometimes, instead of passing the breathing (endotracheal) tube through your mouth, your anaesthetist chooses to pass it into one nostril and down the back of the throat and into your voice box ( larynx). This change in route may still involve insertion of the laryngoscope into your mouth, so that your anaesthetist can see where he or she is placing the tube. Nasal intubation is normally used for operations around the face and mouth.

Insertion of the tube through the nostril often results in some bleeding from the nose after the tube is removed. This bleeding normally stops after a few minutes, although seeing the nose bleed may be distressing to family members.

Blood clots

Certain patients are at increased risk of having blood clots – for example, those taking oral contraceptives or hormone replacement. Certain surgical procedures also increase the risk of clots, such as operations that last several hours or are on the lower part of the body. In general, anaesthetics do not increase the risk of having a blood clot.

Brain damage

Some operations may lead to a decrease in intellectual ability, for example, after major brain or open heart surgery. Other patients are at risk because of pre-existing medical conditions, such as age-related loss of memory. Elderly patients, particularly those with progressive heart disease, high blood pressure or a history of minor strokes may suffer permanent changes after anaesthesia. This may be a result of a change in critical blood supply to certain parts of the brain, altering specific chemicals in the brain.

Blood supply to the brain may be subtly altered by a decrease in the amount of carbon dioxide in the blood and by slight changes in blood pressure. Many anaesthetic drugs have side effects which can alter blood flow, although modern drugs are less likely to produce these effects.

On rare occasions, patients have suffered brain damage due to lack of oxygen delivery to the brain. Even though all aspects of the anaesthetic are carefully monitored during an anaesthetic, sometimes problems can occur.

References
  1. Anesthesia. Medline Plus. https://medlineplus.gov/anesthesia.html
  2. Anesthesia. https://www.nigms.nih.gov/Education/pages/factsheet_Anesthesia.aspx
  3. Becker DE, Reed KL. Essentials of local anesthetic pharmacology. Anesth Prog. 2006;53(3):98–108.
  4. Salam GA. Regional anesthesia for office procedures: part I. Head and neck surgeries. Am Fam Physician. 2004;69(3):585–590.
  5. Liu W, Yang X, Li C, Mo A. Adverse drug reactions to local anesthetics: a systematic review. Oral Surg Oral Med Oral Pathol Oral Radiol. 2013;115(3):319–327.
  6. Berkun Y, Ben-Zvi A, Levy Y, Galili D, Shalit M. Evaluation of adverse reactions to local anesthetics: experience with 236 patients. Ann Allergy Asthma Immunol. 2003;91(4):342–345.
  7. González-Delgado P, Antón R, Soriano V, Zapater P, Niveiro E. Cross-reactivity among amide-type local anesthetics in a case of allergy to mepivacaine. J Investig Allergol Clin Immunol. 2006;16(5):311–313.
  8. Roberts JR, Hedges JR, eds. Clinical Procedures in Emergency Medicine. 5th ed. Philadelphia, Pa.: Saunders/ Elsevier; 2010:490–493.
  9. Sinnott CJ, Cogswell LP III, Johnson A, Strichartz GR. On the mechanism by which epinephrine potentiates lidocaine’s peripheral nerve block. Anesthesiology. 2003;98(1):181–188.
  10. Lalonde DH, Lalonde JF. Discussion. Do not use epinephrine in digital blocks: myth or truth? Part II. A retrospective review of 1111 cases. Plast Reconstr Surg. 2010;126(6):2035–2036.
  11. Muck AE, Bebarta VS, Borys DJ, Morgan DL. Six years of epinephrine digital injections: absence of significant local or systemic effects. Ann Emerg Med. 2010;56(3):270–274.
  12. Nath S, Häggmark S, Johansson G, Reiz S. Differential depressant and electrophysiologic cardiotoxicity of local anesthetics: an experimental study with special reference to lidocaine and bupivacaine. Anesth Analg. 1986;65(12):1263–1270.
  13. Santos AC, Pedersen H, Harmon TW, et al. Does pregnancy alter the systemic toxicity of local anesthetics? Anesthesiology. 1989;70(6):991–995.
  14. Infiltrative Anesthesia in Office Practice. Am Fam Physician. 2014 Jun 15;89(12):956-962. http://www.aafp.org/afp/2014/0615/p956.html
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DrugsDrugs & Supplements

Aspirin

Aspirin

What is aspirin

Aspirin also known as acetylsalicylic acid is one of the most widely used medical treatments worldwide. Following the advent of synthetic salicylate, Felix Hoffman, working at the Bayer company in Germany, made the acetylated form of salicylic acid in 1897 1. This drug was named “Aspirin” and it was not until 1971 when Vane discovered the mechanism by which aspirin exerts its anti-inflammatory, analgesic and antipyretic actions. He proved that aspirin and other non-steroid anti-inflammatory drugs (NSAIDs) inhibit the activity of the enzyme now called cyclooxygenase (COX) which leads to the formation of prostaglandins (PGs) that cause inflammation, swelling, pain and fever. However, by inhibiting this key enzyme in prostaglandin (PG) synthesis, the aspirin-like drugs also prevented the production of physiologically important prostaglandins (PGs) which protect the stomach mucosa from damage by hydrochloric acid, maintain kidney function and aggregate platelets when required.

Since then clinical trials involving tens of thousands of patients have since demonstrated that aspirin is effective for the prevention and treatment of heart attack and stroke 2. In patients who are at high risk because they already have occlusive vascular disease, long-term antiplatelet therapy (eg, with aspirin) reduces the yearly risk of serious vascular events (non-fatal myocardial infarction, non-fatal stroke, or vascular death) by about a quarter 3, 4. This decrease typically corresponds to an absolute reduction of about 10–20 per 1000 in the yearly incidence of non-fatal events, and to a smaller, but still definite, reduction in vascular death.

Aspirin and Prevention of Heart Attack

Most heart attacks and strokes occur when the blood supply to a part of your heart muscle or brain is blocked. This usually starts with atherosclerosis, a process in which deposits of fatty substances, cholesterol, cellular waste products, calcium and other substances build up in the inner lining of an artery. This buildup is called plaque.

Plaque usually affects large and medium-sized arteries. Plaques can grow large enough to significantly reduce the blood’s flow through an artery. But most of the damage occurs when a plaque becomes fragile and ruptures. Plaques that rupture cause blood clots to form that can block blood flow or break off and travel to another part of the body. This is called an embolism.

  • If a blood clot blocks a blood vessel that feeds the heart, it causes a heart attack.
  • If a blood clot blocks a blood vessel that feeds the brain, it causes a stroke.

Aspirin helps prevent blood clots from forming and helps prevent heart attack and stroke.

Certain patients will be prescribed aspirin combined with another antiplatelet drug (such as clopidogrel, prasugrel or ticagrelor) – also known as dual antiplatelet therapy (DAPT).

  • However, taking aspirin isn’t advised during a stroke, because not all strokes are caused by blood clots. Most strokes are caused by clots, but some are caused by ruptured blood vessels. Taking aspirin could potentially make these bleeding strokes more severe.

How Does Aspirin Work ?

Aspirin is a noncompetitive and irreversible irrecyclooxygenase-1 (COX-1) inhibitor 5 that prevents platelet aggregation and reduces the risk of heart attacks and strokes by preventing blood clots (due to aspirin’s anti-platelets effect, which works by preventing blood platelets from sticking together) from forming on the surface of ruptured atherosclerotic plaques. Atherosclerotic plaques build up along the lining of blood vessels over many years in response to injury caused by high blood pressure, abnormal blood sugar levels, high blood cholesterol levels, and toxins contained in tobacco smoke. Platelets stick to ruptured atherosclerotic plaques to form blood clots that block blood flow and thereby reduce oxygen delivery to tissues. Clots that block blood flow to heart muscle cause heart attacks, and clots that block blood flow to the brain cause strokes.

Noncoated aspirin acts within minutes of ingestion to stop platelets from forming blood clots. Enteric-coated aspirin takes longer to work but acts just as quickly as uncoated aspirin if chewed. Aspirin reduces the severity of heart attacks and strokes and prevents future heart attacks and strokes. The platelet-inhibitory effects of aspirin last for the life of the platelet (5 to 10 days), but patients need to take aspirin every day to inhibit new platelets that are constantly being released into the circulation.

What does anti-platelet mean ?

Blood platelets are actually fragments of cells – meaning they don’t contain all the necessary cellular equipment. When a person gets a cut or scratch, platelets release thromboxane, a chemical that signals other platelets to “help out.” Without the release of thromboxane, the platelets won’t come (stick) together, no clot will form, and the cut will continue to bleed. If you have a wound, thromboxane is an indispensable self-sealing material; but if you’re a stroke survivor, thromboxane’s ability to round up “help” to form a blood clot becomes potentially life-threatening.

Antiplatelet agents, including aspirin, clopidogrel, dipyridamole and ticlopidine, work by inhibiting the production of thromboxane. Aspirin is highly recommended for preventing a first stroke, but it and other antiplatelets also have an important role in preventing recurrent strokes.

According to a statement by the American Heart Association, taking aspirin within two days of an ischemic stroke reduces the severity of the stroke. In some cases, it prevents death. For long-term (meaning for the rest of your life unless otherwise specified by your physician) prevention, antiplatelet therapy is recommended primarily for people who have had a transient ischemic attack (TIA or “mini” stroke) or acute ischemic stroke.

Despite the potential benefits, antiplatelet therapy is not for everyone. People with a history of liver or kidney disease, gastrointestinal disease or peptic ulcers, high blood pressure, bleeding disorders or asthma may not be able to take aspirin or may require special dosage adjustments.

Is aspirin a blood thinner

No. Aspirin is an anti-platelet that keeps blood clots from forming by inhibiting the production of thromboxane, which prevents blood platelets from sticking together.

Blood thinners are also called anticoagulants. Anticoagulants target blood clotting factors, which are other agents that are crucial to the blood-clotting process. Clotting factors are proteins made in the liver. These proteins can’t be created in the liver without Vitamin K – a common vitamin found in cabbage, cauliflower, spinach and other leafy green vegetables. Anticoagulants, such as warfarin (Coumadin) and heparin, slow clot formation by competing with Vitamin K. This inhibits the circulation of certain clotting factors with the exotic names of factors II, VII, IX and X. Blood thinner decreases the clotting (coagulating) ability of the blood, although they do not actually thin the blood. They do NOT dissolve existing blood clots. Blood thinners are used to treat certain blood vessel, heart and lung conditions.

