A Experimental Study for Pulmonary Transplantation from Non-heart-beating Donor.

在西方国家，肺移植已成为终末期肺部疾病患者可行的选择。虽然患者很多，但由于缺乏合适的供者，进行的肺移植数量有限。为了增加潜在供者的数量，已经进行了一些使用心脏骤停供者进行肺移植的实验研究。在日本，由于缺乏公民对脑死亡的协议，目前还没有进行脑死亡捐赠者的移植。本研究采用犬左肺移植模型，探讨了身体肺移植在临床应用的可行性。为了获得稳定的身体供体移植后的肺功能，对几项发明和改进进行了评估。(实验1)停循环后全身降温可防止供体肺热缺血损伤。我们评估了供体犬停循环…后，将供体犬浸入4℃冷水中进行全身降温的效果。更多关于移植后肺功能的信息。对比4小时全身降温和4小时室温热缺血，移植后功能无显著差异。(实验2)根据实验1的结果，我们推测这是由于停止循环后血管内形成的肺血栓所致，而大剂量的尿激酶或重组组织型纤溶酶原激活物(rt-PA)在身体肺内应用可能在保存前或保存过程中分解肺毛细血管床内的纤维蛋白，从而导致受体良好的肺功能。采用相同的犬左肺移植模型，评价应用尿激酶或rt-PA的效果。供肺灌洗前120000IU的尿激酶注射或再灌注后供肺持续输注rt-PA 5γ，均能改善移植后肺功能和血流动力学，即使是4小时的身体供肺也是如此。我们认为临床上准备肺移植的时间以4小时为宜。这些结果表明，没有理由不在日本进行身体肺移植。较少

Lung Transplantation has become a feasible option for patients with end-stage lung disease in western countries. Although ther are many patients, the number of lung transplants performed is limited, due to the lack of suitable donors. To increase the number of potential donors, some experimental studies of lung transplantation using arrested heart donors have been performed. In Japan, no transplantation from brain-dead donor is carried out yet, because of the lack of citizn agreement for brain-death. This time, we investigate the possibility of cadaver lung transplantation in clinic using canine left-lung transplantation model. And several inventions and improvements were evaluated for obtaining a stable post-transplant pulmonary functions form cadaver donor.(Experiment 1) Whole-body cooling after circulatory arrest may prevents the donor lung from warm ischemic injury. We evaluated the effect of whole-body cooling by immersing the donor canine in 4C cold water after circulatory arrest … More on the post-transplant pulmonary functions. Comparing the 4-hour whole-body cooling to 4-hour room temperature warm ischemia, there was no significant differences about post-transplant functions.(Experiment 2) From the results of experiment 1, we speculate that this was due to intra-vascular pulmonary thrombi formation after cessation of circulation, and the administration of high-dose urokinase or recombinant tissue-type plasminogen activator (rt-PA) to the cadaver lungs might decompose the fibrin inside the pulmonary capillary bed prior to or during preservation and result in superior pulmonary function in recipients. Using the same canine left lung transplantation model, the effect of administration of urokinase or rt-PA was evaluated. 120000IU of urokinase injection just prior to the donor lung flushing or 5 gamma of rt-PA continuous infusion to the recipient just after reperfusion improved the post-transplant pulmonary function and hemodynamics with even 4-hour cadaver donor lungs.We think 4-hour is enough time to prepare the lung transplantation procedure in clinic. And these results show there is no reason not to carry out cadaver lung transplantation in Japan. Less