What is venipuncture

Venipuncture is also called phlebotomy, is a procedure in which a needle is used to take blood from a vein. In many patients, venous access is necessary for obtaining blood for laboratory testing and administering fluid and intravenous drugs. Venipuncture is most often done for laboratory testing. Venipuncture may also be done to remove extra red blood cells from the blood, to treat certain blood disorders.

Blood is made up of two parts:

• Fluid (plasma or serum)
• Cells

Plasma is the fluid part that contains substances such as glucose, electrolytes, proteins, and water. Serum is the fluid part that remains after the blood is allowed to clot in a test tube.

Cells in the blood include red blood cells, white blood cells, and platelets.

Blood helps move oxygen, nutrients, waste products, and other materials through the body. It helps control body temperature, fluid balance, and the body’s acid-base balance.

Tests on blood or parts of blood may give your doctor important clues about your health.

Venipuncture test

The tourniquet application causes the inner pressure of the vein to increase artificially. If prolonged or excessive, this constriction raises the hydrostatic pressure within the vessel, forcing the water to pass into the outer connective tissue. Thereafter, the collected sample can show haemoconcentration, an activated pro-coagulant response, as well as an altered platelets function ¹. The prolonged venous stasis, which also favours tissue hypoxia, produces a change in pH which locally affects the electrolytes balance, especially potassium ².

Since potassium is mainly intracellular, a false elevation in its blood level can be easily achieved through various processes. For instance, a strenuous or prolonged fist clenching or pumping leads to the increase of extracellular potassium due to the depolarization of the skeletal muscle cells ³. Nonetheless, mechanical stress on cells can similarly induce an increase of blood potassium through a membrane leakage. In this regard there are two major mechanical causes related to phlebotomy procedure: the shear stress on red blood cells flowing through a small bore needle which causes haemolysis and the needle probing of the bloodstream which damages the tissue neighbouring the venipuncture site ⁴. Under a clinical and laboratory standpoint, the condition in which a patient is found to have hyperkalemia with no other biochemical signs or relevant causes in the medical history is said spurious or pseudohyperkalemia (pseudohyperkalemia) ⁵.

A remarkable cause of pseudohyperkalemia associated with the phlebotomy procedure is the sample cross-contamination due to tube additives. As the standard haemochromocytometric analysis is carried out on anticoagulated blood sample, the sampling tubes with di- or tri-potassium salt of the ethylenediaminetetraacetic acid (K2-EDTA and K3-EDTA) are routinely used. In this regard, it is noteworthy to address two distinct ways through which a sample can be contaminated by EDTA. If a syringe is used for drawing blood, it can happen when the blood is dispended in the tube containing the anticoagulant. In this case, the syringe’s needle is thought to carry the contamination after it has accidentally touched the inner side of the tube coated with the anticoagulant. Instead, if an evacuated tubes system is used, the contamination can be due to the anticoagulated blood which stains the inner needle that perforates the tube stop. In this regard, the order in which the tubes containing different additives are drawn is relevant to prevent contamination. According to the correct order of drawing, an EDTA-containing tube should always be collected after a serum tube or a citrate-anticoagulated whole blood tube ⁶. Noteworthy, some authors have shown that with both Sarstedt’s and evacuated tubes the recommendation of a precise tube order does not affect the blood testing ⁷. However, it should be noted that drawing an EDTA tube after all the others physically prevents any possible contamination, regardless of the way the system is used as already mentioned in this paper. With respect to pseudohyperkalemia it should be finally remarked that tube mixing, necessary to achieve the proper preservation of the collected blood, should be performed only after the tube has been removed from the holder ⁸.

Whenever an EDTA contamination happens, an abnormal reduction of serum calcium can be shown in the factitious electrolytes imbalance ⁹. Such a condition, which is defined pseudohypocalcemia (PHC), is due to the strong chelating action EDTA exerts on divalent cations and ferric iron (Fe3+). Noteworthy, the strong chelation of calcium can also interfere with coagulation testing, significantly biasing both prothrombin time (PT) and activated partial thromboplastin time (APTT) ¹⁰. Therefore, the advice to draw EDTA tubes at the end should be followed whenever any other weaker anti-coagulant is used to collect blood, as in case of lithium-heparin ¹¹.

