Anesthesia and Medical Emergencies in Dentistry
This domain tests whether you can prevent, recognise and treat the emergencies that actually occur in a dental chair, and whether you know the correct drug, route and dose under pressure.
Prevention
- Take a medical history and assign an ASA class; check blood pressure, anticoagulant status and glycaemic control. Simple extractions are generally acceptable at an INR below 3.5, with attention to timing of direct oral anticoagulants.
- Position patients appropriately: supine with legs elevated for syncope, semi-supine for breathless or pregnant patients.
Recognition and response
- Vasovagal syncope is the most common emergency: pallor, sweating, bradycardia and hypotension. Lay the patient supine, raise the legs, give oxygen and monitor.
- Local anaesthetic overdose shows early excitation, tachycardia, a metallic taste and agitation, then convulsions and central depression.
- Anaphylaxis presents with urticaria, bronchospasm and hypotension; give adrenaline 0.01 mg per kg intramuscularly of the 1:1000 solution, maximum 0.5 mg, repeated every five minutes.
- Hypoglycaemia needs oral or intravenous glucose; angina needs sublingual nitrate; asthma needs a salbutamol inhaler; a seizure requires protection from injury, not restraint; cardiac arrest requires 30:2 compressions and an AED.
Preparedness
An emergency kit with oxygen, suction, an AED, adrenaline, glyceryl trinitrate, salbutamol, glucose and an antihistamine, plus regular team drills, is the standard.
Worked example
A 30-year-old becomes pale, sweaty and bradycardic two minutes after an inferior alveolar nerve block. Vasovagal syncope is the likely diagnosis: reposition supine with legs raised, give oxygen, monitor and reassure. Local anaesthetic overdose would present with tachycardia, agitation and a metallic taste, and anaphylaxis with urticaria or wheeze.
Traps
- Giving intramuscular adrenaline for a simple faint.
- Seating a syncopal patient upright.
- Advising aspirin in an asthmatic.
- Failing to call for help early.