常温氧合血性心停搏液持续灌注心肌保护效应的实验研究

目的　采用随机对比的实验研究方法从测定心肌酶学、氧自由基代谢产物及心肌特异性蛋白几个方面来探讨冷晶体心停搏液间断灌注及常温氧合血性心停搏液连续灌注两种灌注方法的心肌保护效应。方法１４只犬随机分为①对照组：冷晶体心停搏液间断灌注；②实验组：常温氧合血性心停搏液连续灌注。采集不同时点的犬冠状静脉窦血为测定标本，测定心肌特异性酶ＣＫ－ＭＢ、心肌特异性钙蛋白Ｔ（ｃＴｎ－Ｔ），氧自由基代谢产物丙二醛（ＭＤＡ）。结果对照组在主动脉开放后，ＣＫ－ＭＢ、ＭＤＡ、ｃＴｎ－Ｔ明显升高，实验组升高幅度较小。两组间比较有显著差异（Ｐ＜０．０１）。结论常温氧合血性心停搏液连续灌注，可以充分保证心肌在常温停跳期间的血供和氧供，避免了心肌缺血缺氧，明显地减轻了心肌缺血再灌注损伤，是一种非缺血性、比较理想的心肌保护方法。

Experimental Study on Myocardial Protection with Continuous Warm Blood Cardioplegia

Objective :To compare effects of myocardial protection in dogs randomised to intermittent cold crystalloid cardioplegia or continous normothermic blood Cardioplegia. Methods 14 dogs randomised to ① control gioup: intermittent cold crystalloid cardioplegia perfusion; ②experimental group: continuous normothermic blood cardioplegia perfusion. Blood samples were taken from the coronary sinus just before cross clamp application, end cross clamp and at intervals up to 15min after cross clamp release. Myocardial ischaemia reperfusion injury was assessed by the difference in plasma concentrations of CK-MB, MDA, cardiactroponin T(cTn-T), respectively. Results intermittent cold crystalloid cardioplegia resulted in a significant increase in CK-MB, MDA, cTn-T; no significant corresponding changes were present with continuous blood cardioplegia. The diference between the two groups was significant(p<0.01). Conclusion Intermittent cold cardioplegia resulted in severe myocardial ischaemic reperfusion injury due to the hypothermic, a myocardial ischemic period. Continuous blood cardiople gia was enough to maintain myocardial normal metalism, to preserve and increase energy supply in cardiac arrest, to abollish myocardial ischemic period and to avoid myocardial ischemic reperfusion injury. Continuous blood cardioplegia is an ideal protective method for non-ischemic myocardia.