Introduction
A thorough history should draw the practitioner’s attention to potential medical emergencies that could occur, and there- fore facilitate taking appropriate steps to prevent them from happening. One example might be the prompt treatment of a diabetic patient at a predictable time, thereby preventing hypoglycaemia.
In the history, it is important to enquire about known allergies or adverse reactions to medication, so that these can be avoided.
In all emergency situations, the basic principles of resusci- tation should be remembered, and the ‘ABCDE approach’ to the sick patient used in all cases (discussed in the following text). Key points in the management of medical emergencies are listed in Table 21.2. All medical emergencies and near misses should be documented
The ABCDE approach to the sick patient
All sick patients should be managed using the ABCDE approach. Here is a summary of the approach:
▪ A = Airway.
▪ B = Breathing.
▪ C = Circulation.
▪ D = Disability.
▪ E = Exposure.
The airway should be opened by using a head tilt/chin lift method, or by using a jaw thrust method to push the mandible forward (see Figures 21.1 and 21.2). The latter should be used in cases of known or suspected cervical spine injury, or in cases of cervical spine fusion or immobility.
Breathing should be checked by the look–listen–feel method for 10 seconds.
The concept of checking for circulation is not mandatory for dental practitioners, as the sign to start resuscitation is the absence of breathing, or the presence of the so‐called ‘agonal gasp breathing’. If competent, at the same time as checking for breathing, a central pulse such as the carotid pulse can be checked.
Disability refers to the neurological status of the patient, and this can be checked using the ‘AVPU method’, summarised as follows:
▪ A = Alert – Is the patient responsive?
▪ V = Voice – Does the patient respond to verbal stimuli?
▪ P = Pain – Does the patient respond to a painful stimulus?
▪ U = Unresponsive.
Exposure refers to the appropriate exposing of a part of the patient’s body for a defined purpose. One example might be the application of chest pads of an automated external defibrillator (AED). Other purposes include examining for a rash in an allergic reaction and examining for traumatic injuries.
When using the ABCDE approach, it is important to remember not to move on to the next stage before the previous stage has been completed. For example, there is no point in moving from the airway stage until the airway has been ade- quately opened, as the other aspects will ultimately be futile. Likewise, it is important to return if necessary to the start of the process if circumstances change.
The collapsed patient
The most common cause of loss of consciousness in dental prac- tice is vasovagal syncope (fainting). If recovery is not rapid after appropriate treatment, other possibilities should be considered, such as myocardial infarction (MI), bradycardia, heart block, stroke, hypoglycaemia or anaphylaxis. If the cause of collapse is uncertain, the steps outlined in Table 21.3 should be followed in a patient who may or may not have lost consciousness
Fainting (vasovagal syncope)
Fainting is the most common medical emergency seen in dental practice. Pain and anxiety are predisposing factors.
Signs and symptoms
The patient may:
▪ Feel nauseated, with cold, clammy skin.
▪ Notice a visual disturbance, together with a feeling of dizziness.
▪ Have a pulse initially rapid and weak, becoming slow on recovery.
▪ Lose consciousness
Management
▪ Before the patient loses consciousness, the possibility of hypoglycaemia should be borne in mind and a glucose drink may be helpful.
▪ Lay the patient flat, so that the legs are higher than the head (and heart).
▪ Loosen any tight clothing around the neck.
▪ Recovery is usually rapid; as the patient regains conscious- ness, his or her body may occasionally jerk in a manner resembling a fit. Prolonged unconsciousness should lead to consideration of other causes of collapse
Chest pain
Most patients who experience chest pain of cardiac origin in the dental environment are likely to have a previous history of cardiac disease. Again, the history is important, as is recognis- ing the risk factors for cardiovascular disease (Chapter 5, titled ‘Cardiovascular disorders’).
It is important for patients who use medication to control angina to have this with them, or to ensure that it is readily available in the emergency kit in case they need it. Likewise, it is important for the patients to have taken their normal medications.