Blood thinners (anticoagulants) uses:

  • Helps to prevent harmful clots from forming in the blood vessels.
  • May prevent the clots from becoming larger and causing more serious problems.
  • Often prescribed to prevent first or recurrent stroke.

Commonly prescribed blood thinners (anticoagulants) include:

  • Rivaroxaban (Xarelto)
  • Dabigatran (Pradaxa)
  • Apixaban (Eliquis)
  • Heparin (various)
  • Warfarin (Coumadin)

Aspirin helps prevent clotting in patients who have had a heart attack, unstable angina, ischemic strokes, TIA (transient ischemic attacks, or “little strokes”) and other forms of cardiovascular disease. Usually prescribed preventively when atherosclerotic plaque buildup is evident but there is not yet a major obstruction in the artery. Certain patients will be prescribed aspirin combined with another antiplatelet drug – also known as dual antiplatelet therapy. For example, patients who have had heart attacks, patients who are treated with stents in their coronary arteries, and some patients who undergo coronary artery bypass graft surgery (CABG) are treated at the same time with two types of antiplatelet agents to prevent blood clotting. One antiplatelet agent is aspirin. Almost everyone with coronary artery disease, including those who have had a heart attack, stent, or CABG are treated with aspirin for the rest of their lives. A second type of antiplatelet agent, called a P2Y12 inhibitor [e.g. Clopidogrel (Plavix®), Dipyridamole, Prasugrel (Effient), Ticagrelor (Brilinta)], is usually prescribed for months or years in addition to the aspirin therapy. The type of medication and the duration of your treatment will vary based on a discussion with your healthcare provider weighing the risks of potential bleeding complications.

Is ibuprofen aspirin ?

Although ibuprofen is also a nonsteroidal anti-inflammatory drugs (NSAIDs) and have similar function (reduce pain, decrease fever or decrease inflammation) and side effects (increased risk of stomach ulcers) just like aspirin, but ibuprofen is NOT recommended for people with a heart attack, unstable angina,  ischemic strokes, TIA (transient ischemic attacks, or “little strokes”) and other forms of cardiovascular disease. The term nonsteroidal distinguishes these drugs from steroids, which, among a broad range of other effects, have a similar eicosanoid-depressing, anti-inflammatory action. First used in 1960, the term served to distance these medications from steroids 6.

People who take nonsteroidal anti-inflammatory drugs [common brands include Advil (ibuprofen); Motrin (ibuprofen); Aleve (naproxen)] (other than aspirin) such as ibuprofen may have a higher risk of having a heart attack or a stroke than people who do not take these medications. Studies estimate that a person’s relative risk of heart attack and stroke increases 10 percent to 50 percent when they regularly take an NSAID, depending on the particular drug and the dose being used, according to the Food and Drug Administration 7. Side effects affecting the kidneys, heart or the stomach also can occur when NSAIDs are taken at too high a dose, for too long, or in combination with another NSAID. Aspirin also is considered an NSAID but is not included in the warnings. Low-dose aspirin has been shown in clinical trials to reduce the risks of cardiovascular events in patients who have cardiovascular disease or who have already had a heart attack or stroke.

  • Do NOT take an NSAID such as ibuprofen if you have recently had a heart attack, unless directed to do so by your doctor.
  • Stop taking NSAIDs and seek medical help if you experience symptoms that might signal heart problems or stroke, such as chest pain, trouble breathing, sudden weakness in one part or side of the body, or sudden slurred speech 7.

Nonsteroidal anti-inflammatory drugs (NSAIDs) work to block enzymes called cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) that are responsible for manufacturing substances called postglandins (PGs), chemical messengers that can cause inflammation, pain and fever. These postglandins, however, also help regulate blood clotting, protect the lining of the stomach and intestine and help with kidney function 8. It is thought that inhibiting cyclooxygenase-2 (COX-2) leads to the anti-inflammatory, analgesic and antipyretic effects and that those NSAIDs also inhibiting COX-1 [COX-1 generated prostaglandins required to maintain physiological functions such as protection of the gastric mucosa, platelet aggregation], particularly aspirin, may cause gastrointestinal bleeding and ulcers in large doses 9.

Prescription ibuprofen is used to relieve pain, tenderness, swelling, and stiffness caused by osteoarthritis (arthritis caused by a breakdown of the lining of the joints) and rheumatoid arthritis (arthritis caused by swelling of the lining of the joints). It is also used to relieve mild to moderate pain, including menstrual pain (pain that happens before or during a menstrual period). Nonprescription ibuprofen is used to reduce fever and to relieve minor aches and pain from headaches, muscle aches, arthritis, menstrual periods, the common cold, toothaches, and backaches.

Is it safe to take aspirin during pregnancy ?

Generally, aspirin isn’t recommended during pregnancy unless you have certain medical conditions 10.

Low-dose aspirin — 60 to 100 milligrams daily — is sometimes recommended for pregnant women with recurrent pregnancy loss, clotting disorders and preeclampsia.

However, use of higher doses of aspirin poses various risks depending on the stage of pregnancy. During the first trimester, use of higher doses of aspirin poses a concern for pregnancy loss and congenital defects. Taking higher doses of aspirin during the third trimester increases the risk of the premature closure of a vessel in the fetus’s heart. Use of high-dose aspirin for long periods in pregnancy also increases the risk of bleeding in the brain of premature infants.

If you need to take aspirin during your third trimester of pregnancy, your health care provider will likely closely monitor you and your baby.

If you need to take a pain reliever during pregnancy, talk to your health care provider about the options. He or she might suggest occasional use of acetaminophen (Tylenol, others) instead of aspirin.

What Is the Dose of Aspirin ?

If rapid and complete platelet inhibition is required (eg, if a person is having a heart attack), the first dose of aspirin should be 160 to 325 mg 11. If noncoated aspirin is unavailable, enteric-coated tablets can be used but should be chewed to achieve a rapid effect.

For long-term prevention of cardiovascular disease, the recommended dose of aspirin is 75 to 325 mg once daily 11. Some guidelines recommend only baby aspirin (75 to 100 mg) for long-term prevention, based on evidence that higher doses cause more gastrointestinal bleeding but do not provide additional protection against heart attack and stroke 12.

What Are the Side Effects of Aspirin ?

Aspirin’s most common side effect is upper abdominal pain resulting from gastric irritation. This side effect might be avoided by taking aspirin with food. Enteric-coated aspirin is popular but is more expensive than noncoated aspirin and has not been shown to reduce symptoms of gastric irritation 13.

Aspirin causes gastrointestinal bleeding (an excess of up to 1 event for every 1000 patients treated for 1 year) 14. Risk of gastric irritation and bleeding can be reduced by the use of a proton pump inhibitor (eg, omeprazole) in combination with aspirin.

One to two percent of patients have an allergy to aspirin that can result in asthma or rarely, life-threatening allergy (anaphylaxis). Allergic patients can undergo a desensitization procedure. After undergoing desensitization, patients should not miss any doses of aspirin because this may lead to recurrence of the allergy.

Liver Toxicity

Liver injury from high doses of aspirin is usually mild and self-limited 15. Symptoms attributable to liver injury (as opposed to the other side effects of aspirin itself) are common but generally nonspecific and mild. Typically, alanine transaminase (ALT) elevations fall to normal within days of stopping. No convincing cases of acute liver failure or chronic liver injury or chronic vanishing bile duct syndrome due to aspirin have been published. Reye syndrome induced by aspirin, on the other hand, is a serious and potentially life threatening condition that should be managed with emergency intensive care.

Reye Syndrome

A special form of aspirin hepatotoxicity is Reye Syndrome, the development of lactic acidosis, microvesicular fat and hepatic dysfunction with encephalopathy and coma. Serum aminotransferase levels are usually markedly increased while serum bilirubin is minimally or only moderated elevated despite signs of hepatic failure such as hyperammonemia and encephalopathy. Reye syndrome usually occurs in children or young adults developing a few days to a week after a prodromal febrile illness, typically influenza B or varicella. It is often rapidly fatal, but in milder cases recovery is rapid. Reye syndrome was first reported in Australia in 1963, but subsequently was reported from around the world with increasing frequency and peaking in incidence in the 1970s and 1980s. Subsequently, case reports followed by careful epidemiological surveys linked the occurrence of Reye syndrome to receipt of aspirin during the prodromal viral illness. With medical recognition of this association, followed by wide scale public warnings, the use of aspirin in children with fever decreased markedly and the frequency of Reye syndrome fell dramatically. In the United States, reported cases of Reye syndrome fell from more than 500 cases per year before 1986 to less 2 cases per year thereafter. Occasional rare case reports of Reye syndrome still appear. Reye syndrome can also occur in adults.

The mitochondrial failure of Reye syndrome is rapidly reversible and the major focus of management should be clinical support during the acute phase. Infusions of 20% glucose may help sustain hepatic and brain function during the temporary mitochondrial failure. Recurrence of Reye syndrome has been reported in children who have recovered and were then treated again with aspirin during an acute febrile illness. Children who require long term therapy with aspirin or other mitochondrial inhibitors should receive influenza and varicella vaccine and parents should be alert to the signs and symptoms of Reye syndrome.

Aspirin intolerance

The National Institute for Clinical Excellence in the UK have defined aspirin intolerance as either a proven hypersensitivity to aspirin or a history of severe indigestion caused by low-dose aspirin 16. The prevalence of aspirin intolerance is between 6% and 20% with ‘true’ aspirin hypersensitivity occurring in 0.6–2.4% of the general population 17. Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) are contraindicated in patients with a history of hypersensitivity including asthma, angioedema, urticaria, or rhinitis. However, in patients with a definitive need for aspirin, desensitization may offer a viable option for delivery of treatment.

Aspirin hypersensitivity

Hypersensitivity reactions to aspirin have either a pharmacological or immunological basis, although patients may present with mixed reactions. Pharmacological reactions are dependent on inhibition of the cyclooxygenase-1 (COX-1) pathway while immunological/allergic reactions are mediated by drug-specific immunoglobulin E (IgE) production against aspirin 18. This is the basis for the difference between an anaphylactoid and anaphylactic reaction. Anaphylactic reactions are IgE mediated whereas anaphylactoid reactions can resemble anaphylactic symptoms but are not IgE mediated. Furthermore, aspirin may induce a pharmacological reaction at one time but an immunological reaction at another time in the same patient 19.

There are three basic clinical types of hypersensitivity reaction to aspirin: respiratory, cutaneous and systemic 20. While systemic reactions can be the most serious, respiratory and cutaneous reactions comprising urticaria and or angioedema are the most common.

