Précis:

Preparation for, and basic management of, medical emergencies occurring in the dental surgery are discussed. Prompt recognition and management can result in a successful outcome.

Abstract:
Statement of the problem: Medical emergencies can and do happen in the dental surgery. In the 20- to 30-year practice lifetime of the typical dentist, he/she will encounter between five and seven emergency situations. Being prepared in advance of the emergency increases the likelihood of a successful outcome.
Purpose of the paper: To prepare members of the dental office staff to be able to promptly recognise and efficiently manage those medical emergency situations that can occur in the dental office environment.
Materials and methods: Preparation of the dental office to promptly recognise and efficiently manage medical emergencies is predicated on successful implementation of the following four steps: basic life support for ALL members of the dental office staff; creation of a dental office emergency team; activation of emergency medical services (EMS) when indicated; and, basic emergency drugs and equipment. The basic emergency algorithm (P→C→A→B→D) is designed for implementation in all emergency situations.
Results and conclusions: Prompt implementation of the basic emergency management protocol can significantly increase the likelihood of a successful result when medical emergencies occur in the dental office environment.

StanleyMalamed

Stanley F. Malamed DDS
Dentist Anesthesiologist, Emeritus Professor of Anesthesia & Medicine

Herman Ostrow School of Dentistry of USC, Los Angeles, California, USA
E: malamed@usc.edu

Introduction
Medical Emergencies Table 1

Medical Emergencies Table 2

Life-threatening emergencies can and do happen in the practise of dentistry. They can happen to anyone – a patient, dentist, member of the office staff, or a person merely accompanying a patient. Though the vast majority of medical emergencies occur in patients during treatment, a significant number develop in non-patients. In a combined survey of 4,309 North American dentists a total of 30,608 emergencies were reported (Table 1).1,2 A total of 11% occurred in non-patients. Some 20% of 84 medical emergencies reported in an American dental school between 2000 and 2008 occurred in non-patients.3 Between 1973 and June 2012, 34.4% of 282 medical emergencies occurring in the University of Southern California School of Dentistry occurred in non-patients.4
Dentistry is stressful. Patients attend dental surgeries with many pre-existing fears, including fear of experiencing pain, fear of the local anaesthetic injection, fear of being injured by the drill, fear of gagging, and other fears too numerous to mention. These fears commonly manifest themselves as medical emergencies when the patient attempts to keep their fear internalised – to ‘tough it out’, to ‘take it like a man’.
Matsuura, reporting on medical emergencies in Japanese dental offices, found that 54.9% of the emergencies occurred during local anaesthetic administration, while 22% occurred during the ensuing dental treatment.5 The most common treatments being received at the time the medical emergency arose were tooth extraction (38.9%) and pulpal extirpation (26.9%).
Emergencies such as syncope (fainting), hyperventilation, the acute ‘epinephrine (adrenalin) reaction’, acute angina pectoris, acute pulmonary oedema, acute asthmatic episodes, stroke and seizures are frequently precipitated in the dental environment by fear that goes unnoticed and unmanaged by the dentist. We term these emergencies ‘stress related’. Other emergencies, including allergy, hypoglycaemia, local anaesthetic overdose (toxic reaction) and postural hypotension are non stress-related. Myocardial infarction (heart attack) and cardiac arrest may be either stress- or non stress-related.
Atherton et al. reported 1,380 emergencies occurring among 701 dentists in England and Wales, and 760 emergencies arising among 328 Scottish dentists.6 Wilson et al. reported that among Irish dentists, excluding syncope, adverse medical events occur at a rate of 0.7 cases per dentist per year (Table 2).7 A more recent report (2012) found 793 reported incidents among 300 British dentists.8,9
Deaths have also been reported in the dental office environment. Atherton et al. reported 13 dental office deaths over a 10-year period.6 Interestingly, 11 of the 13 deaths occurred in the waiting room prior to the start of dental treatment. The procedures undergone by the two patients who died in the dental surgery were ‘dentures’ and ‘scaling’.6
During his 40-year tenure as a full-time professor at the University of Southern California School of Dentistry, the author encountered one cardiac arrest death – in a patient having his full dentures relined.

