Estimation of cardiac risk before noncardiac surgery: the evolution of cardiac risk indices.
ABSTRACT Postoperative cardiac complications are among the most feared events in patients undergoing noncardiac surgery. Hospitalists, internists, cardiologists, and anesthesiologists are frequently asked to provide preoperative consultations to assess risk and optimize medical treatment for the patient. Over the years, numerous studies have attempted to define preoperative risk factors in an attempt to risk stratify patients and determine when interventions may be applied to reduce risk. These studies have proposed various risk indices and algorithms based on identification of different risk factors, related to variations in patient populations, types of surgery, definitions of comorbidities, and endpoints studied. This article reviews many of these risk indices, highlighting their findings, utilities, and limitations.