Effect of clonidine on cardiovascular morbidity and mortality after noncardiac surgery.

Background: Perioperative myocardial ischemia occurs in 20-40% of patients at risk for cardiac morbidity and is associated with a ninefold increase in risk of cardiac morbidity.

Methods: In a prospective, double-blinded, clinical trial, we studied 190 patients with or at risk for coronary artery disease in two study groups with a 2:1 ratio (clonidine, n = 125 vs. placebo, n = 65) to test the hypothesis that prophylactic clonidine reduces the incidence of perioperative myocardial ischemia and postoperative death in patients undergoing noncardiac surgery.