Vasovagal syncope (fainting)

Description Fainting caused by ...

Description

Fainting caused by a vasovagal reaction. A vasovagal reaction is the most common cause of fainting. It is an over stimulus of the parasympathetic nervous system by such triggers as the sight of blood or extreme emotional distress. The response causes a slowing of the heart rate and a drop in the blood pressure resulting in decreased blood flow to the brain and a loss of consciousness. It is the reason people faint when they hear bad news or have their blood drawn.

Symptoms

Sudden nausea, lightheadedness and fainting after seeing blood or an emotional event. Other symptoms include: sweating, vomiting.

Tests

Common tests used for diagnosis and treatment

Workup:
A history and physical exam will be performed. Tests may be done to rule out other causes of the fainting.

Tests:
Complete blood count (CBC), Comprehensive metabolic panel (CMP), CT Scan, D-Dimer, Electrocardiogram (EKG), Troponin, Urinalysis (UA), X-ray

Do I need this test?
In the evaluation of simple syncope and a normal neurological examination, don't obtain brain imaging studies (CT or MRI). In patients with witnessed syncope but with no suggestion of seizure and no report of other neurologic symptoms or signs, the likelihood of a central nervous system (CNS) cause of the event is extremely low and patient outcomes are not improved with brain imaging studies.


Specialists:
Internal Medicine, Pediatrics, Family Practice

Treatment

The main therapy is avoidance of the trigger. Immediately sitting down or laying down at the first warning of the event may prevent the fainting.