Preparation
The dental office staff must be prepared to promptly recognise and effectively manage those medical emergencies that arise. Proper training of all staff, and the immediate availability of essential items of equipment and emergency drugs, are essential for a successful outcome to result. The four steps in preparation are: basic life support training; office emergency team; access to emergency medical services (EMS); and, emergency drugs and equipment.

Basic life support training
Basic life support (BLS, CPR [cardiopulmonary resuscitation]) training for all members of the office staff represents THE most important step in preparation. The ability to recognise and manage an unconscious person is paramount to their survival. The basic algorithm – P→C→A→B→D – is discussed below. All office personnel should be required by the dentist to receive this training annually. BLS training should be carried out in the dental office if possible, as this is where the emergencies will happen.
Office emergency team
Develop a plan before an emergency happens. A simple emergency team is described below:
Member #1 is the first person at the scene of the emergency. When the emergency arises in the dental chair this might be the dentist, hygienist or assistant. Where the situation occurs in the reception area it is the reception staff who will respond first, hence the recommendation that all office personnel be BLS-HCP trained. Member #1: remains with the patient; administers BLS, as needed; and, activates the dental office emergency team (e.g., calls for help).
Member #2 is assigned to immediately bring the emergency equipment to the site of the emergency. The oxygen cylinder, emergency drug kit and automated external defibrillator (AED) should be kept together in an easily accessible location (e.g., near a telephone).
Member #3 is, in fact, the remaining members of the office staff. Possible duties include: activation of EMS; waiting outside the office for arrival of the EMS and escorting them to the office; ‘holding’ the lift in the reception area for the EMS; monitoring vital signs; preparing emergency drugs for administration; keeping a written record of the event, including a time line and treatment (e.g., 10.15am – EMS called; 10.21 – EMS arrives in dental office); and, assisting in BLS.
The dentist remains the team leader, the person legally responsible for the health and safety of the patient. Tasks may be delegated as long as the person performing the task is capable of doing it well under the dentist’s supervision.
Table 3 summarises the duties of each member of the dental office emergency team.

 

Medical Emergencies Table 3

Emergency medical services
There are two questions to consider: when to call?; and, whom to call?

When to call for assistance: Emergency medical assistance should be sought as soon as the dentist (the person legally responsible for the health and safety of the patient) feels it is needed. This occurs: 1. if the diagnosis of the problem remains unknown; 2. when the diagnosis is known but is disturbing to the dentist; and, 3. at any time the dentist feels uncomfortable and wishes to seek help. Never hesitate to seek assistance in managing a medical emergency if you feel it is warranted.
Whom to call: Emergency medical services (EMS) are the first responders to life-threatening medical emergencies in most areas. Throughout Ireland, 999 is the EMS number. A second emergency number (112 – the European Union EMS number) may be called within Ireland as well (Figure 1). Response times vary significantly from community to community. In almost all situations, EMS arrival occurs within ten minutes. Where response time is prolonged (e.g., traffic or rural environment) and the dental office is located in a ‘medical–dental’ complex, there might be another healthcare professional well trained in emergency management available.
On arrival at the site of the emergency, the EMS will take over management. Primary duties of the EMS are to: keep the patient alive; stabilise the patient’s condition at the scene; and, transport the patient to the emergency department of a hospital for definitive care, if needed.

Emergency drugs and equipment

MedicalEmergencies-Fig1-2

FIGURE 1 (left): Irish emergency medical services telephone numbers. FIGURE 2 (right): ‘D’ (M-15) and
‘E’ (M-24) oxygen cylinders.

Medical Emergencies Figure 3

FIGURE 3: Pocket mask.

Medical Emergencies Figure 4

FIGURE 4: Self-inflating bag-valve-mask device.

