Transient loss of consciousness from global cerebral hypoperfusion with rapid spontaneous recovery.
Etiology
- • Reflex (vasovagal, situational, carotid sinus)
- • Orthostatic (volume loss, drugs, autonomic failure)
- • Cardiac (arrhythmia, structural)
History taking
- • Prodrome, posture, triggers, witness account
- • Tongue bite, incontinence (favour seizure)
- • Family history sudden death
Examination
- • Lying & standing BP, cardiac murmur
- • Carotid bruit, neurological screen
Red flags
- • Syncope on exertion / supine
- • Family history sudden cardiac death
- • Abnormal ECG
Differential diagnosis
- • See differentials section per chief complaint
Recommended investigations
- • 12-lead ECG (all)
- • FBC, U&E, glucose
- • Echo / Holter / tilt-table per suspicion
Diagnosis
- • Clinical diagnosis supported by targeted investigations
Initial treatment / management
- • Treat underlying cause
- • Symptomatic relief
- • Patient education
Follow-up advice
- • Review in 2–4 weeks or earlier if worsening
- • Monitor response to therapy and adverse effects
Patient counselling
- • Explain diagnosis and natural course in lay terms
- • Red-flag symptoms warranting urgent return
- • Adherence to medications and follow-up
Referral criteria
- • Refer if diagnostic uncertainty, complications, or failure of first-line therapy
Clinical pearls
- • Use San Francisco Syncope Rule or CHESS to triage
References
- • Harrison's Principles of Internal Medicine, 21e
- • NICE / WHO guidelines (current edition)
Educational outpatient guide — verify against local guidelines before clinical use.
