Recovery from myocardial stunning is faster with desflurane compared with propofol in chronically instrumented dogs

Volatile anesthetics exert a protective role in myocardial ischemia. An inc rease in sympathetic tone might exert deleterious effects on the ischemic m yocardium. The use of the volatile anesthetic desflurane in myocardial isch emia is controversial because of its sympathetic activation. We compared pr opofol and desflurane on myocardial stunning in chronically instrumented do gs. Mongrel dogs (n = 8) were chronically instrumented for measurement of h eart rate, left atrial, aortic, and left ventricular pressure, rate of rise of left ventricular pressure, and myocardial wall-thickening fraction (WTF ). An occluder around the left anterior descending artery (LAD) allowed the induction of reversible LAD-ischemia. Two experiments were performed in a crossover fashion on separate days: 1) Induction of 10 min of LAD-ischemia during desflurane anesthesia and 2) Induction of 10 min of LAD-ischemia dur ing propofol anesthesia. Both anesthetics were discontinued immediately aft er completion of ischemia. WTF was measured at predetermined time points un til complete recovery from ischemic dysfunction occurred. Both anesthetics caused a significant decrease of WTF in the LAD-perfused myocardium. LAD-is chemia led to a further significant decrease of LAD-WTF in both groups. Dur ing the first 3 h of reperfusion, WTF was significantly larger in the desfl urane group. Mean arterial pressure and heart rate were greater during isch emia and the first 10 min of reperfusion in the desflurane group compared w ith the propofol group. Recovery from myocardial stunning in dogs was faste r when desflurane was used at the time of ischemia as compared with propofo l anesthesia. The mechanism for this difference is unclear, but sympathetic activation by desflurane was not a limiting factor for ischemic tolerance in chronically instrumented dogs.