Perioperative Risk Stratification in Patients Undergoing Noncardiac Surgery

Abstract

Adverse cardiac events during noncardiac surgery are a major cause of morbidity and mortality. As the population ages, greater numbers of patients (including the elderly) are undergoing noncardiac surgical procedures; additional emphasis must therefore be placed on effective preoperative risk assessment. On a national level, the estimated annual expenditure for this process is already $3.7 billion. There is a need for both the specialist and primary care provider to execute a safe, methodical, and cost efficient screening plan. This process should identify both the patients at highest risk and also those at lowest risk. Subsequently, the emphasis should attempt to minimize the overall risk of perioperative complications. The cornerstone of risk assessment requires meticulous history taking, a thorough physical examination, and usually a chest radiograph and an ECG. Five subsequent (basic) steps for the evaluation of patients for noncardiac surgery are outlined here in assessment of clinical markers and the patient's functional capacity, risk of the surgical procedure, the need for noninvasive testing, and when appropriate, the indications for invasive testing. The AHA/ACC Practice Guidelines Committee has outlined a clinical algorithm which provides a stepwise approach to guide the clinician during the decision making process. The purpose of preoperative evaluation is not to “give medical clearance” per se, but rather to evaluate the patient's current medical status, detect stress-induced ischemia in a cost effective manner, and to make recommendations about patient management throughout the entire perioperative period.