Type 1: Aspirin-exacerbated respiratory disease

Aspirin-exacerbated respiratory disease (AERD) consists of asthma and rhinitis/nasal polyps. Aspirin-exacerbated respiratory disease is also commonly referred to as aspirin-sensitive, aspirin-induced or aspirin-intolerant asthma. The prevalence of aspirin-intolerant asthma is uncertain, but it has been estimated to affect about 1–20% of people with asthma 21. Respiratory reactions to aspirin begin within minutes to hours after ingestion. Classic symptoms of asthma are often accompanied by rhinitis, conjunctival irritation and facial flushing. In addition, abdominal cramping may occur 22. Aspirin-exacerbated respiratory disease most commonly occurs in patients between 30 and 40 years old, often after respiratory tract infection and is more common in women but is very uncommon in children 23. Most patients with aspirin-exacerbated respiratory disease can successfully undergo aspirin desensitization therapy.

Type 2: Cutaneous reactions

Aspirin-induced cutaneous disease consists of urticaria and angioedema. Cutaneous and systemic reactions to aspirin are less well characterized than aspirin-exacerbated respiratory disease. Urticaria occurs either separately or simultaneously with angioedema. Patients with chronic idiopathic urticaria are more sensitive to aspirin, urticaria being aggravated in 21–30% 24. When urticaria is active, patients are more likely to react to aspirin than if quiescent. Leukotriene-receptor antagonists can block NSAID-induced urticaria and angioedema reactions. Mixed reactions consisting of a combination of respiratory and cutaneous symptoms may also occur. Patients with chronic idiopathic urticaria are not thought to be suitable for aspirin desensitization 25.

Type 3: Systemic reactions

Systemic reactions occur within minutes of ingesting aspirin and consist of hypotension, swelling, laryngeal oedema, generalized pruritis, tachypnoea and lapses in consciousness. Angioedema with hypotension is generally considered a ‘systemic’ rather than a cutaneous reaction to aspirin. Some authors report successful desensitization where systemic reactions have occurred 19 while others do not 25. Because systemic reactions are potentially fatal, many authors recommend avoiding desensitization in these patients 26. It should be noted that terminology regarding the type of hypersensitivity reactions is inconsistent in the published literature and standardization in this area is essential if aspirin desensitization is to be implemented safely.

Who Should Take Aspirin ?

Guideline recommendations for aspirin use are summarized in the Table 1. Aspirin is recommended in patients with angina, previous heart attack or stroke (ie, secondary prevention), but it is not clear whether patients who have not previously experienced angina, heart attack or stroke benefit from aspirin (ie, primary prevention).

Table 1. Common Conditions in Which Aspirin Is Proven to Be of Benefit for the Prevention of Major Cardiovascular Events (Heart Attack, Stroke, Death) or Venous Thromboembolism (Blood Clots in the Legs or Lungs) or Is of Uncertain Benefit

Aspirin of Proven BenefitAspirin of Uncertain Benefit
Angina/heart attackPeripheral artery disease*
Coronary artery stents
StrokeDiabetes (no previous heart attack or stroke)*
Following coronary artery bypass graft surgeryPrimary prevention (ie, no angina, previous heart attack or stroke)
Prevention of blood clots in patients undergoing surgery for hip fracturePrevention of recurrent deep vein thrombosis and pulmonary embolism in patients who have completed treatment with warfarin

Note: The American College of Cardiology/American Heart Association Guidelines recommend aspirin for patients with peripheral artery disease and diabetes despite lack of conclusive evidence that it is beneficial.

[Source 13]

Conditions Where Aspirin Is Proven to Be Effective or Routinely Recommended

Coronary Artery Disease (Have Experienced Angina or a Heart Attack, or Have Undergone an Angioplasty With or Without Stent Placement)

Aspirin reduces the risk of major cardiovascular events (heart attack, stroke, cardiovascular death) by ≈25% (36 fewer events for every 1000 patients treated for 2 years) in patients with a recent heart attack 27. The American College of Cardiology/American Heart Association guidelines recommend aspirin at a dose of 75 to 325 mg once daily for patients with a history of heart attack 12. Patients with a recent heart attack and those who have undergone angioplasty and stenting are usually prescribed a second antiplatelet drug, clopidogrel, prasugrel, or ticagrelor, in combination with baby aspirin. The combination of 2 antiplatelet drugs further increases the risk of major bleeding (10 additional events for every 1000 patients treated for 1 year) in comparison with aspirin alone 12.

Cerebral Vascular Disease (Have Experienced a Stroke or Transient Ischemic Attack [Ministroke])

Aspirin reduces the risk of major cardiovascular events by ≈22% (36 fewer events for every 1000 patients treated for 2 years) in patients with a recent stroke 14. The American Heart Association/American Stroke Association guidelines recommend aspirin at a dose of 50 to 325 mg once daily for patients with a history of stroke 28. Not all stroke patients should take aspirin; ≈1 in 6 strokes is caused by blood clots that arise in the heart; in such patients, the anticoagulants warfarin, dabigatran, and rivaroxaban are more effective than aspirin and are generally preferred. Aspirin is not known to benefit patients with stroke caused by bleeding into the brain.

Have Undergone Coronary Artery Bypass Graft Surgery

Aspirin reduces the risk of coronary artery bypass graft failure by ≈30% in patients who have recently undergone coronary artery bypass graft surgery. By preventing graft failure, it is logical to expect that aspirin will also prevent heart attacks resulting from a blocked graft, but this is unproven. The American College of Cardiology/American Heart Association guidelines recommend aspirin at a dose of 75 to 162 mg once daily for patients who have undergone coronary artery bypass graft surgery 29.

Have Undergone Surgery for Fractured Hip to Prevent Blood Clots in the Legs or Lungs

The pulmonary embolism prevention study has shown in patients undergoing surgery for hip fracture that aspirin given at a dose of 160 mg once daily reduces the risk of developing blood clots in the legs (deep vein thrombosis) or lungs (pulmonary embolism) by ≈30% (9 fewer events for every 1000 patients treated for 35 days) 30. Many physicians prefer to use other treatments (eg, heparin, enoxaparin, fondaparinux, rivaroxaban) over aspirin for prevention of deep vein thrombosis and pulmonary embolism in patients undergoing hip fracture surgery.
Conditions Where a Benefit of Aspirin Is Uncertain or Unknown

Have Never Experienced a Heart Attack or Stroke But are >50 Years of Age (ie, Primary Prevention)

Primary prevention trials involving a combined total of 100 000 patients have shown that aspirin reduces the risk of a first heart attack by ≈20% (1 fewer event for every 1000 patients treated for 1 year) 31. In low-risk patients, the benefit of aspirin may be outweighed by the increase in bleeding (up to 1 more event per 1000 patients treated for 1 year). Calculators are available (http://www.mdcalc.com/framingham-cardiac-risk-score) to estimate the risk of major cardiovascular events in the next 10 years in patients who have not previously experienced a heart attack or stroke. If the risk exceeds 10% over 10 years, aspirin is likely to be associated with a net benefit. The American Heart Association guidelines recommend aspirin at a dose of 75 to 160 mg once daily if used for primary prevention 32.

Diagnosed With Peripheral Artery Disease (Have Experienced Claudication [Leg Pain While Walking] or Rest Pain That Is Caused by Blockages in the Leg Blood Vessels)

Despite having an increased risk of heart attack and stroke, patients with peripheral artery disease have not been shown to benefit from aspirin. Nevertheless, most guidelines recommend aspirin for patients with peripheral artery disease. The dose of aspirin recommended by the American College of Cardiology/American Heart Association guidelines for patients with peripheral artery disease is 75 to 325 mg once daily 33.

Diabetes Mellitus But Have Never Experienced a Heart Attack or Stroke

The risk of heart attack in patients with diabetes mellitus who have never experienced a heart attack is similar to the risk of a recurrent heart attack in patients without diabetes mellitus who have already had a heart attack. Primary prevention trials have not shown a benefit of aspirin in patients with diabetes mellitus, but most guidelines recommend that adult patients with diabetes mellitus should be treated with aspirin. The dose recommended by the American Diabetes Association/American Heart Association/American College of Cardiology Foundation guidelines is 75 to 162 mg daily 34.

Have Had a Blood Clot in the Leg or Lungs

There is currently no evidence that aspirin is effective for prevention of recurrent deep vein thrombosis or pulmonary embolism, but studies are ongoing to address this issue.

Currently Taking Warfarin

The combination of aspirin and warfarin is more effective than warfarin alone in patients who have a mechanical heart valve and is more effective than aspirin alone in patients with a recent heart attack, but will increase the risk of bleeding 35. Triple therapy, with the combination of aspirin, clopidogrel, and warfarin may be of benefit in patients with a recent heart attack or coronary stent who also have atrial fibrillation 36. To minimize the risk of bleeding when aspirin is combined with warfarin, the dose of aspirin should not exceed 100 mg once daily.

Should You Stop Aspirin Before Undergoing Surgery ?

Aspirin increases the risk of bleeding if it is continued during surgery, but it is not known whether continuing aspirin will also protect against the risk of heart attack or stroke. Studies are presently ongoing to address this issue. Current guidelines recommend that aspirin should be stopped 7 to 10 days before surgery to avoid an increase in risk of bleeding 37. The exception is patients with coronary stents, who should always check with their clinicians before stopping either aspirin or any of the other antiplatelet agents—clopidogrel, prasugrel, or ticagrelor—used to prevent stent thrombosis.

Aspirin uses

The current interest in aspirin stems from the fact that many animal experiments and human epidemiological studies now link aspirin (and other non-steroidal anti-inflammatory drugs) with beneficial effects in various cancers, including breast, ovarian, oesophageal, and colorectal cancer 38. Recent meta-analyses supported the idea that the overall relative risk of colorectal cancer is reduced in people taking long term aspirin 39. Another meta-analysis of observational data confirmed a protective effect in oesophageal cancer and provided evidence of a relation with dose and duration of treatment, and other studies showed a beneficial effect in ovarian cancer 40. How aspirin or other non-steroidal anti-inflammatory drugs produce this effect is not entirely clear, but the synthesis or activity of COX 2 is increased in many tumours, and inhibition could activate apoptotic mechanisms or suppress angiogenesis 41. It has even been suggested that the link between diet and the prevention of colorectal cancer is attributable to the presence of salicylic acid in plant and vegetable foodstuffs 42.