Every dental office requires a set of basic emergency drugs and equipment. The Quality and Patient Safety Committee of the Irish Dental Association has developed an excellent Audit Tool on Emergency Drugs and Equipment that provides the dentist with a suggested list of drugs and equipment in the form of a checklist (Table 4).10 Interestingly, this author (an American) has recommended these same basic emergency drugs – with subtle differences in form – for all dental offices since 1999 in his emergency medicine textbooks.11-13
Injectable drugs: The basic kit includes two injectable drugs: epinephrine (adrenalin) either 1:1,000 (for patients >30kg in weight) or 1:2,000 (up to 30kg weight); and, an antihistamine. Both drugs are used in the management of allergic reactions. The histamine-blocker is used to treat non-life-threatening allergy (e.g., itching, hives, rash), whereas the immediate administration of epinephrine – the most important drug in emergency medicine in this author’s opinion – is essential in the life-threatening allergic reaction anaphylaxis. Epinephrine should be available in a preloaded autoinjector (e.g., Epipen, Anapen). The importance of epinephrine in the management of anaphylaxis is illustrated by the fact that survival is unlikely without its administration.14

Non-injectable drugs: Five non-injectable drugs are recommended: glucose for management of hypoglycaemia (low blood sugar); glyceryl trinitrate (nitroglycerin) for management of an acute episode of angina pectoris; a salbutamol inhaler for management of acute asthma; aspirin, in a powdered or chewable form, for administration in management of first-time chest pain or a suspected myocardial infarction; and, oxygen (O2), minimally in a “D” cylinder, preferably an ‘E’ cylinder (Figure 2), as well as the appropriate equipment for its delivery.
Emergency equipment: There are several important items of emergency equipment related to airway management.

  1. Pocket mask, for mouth-to-mask ventilation (Figure 3). It is suggested that each member of the dental office staff have their own pocket mask, and be trained to use it during the next CPR training course taken by the office. The ability to use a pocket mask to maintain airway patency and ventilate an apnoeic unconscious patient is one of the most important steps in saving a life. Mouth-to-mask ventilation provides the patient with approximately 16% oxygen.
  2. A self-inflating bag-valve-mask device (Figure 4) enables ventilation of the patient with ambient enriched O2 levels (~20.9%) or with enriched O2 (21% to ~90%).
  3. A spacer device for a bronchodilator. These are used primarily in paediatric asthmatics; a spacer allows for a greater volume of bronchodilator to enter the lungs (Figure 5).
  4. Plastic, disposable syringes with needles, for injectable drug administration. It is suggested that the emergency kit have four 2ml syringes with needles.
  5. An automated external defibrillator (AED) (Figure 6). This author has advocated the availability of AEDs in dental offices for the past 25 years.15,16 Survival (to hospital discharge) from out-of-hospital sudden cardiac arrest is intimately related to the time elapsed from collapse of the patient to defibrillation. In the absence of CPR being delivered prior to EMS arrival, defibrillation is delayed, with resultant survival rates decreasing at approximately 7-10% per minute.17 With bystander-initiated CPR, survival rates diminish more slowly, at a rate of between 3% and 4% per minute (Table 5).17

 

FIGURE 5

FIGURE 5: Spacer device for bronchodilator.

FIGURE 6. Automated external defibrillator.

FIGURE 6. Automated external defibrillator.

 

 

 

Medical Emergencies Table 4

Medical Emergencies- Table 5

Basic management of medical emergencies
Although it is hoped that life-threatening medical emergencies will not occur in the dental surgery, it is a fact that they do happen. Management of all medical emergencies adheres to the same basic algorithm: P→C→A→B→D where P is positioning, C is circulation, A is airway, B is breathing, and D is definitive care.18
The initial management of ALL medical emergencies is the same: P→C→A→B→D. These constitute the steps of basic life support (CPR) and are designed to ensure that the patient’s brain receives an adequate supply of blood (containing the oxygen and glucose necessary to sustain life). Once these steps have been implemented – as needed – D, definitive care, is considered. Definitive care may be further divided as follows: Diagnosis; Drugs; and, Defibrillation.

