Myocardial protection by volatile anesthetics in patients undergoing cardiac surgery: A critical review of the laboratory and clinical evidence

摘要

JOHN BLAND AND EDWARD LOWENSTEIN first reported in 1976 that administration of halothane (0.75 minimum alveolar concentration [MAC]) significantly (p < 0.001) attenuates ST-segment elevation caused by brief coronary artery occlusion in 6 dogs anesthetized with chloralose-urethane concomitant with a reduction in the primary determinants of myocardial oxygen consumption. These experiments demonstrated, for the first time, that volatile anesthetics are capable of producing essential anti-ischemic effects. Since the publication of this landmark paper, several studies provided further evidence that volatile anesthetics protected myocardium against reversible and irreversible ischemic injury. For example, isoflurane and halothane enhanced the functional recovery of postischemic-reperfused ("stunned") canine myocardium when either volatile anesthetic was administered before a 15-min coronary artery occlusion and reperfusion. This beneficial effect occurred in conjunction with the preservation of high-energy phosphates. Isoflurane also reduced the magnitude of myocardial necrosis and improved recovery of left ventricular (LV) function after global ischemia and reperfusion.