Spurious haemolysis is another common condition associated with venipuncture, and the most frequent cause of sample unsuitability ¹². The needle bore size along with the withdrawal force is the main factors of spurious hemolysis, since them both induce a mechanical stress which causes the rupture of the cell membrane. In this regard, the needle bore size, and in turn the gauge, may be regarded as a reliable predictor of haemolysis, with 21 G needles showing half the risk of producing an unsuitable sample respect to 23 G ¹³. However, it should be noticed that the effectiveness of larger bore needles could be mitigated by the choice of the venipuncture site, and that such a lower estimated risk of haemolysis would be reliable only when the phlebotomy is performed on large veins of the antecubital fossa ¹⁴. Moreover, a 23 G needle could be as safe as a 21 G if handled correctly, whereas smaller bore size than 23 G needle should be avoided or used in very rare and extreme circumstances ¹⁵. Actually, spurious hemolysis can affect several laboratory tests as the red blood cells contain analytes which are routinely tested in serum, like lactate dehydrogenase, aspartate aminotransferase and potassium ¹⁶. Furthermore, spurious hemolysis can cause the release of haemoglobin, whose iron-containing heme group can produce a spectrophotometric interference or, in turn, can react with some of the assay reagents. It is noteworthy to mention that swabbing the venipuncture site with alcohol-containing solutions does not cause any significant haemolysis ¹⁷. Hemolysis can be readily detected by visual inspection after sample centrifugation, and directly quantified through a spectrophotometric reading even at low concentration. However, for whole blood samples, haemolysis can be neither observed nor directly measured. Nonetheless, in recent times some authors have proposed an indirect assessment of haemolysis in whole blood samples using the automated cell blood count parameters to compute suitable and reliable indexes ¹⁸.

Although not strictly related with the procedure of phlebotomy, there are some other issues which deserve a discussion, as they are among the most frequent causes of pre-analytical errors ¹⁹. The misidentification of the patient as well as the incorrect labelling of the tubes were found to be a critical step in the quality of phlebotomy with respect to the burden of preanalytical errors ²⁰. In this regard, the use of bar coding test tubes, along with the adoption of educational programs which helped to increase the compliance of the operators to the best practice guidelines, resulted successful in lowering the rate of unsuitable samples ²¹. During venipuncture, the choice of the appropriate tube to use with respect to the additive contained was another relevant factor found to significantly affect the quality of collected samples. Although the color-code scheme was devised to help the operator in recognizing the additive within the tube, the broad heterogeneity in the scheme adopted by the various manufacturers and the lack of standardization resulted in a serious issue ²². Lastly, the body positioning, which is a fundamental but often overlooked factor in laboratory preanalytics. Very recently it has been shown that changing the position from sitting to lying (and vice versa) causes a significant bias in several laboratory values, due to the gravitational adaptation which changes the hydrostatic pressure along the various body districts ²³. Noteworthy, the effect that the shift in plasma volume has on hematocrit is regarded as postural pseudoanemia for the consequence it has on haematological testing ²⁴. Although there can be several ways through which phlebotomy can affect the laboratory preanalytics, not all of them produce a significant bias as it can be seen in Table 1.

Table 1. Preanalytical bias of routine venipuncture

Footnote: Data in brackets are the actual and desirable bias respectively; “n.a.” indicates factors for which bias was not measured regardless to a significant effect may exist.

Veins of the arm for venipuncture

Large veins embedded i n the superficial fascia of the upper limb are often used to access a patient’s vascular system and to withdraw blood. The most significant of these veins are the cephalic vein, basilic vein and median cubital vein (Figure 1). The cephalic and basilic veins originate from the dorsal venous network on the back of the hand. The cephalic vein originates over the anatomical snuffbox at the base of the thumb, passes laterally around the distal forearm to reach the anterolateral surface of the limb, and then continues proximally. The cephalic vein crosses the elbow, then passes up the arm into a triangular depression-the clavipectoral triangle (deltopectoral triangle) between the pectoralis major muscle, deltoid muscle, and clavicle. In this depression, the vein passes into the axilla
by penetrating deep fascia just inferior to the clavicle.

The basilic vein originates from the medial side of the dorsal venous network of the hand and passes proximally up the posteromedial surface of the forearm. It passes onto the anterior surface of the limb just inferior to the elbow and then continues proximally to penetrate deep fascia about midway up the arm.

At the elbow, the cephalic and basilic veins are connected by the median cubital vein, which crosses the roof of the cubital fossa.

For straight forward blood tests the antecubital vein is usually the preferred site, and although it may not always be visible, it is easily palpated . The veins are simply distended by use of a tourniquet. A tourniquet should be applied enough to allow the veins to become prominent. The cephalic vein adjacent to the anatomical snuffboxis generally the preferred site for a short-term intravenous cannula.

