Syncope

 

Syncope is one of the most common problems encountered in the emergency department. The greatest challenge is determining who should be admitted for inpatient investigations and who can be investigated as an outpatient. 

1) What is it: Transient, self limited, loss of consciousness.

2) How is it classified:

 3) Approach to Diagnosis:

• The cause of a syncopal event is often in the HISTORY
• The history should focus on the following:
• Circumstances surrounding episode: Position (supine, sitting, upright); activity (micturition, defecation, unpleasant experience, exertion); predisposing factors (warm, crowded etc.)
• Prodromal symptoms: Nausea, vomitting, diaphoresis, aura, palpitations or lack of prodorome
• Eye witnesses: Abnormal posturing, movements of limbs, incontinence etc.
• After the event: New weakness, confusion, level of consciousness
• History: Previous events, family hx of sudden cardiac death, hx of coronary artery disease, structural heart disease.
•  Historical features worrisome for cardiac syncope:
• Lack of prodromal symptoms, syncope with exertion or supine. Syncope associated with palpitations.
• Hx of structural cardiac disease
• Abnormal ECG (sinus bradycardia, Mobitz II or 3rd degree, intraventricular conduction delay (QRS >0.12sec)
•  Boston Syncope Criteria: Patients meeting any one of the following criteria should be admitted for further investigation:
• Signs and symptoms of ACS
• Worrisome cardiac history (hx of CAD, CHF, hx VT/Vfib, pacemaker/ICD, antiarrhythmic medications)
• Family hx of sudden death
• Valvular heart disease on hx of exam
• Signs of conduction disease
• Volume depletion
• Perisistent abnormal vital signs in the ED
• Primary CNS event.

4) Investigations:

•  Cardiac investigations:
• Telemetry
• ECHO
• Exercise test
• Ischemia evaluation
• If the above is normal, consider the following tests as an outpatient: 
• If symptoms are frequent Holter monitor 24-48hr
• If symptoms are infrequent consider Implantable loop recorder
• Tilt table testing if hx suggestive of neurocardiogenic syncope

See the following for more information:
Boston Syncope Criteria
European Heart Journal guidelines on treatment of syncope