P = Positioning

Medical Emergencies Figure 7

FIGURE 7: Supine position recommended for all unconscious persons.

The very first step in the management of all medical emergencies is to properly position the patient. As our goal in managing emergencies is to keep the patient alive, the ability to deliver oxygenated blood to the brain is of paramount importance.
If the patient is conscious the position of choice is whatever position is most comfortable for them. By definition, a conscious person responds appropriately to verbal or physical stimulation.19 For the patient to be able to respond appropriately there must exist an adequate blood supply to the patient’s brain. Any position the patient finds comfortable is therefore appropriate in this situation. Examples include the asthmatic during an acute episode of bronchospasm and the person experiencing chest pain. Lying recumbent in the dental chair, the asthmatic becomes acutely short of breath at the onset of bronchospasm. It is a virtual guarantee that they will sit upright at the onset of the episode as they are able to ‘breathe better’ (both psychologically and physiologically) in this more upright position. Persons experiencing chest ‘pain’ (e.g., angina pectoris, myocardial infarction) will also, in most instances, assume an upright position. If a conscious patient wishes to lie down there is no contraindication to their doing so.
With the loss of consciousness (LOC), it becomes imperative to place the patient into the supine position with their feet elevated slightly. The rationale behind this is the fact that by far the most common aetiology of LOC in humans is a decrease in the flow of blood to the brain. This may result from a drop in blood pressure (hypotension) or decrease in heart rate (bradycardia), or both. Deprived of an adequate blood supply, the brain – deprived of both oxygen and glucose – can no longer function normally and consciousness is lost.
In the supine position the patient’s back is placed parallel to the floor so that the heart and brain are at the same level (Figure 7). On the contemporary dental chair the feet of the patient will be slightly elevated, allowing gravity to force the significant volume of blood in the patient’s legs back to their chest and thence to the brain.
It is not recommended that an unconscious patient be positioned such that their head is lower than their heart. Termed the Trendelenburg position (named after the German surgeon Friedrich Trendelenburg), this position significantly increases blood flow to the brain but, at the same time, impairs the patient’s ability to breathe effectively by forcing the abdominal organs (stomach, intestines, liver, spleen) up into the diaphragm, the major muscle of respiration.

Positioning summary
Conscious – any position the patient finds is comfortable.
Unconscious – supine with feet elevated slightly.

C = Circulation

Medical Emergencies Figure 8

FIGURE 8: Location of the carotid pulse.

The second step is to confirm that there is an adequate flow of blood to the patient’s brain. To do so the carotid pulse is checked (Figure 8).
In a conscious patient there is no need to physically check for the carotid pulse. Consciousness implies that there is at least an adequate flow of oxygenated blood to the brain.
With LOC, the ability of the rescuer to quickly and accurately locate the carotid pulse becomes critical. It should be palpated for not more than 10 seconds, using the index and middle fingers (not the thumb, as it contains a rather large artery of its own). If the pulse is present the rescuer proceeds to the next step (airway assessment). If, in this 10-second time frame, the carotid pulse is absent or if there is any doubt as to its presence, chest compression is started immediately.

Circulation summary
Conscious – no need to palpate for carotid pulse.
Unconscious – check carotid pulse for not more than 10 seconds. If pulse is not present, or if there is any doubt, initiate chest compressions using a compression/ventilation ratio of 30 compressions to two ventilations. The compressions should be delivered at a rate of at least 100 per minute.

A = Airway

Medical Emergencies Figure 9

FIGURE 9: Head tilt – chin lift procedure for managing airway in unconscious persons.