Figure 1. Veins of the arm for venipuncture

Venipuncture sites

The ideal sites for venipuncture are typically in the cubital fossa of the forearm, which has the shape of an isosceles triangle with the biceps forming the base, and the lateral and medial groups of the antebrachial muscles forming the sides respectively ²⁶. Although in the large part of individuals the running pattern of superficial veins appears well evident in this region, the path and distribution can be irregular and may require a careful inspection before attempting the needle insertion. The main veins in this area are represented by the cephalic vein, the basilic vein, the median cubital vein, the median antebrachial vein and their various tributaries and anastomosis. Their distribution and connections can be classified into four types (1 to 4), according to the dominance of cephalic vein or basilic vein with respect to the calibre of the vessel (see Figure 2) ²⁷.

There are alternative sites for venipuncture ²⁸. They are mainly represented by the dorsal surface of the hand, where veins lay superficially because of the poor connective tissue and muscles. It must be noted that this site has also the greater pain tolerance threshold among the upper limb sites, thus resulting in the lowest perceived pain intensity ²⁹. Therefore, it may be eligible in those subjects with deep or small veins or with a particular issue of painful reactions. However, veins at this site have a greater mobility due to the poor surrounding connective tissue, and thus they more easily “roll” under the needle’s tip or collapse, causing a missed attempt or a rupture of the vessel.

Notably, it is important to know the spatial relationship between the path of veins and cutaneous nerves that can be accidentally pinched during needle insertion, causing intense pain and nerve damage ³⁰. For instance, the lateral cutaneous nerve of the forearm usually descends deeply along the cephalic vein (CV) while the medial cutaneous nerve of the forearm descends superficially along the basilic vein (BV) (Figure 3) ³¹. The most common nerve injury related to venipuncture involves the lateral antebrachial cutaneous nerve (LACN), which can lead to the so-called “causalgia” or complex regional pain syndrome ³². The complex regional pain syndrome can range from a mild and temporary harm, which resolves within few months, up to a severe and permanent damage with chronic pain and the need of complex therapies ³³. However this is a very rare consequence occurring in about 1: 25,000 individuals undergoing blood donation ³⁴. Noteworthy, the complex regional pain syndrome may be favoured by peculiar anatomical relationships between nerves and veins, as well as by the needle probing in case of a missed attempt ³⁵. However some authors have reported that the use of winged needles may contribute to lower the risk of nerve injury at the upper limb site ³⁶.

Figure 2. Variations of the cubital superficial vein

Footnote: The superficial veins of the upper limb present a certain inter-individual variability in their running pattern and caliber; A) in type 1, cephalic vein (CV) and basilic vein (BV) merge into the median antebrachial vein (MABV) of the forearm; B) in type 2, the median cubital vein (MCV) forms an anastomose between CV and BV; C) in type 3, cephalic vein (CV) is threadlike and basilic vein (BV) splits in two branches of the forearm; D) in type 4, cephalic vein (CV) and basilic vein (BV) run in parallel with no evident superficial anastomoses; the dashed triangle delimits the cubital fossa area.

Due to congenital causes, extreme leanness or in children, the brachial artery can be found to run superficially, passing closely under the ulnar side of both median cubital vein and basilic vein (Figure 3) ³⁷. In this case an excessive penetration into the vein can cause the needle to pass the vein from side to side, reaching the artery underneath. Although this happens in less than 0.01% of blood donors, it can cause sudden large hematoma with serious bleeding for the high arterial pressure, or afterwards lead to a false or true aneurism of the artery ³⁸.

Inspection and especially palpation represent the basic approach to identify the site for venipuncture ³⁹. Palpation allows phlebotomist to recognize the vessel elasticity, depth and consistency of the surrounding tissues. Superficial veins can be poorly evident to sight and palpation in some coloured or obese people, so the tourniquet must be applied several inches above the site of venipuncture in order to enhance their path by inducing venous stasis. To achieve satisfactory result, a moderate pressure (60 mm Hg) for a less than a minute is enough to suitably dilate the vein, avoiding the risk of inducing excessive venous stasis that can alter haematological and biochemical parameters. In terms of width of the venous vessel this condition corresponds to the achievement of the maximal venous cross-section area, as it is shown by the ultrasonography imaging ⁴⁰. Interestingly, an alternative to tourniquet application can be “stimulating” the vein by tapping the vessel, although its effect may be quite small on average producing just a 4% increase ⁴¹.

Figure 3. Anatomy of the venipuncture sites (the cubital fossa of right elbow)

Footnote: Topographic anatomy of the cubital fossa (cross-section at the elbow).

Blood vessels: Cephalic vein, Radial artery and Basilic vein.

Tendons: α) biceps brachii tendon; β) triceps brachii tendon);

Nerves: a) lateral antebrachial cutaneous nerve; b) medial antebrachial cutaneous nerve; c) median nerve; d) ulnar nerve; e) posterior lateral antebrachial nerve; f) radial nerve;

Muscles and bones: 1) brachioradialis; 2) brachialis; 3) pronator tenes; 4) trochlea (humerus); 5) olecranon (ulna); 6) anconeus.

