The most common cause of renal artery stenosis is atherosclerosis, the same condition that causes narrowing of the arteries in coronary heart disease and stroke, and the risk factors are the same as well. Cholesterol plaques build up along the walls of the renal artery and gradually cause narrowing.
Oxytocin is a commonly used uterotonic that can cause significant and even fatal hypotension, particularly when given as a bolus. The resulting hypotension can be produced by a decrease in systemic vascular resistance or cardiac output through a decrease in venous return.
It is not known whether having apparent erythrocytosis increases a person's thrombosis risk. Reductions in blood plasma volume, which lead to an apparent increase in red blood cells, may be caused by alcoholism, heavy smoking or the use of diuretic drugs which remove fluid from the body.