Myocardial ischemia following surgery: preliminary findings. Study of Perioperative Ischemia (SPI) Research Group

Abstract

Humoral changes, changes in hemodynamics, and the incidence of ischemia appear to be highest during the postbypass-postoperative period. Preliminary data also suggest that postbypass ischemia detected by transesophageal echocardiography may be predictive of outcome. Our previous experience with postoperative hypertension following coronary artery surgery has led us to increase analgesic medication of patients during and following anesthetic emergence. Patterns of postoperative ischemia observed in patients undergoing noncardiac and cardiac surgery suggest that extension of anesthesia to the postoperative period may be beneficial with respect to suppression of ischemia. It appears that by maintaining a continuous infusion of a high dose of narcotic, postoperative myocardial ischemia can be modified. The implication is that by blunting activation of the sympathetic nervous system in the postoperative period, and preventing the resultant endocrine, metabolic, and hemodynamic changes, the imbalance of myocardial oxygen supply and demand can be shifted away from ischemia. Further investigation is needed to confirm these data, and to address the effects of modification of postoperative myocardial ischemia on eventual postoperative cardiac outcomes.