Venipuncture procedure

Most of the time, blood is drawn from a vein located on the inside of the elbow or the back of the hand.

1. The site is cleaned with germ-killing medicine (antiseptic).
2. An elastic band is put around the upper arm to apply pressure to the area. This makes the vein swell with blood.
3. A needle is inserted into the vein.
4. The blood collects into an airtight vial or tube attached to the needle.
5. The elastic band is removed from your arm.
6. The needle is taken out and the spot is covered with a bandage to stop bleeding.

In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.

Sometimes, neither tourniquet nor tapping is effective. In all such cases, a technological help is provided by the trans-illuminating devices, which use the cold near infrared light-emitting diodes to light erythrocytes flowing inside the vessels ⁴². With such devices, the path of the vein appears as a colourless pattern drawn on a bright surface, as the infrared light which is absorbed by the erythrocytes is instead reflect by the neighboring tissues. In certain trans-illuminating devices the infrared image is not directly shown, but rather it is read by the device and then projected onto the skin surface to produce a guiding pattern for the operator ⁴³. Such devices have been shown to improve the venipuncture procedure without affecting haematological parameters ⁴⁴. However, they do not produce any effect over the venous cross-section area, so that small deep veins remain still hard to pierce although well visible.

Table 2. Routine venipuncture at glance

Footnotes: Roots (>) are main topics, branches (o) are relevant issues and sub-items (§, », ◊) are details.

Abbreviations: MACP = motivational anticipatory cortical process; LACN = lateral antebrachial cutaneous nerve; MACN = medial antebrachial cutaneous nerve; CV = cephalic vein; BV = basilic vein; MABV = median antebrachial vein; MCV = median cubital vein.

Venipuncture steps

The venipuncture steps you need to take before the test will depend on the kind of blood test you are having. Many tests do not require special steps.

In some cases, your health care provider will tell you if you need to stop taking any medicines before you have this test or if you need to be fasting. Do not stop or change your medicines without talking to your provider first.

Venipuncture complications

Minor complications were defined as minor bruising and hematoma at the venipuncture site. Minor bruising and hematoma (blood clot under skin) were fairly common, involving 12.3% of venipunctures, with minor bruising being the most common reaction ⁴⁵. Serious complications were defined as cellulitis, phlebitis (inflammation of vein), sweating (diaphoresis), hypotension, near syncope, syncope (fainting), and seizure activity. Serious complications were observed in 3.4% of patients ⁴⁵. Diaphoresis with hypotension occurred in 2.6%. Syncope occurred in less than 1% of patients.

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What is selective mutism

Selective mutism is a consistent failure of children to speak in certain situations, such as school, even when they can speak in other situations, such as at home with close family members. Selective mutism can interfere with school, work and social functioning. Selective mutism affects about 1 in 140 young children. Selective mutism is more common in girls and children who are learning a second language, such as those who’ve recently migrated from their country of birth.

Selective mutism is a severe anxiety disorder where a person is unable to speak in certain social situations, such as with classmates at school or to relatives they don’t see very often. However, people with selective mutism are able to speak freely to certain people, such as close family and friends, when nobody else is around to trigger the freeze response.

Selective mutism usually starts during childhood and, left untreated, can persist into adulthood. A child or adult with selective mutism doesn’t refuse or choose not to speak, they’re literally unable to speak.

If your child has selective mutism, you may notice that:

• She will not speak at times when she should, like in school. This will happen all of the time in that situation. Your child will talk at other times and in other places.
• Not speaking gets in the way of school, work, or friendships.
• This behavior lasts for at least 1 month. This does not include the first month of school because children may be shy and not talk right away.
• Your child can speak the language needed at that time. A child who does not know the language being used may not talk. This is not selective mutism.
• Your child does not have a speech or language problem that might cause her to stop talking.

The expectation to talk to certain people triggers a freeze response with feelings of panic, rather like a bad case of stage fright, and talking is impossible. In time, the person will learn to anticipate the situations that provoke this distressing reaction and do all they can to avoid them.

Associated features of selective mutism may include excessive shyness, fear of social embarrassment, social isolation and withdrawal, clinging, compulsive traits, negativism, temper tantrums, or controlling or oppositional behavior, particularly at home. There may be severe impairment in social and school functioning. Teasing or scapegoating by peers is common. Although children with this disorder generally have normal language skills, there may occasionally be an associated communication disorder (e.g., phonological disorder, expressive language disorder, or mixed receptive-expressive language disorder) or a general medical condition that causes abnormalities of articulation.

