在体体外膜肺氧合支持对心脏死亡供猪小肠的保存效果

Influence of extracorporeal membranous oxygenation on small bowel preservation in a porcine model of controlled donors after cardiac death

目的 探讨体外膜肺氧合（ECMO）技术对控制型心死亡供猪小肠的在体保存效果.方法 白色杂种猪10只,麻醉成功后颈外静脉及髂动脉置管连接ECMO系统,待供猪心死亡后启动ECMO,建立再循环灌洗腹腔器官.分别于供猪术前、心死亡、ECMO支持1、3、5h时获取小肠组织,评估各时间点小肠黏膜组织病理、电镜、能量代谢以及细胞凋亡水平.结果 ECMO支持可快速恢复供猪小肠组织的血液供应,部分恢复供肠黏膜组织的ATP含量.ECMO支持1h时,小肠黏膜组织病理评分以及细胞凋亡水平与术前的差异无统计学意义（P＞0.05）;随着ECMO支持时间的延长,小肠黏膜损伤程度逐渐加重,小肠黏膜ATP含量也随之降低.结论 ECMO支持1h可改善心死亡供猪小肠的活力,小肠上皮细胞Caspase-3的大量活化可能是ECMO支持引起供猪小肠黏膜受损的机制之一.

Objective To evaluate the effect of extracorporeal membranous oxygenation （ECMO） on the small bowel preservation in a porcine model of controlled donors after cardiac death （CDCD）.Method The domestic crossbred donor pigs were anesthetized and ventilated with 100% oxyger.An intravenous cannula was placed through iliac arteries and jugular vein,and connected to ECMO system.The ECMO was performed to infuse abdominal organs when cardiac death was declared.Pathology,electron microscope,energy metabolism and cell apoptosis level of intestinal mucosa were evaluated before operation,in cardiac death and at the end of extracorporeal support,respectively.Result The normothermic extracorporeal support could quickly restore graft blood supply and oxygenation.One-h extracorporeal support could improve the energy status in intestine of donation after cardiac death （DCD）.The histologic damage and apoptosis of 1-h extracorporeal support had no significant difference with those before operation and in cardiac death （P〉0.05）.With the extension of extracorporeal support,the intestinal mucosa damage degree was gradually increased,and the content of adenosine triphosphate in intestinal mucosa reduced gradually.Conclusion The normothermic extracorporeal support for 1 h in DCD is beneficial for improving the viability of small bowel.However,the integrity of intestinal mucosa is destroyed gradually as extracorporeal supporting time over,which may be initiated by the activation of intestinal epithelial apoptosis.