Con: All elective coronary artery bypass grafting patients are not American Society of anesthesiologists' physical status IV

Abstract

T HE AMERICAN SOCIETY OF ANESTHESIOLOGISTS (ASA) developed the ASA Physical Status Classification in the early 1960s (Table 1). ~ The purpose of the physical status classification was to standardize the extent of disease in patients presenting for surgery and to promote a common language among different institutions for subsequent examination of anesthetic morbidity and mortality. 2 The intent was that the physical status classification should be independent of the proposed surgery. Thus, a patient with end-organ manifestations of diabetes mellitus may be an ASA Physical Status III regardless of whether the proposed surgery is a hernia repair or a femoral-popliteal bypass. Predictably, anesthetic morbidity and mortality in large groups of patients with a variety of comorbid diseases have consistently correlated well with perioperative morbidity and mortality. However, factors other than the physical status have been used to define risk of surgery with improved positive predictive value. Some are algorithms or point-scoring systems that try to identify perioperative cardiac risk for such adverse outcomes as myocardial infarction (MI), congestive heart failure, or death. 3-5 Coronary artery disease (CAD) is the most common cause of death in the United States. 6 It is prevalent in large numbers of patients, and its prevalence will only increase as the proportion of elderly patients in the population continues to grow. The prevalence of CAD in the population is challenged only by that of hypertension. Unfortunately, hypertension often is more silent than CAD, and as many as 50% of the millions of patients with hypertension in the United States remain untreated. 7 The mortality from acute MI, however, has seen a dramatic decline in the past decade, a decrease of approximately 3% per year. 8 The leading reasons for this decrease include control of hypercholesterolemia, aggressive medical treatment of CAD, intensive care of the patient with an acute MI, and modest changes in the pattern of cigarette abuse. Thus, although MI is still the leading cause of sudden death in the United States, the feeling of gloom and doom surrounding this event is slowly being replaced by a sense of optimism, especially if the patient with acute myocardial ischemia has early access to hospital care. The optimistic outlook for the patient with MI has prompted the rethinking of the risk of elective surgery after MI. The data reported by Tarhan et al9 in 1972 and by Rao et al 1° in 1983 were the basis for recommendations to delay elective surgery for several months after acute MI. The current recommendation of the American College of Cardiology (ACC) and the American Heart Association (AHA) is to assess the functional status of patients as early as 4 weeks after MI and to proceed with