Anxiety disorders (especially social phobia), mental retardation, hospitalization, or extreme psychosocial stressors may be associated with the disorder.

Immigrant children who are unfamiliar with or uncomfortable in the official language of their new host country may refuse to speak to strangers in their new environment (which is not considered selective mutism).

Selective mutism seems to be rare, being found in fewer than 0.05 percent of children seen in general school settings. Selective mutism is slightly more common in females than in males.

Left untreated, selective mutism can lead to isolation, low self-esteem and social anxiety disorder. It can continue into adolescence and adulthood if not tackled.

However, a child can successfully overcome selective mutism if it’s diagnosed at an early age and appropriately managed.

It’s also possible for adults to overcome selective mutism, although they may continue to experience the psychological and practical effects of years deprived of social interaction or not being able to reach their academic or occupational potential.

It’s therefore important for selective mutism to be recognized early by families and schools so they can work together to reduce the child’s anxiety. Staff in early years settings and schools may receive training so they’re able to provide appropriate support.

If parents suspect their child has selective mutism and help isn’t available, or there are additional concerns – for example, their child struggles to understand instructions or follow routines – they should seek a formal diagnosis from a qualified speech and language therapist.

You can contact a speech and language therapy clinic directly or speak to a health visitor or doctor, who can refer you. Don’t accept the assurance that you or your child will grow out of it, or you or they are “just shy”.

Treating selective mutism involves behavior changes. The child’s family and school should be involved. Certain medicines that treat anxiety and social phobia have been used safely and successfully.

Incidence and Prevalence of selective mutism

The incidence of selective mutism refers to the number of new cases identified in a specified time period. Prevalence is the number of individuals who are living with selective mutism in a given time period. Accurate population estimates of selective mutism have been difficult to ascertain due to the relative rarity of the condition, differences in sampled populations, variations in diagnostic procedures (e.g., chart review, standardized assessment), and the use of different diagnostic criteria ¹.

• Recent prevalence estimates for selective mutism primarily range between 0.47% and 0.76% ², although rates as low as 0.02% ³ and as high as 1.9% ⁴ have also been reported.
• Selective mutism appears to affect more females than males by a ratio of about 1.5–2.5:1 ⁵. However, equal ratios among girls and boys have also been reported ⁶.
• Selective mutism affects approximately 1% of children being seen in behavioral health settings ⁷.
• Higher prevalence rates have been noted in immigrant children and in language-minority children than in nonimmigrant children. Accurate diagnosis of selective mutism in these populations can be difficult due to the initial nonverbal stage (i.e., “silent period”) common to second language learners ⁸.

Can my child have both selective mutism and autism?

Children with selective mutism, when they are feeling anxious, often react with lack of eye contact, a blank expression, and other behaviors that may look like an autism spectrum disorder. However, selective mutism is fundamentally different from autism; while children with autism lack social and communication skills, children with selective mutism are severely inhibited in speaking in certain situations. Selective mutism and autism can’t be diagnosed together, though some of the treatment is similar. It’s not technically possible under current American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders: DSM-5 (5th ed) ⁹ criteria to be diagnosed with both selective mutism and autism. But experts know diagnoses aren’t perfect, and it isn’t unusual for diagnoses to change as children develop. At one developmental stage a child may not look that different from his peers. At age 3, subtle differences in communication are not that easy to pick out, especially in high-functioning kids. It’s only when children are older, and start to miss developmental milestones for social behavior, social appropriateness, social connectedness, that they start to more clearly look different from their peers. Kids with selective mutism are different from those with autism spectrum disorder; in comfortable situations, selective mutism kids interact just fine, with a full range of emotion, and awareness of social interpretation. It’s only when they become uncomfortable that they fall silent. Kids on the autism spectrum disorder have a qualitative difference in how they understand and interact socially. Kids on the autism spectrum disorder have a hard time interpreting subtleties of social interaction, whether or not they’re in comfortable or uncomfortable settings. Interestingly though, in this case, the treatment that experts recommend for selective mutism isn’t that different, in approach, from what’s recommended for kids on the autism spectrum disorder, called applied behavior analysis (ABA). Applied behavior analysis is really about helping kids develop by giving positive rewards for small behaviors, broken down step-by-step. For selective mutism experts do exactly the same thing- they help kids find their voices by giving them labeled praise for small behaviors broken down into small steps they call “brave talking.” Though, to be clear, experts expect that children with those different diagnoses respond differently to treatments, and the goals and expectations are always tailored to the child’s specific strengths and challenges. So while there are a lot of parallels, the difference is in the assumptions of what kids understand or feel socially, and the expectations and goals for them. A child with autism who’s not talking may not be thinking or feeling the same thing as child with selective mutism, who is typically afraid of being judged or being ashamed. Autism makes a person think differently, you have to try to understand how a child is viewing the world in order to help him get the tools to do what he needs to do. A child on the autism spectrum may need a more explicit kind of instruction in social interaction, translation of what may be understood by others, a different kind of coaching to get him on the best possible trajectory.

