心内直视手术灌注对冠脉血流量及ST段的影响

目的:观察分析心脏不停跳心内直视手术,灌注对冠脉血流量及ST段缺血改变的影响。方法:选择ASA I-Ⅱ级冠心病(CHD)20例,年龄(9.8±3.3)岁,体重(26.9±4.5)kg,灌注量100 ml/kg,大剂量芬太尼静脉复合麻醉,测量心肺转流插入冠状静脉管后1、5、10、15、20、25分钟的每分钟体外灌注流量,冠脉血流量,记录心电图和平均动脉压(MAP)、中心静脉压(CVP)、肛温(℃)亦同步取样观察血流酸碱气体分析及血浆电解质变化。结果:冠脉血流量在插冠管后1分钟是灌注流量的8％,5分钟后是6.6％以上。ST段在插冠管后1分钟正常,5分钟至20分钟明显上抬或下移,25分钟恢复正常。各时项MAP、CVP,肛温稳定。血液酸碱气体分析,血浆电解质正常范围,灌注流量与ST段无明显相关(P>0.05),冠脉流量与ST段有明显相关(P<0.01)。结论:体外循环心脏不停跳心内直视手术,在灌注流量稳定,冠脉血流量占灌注流量的6.5％以上。ST段缺血改变主要是手术操作,按压心脏,造成冠状动脉血流减少或局部阻塞,心肌顿时缺血所致,只要手术操作熟练完全可以避免。

The effects of cardiopulmonary bypass perfusion on coronary blood flow and ST segement during open heart surgery with beating heart.

ObjectiverTo observe the effects of cardiopulmonary bypass(CPB) perfusion on coronary blood flow and ST segement during open heart surgery with beating heart. Methods: 20 patients of ASA I - II were selected with perfusion flow 100 ml/ kg.Bypass perfusion flow and coronary blood flow per minute at 1, 5, 10, 15, 20 and 25 minutes after coronary catheterization were measured. ECG, MAP, CVP, anal temperture, blood -gas analysis and plasma electrolytes were also measured at the same time. Results: Coronary blood flow was 8% of perfusion flow at 1 minute after coronary catheterization, and above 6.6% at 5 minutes after catheterization. ST segement remained normal 1 minute after catheterization and up or down obviously at 5 to 20 minutes, back to normal at 25 minutes. MAP, CVP, anal temperature, blood - gas analysis and plasma electrolyte maintained normal during the operation.ST segement significantly relate to coronary blood flow(P<0.01), but not significantly to perfusion flow(P > 0.05) . Conclusion: Coronary blood flow is above 6. 5% of perfusion flow during open heart surgery with beating heart. The changes of ST segement mainly relate to temporary myocardial ischemia caused by pressing or pulling myocardium during operation, so we should improve our operation technique as possible.