Extracorporeal Support of the Non-Heart-Beating Organ Donor

As in many transplant centers, concern over the ever-increasing numbers of recipients waiting for transplantation has prompted us to initiate a non-heart-beating (NHB) organ donor program, primarily to provide more donor kidneys but also to potentially enhance our liver procurement rates. Although NHB organ donors have been used by some transplant programs for many years (1–4), there has been considerable hesitancy in pursuing this option for organ donation (5). Working with the well-established extracorporeal membrane oxygenation (ECMO) program in our medical center, we have designed a protocol to resuscitate the donor after formal declaration of cardiac death, enabling a rapid return to near normal hemodynamics and oxygen delivery to the vital organs. With the use of normothermic whole-body ECMO, we believe that this method of resuscitating NHB organ donors will enable not only improved renal transplant outcomes, but also potentially allow procurement of livers, pancreata, and perhaps thoracic organs with excellent allograft function. Potential donors who are candidates for ECMO-assisted NHB organ donation are controlled NHB donors (Maastricht III) in whom irreversible brain injury has occurred. This protocol was approved by the University of Michigan Ethics Committee. After the donor has been medically cleared, consent is obtained for NHB donation by non-transplant staff. Femoral cannulas are placed percutaneously in both artery and vein. Shortly after cannula placement, the patient is taken off all vasopressors and extubated. A period of time, not to exceed 1 hr, is allowed to elapse during which the potential organ donor succumbs to cardiopulmonary arrest. Asystole is verified for 5 min, after which the patient is pronounced dead by the primary service. The patient is then fully heparinized and ECMO support started. The patient's family is then given a final opportunity to stay with the donor in the intensive care unit, after which the patient is brought to the operating room for procurement surgery. During this time the donor is kept stable and hemodynamics are monitored. At the appropriate time, the cooling unit of the ECMO circuit is started and kept at 4°C, while University of Wisconsin solution is instilled under gravity and blood recirculation is discontinued. Once the kidneys have been removed, they are placed on a perfusion pump for evaluation. Kidneys procured from two ECMO-supported NHB organ donations showed normal perfusion characteristics. Two of the four procured kidneys were transplanted without delayed graft function and show normal function. The remaining two organs were not transplanted because of positive serologies. Clinical characteristics from these NHB organ procurements are shown in Table 1. Of particular importance is the similar hemodynamics of the patients during ECMO compared with before declaration of death. Although the SvO2 was suboptimal during cardiopulmonary demise, it quickly returned to normal during extracorporeal support.Table 1In summary, we believe that normothermic whole body ECMO-supported NHB organ donation offers significant advantages over previously described methods, including decreased warm ischemia time with rapid resuscitation and attainment of normal hemodynamics after cardiopulmonary death; relative ease of methodology; the capability to procure extrarenal organs; and improved family acceptance. Although further experience with this methodology is needed, our initial results are encouraging and warrant further study. Steven M. Rudich Juan D. Arenas John C. Magee Mark T. Gravel Richard H. Chenault II Liise K. Kayler Robert M. Merion Jeffrey D. Punch