Critical questions in syncope: Risk stratification in the Emergency Department

• Objective: To review the management of syncope, with a focus on evaluation, diagnosis, and risk stratification in the emergency department (ED). • Methods: Review of the literature and authoritative guidelines. • Results: Syncope is a transient loss of consciousness due to transient global cerebral hypoperfusion characterized by rapid onset, short duration, and spontaneous complete recovery. A prolonged post-ictal phase is the best discriminator between a true syncopal event with an anoxic seizure and a likely neurological seizure. Sudden onset syncope without pre-warning symptoms may be indicative of syncope of cardiac origin and must be taken seriously. Initial ED evaluation with a detailed history, complete physical examination, and 12-lead ECG will suggest the cause of syncope in about 40% of patients. For these patients, management should focus on treating the underlying condition. For unstable patients in whom a diagnosis is unclear, the focus should be on resuscitation and further investigation. For stable patients in whom there is no obvious underlying cause, risk stratification should be done to assess whether the patient is at high risk of a serious cardiovascular event or death. • Conclusion: In patients with syncope, it is important for the clinician to take a detailed history, perform a focused examination, and be aware of the potential pitfalls that may lead to failure to recognize a potentially fatal condition.