Some features make the pain unlikely to be cardiac in ori- gin, such as: pains that, however, severe last less than 30 seconds; stabbing pains; well‐localised left submammary pain; and pains that continually vary in location. A chest pain that is made better by stopping exercise is more likely to be cardiac in origin than one that is not related. Pleuritic pain is sharp and made worse on inspiration – for example, following pulmonary embolism. Oesophagitis may cause a retrosternal pain that is worse on bending or lying down. Oesophageal pain, as with cardiac pain, may be relieved by sublingual nitrates – for example, GTN
Hyperventilation may produce chest pain. Gall bladder and pancreatic pain may also mimic cardiac pain. Musculoskeletal pain is often accompanied by tenderness to palpation in the affected region. A summary of the main possible causes of chest pain is listed in Table 21.4.
Clearly, it is important to exclude angina and MI when a patient complains of chest pain.
Signs and symptoms
▪ The pain of angina and MI may be very similar, comprising a crushing central chest pain (like a tight band around the chest) radiating to the left arm (usually) or mandible.
▪ Angina is usually relieved by the patient’s medication, which in most cases will be a GTN spray. The pain of angina usu- ally lasts for <3 min if GTN is used.
▪ MI is often accompanied by other symptoms such as sweat- ing, nausea and palpitations, and is not relieved by GTN.
▪ There may be breathlessness and vomiting.
▪ Occasionally, a patient may lose consciousness.
Management
A calm and reassuring manner from the practitioner is important.
▪ If the patient has a history of angina, get the patient to use his or her normal medication – there should be a rapid response (within a few minutes) if the cause is angina. GTN should be part of the emergency drug box in case patients do not have their own medications with them.
▪ If MI is suspected, summon help at an early stage, and administer 300 mg aspirin to be chewed (if not contraindicated).
▪ The patient will be most comfortable in a sitting position.
▪ Ensure that the airway is maintained, and administer a 50/50 mix of nitrous oxide and oxygen, which has analgesic and anxiolytic effects, or 15 litres per minute oxygen.
A patient who has had a MI may be given one of the so‐called ‘clot busting’ agents, such as streptokinase. There are strict cri- teria regarding the types of patients in whom this medication should be used, since widespread bleeding may result. As a consequence of this, a patient who has undergone recent sur- gery should be excluded. More recent management advances include immediate angioplasty, in situations where the neces- sary facilities and expertise are available.
The diabetic patient
A history of recurrent hypoglycaemic episodes and mark- edly varying blood glucose levels means that a patient attending for dental treatment is much more likely to develop hypoglycaemia. It is wise to treat diabetic patients first in the morning, ensuring that they have had their normal antidiabetic medication and something to eat prior to attending the surgery.
Hypoglycaemia is much more likely to be encountered in dental practice than hyperglycaemia, since the former has a more rapid onset. Principally seen in diabetics, hypoglycaemia may be seen in very anxious patients who have starved them- selves for whatever reason prior to attending the dental treatment session. Diabetic control may be adversely affected by oral sepsis, leading to increased risk of complications.
Diabetic emergencies
If hypoglycaemia occurs, glucose should be given orally – as tablets, syrup or sugary drinks – if the patient can cooperate. For those patients who are not able to cooperate, glucose is also available as an oral gel in a dispenser (e.g. GlucoGelR). If these measures are impossible or ineffective – for example, in an uncooperative, semi‐conscious or comatose patient – the usual treatment of first choice is glucagon (1 mg/ml injection) 1 mg, intramuscular or subcutaneous. Patients who do not respond to glucagon, or who have been hypoglycaemic for some time and may have exhausted their supplies of liver gly- cogen, will require up to 50 ml of intravenous glucose solution. Clearly, patients who have reached this stage should be man- aged under medical supervision, and are unlikely to be seen in dental practice
Signs and symptoms
▪ Uncharacteristic aggression.
▪ Drowsiness.
▪ Moist skin.
▪ Rapid, full pulse.
▪ Low blood sugar.
Management
▪ Lie the patient flat.
▪ If the patient is conscious, give oral glucose (four lumps of sugar) or GlucoGel®.
▪ If the patient is unconscious, give 1 mg of glucagon intra- muscularly. (Glucagon is more easily administered than intravenous glucose.)
▪ Get medical help.
The mainstay of hyperglycaemia treatment is intravenous rehy- dration, which requires medical intervention and is beyond the scope of this discussion.
Hypersensitivity reactions – anaphylaxis
Anaphylaxis is a type I severe hypersensitivity reaction. In dentistry, the most common cause is penicillin or latex, but NSAIDs can also cause this. Rarely, local anaesthetics may be responsible.