Evidence from longitudinal studies of long term users of non-steroidal anti-inflammatory drugs originally pointed to a reduced risk of Alzheimer’s disease 43 and these findings are supported by other, more recent data 44, where an inverse relation was found between taking aspirin (and other non-steroidal anti-inflammatory drugs) and Alzheimer’s disease, but not other forms of dementia. The mechanism is uncertain—Alzheimer’s has an inflammatory component and therefore COX 2 may be the target, although other mechanisms have been suggested 45.

The US Preventive Services Task Force 46 recommends initiating low-dose aspirin use for the primary prevention of cardiovascular disease and colorectal cancer in adults aged 50 to 59 years who have a 10% or greater 10-year cardiovascular disease risk, are not at increased risk for bleeding, have a life expectancy of at least 10 years, and are willing to take low-dose aspirin daily for at least 10 years

Table 1. US Preventive Services Task Force Recommendation Summary

PopulationRecommendationGrade
Adults aged 50 to 59 years with a ≥10% 10-year CVD riskThe USPSTF recommends initiating low-dose aspirin use for the primary prevention of cardiovascular disease (CVD) and colorectal cancer (CRC) in adults aged 50 to 59 years who have a 10% or greater 10-year CVD risk, are not at increased risk for bleeding, have a life expectancy of at least 10 years, and are willing to take low-dose aspirin daily for at least 10 years.B
Adults aged 60 to 69 years with a ≥10% 10-year CVD riskThe decision to initiate low-dose aspirin use for the primary prevention of CVD and CRC in adults aged 60 to 69 years who have a 10% or greater 10-year CVD risk should be an individual one. Persons who are not at increased risk for bleeding, have a life expectancy of at least 10 years, and are willing to take low-dose aspirin daily for at least 10 years are more likely to benefit. Persons who place a higher value on the potential benefits than the potential harms may choose to initiate low-dose aspirin.C
Adults younger than 50 yearsThe current evidence is insufficient to assess the balance of benefits and harms of initiating aspirin use for the primary prevention of CVD and CRC in adults younger than 50 years.I
Adults aged 70 years or olderThe current evidence is insufficient to assess the balance of benefits and harms of initiating aspirin use for the primary prevention of CVD and CRC in adults aged 70 years or older.I

Note:

Grade B: The USPSTF recommends the service. There is high certainty that the net benefit is moderate or there is moderate certainty that the net benefit is moderate to substantial.

Grade C: The USPSTF recommends selectively offering or providing this service to individual patients based on professional judgment and patient preferences. There is at least moderate certainty that the net benefit is small.

Grade I: The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of the service. Evidence is lacking, of poor quality, or conflicting, and the balance of benefits and harms cannot be determined.

[Source 46]

However, questions remain about safety, side effects and dosage of aspirin for its an exciting therapeutic prospects. For example, what is the minimum dose required to achieve these effects and how can scientists and doctors assess the relative risk and benefit of a preventive treatment that will entail treating healthy people for many years with a drug known to have gastric and other side effects ? To better answer questions about safety and who is most likely to benefit from aspirin, researchers are awaiting the results of several ongoing clinical trials that are testing aspirin.

Aspirin overdose

Aspirin overdose remains a significant public health threat with more than 20,000 exposures reported annually in the United States 47. In adult Emergency Department patients with acute aspirin poisoning, independent predictors of severe outcome were older age and increased respiratory rate, as well as initial serum lactate. Mortality increases with the measured serum salicylate level.

The variation of presenting symptoms of aspirin overdose contributes to inconsistent treatments in the emergency department. Patients with severe aspirin overdose require a high minute ventilation. Early in the course of an overdose, a patient will require hyperventilation. If they become too fatigued to compensate, mechanical ventilation may be needed. It can be impossible to recreate such a high minute ventilation with mechanical ventilation. This places patients at a high risk for decompensation and death. Hemodialysis is an effective elimination technique for salicylate overdose and should be considered early. In a review 48 of aspirin overdose that were reported to the Illinois Poison Center from 2003–2014, it was found that timely hemodialysis for intubated salicylate overdose patients decreases mortality.

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  36. Faxon DP, Eikelboom JW, Berger PB, Holmes DR Jr., Bhatt DL, Moliterno DJ, Becker RC, Angiolillo DJ. Antithrombotic therapy in patients with atrial fibrillation undergoing coronary stenting: a North American perspective: executive summary. Circ Cardiovasc Interv. 2011;4:522–534. http://circinterventions.ahajournals.org/content/4/5/522
  37. AHA/ACC, National Heart, Lung, and Blood Institute. AHA/ACC guidelines for secondary prevention for patients with coronary and other atherosclerotic vascular disease: 2006 update: endorsed by the National Heart, Lung, and Blood Institute. Circulation. 2006;113: 2363–2372. http://circ.ahajournals.org/content/113/19/2363
  38. Aspirin and colorectal cancer: the promise of precision chemoprevention. Nature Reviews Cancer 16, 173–186 (2016). doi:10.1038/nrc.2016.4. https://www.nature.com/articles/nrc.2016.4
  39. Bosetti C, Gallus S, La Vecchia C. Aspirin and cancer risk: an update to 2001. Eur J Cancer Prev 2002;11: 535-42. https://www.ncbi.nlm.nih.gov/pubmed/12457105
  40. Corley DA, Kerlikowske K, Verma R, Buffler P. Protective association of aspirin/NSAIDs and esophageal cancer: a systematic review and meta-analysis. Gastroenterology 2003;124: 47-56. https://www.ncbi.nlm.nih.gov/pubmed/12512029
  41. Thun MJ, Henley SJ, Patrono C. Nonsteroidal anti-inflammatory drugs as anticancer agents: mechanistic, pharmacologic, and clinical issues. J Natl Cancer Inst 2002;94: 252-66. https://www.ncbi.nlm.nih.gov/pubmed/11854387
  42. Paterson JR, Lawrence JR. Salicylic acid: a link between aspirin, diet and the prevention of colorectal cancer. QJM 2001;94: 445-8. https://www.ncbi.nlm.nih.gov/pubmed/11493722
  43. Stewart WF, Kawas C, Corrada M, Metter EJ. Risk of Alzheimer’s disease and duration of NSAID use. Neurology 1997;48: 626-32. https://www.ncbi.nlm.nih.gov/pubmed/9065537
  44. Broe GA, Grayson DA, Creasey HM, Waite LM, Casey BJ, Bennett HP, et al. Anti-inflammatory drugs protect against Alzheimer disease at low doses. Arch Neurol 2000;57: 1586-91. https://www.ncbi.nlm.nih.gov/pubmed/11074790
  45. Gao F, Bales KR, Dodel RC, Liu J, Chen X, Hample H, et al. NF-kappaB mediates IL-1beta-induced synthesis/release of alpha2-macroglobulin in a human glial cell line. Brain Res Mol Brain Res 2002;105: 108-14. https://www.ncbi.nlm.nih.gov/pubmed/12399113
  46. Aspirin Use to Prevent Cardiovascular Disease and Colorectal Cancer: Preventive Medication. US Preventive Services Task Force. https://www.uspreventiveservicestaskforce.org/Page/Document/UpdateSummaryFinal/aspirin-to-prevent-cardiovascular-disease-and-cancer
  47. Acute salicylate poisoning: risk factors for severe outcome. Rachel M. Shively, Robert S. Hoffman & Alex F. Manini. Clinical Toxicology Vol. 55 , Iss. 3,2017. http://www.tandfonline.com/doi/full/10.1080/15563650.2016.1271127
  48. The association of hemodialysis and survival in intubated salicylate-poisoned patients. The American Journal of Emergency Medicine , Volume 35 , Issue 6 , 899 – 903.
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DrugsDrugs & Supplements

Colloidal silver

Colloidal-Silver

What is colloidal silver

Colloidal silver consists of tiny silver particles in a liquid — the same type of precious metal used in jewelry, dental fillings, silverware, make photographs, in brazing alloys and other consumer goods 1. It’s sometimes promoted on the internet as a dietary supplement, but evidence supporting health-related claims is lacking.

Colloidal silver can be dangerous to your health. Silver has no known purpose in the body. Nor is it an essential mineral, as some sellers of silver products claim.

Silver is a naturally occurring element. It is found in the environment combined with other elements such as sulfide, chloride, and nitrate. Pure silver is “silver” colored, but silver nitrate and silver chloride are powdery white and silver sulfide and silver oxide are dark-gray to black. Silver is often found as a by-product during the retrieval of copper, lead, zinc, and gold ores.

People may be exposed to silver, usually in tiny amounts, through air, water, and food, and in certain activities such as jewelry-making or soldering.

Colloidal silver products are usually marketed as dietary supplements that are taken by mouth. Colloidal silver products also come in forms to be injected or applied to the skin. Manufacturers of colloidal silver products often claim that they are cure-alls, boosting your immune system, fighting bacteria and viruses, and treating cancer, HIV/AIDS, shingles, herpes, eye ailments and prostatitis.

However, no sound scientific studies to evaluate these health claims have been published in reputable medical journals. In fact, the Food and Drug Administration has taken action against some manufacturers of colloidal silver products for making unproven health claims 2, 3.

Topical silver (used on the skin) has some appropriate medical uses, such as in bandages and dressings to treat burns, skin wounds, or skin infections. It’s also in medicines to prevent conjunctivitis (an eye condition) in newborns. However, there are no legally marketed prescription or over-the-counter drugs containing colloidal silver that are taken by mouth.

Lastly, in 1999 the Food and Drug Administration (FDA)  warned that colloidal silver isn’t safe or effective for treating any disease or condition. The FDA also issued a final ruling establishing that all over-the-counter (OTC) drug products containing colloidal silver ingredients or silver salts for internal or external use are not generally recognized as safe and effective and are misbranded. FDA is issuing this final rule because many OTC drug products containing colloidal silver ingredients or silver salts are being marketed for numerous serious disease conditions and FDA is not aware of any substantial scientific evidence that supports the use of OTC colloidal silver ingredients or silver salts for these disease conditions. This regulation is effective September 16, 1999 4.

Colloidal silver side effects

Animal studies have shown that swallowing silver results in the deposit of silver in the skin. One study in mice found that the animals exposed to silver in drinking water were less active than unexposed animals.

No studies are available on whether silver affects reproduction or causes developmental problems in people.

It’s not clear how much colloidal silver may be harmful, but it can build up in your body’s tissues over months or years. Most commonly, this results in ARGYRIA, a blue-gray discoloration of your skin, eyes, internal organs, nails and gums. While argyria doesn’t usually pose a serious health problem, it can be a cosmetic concern because it doesn’t go away when you stop taking silver products.

