Rolf N, Meissner A, Van Aken H, Weber T P, Hammel D, Möllhoff T
Department of Anesthesiology, University Hospital Munster, Germany.
Anesth Analg. 1997 Apr;84(4):723-9. doi: 10.1097/00000539-199704000-00004.
The purpose of this investigation was to examine the effects of thoracic epidural anesthesia (TEA) on myocardial stunning during propofol anesthesia. Six dogs were chronically instrumented for measurement of left atrial, aortic, and left ventricular pressure, maximal rate of increase of left ventricular pressure, and myocardial wall-thickening fraction (WTF). Myocardial blood flow was determined with colored microspheres. Experiments were performed on separate days with 1) 10 min of left anterior descending artery (LAD) ischemia during propofol anesthesia without TEA, and 2) 10 min of LAD ischemia during propofol anesthesia with TEA. WTF was measured as baseline (BL) prior to propofol anesthesia and at predetermined time points until complete recovery from stunning. Propofol anesthesia caused a significant decrease of WTF in the LAD-perfused myocardium (LAD-WTF) compared to BL in awake animals. LAD ischemia led to a further significant decrease of LAD-WTF. There were no significant differences in LAD-WTF between the two experimental conditions at any of the time points measured. TEA did not change subendocardial blood flow in nonischemic myocardium. During ischemia neither the subendocardial/subepicardial nor the occluded/normal zone blood flow ratio were affected by TEA. After myocardial ischemia during propofol anesthesia TEA does not affect functional recovery of stunned myocardium in dogs.
本研究的目的是探讨胸段硬膜外麻醉（TEA）对丙泊酚麻醉期间心肌顿抑的影响。对6只犬进行长期仪器植入，以测量左心房、主动脉和左心室压力、左心室压力最大上升速率以及心肌增厚分数（WTF）。用彩色微球测定心肌血流量。在不同日期进行实验，1）丙泊酚麻醉且无TEA时左前降支动脉（LAD）缺血10分钟，2）丙泊酚麻醉且有TEA时LAD缺血10分钟。在丙泊酚麻醉前及直至从顿抑完全恢复的预定时间点测量WTF作为基线（BL）。与清醒动物的BL相比，丙泊酚麻醉导致LAD灌注心肌（LAD-WTF）中的WTF显著降低。LAD缺血导致LAD-WTF进一步显著降低。在任何测量时间点，两种实验条件下的LAD-WTF均无显著差异。TEA未改变非缺血心肌的内膜下血流量。缺血期间，TEA既不影响内膜下/心外膜血流量比值，也不影响闭塞/正常区域血流量比值。丙泊酚麻醉期间心肌缺血后，TEA不影响犬顿抑心肌的功能恢复。
