Perioperative cardiac risk reduction: doing it right.

Abstract

arious interventions to reduce the risk of cardiac complications during surgery have been proposed. This article evaluates the evidence for these preventive approaches, examines methods of incorporating new and conflicting evidence into a coherent clinical approach, and reviews systems for successfully implementing evidence-based interventions in the hospital. ■ APPROACHES FOR PREVENTING CARDIAC COMPLICATIONS With revascularization reserved as a preventive measure for those patients at extremely high risk of cardiac complications, other less invasive preventive approaches should be considered. Maintenance of normothermia One preventive approach is maintenance of normal body temperature. In a randomized, controlled clinical study of 300 patients with or at high risk for coronary disease who underwent major abdominal or vascular surgery, supplemental warming care was associated with a significant (P = .02) reduction in perioperative morbid cardiac events compared with routine thermal care. 1 The risk of supplemental warming is low and the potential reward is high; in addition to the reduction in cardiac complications, patients randomized to normothermia in this study had a lower rate of surgicalsite infections, less nausea, and better pain control. Calcium channel blocker therapy A recent meta-analysis 2 demonstrated a significant reduction in adverse coronary endpoints with the use of calcium channel blockers, compared with placebo, as preventive therapy in patients undergoing various types of surgery. This reduction in the risk of events, however, was driven entirely by a significant reduction in the incidences of ischemia and supraventricular tachycardia, with no effect of calcium channel blockers on perioperative myocardial infarction (MI) or death. The largest reductions in risk with calcium channel blockers occurred in patients undergoing thoracic surgery. In most of the studies in which a favorable effect of calcium channel blockers was observed, patients were on concomitant beta-blockade that was not adequately controlled for, which obscures interpretation of the meta-analysis. For these reasons, calcium channel blockers should not be considered firstline therapy as a preventive strategy.