Syncope – Emergencies
Medical Emergencies
Syncope
Syncope (fainting) occurs due to decreased cerebral blood flow resulting in a sudden and brief loss of consciousness and postural tone. If prolonged, may result in seizure and cerebral ischemia.
Causes and types of syncope
- peripheral vascular or circulatory compromise
- vasopressive (often associated with pain and/or stress, gagging, and coughing (posttussive))
- hypovolemia (orthostatic hypotension)
- recreational drugs or medications
- carotid sinus syndrome
- autonomic dysfunction
- central nervous system – cerebrovascular (including stroke and transient ischemic attacks), seizure, emotional
- metabolic – hypoglycemia, anemia, hypoxia, hypercapnea
- cardiac – obstructive (including thrombotic and embolic events), arrhythmias
Signs and symptoms
Early:
- nausea
- warmth
- perspiration
- loss of color
- drop in blood pressure
- increased pulse (tachycardia)
- change in sensorium
Late:
- hypotension
- decreased pulse (bradycardia)
- increased breathing pattern (hyperpnea)
- pupillary dilation
- peripheral coldness
- visual disturbance
- seizure activity
- loss of consciousness
Differential diagnosis
- anxiety attack
- hypoglycemia
- hypotension
- hyperventilation
- myocardial infarction
- seizure
Action
- place the patient in the Trendelenburg position (the body is laid flat on the back (supine position) with the feet higher than the head) or left lateral decubitus (on the left side, place a rolled towel under the right hip) for a pregnant women
- assess consciousness
- assess Circulation (blood pressure, heart rate), Airway, Breathing
- administer oxygen, 6-8 L/min by nasal cannula or mask
- use spirits of ammonia
- monitor blood pressure, pulse, and respiratory rate
- place a cold towel on the patient’s forehead
- if patient is persistently bradycardic (pulse rate <60 beats/minute), administer atropine 0.5mg IV or 1mg IM every 5 minutes until max dose of 3 mg
- alert emergency medical services (EMS) if loss of consciousness continuous for >5 minutes, or if recovery time is >20 minutes
- arrange for home escort
- notify patient’s primary care provider
- call later to check on patient
Related Pages
- Medical Disorders
- Classifications and Definitions
References/Websites
- References
- Greenwood M, et al. General medicine and surgery for dental practitioners: part 2. Medical emergencies in dental practice: the drug box, equipment and basic principles of management. BDJ. 2014;216(11):633-637.
- Greenwood M. General medicine and surgery for dental practitioners: part 3. Management of specific medical emergencies in dental practice. BDJ. 2014;217(1):21-26.
- Haas DA. Preparing dental office staff members for emergencies. Developing a basic action plan JADA. 2010;141(5 suppl):8S-13S.
- Jevon P. Medical emergencies in the dental practice poster: revised and updated. BDJ. 2020;229(2):97-104.
- Rosenberg M. Preparing for medical emergencies. The essential drugs and equipment for the dental office. JADA. 2010;141(5 suppl):14S-19S.
- Runser LA, et al. Syncope: evaluation and differential diagnosis. Am Fam Physician. 2017;95(1):303-312.
- Websites