Signs and symptoms
▪ Facial flushing/pallor/cyanosis/oedema.
▪ Skin cold and clammy.
▪ Urticaria (itchy rash), oedema.
▪ Wheezing/laryngospasm.
▪ Tachycardia, hypotension.
Second‐line’ drugs – not required to be administered by dental practitioners
▪ 10–20 mg chlorphenamine (antihistamine) intravenously (if competent).
▪ 100 mg of hydrocortisone sodium succinate intravenously, which helps to reduce oedema and stabilises mast cells (if competent).
▪ An inhaled β2‐agonist can be useful to facilitate bronchodi- lation.
▪ Arrange for hospital admission, as there may be a rebound attack.
Chlorphenamine and hydrocortisone need not be given by non‐medical first responders. If the practitioner is confident in drug administration, it will do no harm to administer these drugs. Whatever the status of the resuscitator, adrenaline must be given (the preferred injection site is shown in Figure 21.4, but the deltoid muscle may also be used).
Many patients with a history of anaphylactic reactions will carry an ‘EpiPen’, which contains 300 µg of epinephrine.
Angioedema
Angioedema is triggered when mast cells release histamine and other chemicals (essentially vasoactive peptides) into the blood, producing rapid swelling. From a medical perspective, angioedema is life‐threatening if the swelling produced com- promises the airway. It may be precipitated by substances such as latex, as well as by drugs – including penicillin, NSAIDs and ACE inhibitors (e.g. captopril and lisinopril). There is a hereditary component to angioedema.
Swelling of the skin occurs, especially around the eyes and lips, but also in the throat and on the extremities. Laryngeal oedema and bronchospasm lead to the same clinical situation as anaphylaxis. In cases of severe angioedema, patients may be prescribed the steroid prednisolone. Acute allergic oedema of this type can develop alone, or may be associated with anaphy- lactic reactions.
Hereditary angioedema (HANE) is caused by continued complement activation, resulting from a deficiency of the inhibitor of the enzyme C1 esterase. The inheritance is usually autosomal dominant, and may not present until adult life. C1 esterase inhibitor concentrates are available to supplement the deficiency. Such supplements should be administered prior to dental treatment if such treatment has, in the past, triggered the onset of angioedema.
Fits
The nature of the fits (seizures), their frequency and degree of control, including the type of medication used, are all impor- tant factors to be elicited.
Signs and symptoms
The signs and symptoms of fits vary widely, depending on the underlying cause. An obvious fit is easily recognised.
Management
▪ In most cases, the main aim is to prevent patients from injuring themselves during fits episodes.
▪ If a fits episode has stopped and the patient is in the imme- diate aftermath (‘post‐ictal phase’), he or she should be placed in the recovery position.
▪ If the convulsions are ongoing, buccal administration of midazolam buccal solution (10 mg) should be carried out after 5 minutes of continuous seizure.
▪ The possibility of the patient’s airway becoming occluded should always be kept in mind, and the airway must there- fore be protected.
It may be appropriate to abort dental treatment if a patient suffers a fits episode during treatment.
Cardiac arrest
Cardiac arrest is denoted by the absence of a pulse and breathing.
Possible causes of cardiac arrest
▪ MI.
▪ Choking.
▪ Bleeding.
▪ Drug overdose.
▪ Hypoxia.
Signs and symptoms
▪ The patient loses consciousness.
▪ There is no respiration or pulse.
Management
Basic life support (BLS) implies that no equipment is employed other than a protective airway device. It has been suggested that cardiopulmonary resuscitation (CPR) can be performed effectively in the dental chair, but it is important that this is confirmed in each case.
Interruptions to chest compression in resuscitation are com- mon, and are associated with a reduced chance of survival. The ideal situation is to be able to deliver continuous chest compres- sions while giving ventilations independently. This is only possible, however, when an advanced airway is placed. Chest‐ compression‐only CPR is another way to increase the number of compressions, but is only effective for a period of about 5 min. For this reason, this technique is not recommended as standard management. The principle that compression‐only CPR works upon is that, during the first few minutes after a non‐asphyxial cardiac arrest, the blood oxygen content remains high, and, therefore, ventilation is less important than chest compression at this stage.
Rescuers are now taught to place the heel of their one hand in the centre of the chest (sternum), with the other hand on top. The chest should be compressed at a rate of about 100/min.
