A 78-year-old man with a history of coronary aery disease and an asymptomatic reducible inguinal hernia requests an elective hernia repair. Which of the following would be a valid reason for delaying the proposed surgery?
High-Yield Explanation
The work of Goldman and others has served to identify risk factors for perioperative myocardial infarction. The highest likelihood is associated with recent myocardial infarction: the more recent the event, the higher the risk up to 6 months. It should be noted, however, that the risk never returns to normal. A non-Q-wave infarction may not have destroyed much myocardium, but it leaves the surrounding area with borderline perfusion, thus the paicularly high risk of subsequent perioperative infarction. Evidence of congestive hea failure, such as jugular venous distention, or S3 gallop also carries a high risk, as does the frequent occurrence of ectopic beats. Old age (>70 years) and emergency surgery are risk factors independent of these others. Coronary revascularization by coronary aery bypass graft (CABG) tends to protect against myocardial infarction. Smoking, diabetes, hypeension, and hyperlipidemia (all of which predispose to coronary aery disease) are surprisingly not independent risk factors, although they may increase the death rate should an infarct occur. The value of this information and data derived from fuher testing is that it identifies the patient who needs to be monitored invasively with a systemic aerial catheter and pulmonary aerial catheter. Most perioperative infarcts occur postoperatively when the third-space fluids return to the circulation, which increases the preload and the myocardial oxygen consumption. This generally occurs around the third postoperative day.