Selective mutism associated difficulties

It’s important to understand how selective mutism can affect a child’s education and development, and the impact it can have on a young person’s or adult’s everyday life.

A person with selective mutism will often have other fears and social anxieties, and they may also have additional speech and language difficulties in childhood.

They’re often wary of doing anything that draws attention to them because they think that by doing so others will expect them to talk.

For example, a child may not do their best in class after seeing other children being asked to read out good work, or they may be afraid to change their routine in case this provokes comments or questions. Many have a general fear of making mistakes.

Additional difficulties can also arise from the inability to start a conversation.

Accidents and urinary infections may result from being unable to ask to use the toilet and holding on for hours at a time. School-aged children may avoid eating and drinking throughout the day so they don’t need to excuse themselves.

Children may have difficulty with homework assignments or certain topics because they’re unable to ask questions in class and seek clarification.

Teenagers may not develop independence because they’re afraid to leave the house unaccompanied. And adults may lack qualifications because they’re unable to participate in college life or subsequent interviews.

Selective mutism causes

Experts regard selective mutism as a fear (phobia) of talking to certain people. The cause isn’t always clear, but it’s known to be associated with anxiety.

The child will usually have inherited a tendency to experience anxiety and have difficulty taking everyday events in their stride.

Many children become too distressed to speak when separated from their parents and transfer this anxiety to the adults who try to settle them.

If they have a speech and language disorder or hearing problem, it can make speaking even more stressful.

Some children have trouble processing sensory information like loud noise and jostling from crowds – a condition known as sensory integration dysfunction.

This can make them “shut down” and be unable to speak when overwhelmed in a busy environment. Again, their anxiety can transfer to other people in that environment.

There’s no evidence to suggest that children with selective mutism are more likely to have experienced abuse, neglect or trauma than any other child.

When mutism occurs as a symptom of post-traumatic stress, it follows a very different pattern and the child suddenly stops talking in environments where they previously had no difficulty.

However, this type of speech withdrawal may lead to selective mutism if the triggers aren’t addressed and the child develops a more general anxiety about communication.

Another misconception is that a child with selective mutism is controlling or manipulative, or has autism. There’s no relationship between selective mutism and autism, although a child may have both.

The following factors may coexist and play a role in selective mutism:

• Associated anxiety disorders, such as social phobia, separation anxiety, and obsessive compulsive disorder ¹⁰.
• Hereditary or genetic component with a significant overlap between selective mutism and social anxiety disorder ².
• Familial links coupled with environmental factors, such as reduced opportunities for social contact, observing anxious behaviors, or reinforcing avoidance behaviors ².
• Shy or timid temperament ¹¹.

Selective mutism symptoms

Selective mutism is a type of anxiety disorder whose main distinguishing characteristic is the persistent failure to speak in specific social situations (e.g., at school or with playmates) where speaking is expected, despite speaking in other situations.

Selective mutism usually starts in early childhood, between the ages of two and four. Selective mutism is often first noticed when the child starts to interact with people outside their family, such as when they begin nursery or school.

The main warning sign is the marked contrast in the child’s ability to engage with different people, characterized by a sudden stillness and frozen facial expression when they’re expected to talk to someone who’s outside their comfort zone.

Individuals with selective mutism may present with social anxiety and social phobia. They may avoid eye contact and appear:

• nervous, uneasy or socially awkward
• rude, disinterested or sulky
• clingy
• shy and withdrawn
• stiff, tense or poorly co-ordinated
• stubborn or aggressive, having temper tantrums when they get home from school, or getting angry when questioned by parents

Symptoms of social anxiety and social phobias may include the following ¹²:

• Lack of eye contact
• Clinging to parents
• Hiding
• Running away
• Crying
• Freezing
• Tantruming if asked to speak publicly
• Avoidance of eating in public
• Anxious when having picture or video taken
• Anxious to use public restrooms

In addition to these features of social anxiety, children with selective mutism avoid initiating and participating in conversations. If they are able to express themselves, they may rely on gesturing, nodding, pointing, or whispering. They may have fears of being ignored, ridiculed, or harshly evaluated if they speak.

More confident children with selective mutism can use gestures to communicate – for example, they may nod for “yes” or shake their head for “no”.

But more severely affected children tend to avoid any form of communication – spoken, written or gestured.

