The preoperative period summary.

Cardiac risk stratification for noncardiac surgery has evolved through medical technologic and economic revolutions over the past 22 years. Prior to 1977, physicians had only the anesthesia classes 1 to 5 to advise their patients and families of the risks of anesthesia and surgery. This clinical index was subjective and did not predict cardiac morbidity well.1 Goldman et al2 developed the first validated model to predict cardiac complications in a general surgical population. A cardiac risk index for cardiac death and life-threatening complications of myocardial infarction, pulmonary edema, and ventricular tachycardia was defined for patients in four risk classes. Patients with angina were excluded from this early study. As thallium scintigraphy became widespread and IV dipyridamole became available, Boucher et al3 defined a 30% risk of perioperative ischemic events in patients with redistribution on thallium scans. This launched hundreds of studies and articles to define preoperatively the risk of general anesthesia and surgery in patients with coronary heart disease (CHD). The original cardiac risk index of Goldman et al2 was modified by Detsky et al4 in 1986 to include angina pectoris, remote myocardial infarction, congestive heart failure, aortic stenosis, and emergency surgery. A simplified scoring system and three classes of risk were validated on patients undergoing vascular and nonvascular surgery. Combining clinical criteria and thallium scan results in patients undergoing major vascular surgery, Eagle et al5 found five clinical predictors for cardiac complications. An age . 70 years, angina pectoris, diabetes mellitus, Q waves on ECG, and premature ventricular contractions on ECG were found to be predictive of cardiac complications. If the patient had one predictor, there was a 3% risk of cardiac complications. If there were two or three predictors, there was a 3 to 15% risk, which increased to a 30% risk if reperfusion was present on thallium scans. If there were four or five predictors, the risk was . 15% and further preoperative cardiac studies were indicated. From a practical and economic standpoint, these criteria are still used by many clinicians performing preoperative evaluations. Thallium perfusion scans were utilized extensively until 1991 when Mangano et al6 found that the scan results were not always predictive of ischemic events. The development of stress echocardiography and dobutamine stress echocardiography provided a more convenient and less expensive risk stratification procedure. Poldermans et al7 defined the benefits of dobutamine stress echocardiography for assessment of perioperative cardiac risk in patients undergoing major vascular surgery. The use of atropine to reach target heart rates in patients undergoing dobutamine stress echocardiograms increased the sensitivity and specificity of this test.8 Because of the enormous medical-legal and economic implications of perioperative risk management in patients with CHD, clinical practice guidelines were published by the American College of Cardiology, American Heart Association, and the American College of Physicians.9,10 In response to the membership of the American College of Chest Physicians, this supplement addresses the preoperative risk assessment, the intraoperative management of cardiac and pulmonary monitoring, fluids, and blood transfusions, and the postoperative management of pain, ventilation, nutrition, and renal insufficiency. Special topics of elderly patients and cancer patients are addressed. Evidence-based tables are presented when the literature can provide this analysis.