Certainly we’ve all taken care of of the patient with the chief complaint “possible seizure.” Upon history and examination many of us will discover that the patient had syncope. So, the purpose of this post is to examine how we differentiate between convulsions in a epileptic seizure versus those that occur when a patient faints. Read on!
What actually happens when a patient faints?
There is a brief loss of consciousness that is associated with transient global cerebral hypoxia. The most common causes of syncope in the pediatric population are:
- Vasovagal (neurocardiogenic): 50% of cases that present to the ED. Often precipitated by prolonged standing and physical or emotional stress. Most patients experience the typical prodrome, which includes lightheadedness, dizziness, pallor, diaphoresis, nausea and visual changes. The reflexes that govern heart rate and vasomotor tone are exaggerated, and a drop in BP leads to global cerebral hypoperfusion.
- Breath-holding spells: Seen in toddlers and triggered by emotional stress (tantrum) or minor painful stimuli. They can lead to loss of consciousness and brief posturing or tonic-clonic convulsions. Read here for more.
- Orthostatic hypotension: This is syncope that occurs with postural changes (prolonged standing, just standing up upon being supine for a prolonged period of time). An abrupt drop in BP may result from dehydration, pregnancy (venous pooling in the lower extremities), anemia, anorexia nervosa and certain medications (diuretics and other BP meds).
Other causes for fainting include: