摘要目的 应用微量透析技术评估心脏死亡猪供肝的热缺血损伤程度,并筛选出相关指标.方法 以猪为实验对象,建立心脏死亡模型并对肝脏进行不同时间热缺血操作,利用微量透析技术监测能量代谢指标(葡萄糖、乳酸、丙酮酸、甘油及乳酸/丙酮酸比值)在不同热缺血时间点的变化,同时评估各热缺血时间点供肝组织病理学变化.结果 随着热缺血时间的延长,肝组织病理损伤进行性加重.葡萄糖、丙酮酸水平热缺血早期轻度下降,随热缺血时间延长而升高;甘油水平随热缺血时间延长,逐渐升高;乳酸水平在热缺血20 min后明显升高;乳酸与丙酮酸比值在热缺血20 min后明显升高.乳酸水平以及乳酸/丙酮酸比值随热缺血时间的延长而增高.乳酸水平及乳酸/丙酮酸比值与肝缺血时间(即肝病理损伤程度)呈明显的正相关性(P＜0.001,P＜0.001,相关系数分别为0.682和0.453).以热缺血30min作为供肝不可用,乳酸的ROC曲线下面积为0.950,丙酮酸的曲线下面积为0.885.以热缺血30 min作为供肝不可用,乳酸水平以及乳酸/丙酮酸比值均可作为判断供肝是否可用的指标(P＜0.001,P＜0.001),乳酸的曲线下面积为0.950,丙酮酸的曲线下面积为0.885;当乳酸阈值选取2.3736时,其敏感性达90％,特异性达95％.当乳酸/丙酮酸比值阈值选取0.0257时,其敏感性达80％,特异性达83％.结论 乳酸水平及乳酸/丙酮酸比值与肝缺血时间呈明显的正相关性,可以作为热缺血损伤的检测指标.

abstractsObjective To analyze the relative indicators associated with warm ischemia time (WIT).Methods We established the porcine donor after cardiac death (DCD) model and monitored biochemical parameters (glucose,lactate,pyruvate,glycerol,and glutamate) changes of porcine livers at different WIT by microdialysis technique.The pathological changes were also observed during different WIT by HE staining.Results As the extension of WIT,the morphology injury of the graft aggravated:glucose and pyruvate levels slightly declined in the early stage,and then increased with WIT entension;glycerol levels increased with WIT entension;lactate levels and lactate/pyruvate ratio increased significantly after 20 min of WIT.The expression of lactate and lactate/pyruvate ratio were increased with the prolonged WIT.Pearson correlation analysis of all factors with liver ischemia time and liver pathological injury degree (P＜0.05) showed the obvious correlation between lactate,lactate/pyruvic acid ratio with liver ischemia time and liver pathological injury degree,and of positive correlation (P＜0.001,and correlation coefficients were 0.682 and 0.453 respectively).The ROC curve analysis revealed that the area under the curve was 0.950 for lactate,and 0.885 for pyruvate,respectively.When the critical value of lactic acid was 2.3736,the sensitivity was 90％ and specificity was 95％.When the critical value of lactate/pyruvate ratio was 0.0257,the sensitivity was 80％ and specificity was 83％.Conclusion The level of lactic acid and lactate/pyruvate ratio are significantly related to the WIT.These factors may be used as a predictor of donor liver warm ischemia injury.Reference range of these indicators needs further discussion based on larger sample research.