The basic algorithm for adult basic life support is given in Figure 21.5. 
In guidelines published by the Resuscitation Council (UK), the concept of checking for ‘signs of a circulation’ was introduced. This change from previous regulations was made because it had been found that checking the carotid pulse to diagnose cardiac arrest could be unreliable, sometimes even when attempted by healthcare professionals. In the current guidelines, an absence of breathing is the main sign of car- diac arrest. Also highlighted is the need to identify agonal gasps (in addition to the absence of breathing) as a sign to commence CPR.
In the new guidelines, it is still stressed that, before resusci- tation attempts are made, the environment should be ensured to be safe.
Use of defibrillation
Ventricular fibrillation (VF) is the most common cause of cardiac arrest. It is a rapid and chaotic rhythm. As a result, the heart is unable to contract, and thus unable to sustain its function as a pump
‘Defibrillation’ is a term that refers to the termination of fibrillation. It is achieved by administering a controlled electri- cal shock to the heart that may restore an organised rhythm, enabling the heart to contract effectively. It is now well recog- nised that early defibrillation is important. The only effective treatment for VF is defibrillation, and the sooner the shock is given, the greater the chance of survival.
The provision of defibrillation has been made easier by the development of AEDs. AEDs are sophisticated, reliable and safe computerised devices that use voice and visual prompts to guide rescuers, and are suitable for use by healthcare professionals as well as lay people. The devices analyse the victim’s rhythm, determine the need for a shock and then deliver a shock. The AED algorithm is given in Figure 21.6.
Pacemakers
Pacemakers are used to treat certain types of arrhythmias, one example being bradycardia. Some devices used in dentistry can interfere with the normal functioning of pace- makers. Such devices include some types of ultrasonic scalers, electroanalgesic devices, electrocautery devices and electronic apex locaters. It is important that the relevant literature supplied by the manufacturers of such devices be consulted.
If a patient with a pacemaker develops bradycardia, all elec- trical equipment should be switched off, and the patient placed supine with the legs raised. Immediate medical assistance should be summoned.
Asthma
It is important to get an idea of the severity of the condition, which will usually come from the history. Important facts to ascertain are the effectiveness of medication, precipitating factors, hospital admissions due to asthma and the use of systemic steroids.
It is important that asthmatic patients bring their usual inhalers/medication with them to dental appointments. If the inhaler has not been brought, it must be in the emergency kit, or treatment should be deferred. If the asthma is in a particularly severe phase, elective treatment may be best postponed. Drugs that may be prescribed by dental practitioners, particularly NSAIDs, may worsen asthma, and are therefore best avoided.
Signs and symptoms
▪ The patient is breathless with an expiratory wheeze, and may be using the accessory muscles of respiration.
▪ The patient will usually be tachycardic. Bradycardia is a worrying sign.
Management
▪ A calm and reassuring manner from the practitioner is important.
▪ The patient will be most comfortable in a sitting position.
▪ The patient should use his or her normal asthma medication.
▪ Oxygen should be administered.
▪ Further inhalation should be via a spacer device filled with 12 actuations of the inhaler.
▪ If the attack does not respond rapidly when using only the patient’s usual medication, he or she should be admitted to the hospital.
The use of a spacer device improves delivery of the patient’s own inhaler contents. The method described in the British National Formulary is to apply the mouthpiece of the inhaler to the underside of a paper cup, through which a hole has been cut. If the open end of the cup is placed against the mouth and nose, aerosol delivery should be improved
Hyperventilation
Hyperventilation is a more common emergency than is often thought. When hyperventilation persists, it is extremely dis- tressing to the patient. Anxiety is the principal precipitating factor.
Signs and symptoms
▪ The patient may feel weak and light‐headed or dizzy.
▪ They may complain of paraesthesia (e.g. in the hands), or complain of muscle pain.
▪ They may have palpitations and chest pain, and indeed are sometimes convinced that they are having an MI.
▪ Carpopedal spasm may occur if hyperventilation is pro- longed (Figure 21.7).
Management
▪ Clearly, a calm and sympathetic approach by the practi- tioner is important.
▪ The diagnosis is not always as obvious as it may seem.
