浅低温心脏不停搏心内直视手术对心肌保护作用的临床研究

目的 探讨浅低温心脏不停搏心内直视手术对心肌的保护作用。方法 采用静脉复合麻醉，全身肝素化，常规插管，在浅低温心脏不停搏及低温心脏停搏状态下分别行房间隔缺损或室间隔缺损修补术各20例，观察2组患者术中体外循环时间，最低鼻咽温度，术后4各时间点收缩压（SBP），舒张压（DBP），心率（HR），中心静脉压（CVP），体温（T）以及术后呼吸机支持时间，心包，纵隔引流量等。结果 不停搏组体外循环时间较停搏组明显缩短，转流期间最低灌注压和最低鼻咽温度明显高于停搏组；不停搏组术后血流动力学稳定，而停搏组入室后2h时SBP较入室时显著降低（P＜0．05），且术后升压药物使用例数，输血例数及心率失常发生例数均较不停搏组多；入室24h时停搏组体温较不停搏组升高（P＜0．05），术后呼吸机支持时间较不停搏组明显延长（P＜0．05）。结论 浅低温不停搏心脏手术有很好的心肌保护作用。

The clinical study of the effects of beating heart and mild hypothermia on myocardium protection during cardiopulmonary bypass

Objective To study the effect of beating heart and mild hypothermia on the myocardium protection during cardiopulmonary bypass (CPB).?Methods 40 patients with atrial septal defect or ventricular septal defect were randomly divided into two groups: beating heart under mild hypothermia group (Group 1, n =20) and cold cardioplegic arrested heart group (Group 2, n =20). All patients were under general anesthesia and heparinization. CPB was established in them. The length of CPB and the lowest nasopharyngeal temperature during CPB were noted. The postoperative conditions were studied by measuring a host of physiological parameters at intervals within 48 h.?Results The length of CPB was evidently shorter in Group 1 than in Group 2; the lowest nasopharyngeal temperature and the lowest perfusion pressure were higher in Group 1. Postoperatively, the hemodynamics was relatively stable in Group1. Whereas in Group 2, the systolic BP dropped significantly within 2 h after entering the ICU ( P <0.05), the frequencies of postoperative use of pressor drugs, blood transfusion and remedies for cardiac arrhythmia were all higher in Group 2. The patients' body temperature was higher ( P <0.05) and the time of respiratory support required was longer ( P <0.05) in Group 2. The amount of pericardial and mediastinal drainage was less in Group1 than in Group 2.?Conclusion Satisfactory protection of the myocardium can be achieved by practicing the surgery on beating heart under mild hypothermia.