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.
Injection of oxytocin may be used to induce labor or strengthen uterine contractions during labor, to contract uterine muscle after delivery of the placenta, and to control postpartum hemorrhage. It must be administered with care to avoid trauma to the mother or infant by hyperactivity of uterine muscles during labor.