Rarely, excessive doses of colloidal silver can cause possibly irreversible serious health problems, including kidney damage and neurological problems such as seizures.

Colloidal silver products may also interact with medications, including penicillamine (Cuprimine, Depen), quinolone antibiotics, tetracycline and thyroxine (Unithroid, Levoxyl, Synthroid) medications.

How likely is silver to cause cancer ?

No studies are available on whether silver may cause cancer in people 5, 6. The only available animal studies showed both positive and negative results when silver was implanted under the skin.

The Environment Protection Authority (EPA) has determined that silver is not classifiable as to human carcinogenicity.

The EPA recommends that the concentration of silver in drinking water not exceed 0.10 milligrams per liter of water (0.10 mg/L) because of the skin discoloration that may occur.

The EPA requires that spills or accidental releases of 1,000 pounds or more of silver be reported to the EPA.

The Occupational Safety and Health Administration (OSHA) limits silver in workplace air to 0.01 milligrams per cubic meter (0.01 mg/m3) for an 8-hour workday, 40-hour workweek. The National Institute of Occupational Safety and Health (NIOSH) also recommends that workplace air contain no more that 0.01 mg/m3 silver.

The American Conference of Governmental Industrial Hygienists (ACGIH) recommends that workplace air contain no more than 0.1 mg/m3 silver metal and 0.01 mg/m3 soluble silver compounds.

References
  1. Colloidal Silver. National Center for Complementary and Integrative Health. https://nccih.nih.gov/health/silver
  2. Inspections, Compliance, Enforcement, and Criminal Investigations. U.S. Food and Drug Administration. https://www.fda.gov/ICECI/EnforcementActions/WarningLetters/2013/ucm354221.htm
  3. FDA’s Electronic Reading Room – Warning Letters. https://www.accessdata.fda.gov/scripts/warningletters/wlSearchResult.cfm?qryStr=colloidal%20silver&webSearch=true
  4. Rulemaking History for OTC Colloidal Silver Drug Products. U.S. Food and Drug Administration. https://www.gpo.gov/fdsys/pkg/FR-1999-08-17/pdf/99-21253.pdf
  5. ToxFAQsTM for Silver. Agency for Toxic Substances and Disease Registry. https://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=538&tid=97
  6. SILVER, ELEMENTAL. Toxnet, U.S. Library of Medicine. https://toxnet.nlm.nih.gov/cgi-bin/sis/search/r?dbs+hsdb:@term+@rn+@rel+7440-22-4
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Digestive SystemDrugsDrugs & SupplementsSmall and Large Intestine

Small intestine cancer

small intestine cancer

Small intestine cancer

Small intestine cancer is a rare disease in which malignant (cancer) cells form in the tissues of the small intestine 1.

The small intestine (also called small bowel) is part of the body’s digestive system, which also includes the esophagus, stomach, and large intestine. The digestive system removes and processes nutrients (vitamins, minerals, carbohydrates, fats, proteins, and water) from foods and helps pass waste material out of the body.

The small intestine is a long tube that connects the stomach to the large intestine. It folds many times to fit inside the abdomen. The small intestine consists of three parts: the duodenum, the jejunum, and the ileum (Figure 1). The duodenum, about 25 centimeters long and 5 centimeters in diameter, lies posterior to the parietal peritoneum and is the most fixed portion of the small intestine. It follows a C-shaped path as it passes anterior to the right kidney and the upper three lumbar vertebrae. The remainder of the small intestine is mobile and lies free in the peritoneal cavity. The proximal two-fifths of this portion of the small intestine is the jejunum, and the remainder is the ileum. The jejunum and ileum are not easily distinguished as separate parts; however, the diameter of the jejunum is typically greater than that of the ileum, and its wall is thicker, more vascular, and more active.

A double-layered fold of peritoneal membrane called mesentery suspends the jejunum and ileum from the posterior abdominal wall (Figure 2). The mesentery supports the blood vessels, nerves, and lymphatic vessels that supply the intestinal wall. A filmy, double fold of peritoneal membrane called the greater omentum drapes like an apron from the stomach over the transverse colon and the folds of the small intestine.

Estimated new cases and deaths from small intestine cancer in the United States in 2017 2:

  • New cases: 10,190.
  • Deaths: 1,390.

There are five types of small intestine cancer. The types of cancer found in the small intestine are:

  1. Adenocarcinoma (majority of cases).
  2. Lymphoma (uncommon), which is usually of the non-Hodgkin type.
  3. Sarcoma (most commonly leiomyosarcoma and more rarely angiosarcoma or liposarcoma).
  4. Gastrointestinal stromal tumor.
  5. Carcinoid tumors.

Approximately 25% to 50% of the primary malignant tumors in the small intestine are adenocarcinomas, and most occur in the duodenum 3. Small intestine carcinomas may occur synchronously (existing at the same time) or metachronously (multiple separate occurrences at different intervals) at multiple sites 4.

Leiomyosarcoma starts in the smooth muscle cells of the small intestine. Most of these tumors occur in the part of the small intestine near the large intestine most often in the ileum 4.

Some 20% of malignant lesions of the small intestine are carcinoid tumors, which occur more frequently in the ileum than in the duodenum or jejunum and may be multiple 4.

It is uncommon to find malignant lymphoma as a solitary small intestine lesion 4.

Together they account for the majority of small intestine malignancies, which, as a whole, account for only 1% to 2% of all gastrointestinal malignancies 5, 6, 7, 8.

Diet and health history can affect the risk of developing small intestine cancer

Anything that increases your risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. Talk with your doctor if you think you may be at risk. Risk factors for small intestine cancer include the following:

  • Eating a high-fat diet.
  • Having Crohn disease.
  • Having celiac disease.
  • Having familial adenomatous polyposis.

Small intestine cancer survival rate

The prognosis (chance of recovery) and treatment options depend on the following:

  • The type of small intestine cancer.
  • Whether the cancer is in the inner lining of the small intestine only or has spread into or beyond the wall of the small intestine.
  • Whether the cancer has spread to other places in the body, such as the lymph nodes, liver, or peritoneum (tissue that lines the wall of the abdomen and covers most of the organs in the abdomen).
  • Whether the cancer can be completely removed by surgery.
  • Whether the cancer is newly diagnosed or has recurred.

As in other gastrointestinal malignancies, the predominant modality of treatment is surgery when resection is possible, and cure relates to the ability to completely resect the cancer. The overall 5-year survival rate for resectable adenocarcinoma is only 20%. The 5-year survival rate for resectable leiomyosarcoma, the most common primary sarcoma of the small intestine, is approximately 50% 1.

Figure 1.  Parts of the small intestine

small intestine cancer

Figure 2. Small intestines

symptoms of small intestine cancer

Stage Information for Small Intestine Cancer

Staging is used to find out how far the cancer has spread, but treatment decisions are not based on stage.

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

  1. Tissue. The cancer spreads from where it began by growing into nearby areas.
  2. Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
  3. Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

The American Joint Committee on Cancer has designated staging by TNM classification to define small intestine cancer 3.

Table 1. Primary Tumor (T)

TXPrimary tumor cannot be assessed.
T0No evidence of primary tumor.
TisCarcinoma in situ.
T1aTumor invades lamina propria.
T1bTumor invades submucosa. (a)
T2Tumor invades muscularis propria.
T3Tumor invades through the muscularis propria into the subserosa or into the nonperitonealized perimuscular tissue (mesentery or retroperitoneum) with extension ≤2 cm. (a)
T4Tumor perforates the visceral peritoneum or directly invades other organs or structures (includes other loops of small intestine, mesentery, or retroperitoneum >2 cm, and abdominal wall by way of serosa; for duodenum only, invasion of pancreas or bile duct).

(a): The nonperitonealized perimuscular tissue is, for jejunum and ileum, part of the mesentery and, for duodenum in areas where serosa is lacking, part of the interface with the pancreas.

[Source 3]

Table 2. Regional Lymph Nodes (N)

NXRegional lymph nodes cannot be assessed.
N0No regional lymph node metastasis.
N1Metastasis in 1–3 regional lymph nodes.
N2Metastases in ≥4 regional lymph nodes.
[Source 3]

Table 3. Distant Metastasis (M)

M0No distant metastasis.
M1Distant metastasis.
[Source 3]

Table 4. Anatomic Stage/Prognostic Groups

StageTNM
0TisN0M0
IT1N0M0
T2N0M0
IIAT3N0M0
IIBT4N0M0
IIIAAny TN1M0
IIIBAny TN2M0
IVAny TAny NM1
[Source 3]

Cancer may spread from where it began to other parts of the body.

When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.

  • Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
  • Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.

The metastatic tumor is the same type of cancer as the primary tumor. For example, if small intestine cancer spreads to the liver, the cancer cells in the liver are actually small intestine cancer cells. The disease is metastatic small intestine cancer, not liver cancer.

Small intestine cancer is grouped according to whether or not the tumor can be completely removed by surgery.

Treatment depends on whether the tumor can be removed by surgery and if the cancer is being treated as a primary tumor or is metastatic cancer.

  • Recurrent Small Intestine Cancer

Recurrent small intestine cancer is cancer that has recurred (come back) after it has been treated. The cancer may come back in the small intestine or in other parts of the body.

Small intestine cancer signs and symptoms

Signs and symptoms of small intestine cancer include unexplained weight loss and abdominal pain.

These and other signs and symptoms may be caused by small intestine cancer or by other conditions. Check with your doctor if you have any of the following:

  • Pain or cramps in the middle of the abdomen.
  • Weight loss with no known reason.
  • A lump in the abdomen.
  • Blood in the stool.

Tests that examine the small intestine are used to detect (find), diagnose, and stage small intestine cancer

Procedures that make pictures of the small intestine and the area around it help diagnose small intestine cancer and show how far the cancer has spread. The process used to find out if cancer cells have spread within and around the small intestine is called staging.

In order to plan treatment, it is important to know the type of small intestine cancer and whether the tumor can be removed by surgery. Tests and procedures to detect, diagnose, and stage small intestine cancer are usually done at the same time. The following tests and procedures may be used:

  • Physical exam and history : An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
  • Blood chemistry studies : A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease.
  • Liver function tests : A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by the liver. A higher than normal amount of a substance can be a sign of liver disease that may be caused by small intestine cancer.
  • Endoscopy : A procedure to look at organs and tissues inside the body to check for abnormal areas. There are different types of endoscopy:

Upper endoscopy : A procedure to look at the inside of the esophagus, stomach, and duodenum (first part of the small intestine, near the stomach). An endoscope is inserted through the mouth and into the esophagus, stomach, and duodenum. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue samples, which are checked under a microscope for signs of cancer.

