Syncope — the differential and the risk stratification

The differential (the exclusion of the mimics): This is the syncope — the transient loss of consciousness with the rapid recovery and the prodrome (the warmth, the nausea, the darkened vision), from the global cerebral hypoperfusion. The seizure is excluded by the absence of the motor features, the tongue-biting, the incontinence, and the postictal confusion. The psychogenic pseudosyncope is excluded by the prodrome and the pallor (the true loss of consciousness). The hypoglycaemia is excluded by the rapid onset and the glucose. The cardiac syncope is excluded by the prodrome (the cardiac syncope is typically without the warning), the trigger (the hot environment, the prolonged standing), the young age, and the normal ECG.^[1]

The classification: the vasovagal (the reflex) syncope — the situational trigger (the hot, the crowded, the prolonged standing), the typical prodrome, the young age, the rapid recovery, and the normal examination and ECG.^[1]

The risk stratification: the low-risk patient — the reflex mechanism, the young age, the normal ECG, the no high-risk features (the no exertional, the no palpitations, the no family history of the sudden death, the no structural heart disease, the no abnormal ECG). The San Francisco and the Canadian scores confirm the low risk.^[3][4]

^[4]The discharge advice: the explanation of the benign vasovagal mechanism and the reassurance; the recognition of the prodrome and the lying down at the onset; the hydration; the avoidance of the triggers (the hot, the crowded, the prolonged standing, the rapid standing); the gradual rising from the sitting and the lying; the physical counter-pressure manoeuvres (the leg-crossing, the hand-grip); and the safety-netting to return if the syncope is recurrent, the exertional, or with chest pain or the palpitations. The driving is not restricted for the single benign vasovagal event.