Some children may manage to respond with a word or two, or they may speak in an altered voice, such as a whisper.

Few people see the child or young person as they really are – a sensitive, thoughtful individual who’s chatty, outgoing and fun-loving when relaxed and unaffected by their selective mutism.

Selective mutism diagnosis

Selective mutism interferes with educational or occupational achievement or with social communication, and in order for it to be diagnosed, it must last for at least 1 month and is not limited to the first month of school (during which many children may be shy and reluctant to speak). Selective mutism should not be diagnosed if the individual’s failure to speak is due solely to a lack of knowledge of, or comfort with, the spoken language required in the social situation. It is also not diagnosed if the disturbance is accounted for by embarrassment related to having a communication disorder (e.g., stuttering) or if it occurs exclusively during a pervasive developmental disorder, schizophrenia, or other psychotic disorder. Instead of communicating by standard verbalization, children with this disorder may communicate by gestures, monosyllabic, short, or monotone utterances, or in an altered voice.

Older children may also need to see a mental health professional or school educational psychologist.

Adults will ideally be seen by a mental health professional with access to support from a speech and language therapist or another knowledgeable professional.

The clinician may initially want to talk to parents without their child present, so they can speak freely about any anxieties they have about their child’s development or behavior.

They’ll want to find out whether there’s a history of anxiety disorders in the family, and whether anything is causing distress, such as a disrupted routine or difficulty learning a second language. They’ll also look at behavioral characteristics and take a full medical history.

A person with selective mutism may not be able to speak during their assessment, but the clinician should be prepared for this and be willing to find another way to communicate.

For example, they may encourage a child with selective mutism to communicate through their parents, or suggest that older children or adults write down their responses or use a computer.

Selective mutism is diagnosed according to specific guidelines. These include observations about the person concerned as outlined:

• they don’t speak in specific situations, such as during school lessons or when they can be overheard in public
• they can speak normally in situations where they feel comfortable, such as when they’re alone with parents at home, or in their empty classroom or bedroom
• their inability to speak to certain people has lasted for at least a month (two months in a new setting)
• their inability to speak interferes with their ability to function in that setting
• their inability to speak isn’t better explained by another behavioral, mental or communication disorder

Selective mutism falls within the category of Anxiety Disorders ¹³. According to the fifth edition of the American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-5) ¹⁴, the diagnostic criteria for selective mutism are as follows:

• The child shows consistent failure to speak in specific social situations in which there is an expectation for speaking (e.g., at school), despite speaking in other situations.
• The disturbance interferes with educational or occupational achievement or with social communication.
• The duration of the disturbance is at least 1 month (not limited to the first month of school).
• The failure to speak is not attributable to a lack of knowledge of, or comfort with, the spoken language required in the social situation.
• The disturbance is not better explained by a communication disorder (e.g., child-onset fluency disorder) and does not occur exclusively during the course of autism spectrum disorder, schizophrenia, or another psychotic disorder.

These behaviors are a method of self-protection during an experience of intense anxiety but may appear deliberately oppositional ¹⁵.

Selective mutism test

There is no test for selective mutism. Diagnosis is based on the person’s history of symptoms.

Teachers and counselors should consider cultural issues, such as recently moving to a new country and speaking another language. Children who are uncertain about speaking a new language may not want to use it outside of a familiar setting. This is not selective mutism.

The person’s history of mutism should also be considered. People who have been through trauma may show some of the same symptoms seen in selective mutism.

Selective mutism treatment

With appropriate management and treatment, most children are able to overcome selective mutism. But the older they are when the condition is diagnosed, the longer it will take.

The effectiveness of treatment will depend on:

• How long the person has had selective mutism
• Whether or not they have additional communication or learning difficulties or anxieties
• The co-operation of everyone involved with their education and family life

Treatment doesn’t focus on the speaking itself, but reducing the anxiety associated with speaking.

This starts by removing pressure on the person to speak. They should then gradually progress from relaxing in their school, nursery or social setting, to saying single words and sentences to one person, before eventually being able to speak freely to all people in all settings.

The need for individual treatment can be avoided if family and staff in early years settings work together to reduce the child’s anxiety by creating a positive environment for them.

This means:

• Not letting the child know you’re anxious
• Reassuring them that they’ll be able to speak when they’re ready
• Concentrating on having fun
• Praising all efforts the child makes to join in and interact with others, such as passing and taking toys, nodding and pointing
• Not showing surprise when the child speaks, but responding warmly as you would to any other child

As well as these environmental changes, older children may need individual support to overcome their anxiety.

The most effective types of treatment are behavioral therapy and cognitive behavioral therapy (CBT). These are described below, along with some commonly used techniques to overcome anxiety.