▪ When other causes for the symptoms have been excluded, the patient should be encouraged to rebreathe their own exhaled air, so as to increase the amount of carbon diox- ide being inhaled. Hyperventilation leads to carbon dioxide being ‘washed out’ of the body, thus producing an alkalosis. Rebreathing exhaled air returns the situa- tion to normal. This is achieved by breathing in and out of a paper bag held over the mouth and nose. A spacer device can be used for rebreathing exhaled air with the end blocked off where the inhaler would normally be placed.
Choking
A foreign body may lead to either mild or severe airway obstruction. Signs and symptoms that aid in differentiation are listed in Table 21.5, which is taken from the Resuscitation Council (UK) guidelines. In the conscious victim, it is useful to ask the question ‘Are you choking?’. 
An algorithm for the management of choking patients has been published by the Resuscitation Council (UK). This is shown in Figure 21.8. The back blows shown in the algorithm are given by standing to the side of the victim and slightly behind. The chest should be supported with one hand, and the victim should lean well forward, so that, when the obstruction is dislodged, it is expelled from the mouth, rather than passed further down the airway. Up to five sharp blows should be given between the shoulder blades with the heel of the other hand. After each back blow, a check should be made to see if the obstruction has been relieved. 
If the back blows fail to relieve the obstruction, up to five abdominal thrusts should be given. The method is as follows:
▪ Stand behind the victim, put both arms around the upper part of his or her abdomen, and lean the victim forward.
▪ The rescuer’s fist should be clenched and placed between the umbilicus and the lower end of the sternum.
▪ The clenched fist should be grasped with the other hand and pulled sharply inwards and upwards.
▪ This should be repeated up to five times
▪ If the obstruction is not relieved, an alternating pattern of five back blows with five abdominal thrusts should be used.
Other aspects of the management of inhaled foreign bodies are discussed in Chapter 6, titled ‘Respiratory disorders’
Adrenal crisis
Adrenal crisis may result from adrenocortical hypofunction, leading to hypotension, shock and death. It may be precipi- tated by stress induced by trauma, surgery or infection.
Adrenocortical hypofunction may be primary or second- ary. An example of primary hypotension is Addison’s disease (see Chapter 12, titled ‘Dermatology and mucosal lesions’), in which there are circulating autoantibodies to the adrenal cortex. This results in atrophy and failure of secretion of hydrocortisone and aldosterone. Tuberculous destruction of the adrenal glands will produce the same effect.
Secondary hypoadrenocorticism results from adrenocorti- cal hypofunction, owing to ACTH deficiency. This happens due to the suppression of adrenocortical function following the use of systemic corticosteroids.
The use of supplemental steroids prior to dental surgery in patients at risk of an adrenal crisis is a contentious issue. The rationale for steroid supplementation is as follows. A normal physiological response to trauma is to increase corticosteroid production in response to stress. If this response is absent, hypotension, collapse and death will occur. The hypothalamo– pituitary–adrenal axis will fail to function if either the pituitary or adrenal cortex ceases to function for the reasons mentioned in the preceding text. This happens in secondary hypoadreno- corticism, since administration of corticosteroids leads to negative feedback to the hypothalamus, causing decreased ACTH production and adrenocortical atrophy. This atrophy means that an endogenous steroid boost cannot be produced in response to stress. Studies have suggested that dental surgery may not require supplementation. However, more invasive procedures, such as third molar surgery, may still require cover. It is wise, if sup- plementary steroids have not been used, to monitor the blood pressure of patients taking steroids. If the diastolic pressure falls by >25%, then an intravenous steroid injection (100 mg of hydrocortisone) is indicated. Patients who may require supple- mentation are those who are currently taking corticosteroids or have done so in the last month. A supplement may also be required if steroid therapy has been used for >1 month in the previous year. If the patient is receiving the equivalent of 20 mg of prednisolone daily, then extra supplementation is not likely to be required
Signs and symptoms
▪ The patient loses consciousness.
▪ The patient has a rapid, weak or impalpable pulse.
▪ The patient’s blood pressure falls rapidly.
Management
▪ Lie the patient flat.
▪ Ensure a clear airway and administer oxygen, 15 litres per minute, via a non‐rebreathe mask.
▪ Call an ambulance or dial the hospital emergency number.
▪ Administer 200 mg (at least) of hydrocortisone sodium suc- cinate intravenously (if competent).