Capsule endoscopy : A procedure to look at the inside of the small intestine. A capsule that is about the size of a large pill and contains a light and a tiny wireless camera is swallowed by the patient. The capsule travels through the digestive tract, including the small intestine, and sends many pictures of the inside of the digestive tract to a recorder that is worn around the waist or over the shoulder. The pictures are sent from the recorder to a computer and viewed by the doctor who checks for signs of cancer. The capsule passes out of the body during a bowel movement.

Double balloon endoscopy : A procedure to look at the inside of the small intestine. A special instrument made up of two tubes (one inside the other) is inserted through the mouth or rectum and into the small intestine. The inside tube (an endoscope with a light and lens for viewing) is moved through part of the small intestine and a balloon at the end of it is inflated to keep the endoscope in place. Next, the outer tube is moved through the small intestine to reach the end of the endoscope, and a balloon at the end of the outer tube is inflated to keep it in place. Then, the balloon at the end of the endoscope is deflated and the endoscope is moved through the next part of the small intestine. These steps are repeated many times as the tubes move through the small intestine. The doctor is able to see the inside of the small intestine through the endoscope and use a tool to remove samples of abnormal tissue. The tissue samples are checked under a microscope for signs of cancer. This procedure may be done if the results of a capsule endoscopy are abnormal. This procedure is also called double balloon enteroscopy.

  • Laparotomy : A surgical procedure in which an incision (cut) is made in the wall of the abdomen to check the inside of the abdomen for signs of disease. The size of the incision depends on the reason the laparotomy is being done. Sometimes organs or lymph nodes are removed or tissue samples are taken and checked under a microscope for signs of disease.
  • Biopsy : The removal of cells or tissues so they can be viewed under a microscope to check for signs of cancer. This may be done during an endoscopy or laparotomy. The sample is checked by a pathologist to see if it contains cancer cells.
  • Upper GI series with small bowel follow-through: A series of x-rays of the esophagus, stomach, and small bowel. The patient drinks a liquid that contains barium (a silver-white metallic compound). The liquid coats the esophagus, stomach, and small bowel. X-rays are taken at different times as the barium travels through the upper GI tract and small bowel.
  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).

Small intestine cancer treatment

Different types of treatments are available for patients with small intestine cancer 9. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.

Three types of standard treatment are used:

Surgery

Surgery is the most common treatment of small intestine cancer. One of the following types of surgery may be done:

  • Resection: Surgery to remove part or all of an organ that contains cancer. The resection may include the small intestine and nearby organs (if the cancer has spread). The doctor may remove the section of the small intestine that contains cancer and perform an anastomosis (joining the cut ends of the intestine together). The doctor will usually remove lymph nodes near the small intestine and examine them under a microscope to see whether they contain cancer.
  • Bypass: Surgery to allow food in the small intestine to go around (bypass) a tumor that is blocking the intestine but cannot be removed.

Even if the doctor removes all the cancer that can be seen at the time of the surgery, some patients may be given radiation therapy after surgery to kill any cancer cells that are left. Treatment given after the surgery, to lower the risk that the cancer will come back, is called adjuvant therapy.

Radiation therapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. There are two types of radiation therapy:

  • External radiation therapy uses a machine outside the body to send radiation toward the cancer.
  • Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer.

The way the radiation therapy is given depends on the type of the cancer being treated. External radiation therapy is used to treat small intestine cancer.

Chemotherapy

Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the cerebrospinal fluid, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). The way the chemotherapy is given depends on the type and stage of the cancer being treated.

New types of treatment are being tested in clinical trials

Not every new treatment being studied are listed here because new treatment modalities are constantly being added.

Biologic therapy

Biologic therapy is a treatment that uses the patient’s immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body’s natural defenses against cancer. This type of cancer treatment is also called biotherapy or immunotherapy.

Radiation therapy with radiosensitizers

Radiosensitizers are drugs that make tumor cells more sensitive to radiation therapy. Combining radiation therapy with radiosensitizers may kill more tumor cells.

Patients may want to think about taking part in a clinical trial.

For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.

Many of today’s standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.

Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.
Patients can enter clinical trials before, during, or after starting their cancer treatment.

Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.

Clinical trials are taking place in many parts of the country. Speak to your healthcare provider about the treatment options available including being involved as part of treatment clinical trials.

Follow-up tests may be needed.

Some of the tests that were done to diagnose the cancer or to find out the stage of the cancer may be repeated. Some tests will be repeated in order to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests.

Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your condition has changed or if the cancer has recurred (come back). These tests are sometimes called follow-up tests or check-ups.

Small Intestine Adenocarcinoma Treatment

When possible, treatment of small intestine adenocarcinoma will be surgery to remove the tumor and some of the normal tissue around it 10.

Treatment of small intestine adenocarcinoma that cannot be removed by surgery may include the following:

  • Surgery to bypass the tumor.
  • Radiation therapy as palliative therapy to relieve symptoms and improve the patient’s quality of life.
  • A clinical trial of radiation therapy with radiosensitizers, with or without chemotherapy.
  • A clinical trial of new anticancer drugs.
  • A clinical trial of biologic therapy.

Speak to your healthcare provider about the treatment options available including being involved as part of treatment clinical trials.

Small Intestine Leiomyosarcoma Treatment

When possible, treatment of small intestine leiomyosarcoma will be surgery to remove the tumor and some of the normal tissue around it.

Treatment of small intestine leiomyosarcoma that cannot be removed by surgery may include the following:

  • Surgery (to bypass the tumor) and radiation therapy.
  • Surgery, radiation therapy, or chemotherapy as palliative therapy to relieve symptoms and improve the patient’s quality of life.
  • A clinical trial of new anticancer drugs.
  • A clinical trial of biologic therapy.

Speak to your healthcare provider about the treatment options available including being involved as part of treatment clinical trials.

Recurrent Small Intestine Cancer

At the present time, no standard effective chemotherapy exists for patients with recurrent metastatic adenocarcinoma or leiomyosarcoma of the small intestine. These types of patients should be considered candidates for clinical trials evaluating the use of new anticancer drugs or biologic therapy in phase I and phase II trials 11.

Treatment of locally recurrent small intestine cancer may include the following:

  • Surgery.
  • Radiation therapy or chemotherapy as palliative therapy to relieve symptoms and improve the patient’s quality of life.
  • A clinical trial of radiation therapy with radiosensitizers, with or without chemotherapy.

Speak to your healthcare provider about the treatment options available including being involved as part of treatment clinical trials.

Gastrointestinal stromal tumor

Gastrointestinal stromal tumor is a disease in which abnormal cells form in the tissues of the gastrointestinal tract 12. Gastrointestinal stromal tumors may be malignant (cancer) or benign (not cancer) 12. They are most common in the stomach and small intestine but may be found anywhere in or near the gastrointestinal tract. Some scientists believe that gastrointestinal stromal tumors begin in cells called interstitial cells of Cajal, in the wall of the gastrointestinal tract 12.

Although they comprise fewer than 1% of all gastrointestinal tumors, gastrointestinal stromal tumor are the most common mesenchymal tumors of the gastrointestinal tract 13. It has been estimated that there are 3,300 to 6,000 new gastrointestinal stromal tumor cases per year in the United States 14. A study based on Surveillance, Epidemiology and End Results registry data found that the age-adjusted yearly incidence of gastrointestinal stromal tumor in the United States was 6.8 per million from 1992 to 2000 15. However, the true incidence is not known, in part because many tumors have not been tested for the characteristic KIT or platelet-derived growth factor receptor alpha gene mutations. In addition, small, indolent gastrointestinal stromal tumor, only a few millimeters in diameter, are common in the general population and are not included in cancer registries 16. Gastrointestinal stromal tumor are equally distributed across all geographic and ethnic groups and men and women are equally affected. Most patients present between the ages of 50 and 80 17. The vast majority of gastrointestinal stromal tumor are sporadic, but there are rare familial forms associated with the characteristic heritable mutations in the KIT gene (or, rarely, in succinate dehydrogenase genes in Carney-Stratakis syndrome). Familial gastrointestinal stromal tumor may present as multiple primary tumors.

Gastrointestinal stromal tumor may be part of a genetic syndrome, but this is rare. A genetic syndrome is a set of symptoms or conditions that occur together and is usually caused by abnormal genes. The following genetic syndromes have been linked to gastrointestinal stromal tumor:

  • Neurofibromatosis type 1 (NF1).
  • Carney triad.

Gastrointestinal stromal tumor can occur anywhere along the GI tract, but most often are found in the stomach or small intestine. The American Joint Committee on Cancer Cancer Staging Manual lists the following approximate distributions 18:

  • Stomach (60%).
  • Small intestine (30%).
  • Rectum (3%).
  • Colon (1–2%).
  • Esophagus (<1%).
  • Omentum/mesentery (rare).

Less frequently, gastrointestinal stromal tumor may arise in the appendix, gallbladder, pancreas, retroperitoneum, and paravaginal and periprostatic tissues 19. Approximately 20% to 25% of gastric gastrointestinal stromal tumor and 40% to 50% of small intestinal gastrointestinal stromal tumor are clinically aggressive 20. It has been estimated that approximately 10% to 25% of patients present with metastatic disease 21.

Signs and symptoms of gastrointestinal stromal tumors

The clinical presentation of patients with GIST varies depending on the anatomic location of the tumor and the tumor size and aggressiveness 22. The most common presentation of GIST is GI bleeding, which may be acute (melena or hematemesis) or chronic and results in anemia 20. Signs and symptoms of gastrointestinal stromal tumors include blood in the stool or vomit.

These and other signs and symptoms may be caused by a gastrointestinal stromal tumor or by other conditions. Check with your doctor if you have any of the following:

  • Blood (either bright red or very dark) in the stool or vomit.
  • Pain in the abdomen, which may be severe.
  • Feeling very tired.
  • Trouble or pain when swallowing.
  • Feeling full after only a little food is eaten.

Tests that examine the GI tract are used to detect (find) and diagnose gastrointestinal stromal tumors.

The following tests and procedures may be used:

  • Physical exam and history : An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
  • Endoscopic ultrasound and biopsy : Endoscopy and ultrasound are used to make an image of the upper GI tract and a biopsy is done. An endoscope (a thin, tube-like instrument with a light and a lens for viewing) is inserted through the mouth and into the esophagus, stomach, and first part of the small intestine. A probe at the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. This procedure is also called endosonography. Guided by the sonogram, the doctor removes tissue using a thin, hollow needle. A pathologist views the tissue under a microscope to look for cancer cells.