Behavioral therapy

behavioral therapy is designed to work towards and reinforce desired behaviors while replacing bad habits with good ones.

Rather than examining a person’s past or their thoughts, it concentrates on helping combat current difficulties using a gradual step-by-step approach to help conquer fears.

Several of the techniques below can be used at the same time by individuals, family members and school or college staff, possibly under the guidance of a speech and language therapist or psychologist.

Stimulus fading

In stimulus fading, the person with selective mutism communicates at ease with someone, such as their parent, when nobody else is present.

Another person is introduced into the situation and, once they’re included in talking, the parent withdraws. The new person can introduce more people in the same way.

Positive and negative reinforcement

Positive and negative reinforcement involves responding favorably to all forms of communication and not inadvertently encouraging avoidance and silence.

If the child is under pressure to talk, they’ll experience great relief when the moment passes, which will strengthen their belief that talking is a negative experience.

Desensitization

Desensitization is a technique that involves reducing the person’s sensitivity to other people hearing their voice by sharing voice or video recordings.

For example, email or instant messaging could precede an exchange of voice recordings or voicemail messages, leading to more direct communication, such as telephone or online conversations.

Shaping

Shaping involves using any technique that enables the person to gradually produce a response that’s closer to the desired behavior.

For example, starting with reading aloud, then taking it in turns to read, followed by interactive reading games, structured talking activities and, finally, two-way conversation.

Graded exposure

In graded exposure, situations causing the least anxiety are tackled first. With realistic targets and repeated exposure, the anxiety associated with these situations decreases to a manageable level.

Older children and adults are encouraged to work out how much anxiety different situations cause, such as answering the phone or asking a stranger the time.

Cognitive behavioral therapy

Cognitive behavioral therapy (CBT) works by helping a person focus on how they think about themselves, the world and other people, and how their perception of these things affects their thoughts and feelings. CBT also challenges fears and preconceptions through graded exposure.

Cognitive behavioral therapy (CBT) is carried out by mental health professionals and is more appropriate for older children, adolescents – particularly those experiencing social anxiety disorder – and adults who’ve grown up with selective mutism.

Younger children can also benefit from cognitive behavioral therapy-based approaches designed to support their general wellbeing.

For example, this may include talking about anxiety and understanding how it affects their body and behavior, and learning a range of anxiety management techniques or coping strategies.

Medication

Medication is only really appropriate for older children, teenagers and adults whose anxiety has led to depression and other problems.

Medication should never be prescribed as an alternative to the environmental changes and behavioral approaches described above.

However, antidepressants may be used alongside a treatment programme to decrease anxiety levels and speed up the therapy process, particularly if previous attempts to engage the individual in treatment have failed.

How to help a child with selective mutism

You may find the advice below helpful if your child has been diagnosed with selective mutism.

• Don’t pressurize or bribe your child to encourage them to speak.
• Let your child know you understand they’re scared to speak and have difficulty speaking at times. Tell them they can take small steps when they feel ready and reassure them that talking will get easier.
• Don’t praise your child publicly for speaking because this can cause embarrassment. Wait until you’re alone with them and consider a special treat for their achievement.
• Reassure your child that non-verbal communication, such as smiling and waving, is fine until they feel better about talking.
• Don’t avoid parties or family visits, but consider what environmental changes are necessary to make the situation more comfortable for your child.
• Ask friends and relatives to give your child time to warm up at his or her own pace and focus on fun activities rather than getting them to talk.
• As well as verbal reassurance, give them love, support and patience.

Getting help and support

It’s only relatively recently that selective mutism has been properly understood and effective treatment approaches have been developed.

The body of expertise among healthcare professionals, educational psychologists and teaching staff is growing, but those seeking help need to be prepared for the fact that professionals in their area may not have up-to-date knowledge or experience of working with selective mutism.

If this is the case, you should seek out teachers and healthcare professionals who are willing to listen, learn and develop their specialist knowledge to provide appropriate support.

Teenagers and adults with selective mutism can find information and support at iSpeak (http://www.ispeak.org.uk/) and Finding Our Voices (https://findingourvoices.co.uk/).

The following organizations are good resources for finding professionals for treating selective mutism:

• American Speech-Language-Hearing Association (https://www.asha.org/profind/)
• Selective Mutism Association (https://www.selectivemutism.org/)
• The Royal College of Speech and Language Therapists (https://www.rcslt.org/speech-and-language-therapy)
• The Association of Speech and Language Therapists in Independent Practice (https://beta.helpwithtalking.com/)

Selective mutism prognosis

Children with selective mutism can have different outcomes. Some may need to continue therapy for shyness and social anxiety into the teenage years, and possibly into adulthood.

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