Local anaesthetics emergencies
Allergy to local anaesthetics is rare, but should be managed similar to any other case of anaphylaxis. When taken in the context of the number of local anaesthetics administered, com- plication rates are low, but can occur. The signs and symptoms cover the whole range of allergies up to those of anaphylaxis.
Fainting in association with the injection of local anaes- thetics is rather more common, and can usually be avoided by administering local anaesthetics while the patient is supine. Intravascular injection of local anaesthetics can be avoided by the use of an aspirating syringe. An intravascular injection may induce agitation, drowsiness or confusion, with fits and, ulti- mately, loss of consciousness.
Cardiovascular problems in association with local anaesthetics
The most common symptoms to be precipitated are palpita- tions, which will subside naturally with time. An MI may rarely be precipitated in a susceptible patient.
It is possible for interactions with antihypertensive drugs to precipitate hypotension. It is important in these circumstances to ensure that the airway remains clear, and that the patient is
reassured. Medical assistance should be sought. Hypertension should likewise be managed with medical assistance.
In any circumstances in which a cardiovascular event is pre- cipitated, treatment should be deferred for another occasion (see also Chapter 14, titled ‘Pain and anxiety control’).
Temporary facial palsy or diplopia
Complications such as these arise from the local anaesthetics agent tracking towards the facial nerve or the orbital contents. The patient should be reassured, since the effects wear off as the effects of the local anaesthetics diminish. If the temporal and zygomatic branches of the facial nerve are involved, it is important to protect the cornea, and an eye patch is indicated as a temporary measure.
Stroke
Stroke is discussed in detail in Chapter 9 (titled ‘Neurology and special senses’). It is unlikely that a patient will have a stroke in dental surgery; nevertheless, it is still possible. Signs and symptoms vary according to the area of the brain affected.
There may be loss of consciousness, and/or weakness of the limb(s) on one side of the body. The side of the face may be weak; if so, this will be an upper motor neurone lesion, and therefore the forehead will not be affected on that side.
The dental surgeon’s role, if such an event occurred, would be to first recognise (or suspect) the possibility. There is an ongoing public education programme regarding early stroke recognition using the acronym ‘FAST’, denoting:
▪ Face drooping.
▪ Arm weakness.
▪ Speech difficulty.
▪ Time to call emergency services.
Initial management would involve employing the ABCDE approach, and avoidance of aspiration of secretions as part of this, as well as calling for emergency help. Clearly, ongoing management would be the province of the specialist.
Needle breakage
Needle breakages are rare with modern needles. When they do happen, they often occur at the hub of the needle, and are more common with needles of smaller diameter. If this event does occur, the needle should be retrieved immediately if pos- sible using fine artery forceps. This is only possible if the needle is not inserted to the hub while the injection is given, and, for this reason, the needle should not be inserted to this degree on any occasion
If immediate retrieval is not possible, the patient should be informed about what has happened and referred immedi- ately to the local maxillofacial unit. It is important for medicolegal reasons that the incident be accurately and clearly documented
Sedation emergencies
Sedation emergencies are usually avoidable by careful tech- nique, but may relate to overdose or hypoxia, or both. Either of these situations may lead to a respiratory arrest if not addressed, and the patient will be obviously cyanosed. During any dental treatment, the vital signs should be observed, but this is par- ticularly important during sedation, when they should be formally monitored.
Management
▪ Do not give any further sedation agent.
▪ Open and maintain the airway and give oxygen.
▪ Ventilate the patient.
▪ If an overdose is suspected, consider the use of the reversal agent flumazenil (a benzodiazepine antagonist)
Emergencies arising from impaired haemostasis
It is important that any potential problems with haemosta- sis be uncovered in the medical history, so that it can be anticipated and prevented. Despite this, however, haemor- rhage may occur postoperatively in dental patients, and may be classified as primary (bleeding at the time of sur- gery) or reactionary (bleeding a few hours after surgery). Reactionary haemorrhage is often attributable to the effects of vasoconstrictor‐containing local anaesthetics wearing off. Secondary haemorrhage is that which occurs a few days after the operative procedure, and is usually attributable to infection. Further details on the management of patients with impaired haemostasis are given in Chapter 20 (titled ‘Haematology’).
SUMMARY
Medical emergencies occurring in dental practice can be alarming. A thorough history should be taken, so that possible emergencies can be anticipated to some extent. Having a good working knowledge of how to manage emergencies is mandatory for all practising clinicians.
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