Fainting (Syncope)

Syncope/Simple fainting

Common.
Overstimulation of heart by vagus nerve, decreasing rate of cardiac contraction  drop in cardiac outflow  compensated by peripheral vasoconstriction to increase blood flow to brain (vasovagal response). The sudden fall in blood pressure  sudden brief loss of consciousness  full recovery in several minutes

Cause – some sort of stimulus – eg pain; grief; anxiety; fear; emotional events; standing for long periods; sight of blood or needles.

Clinical features:
Prodrome  dizziness/light headed; yawning; nausea; pale, cold, clammy skin; may feel hot; anxious; dimming of vision; tachycardia
Then  collapse; loss of consciousness; bradycardia; may have abnormal movements

Management:
If unconscious  place in lateral stable position; raise legs if possible
If conscious  lie flat; raise legs if possible
If heat syncope  loosen clothing and cool by fanning
May recur if stand up within 30 minutes