Having ensured that the patient’s brain is receiving an adequate supply of blood (P’C) we next determine if the blood is well oxygenated.
In the conscious patient who can speak there is no need to physically assess airway patency and breathing (subsequent step = B), as speech can only occur when the patient: 1. is conscious; 2. has a patent airway; and 3. is breathing.
However, in the unconscious patient airway patency must be assessed. The untrained rescuer will provide hands-only (compression-only) CPR, e.g., compressions without ventilations.20 However, healthcare providers (e.g., dentists, physicians) should provide a patent airway using the “head tilt – chin lift” manoeuvre (Figure 9). This author considers this simple procedure to be the most important step in the management of an unconscious person. A properly performed head tilt – chin lift will effectively provide a patent airway in virtually all instances of unconsciousness.21

Airway summary
Conscious and speaking – airway is patent. No need for airway management.
Unconscious – head tilt – chin lift should be performed.

B = Breathing
The 2010 AHA (American Heart Association) Guidelines for CPR and ECC de-emphasised checking for breathing. Healthcare providers as well as lay rescuers may be unable to accurately determine the presence or absence of adequate or normal breathing in unresponsive patients,22,23 because the airway is not open24 or because the patient has occasional gasps, which can occur in the first minutes after sudden cardiac arrest, and may be confused with adequate breathing. Termed ‘agonal breaths’, they do not necessarily result in adequate ventilation. The rescuer should treat the patient who has occasional gasps as if he or she is not breathing.
In the absence of spontaneous breathing or ineffective breaths the rescuer must deliver rescue breaths. Healthcare providers should deliver ventilations at a regular rate of one breath every six to eight seconds (8-10 breaths/minute). Each breath should be of one second’s duration and a volume sufficient to produce visible chest rise delivered.25 All members of the dental office team should be trained in the use of a face mask and/or bag-valve-mask device (Figures 3 and 4).

Breathing summary
Conscious and speaking – no need to assess.
Unconscious – assess for effective breathing; if not breathing or if breaths are ineffective, initiate rescue breathing.

D = Definitive care
The steps employed thus far, P→C→A→B→D are keeping the patient alive by ensuring that their brain is receiving oxygenated blood. In the dental environment, the reality is that the vast majority of emergency situations will require only ‘P’ – positioning, followed by ‘D’ – definitive care. When consciousness is lost proper positioning is all that is required for the patient to recover consciousness. ‘C’ will be evaluated and noted to be present, ‘A’ (head tilt – chin lift) will be required if the patient does not recover consciousness promptly, and ‘B’ will seldom be necessary.
Definitive care may be subdivided into three other ‘D’ categories: diagnosis; drugs; and, defibrillation. If a diagnosis can be made, then subsequent management is usually straightforward (management of specific emergency situations is the subject of the second article in this series).
Several of the more common medical emergencies seen in dentistry require the administration of drugs. Examples include nitroglycerin for acute anginal discomfort, an inhaled bronchodilator for acute asthmatic episodes, aspirin for a suspected myocardial infarction, and glucose for management of hypoglycaemia. Oxygen may be administered to patients of almost all emergencies. Of the two injectable drugs, chlorpheniramine (IV antihistamine) will be used in the management of allergic reactions and epinephrine is administered in the (happily extremely rare in dentistry) anaphylactic reaction. Timely defibrillation is critical to survival in instances of cardiac arrest.17

Summary
Medical emergencies can – and do – happen in the practice of dentistry. The entire dental office staff should be trained to: prevent these situations from arising through the recognition and management of the patient’s fears, and the use of effective pain control during treatment; and, be prepared to recognise and effectively manage those emergencies that might still arise. Preparation includes: basic life support training, on an annual basis, for all members of the office staff; development of a dental office ‘emergency team’, where members have assigned tasks and all members are interchangeable; calling emergency medical services (999 or 112) when the situation warrants it; having available a basic emergency drug kit and items of equipment; and, being able to effectively manage the emergency situation until the patient either recovers or help arrives on the scene and takes over management of the situation.

