Common types of UC include: 1  proctosigmoiditis, which affects the rectum and lower portion of the colon. 2  left-sided colitis, which affects the left side of the colon beginning at the rectum.  total colitis, which affects the entire large intestine.
Vasovagal syncope. Vasovagal syncope is a sudden loss of consciousness mediated by the vagus nerve. It occurs when the vagus nerve is overreactive to certain triggers, such as the sight of blood or extreme emotional distress, and causes a sudden drop in blood pressure.
There are different syncope syndromes which fall under the umbrella of vasovagal syncope. The common element among these conditions is the central mechanism which may lead to the loss of consciousness. The differences among them are in the factors that trigger this mechanism. 1 Signs and symptoms.