Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM); Department of Surgery, Faculty of Medicine, Université de Montréal.
Division of Cardiac Surgery, Dalhousie University.
J Vis Exp. 2022 May 10(183). doi: 10.3791/64009.
The increase in demand for cardiac transplantation throughout the years has fueled interest in donation after circulatory death (DCD) to expand the organ donor pool. However, the DCD process is associated with the risk of cardiac tissue injury due to the inevitable period of warm ischemia. Normothermic regional perfusion (NRP) allows for an in situ organ assessment, allowing the procurement of hearts determined to be viable. Here, we describe a clinically relevant large-animal model of DCD followed by NRP. Circulatory death is established in anesthetized pigs by stopping mechanical ventilation. After a preset warm ischemia period, an extracorporeal membrane oxygenator (ECMO) is used for a NRP period lasting at least 30 min. During this reperfusion period, the model allows the collection of various myocardial biopsies and blood samples for initial cardiac evaluation. Once NRP is weaned, biochemical, hemodynamic, and echocardiographic assessments of cardiac function and metabolism can be performed before organ procurement. This protocol closely simulates the clinical scenario previously described for DCD and NRP in heart transplantation and has the potential to facilitate studies aimed at decreasing ischemia-reperfusion injury and enhance cardiac functional preservation and recovery.
多年来，对心脏移植的需求不断增加，这促使人们对死后循环（DCD）捐赠产生了兴趣，以扩大器官捐献者库。然而，DCD 过程会增加心脏组织损伤的风险，因为不可避免地会出现温热缺血期。常温区域灌注（NRP）可进行原位器官评估，从而获取可存活的心脏。在这里，我们描述了一个临床相关的大动物 DCD 后 NRP 模型。通过停止机械通气，在麻醉猪中建立循环死亡。在预设的温热缺血期后，使用体外膜肺氧合（ECMO）进行至少 30 分钟的 NRP 期。在此再灌注期间，该模型允许收集各种心肌活检和血液样本，以进行初始心脏评估。一旦停止 NRP，就可以在器官采集前进行心脏功能和代谢的生化、血流动力学和超声心动图评估。该方案密切模拟了先前在心脏移植中描述的 DCD 和 NRP 的临床情况，有可能促进旨在减少缺血再灌注损伤和增强心脏功能保存和恢复的研究。