References

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  2. Malamed, S.F. Managing medical emergencies. J Am Dent Assoc 1993; 124: 40-53.
  3. Anders, P.L., Comeau, R.L., Hatton, M., Neiders, M.E. The nature and frequency of medical emergencies among patients in a dental school setting. J Dent Educ 2010; 74: 392-396.
  4. Malamed, S.F. Handbook of Medical Emergencies (7th ed.). CV Mosby, St. Louis: 2015: 2.
  5. Matsuura, H. Analysis of systemic complications and deaths during treatment in Japan. Anesth Prog 1990; 36: 219-228.
  6. Atherton, G.J., McCaul, J.A., Williams, S.A. Medical emergencies in general dental practice in Great Britain. Part 1: their prevalence over a 10-year period. Br Dent J 1999; 186: 72-79.
  7. Wilson, M.H., McArdle, N.S., Fitzpatrick, J.J., Stassen, L.F.A. Medical emergencies in the dental practice. J Irish Dent Assoc 2009; 55 (3): 134-143.
  8. Jevon, P. Updated guidance on medical emergencies and resuscitation in the dental practice. Br Dent J 2012; 212: 41-43.
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  10. Quality and Patient Safety Committee. Audit Tool on Emergency Drugs and Equipment. Irish Dental Association 2013; volume 1, pages 1-3.
  11. Malamed, S.F. Handbook of Medical Emergencies in the Dental Office (5th ed.). CV Mosby, St. Louis: 2000: 65.
  12. Malamed, S.F. Handbook of Medical Emergencies in the Dental Office (6th ed.). CV Mosby, St. Louis: 2007: 70.
  13. Malamed, S.F. Handbook of Medical Emergencies in the Dental Office (7th ed.). CV Mosby, St. Louis: 2015: 74.
  14. O’Keefe, A. ‘Emma Sloan, 14, dies of nut allergy in Dublin after pharmacist refuses to hand over injection without prescription’. Irish Herald, December 20, 2013 – www.herald.ie.
  15. Malamed, S.F. Automated external defibrillators: part 1: Introduction and rationale. Dent Today 2003; 22 (6): 106-109, 111.
  16. Malamed, S.F. Automated external defibrillators: part 2: Application. Dent Today 2003; 22 (7): 52-55.
  17. The Public Access Defibrillation Trial Investigators. Public-access defibrillation and survival after out-of-hospital cardiac arrest. N Engl J Med 2004; 351: 637-646.
  18. Field, J.M., Hazinski, M.F., Sayre, M.R., Chameides, L., Schexnayder, S.M., et al. Part 1: executive summary: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation 2010; 122 (Suppl. 3): S640-S656.
  19. American Society of Anesthesiologists Task Force on Sedation and Analgesia by Non-Anesthesiologists. Practice guidelines for sedation and analgesia by non-anesthesiologists. Anesthesiology 2002; 96: 1004-1017.
  20. Travers, A.H., Rea, T.D., Bobrow, B.J., Edelson, D.P., Berg, R.A., et al. Part 4: CPR overview: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation 2010; 122 (Suppl. 3): S676-S684.
  21. Guildner, C.W. Resuscitation: opening the airway. A comparative study of techniques for opening an airway obstructed by the tongue. JACEP 1976; 5: 588-590.
  22. Bahr, J., Klingler, H., Panzer, W., Rode, H., Kettler, D. Skills of lay people in checking the carotid pulse. Resuscitation 1997; 35: 23-26.
  23. Ruppert, M., Reith, M.W., Widmann, J.H., Lackner, C.K., Kerkmann, R, et al. Checking for breathing: evaluation of the diagnostic capability of emergency medical services personnel, physicians, medical students, and medical laypersons. Ann Emerg Med 1999; 34: 720-729.
  24. Safar, P., Escarraga, L.A., Chang, F. Upper airway obstruction in the unconscious patient. J Appl Physiol 1959; 14: 760-764.
  25. Baskett, P., Nolan, J., Parr, M. Tidal volumes which are perceived to be adequate for resuscitation. Resuscitation 1996; 31: 231-234.

Acknowledgement
The author would like to thank Dr Sheila Galvin BDenTSc MFD MB MRCPI, Specialist Registrar in Oral Medicine, Dublin Dental University, for her assistance in preparing this manuscript.