Share your insights

Help us by sharing what content you've recieved in your exams


Vasovagal syncope

Definition
  • A transient loss of consciousness caused by a temporary drop in blood flow to the brain, often due to a reflex of the involuntary nervous system.
Etiology/Triggers
  • Emotional distress: fear, severe pain, distressing sights.
  • Standing for long periods.
  • Heat exposure.
  • Physical factors: coughing, urination, swallowing.
  • After exercise.
Pathophysiology
  • Overreaction of the parasympathetic nervous system (vagus nerve) leading to bradycardia (slow heart rate) and vasodilation (widening of the blood vessels).
  • Results in reduced cardiac output and transient cerebral hypoperfusion.
Clinical Presentation
  • Prodromal symptoms: lightheadedness, nausea, feeling warm, pallor, visual “blackout”, sweating.
  • Transient loss of consciousness (often less than a minute).
  • Recovery is typically rapid but may be associated with transient confusion.
Investigations
  • Clinical history: Most diagnostic.
  • ECG: To rule out cardiac causes.
  • Orthostatic blood pressure measurements.
  • Tilt table test: Diagnostic in some cases.
  • Holter monitor: If episodic or suspicion of arrhythmia.
Management
  • Educate about triggers and early warning signs.
  • Counterpressure manoeuvres: leg crossing, handgrip, arm tensing.
  • Increased salt and fluid intake.
  • Avoid prolonged standing, especially in hot environments.
  • Gradual physical training.
  • Pharmacological: beta-blockers, fludrocortisone, SSRIs ā€“ used in recurrent cases.
Prognosis
  • Generally benign but has the potential for injury due to falls.
  • Recurrent episodes are common.

No comments yet šŸ˜‰

Leave a Reply