What is syncope?

Syncope is a temporary loss of consciousness caused by a fall in blood pressure (hypotension) with insufficient blood flow to the brain. This loss of consciousness is often called fainting or ‘passing out’ or ‘blacking out’. Syncope can be benign, or it can be a symptom of an underlying problem. In either case, syncope should be treated as a medical emergency.

What causes syncope?

As mentioned above, syncope is caused by the loss of blood pressure and blood flow to the brain. This loss of blood flow into the brain can reduce the flow of blood, oxygen or glucose to key areas of the brain. Underlying causes for this loss of blood flow can include the heart failing to pump the blood to the brain, blood vessels that fail to hold pressure and deliver blood to the brain, loss of blood, carbon monoxide poisoning or any combination of these. Syncope is not caused by head trauma. Head trauma is its own cause of loss of consciousness, known as a concussion.

Fainting is actually the body trying to survive this loss of blood flow to the brain, as the brain shuts down non-vital functions in order to conserve blood and oxygen for vital organs. Additionally, heart rate may increase in order to get more blood to the brain.

Syncope is common to about 20% of children and young adults.

Curious as to how to pronounce syncope?

Syncope is pronounced, SING-kuh-pee. Listen here.

How to treat syncope

Given the multiple causes of syncope, there is not one single treatment for syncope.  Treatments range from simple relaxation to installation of a pacemaker or a catheter to medicines.