If cancer is found, the following tests may be done to study the cancer cells:

  • Immunohistochemistry : A test that uses antibodies to check for certain antigens in a sample of tissue. The antibody is usually linked to a radioactive substance or a dye that causes the tissue to light up under a microscope. This type of test may be used to tell the difference between different types of cancer.
  • Mitotic rate : A measure of how fast the cancer cells are dividing and growing. The mitotic rate is found by counting the number of cells dividing in a certain amount of cancer tissue.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options depend on the following:

  • How quickly the cancer cells are growing and dividing.
  • The size of the tumor.
  • Where the tumor is in the body.
  • Whether the tumor can be completely removed by surgery.
  • Whether the tumor has spread to other parts of the body.

Stages of Gastrointestinal Stromal Tumors

After a gastrointestinal stromal tumor has been diagnosed, tests are done to find out if cancer cells have spread within the gastrointestinal tract or to other parts of the body.

The process used to find out if cancer has spread within the gastrointestinal (GI) tract or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. The following tests and procedures may be used in the staging process:

  • PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.
  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
  • Chest x-ray : An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
  • Bone scan : A procedure to check if there are rapidly dividing cells, such as cancer cells, in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones and is detected by a scanner.

There are three ways that cancer spreads in the body.

Cancer can spread through tissue, the lymph system, and the blood:

  • Tissue. The cancer spreads from where it began by growing into nearby areas.
  • Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
  • Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

Cancer may spread from where it began to other parts of the body.

When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.

  • Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
  • Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.

The metastatic tumor is the same type of tumor as the primary tumor. For example, if a gastrointestinal stromal tumor (GIST) spreads to the liver, the tumor cells in the liver are actually GIST cells. The disease is metastatic GIST, not liver cancer.

The results of diagnostic and staging tests are used to plan treatment.

For many cancers it is important to know the stage of the cancer in order to plan treatment. However, the treatment of GIST is not based on the stage of the cancer. Treatment is based on whether the tumor can be removed by surgery and if the tumor has spread to other parts of the abdomen or to distant parts of the body.

Treatment is based on whether the tumor is:

  • Resectable: These tumors can be removed by surgery .
  • Unresectable: These tumors cannot be completely removed by surgery.
  • Metastatic and recurrent: Metastatic tumors have spread to other parts of the body. Recurrent tumors have recurred (come back) after treatment.
  • Recurrent GISTs may come back in the gastrointestinal tract or in other parts of the body. They are usually found in the abdomen, peritoneum, and/or liver.
  • Refractory: These tumors have not gotten better with treatment.

Treatment Options for Gastrointestinal stromal tumor

Different types of treatments are available for patients with gastrointestinal stromal tumors (GISTs). Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.

Speak to your healthcare provider about the treatment options available including being involved as part of treatment clinical trials.

Four types of standard treatment are used:

  • Surgery

If the GIST has not spread and is in a place where surgery can be safely done, the tumor and some of the tissue around it may be removed. Sometimes surgery is done using a laparoscope (a thin, lighted tube) to see inside the body. Small incisions (cuts) are made in the wall of the abdomen and a laparoscope is inserted into one of the incisions. Instruments may be inserted through the same incision or through other incisions to remove organs or tissues.

  • Targeted therapy

Targeted therapy is a type of treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells.

Tyrosine kinase inhibitors (TKIs) are targeted therapy drugs that block signals needed for tumors to grow. TKIs may be used to treat GISTs that cannot be removed by surgery or to shrink GISTs so they become small enough to be removed by surgery. Imatinib mesylate and sunitinib are two TKIs used to treat GISTs. TKIs are sometimes given for as long as the tumor does not grow and serious side effects do not occur.

  • Watchful waiting

Watchful waiting is closely monitoring a patient’s condition without giving any treatment until signs or symptoms appear or change.

  • Supportive care

If a GIST gets worse during treatment or there are side effects, supportive care is usually given. The goal of supportive care is to prevent or treat the symptoms of a disease, side effects caused by treatment, and psychological, social, and spiritual problems related to a disease or its treatment. Supportive care helps improve the quality of life of patients who have a serious or life-threatening disease. Radiation therapy is sometimes given as supportive care to relieve pain in patients with large tumors that have spread.

  • New types of treatment are being tested in clinical trials

For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.

Many of today’s standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.

Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.

Patients can enter clinical trials before, during, or after starting their cancer treatment.

Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.

Clinical trials are taking place in many parts of the country. Speak to your healthcare provider about the treatment options available including being involved as part of treatment clinical trials.

Follow-up tests may be needed.

Some of the tests that were done to diagnose the cancer or to find out the stage of the cancer may be repeated. Some tests will be repeated in order to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests.

Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your condition has changed or if the cancer has recurred (come back). These tests are sometimes called follow-up tests or check-ups.

Follow-up for GISTs that were removed by surgery may include CT scan of the liver and pelvis or watchful waiting. For GISTs that are treated with tyrosine kinase inhibitors, follow-up tests, such as CT, MRI, or PET scans, may be done to check how well the targeted therapy is working.

Resectable Gastrointestinal Stromal Tumors

Resectable gastrointestinal stromal tumors (GISTs) can be completely or almost completely removed by surgery. Treatment may include the following:

  • Surgery to remove tumors that are 2 centimeters or larger. Laparoscopic surgery may be done if the tumor is 5 cm or smaller. If there are cancer cells remaining at the edges of the area where the tumor was removed, watchful waiting or targeted therapy with imatinib mesylate may follow.
  • A clinical trial of targeted therapy with imatinib mesylate following surgery, to decrease the chance the tumor will recur (come back).

Unresectable Gastrointestinal Stromal Tumors

Unresectable GISTs cannot be completely removed by surgery because they are too large or in a place where there would be too much damage to nearby organs if the tumor is removed. Treatment is usually a clinical trial of targeted therapy with imatinib mesylate to shrink the tumor, followed by surgery to remove as much of the tumor as possible.

Metastatic and Recurrent Gastrointestinal Stromal Tumors

Treatment of GISTs that are metastatic (spread to other parts of the body) or recurrent (came back after treatment) may include the following:

  • Targeted therapy with imatinib mesylate.
  • Targeted therapy with sunitinib, if the tumor begins to grow during imatinib mesylate therapy or if the side effects are too bad.
  • Surgery to remove tumors that have been treated with targeted therapy and are shrinking, stable (not changing), or that have slightly increased in size.
  • Targeted therapy may continue after surgery.
  • Surgery to remove tumors when there are serious complications, such as bleeding, a hole in the gastrointestinal (GI) tract, a blocked GI tract, or infection.
  • A clinical trial of a new treatment.

Refractory Gastrointestinal Stromal Tumors

Many GISTs treated with a tyrosine kinase inhibitor (TKI) become refractory (stop responding) to the drug after a while. Treatment is usually a clinical trial with a different TKI or a clinical trial of a new drug.

Gastrointestinal Carcinoid Tumors

A gastrointestinal carcinoid tumor is cancer that forms in the lining of the gastrointestinal tract 23.

Gastrointestinal carcinoid tumors form from a certain type of neuroendocrine cell (a type of cell that is like a nerve cell and a hormone -making cell). These cells are scattered throughout the chest and abdomen but most are found in the gastrointestinal tract. Neuroendocrine cells make hormones that help control digestive juices and the muscles used in moving food through the stomach and intestines. A gastrointestinal carcinoid tumor may also make hormones and release them into the body.

Gastrointestinal carcinoid tumors are rare and most grow very slowly. Most of them occur in the small intestine, rectum, and appendix. Sometimes more than one tumor will form.

Health history can affect the risk of gastrointestinal carcinoid tumors.

Anything that increases a person’s chance of developing a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. Talk to your doctor if you think you may be at risk.

Risk factors for GI carcinoid tumors include the following:

  • Having a family history of multiple endocrine neoplasia type 1 (MEN1) syndrome or neurofibromatosis type 1 (NF1) syndrome.
  • Having certain conditions that affect the stomach’s ability to make stomach acid, such as atrophic gastritis, pernicious anemia, or Zollinger-Ellison syndrome.

Some gastrointestinal carcinoid tumors have no signs or symptoms in the early stages.

Signs and symptoms may be caused by the growth of the tumor and/or the hormones the tumor makes. Some tumors, especially tumors of the stomach or appendix, may not cause signs or symptoms. Carcinoid tumors are often found during tests or treatments for other conditions.

Carcinoid tumors in the small intestine (duodenum, jejunum, and ileum), colon, and rectum sometimes cause signs or symptoms as they grow or because of the hormones they make. Other conditions may cause the same signs or symptoms. Check with your doctor if you have any of the following:

Duodenum

Signs and symptoms of GI carcinoid tumors in the duodenum (first part of the small intestine, that connects to the stomach) may include the following:

  • Abdominal pain.
  • Constipation.
  • Diarrhea.
  • Change in stool color.
  • Nausea.
  • Vomiting.
  • Jaundice (yellowing of the skin and whites of the eyes).
  • Heartburn.

Jejunum and ileum

Signs and symptoms of GI carcinoid tumors in the jejunum (middle part of the small intestine) and ileum (last part of the small intestine, that connects to the colon) may include the following:

  • Abdominal pain.
  • Weight loss for no known reason.
  • Feeling very tired.
  • Feeling bloated
  • Diarrhea.
  • Nausea.
  • Vomiting.

Colon

Signs and symptoms of GI carcinoid tumors in the colon may include the following:

  • Abdominal pain.
  • Weight loss for no known reason.

Rectum

Signs and symptoms of GI carcinoid tumors in the rectum may include the following:

  • Blood in the stool.
  • Pain in the rectum.
  • Constipation.

Carcinoid syndrome may occur if the tumor spreads to the liver or other parts of the body.

The hormones made by gastrointestinal carcinoid tumors are usually destroyed by liver enzymes in the blood. If the tumor has spread to the liver and the liver enzymes cannot destroy the extra hormones made by the tumor, high amounts of these hormones may remain in the body and cause carcinoid syndrome. This can also happen if tumor cells enter the blood. Signs and symptoms of carcinoid syndrome include the following:

  • Redness or a feeling of warmth in the face and neck.
  • Abdominal pain.
  • Feeling bloated.
  • Diarrhea.
  • Wheezing or other trouble breathing.
  • Fast heartbeat.

These signs and symptoms may be caused by gastrointestinal carcinoid tumors or by other conditions. Talk to your doctor if you have any of these signs or symptoms.

Imaging studies and tests that examine the blood and urine are used to detect (find) and diagnose gastrointestinal carcinoid tumors.

The following tests and procedures may be used:

  • Physical exam and history : An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
  • Blood chemistry studies : A procedure in which a blood sample is checked to measure the amounts of certain substances, such as hormones, released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease. The blood sample is checked to see if it contains a hormone produced by carcinoid tumors. This test is used to help diagnose carcinoid syndrome.
  • Tumor marker test : A procedure in which a sample of blood, urine, or tissue is checked to measure the amounts of certain substances, such as chromogranin A, made by organs, tissues, or tumor cells in the body. Chromogranin A is a tumor marker. It has been linked to neuroendocrine tumors when found in increased levels in the body.
  • Twenty-four-hour urine test: A test in which urine is collected for 24 hours to measure the amounts of certain substances, such as 5-HIAA or serotonin (hormone). An unusual (higher or lower than normal) amount of a substance can be a sign of disease in the organ or tissue that makes it. This test is used to help diagnose carcinoid syndrome.
  • MIBG scan : A procedure used to find neuroendocrine tumors, such as carcinoid tumors. A very small amount of radioactive material called MIBG (metaiodobenzylguanidine) is injected into a vein and travels through the bloodstream. Carcinoid tumors take up the radioactive material and are detected by a device that measures radiation.
  • CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging
  • PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells.
  • Endoscopic ultrasound: A procedure in which an endoscope is inserted into the body, usually through the mouth or rectum. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. A probe at the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal tissues or organs, such as the stomach, small intestine, colon, or rectum, and make echoes. The echoes form a picture of body tissues called a sonogram. This procedure is also called endosonography.
  • Upper endoscopy : A procedure to look at organs and tissues inside the body to check for abnormal areas. An endoscope is inserted through the mouth and passed through the esophagus into the stomach. Sometimes the endoscope also is passed from the stomach into the small intestine. An endoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue or lymph node samples, which are checked under a microscope for signs of disease.
  • Colonoscopy : A procedure to look inside the rectum and colon for polyps, abnormal areas, or cancer. A colonoscope is inserted through the rectum into the colon. A colonoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove polyps or tissue samples, which are checked under a microscope for signs of cancer.
  • Capsule endoscopy : A procedure used to see all of the small intestine. The patient swallows a capsule that contains a tiny camera. As the capsule moves through the gastrointestinal tract, the camera takes pictures and sends them to a receiver worn on the outside of the body.
  • Biopsy : The removal of cells or tissues so they can be viewed under a microscope to check for signs of cancer. Tissue samples may be taken during endoscopy and colonoscopy.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options depend on the following:

  • Where the tumor is in the gastrointestinal tract.
  • The size of the tumor.
  • Whether the cancer has spread from the stomach and intestines to other parts of the body, such as the liver or lymph nodes.
  • Whether the patient has carcinoid syndrome or has carcinoid heart syndrome.
  • Whether the cancer can be completely removed by surgery.
  • Whether the cancer is newly diagnosed or has recurred.

The plan for cancer treatment depends on where the carcinoid tumor is found and whether it can be removed by surgery.

For many cancers it is important to know the stage of the cancer in order to plan treatment. However, the treatment of gastrointestinal carcinoid tumors is not based on the stage of the cancer. Treatment depends mainly on whether the tumor can be removed by surgery and if the tumor has spread.

Treatment is based on whether the tumor:

  • Can be completely removed by surgery.
  • Has spread to other parts of the body.
  • Has come back after treatment. The tumor may come back in the stomach or intestines or in other parts of the body.
  • Has not gotten better with treatment.

There are different types of treatment for patients with gastrointestinal carcinoid tumors.

Different types of treatment are available for patients with gastrointestinal carcinoid tumor. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.

Four types of standard treatment are used:

Surgery

Treatment of GI carcinoid tumors usually includes surgery. One of the following surgical procedures may be used:

  • Endoscopic resection: Surgery to remove a small tumor that is on the inside lining of the GI tract. An endoscope is inserted through the mouth and passed through the esophagus to the stomach and sometimes, the duodenum. An endoscope is a thin, tube-like instrument with a light, a lens for viewing, and a tool for removing tumor tissue.
  • Local excision: Surgery to remove the tumor and a small amount of normal tissue around it.
  • Resection: Surgery to remove part or all of the organ that contains cancer. Nearby lymph nodes may also be removed.
  • Cryosurgery: A treatment that uses an instrument to freeze and destroy carcinoid tumor tissue. This type of treatment is also called cryotherapy. The doctor may use ultrasound to guide the instrument.
  • Radiofrequency ablation: The use of a special probe with tiny electrodes that release high-energy radio waves (similar to microwaves) that kill cancer cells. The probe may be inserted through the skin or through an incision (cut) in the abdomen.
  • Liver transplant: Surgery to remove the whole liver and replace it with a healthy donated liver.
  • Hepatic artery embolization: A procedure to embolize (block) the hepatic artery, which is the main blood vessel that brings blood into the liver. Blocking the flow of blood to the liver helps kill cancer cells growing there.

Radiation therapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. There are two types of radiation therapy:

  • External radiation therapy uses a machine outside the body to send radiation toward the cancer.
  • Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer.

Radiopharmaceutical therapy is a type of internal radiation therapy. Radiation is given to the tumor using a drug that has a radioactive substance, such as iodine I 131, attached to it. The radioactive substance kills the tumor cells.

External and internal radiation therapy are used to treat gastrointestinal carcinoid tumors that have spread to other parts of the body.

Chemotherapy

Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the cerebrospinal fluid, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy).

Chemoembolization of the hepatic artery is a type of regional chemotherapy that may be used to treat a gastrointestinal carcinoid tumor that has spread to the liver. The anticancer drug is injected into the hepatic artery through a catheter (thin tube). The drug is mixed with a substance that embolizes (blocks) the artery, and cuts off blood flow to the tumor. Most of the anticancer drug is trapped near the tumor and only a small amount of the drug reaches other parts of the body. The blockage may be temporary or permanent, depending on the substance used to block the artery. The tumor is prevented from getting the oxygen and nutrients it needs to grow. The liver continues to receive blood from the hepatic portal vein, which carries blood from the stomach and intestine.

The way the chemotherapy is given depends on the type and stage of the cancer being treated.

Hormone therapy

Hormone therapy with a somatostatin analogue is a treatment that stops extra hormones from being made. GI carcinoid tumors are treated with octreotide or lanreotide which are injected under the skin or into the muscle. Octreotide and lanreotide may also have a small effect on stopping tumor growth.
Treatment for carcinoid syndrome may also be needed.

Treatment of carcinoid syndrome may include the following:

  • Hormone therapy with a somatostatin analogue stops extra hormones from being made. Carcinoid syndrome is treated with octreotide or lanreotide to lessen flushing and diarrhea. Octreotide and lanreotide may also help slow tumor growth.
  • Interferon therapy stimulates the body’s immune system to work better and lessens flushing and diarrhea. Interferon may also help slow tumor growth.
  • Taking medicine for diarrhea.
  • Taking medicine for skin rashes.
  • Taking medicine to breathe easier.
  • Taking medicine before having anesthesia for a medical procedure.

Other ways to help treat carcinoid syndrome include avoiding things that cause flushing or difficulty breathing such as alcohol, nuts, certain cheeses and foods with capsaicin, such as chili peppers. Avoiding stressful situations and certain types of physical activity can also help treat carcinoid syndrome.

For some patients with carcinoid heart syndrome, a heart valve replacement may be done.

New types of treatment are being tested in clinical trials.

Targeted therapy

Targeted therapy is a type of treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells. Several types of targeted therapy are being studied in the treatment of GI carcinoid tumors.

Patients may want to think about taking part in a clinical trial.

For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.

Many of today’s standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.

Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.

Patients can enter clinical trials before, during, or after starting their cancer treatment.

Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.

Clinical trials are taking place in many parts of the country. Speak to your healthcare provider about the treatment options available including being involved as part of treatment clinical trials.

Follow-up tests may be needed.

Some of the tests that were done to diagnose the cancer or to find out the stage of the cancer may be repeated. Some tests will be repeated in order to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests.

Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your condition has changed or if the cancer has recurred (come back). These tests are sometimes called follow-up tests or check-ups.

Carcinoid Tumors in the Small Intestine

It is not clear what the best treatment is for GI carcinoid tumors in the duodenum (first part of the small intestine, that connects to the stomach). Treatment may include the following:

  • Endoscopic surgery (resection) for small tumors.
  • Surgery (local excision) to remove slightly larger tumors.
  • Surgery (resection) to remove the tumor and nearby lymph nodes.

Treatment of GI carcinoid tumors in the jejunum (middle part of the small intestine) and ileum (last part of the small intestine, that connects to the colon) may include the following:

  • Surgery (resection) to remove the tumor and the membrane that connects the intestines to the back of the abdominal wall. Nearby lymph nodes are also removed.
  • A second surgery to remove the membrane that connects the intestines to the back of the abdominal wall, if any tumor remains or the tumor continues to grow.
  • Hormone therapy.

Clinical trials are taking place in many parts of the country. Speak to your healthcare provider about the treatment options available including being involved as part of treatment clinical trials.

Metastatic Gastrointestinal Carcinoid Tumors

Distant metastases

Treatment of distant metastases of GI carcinoid tumors is usually palliative therapy to relieve symptoms and improve quality of life. Treatment may include the following:

  • Surgery (resection) to remove as much of the tumor as possible.
  • Hormone therapy.
  • Radiopharmaceutical therapy.
  • External radiation therapy for cancer that has spread to the bone, brain, or spinal cord.
  • A clinical trial of a new treatment.

Liver metastases

Treatment of cancer that has spread to the liver may include the following:

  • Surgery (local excision) to remove the tumor from the liver.
  • Hepatic artery embolization.
  • Cryosurgery.
  • Radiofrequency ablation.
  • Liver transplant.

Clinical trials are taking place in many parts of the country. Speak to your healthcare provider about the treatment options available including being involved as part of treatment clinical trials.

Recurrent Gastrointestinal Carcinoid Tumors

Treatment of recurrent GI carcinoid tumors may include the following:

  • Surgery (local excision) to remove part or all of the tumor.
  • A clinical trial of a new treatment.

Clinical trials are taking place in many parts of the country. Speak to your healthcare provider about the treatment options available including being involved as part of treatment clinical trials.

References
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