Donation after cardiac death liver transplantation: Lose a bit on each one and make it up in volume

Abstract

See Article on Page 771 DBD, donation after brain death; DCD, donation after cardiac death. Liver transplant surgeons are engaged in a race to reduce waiting-list death rates, and this increasingly is requiring the expanded use of organs with a higher risk of graft failure. Declining rates of young brain-dead donors have resulted in national and international efforts to increase the donor pool, often at the expense of posttransplant outcomes. Nowhere is this more true than donation after cardiac death (DCD) liver transplantation. In multiple single-center and registry analyses, DCD liver transplantation has been demonstrated to increase the risk of graft loss from ischemic biliary injury, and retransplantation is often required.1 The impact of DCD allografts on overall patient survival remains controversial, with some centers reporting equivalent patient survival after transplantation but many demonstrating increased rates of death and retransplantation.2, 3 Although the clinical impact of DCD liver transplantation continues to be debated, it is now well established that DCD transplantation is associated with dramatically greater costs during the posttransplant period in comparison with donation after brain death (DBD) transplantation.4, 5 In this issue of Liver Transplantation, Broomhead et al.6 report a matched case series analysis comparing early posttransplant events in recipients of organs from DBD and DCD donors. They demonstrate a higher risk of perioperative events, more postoperative complications, and increases in resource utilization (including longer intensive care unit stays) among recipients of DCD organs. Among their important observations is the impact of DCD transplantation on intraoperative coagulopathy and hemodynamic instability. Compared with the DBD recipients, the DCD recipients had prolonged heparin effects (which led to increased transfusion requirements and thus increased use of expensive blood products, even though this was not a statistically significant finding), extended periods of vasopressor support, and greater evidence of allograft injury (manifested by higher serum transaminase levels). Postoperatively, the DCD patients also needed prolonged mechanical ventilator support and renal replacement therapy. Finally, the rate of graft survival at 1 year was markedly lower in the DCD liver group (75% versus 100%, P = 0.03). Despite the dire need to increase the number of organs available for transplantation, the use of DCD liver transplantation in the United States appears to have leveled off.7 Currently, 6% of liver transplants nationally use DCD organs, and this rate appears to have been unchanged for the past 4 years. There is marked regional variation in the utilization of these organs, which is driven by ongoing disparities in access to deceased donor organs. Highly competitive in access regions 1, 5, 9 continue to use the majority of the DCD organs nationally. Despite a leveling-off of the demand for DCD livers, the proportion of DCD donors in the overall donor pool increased from 2% in 2000 to 11.5% in 2009. Whether this reflects economic incentives at donor hospitals to shorten the intensive care unit length of stay and limit the opportunity for patients to progress to brain death, changes in neurosurgical or critical care treatment plans, or educational efforts and donor management by the organ procurement organizations is unclear. What is certain is that the number of donors who have progressed to brain death is diminishing. As aptly demonstrated by Broomhead et al.,6 the outcomes of DCD liver transplantation are inferior to the outcomes of DBD liver transplantation. In comparison with DBD liver transplantation, patients may survive end-stage organ failure only to have a more difficult intraoperative course and a recovery characterized by repeated intrahepatic abscesses, early graft loss, and higher utilization of costly resources. Each DCD transplant represents an unpredictable risk of long-term morbidity that might have been avoided had the donor progressed to brain death. As a result, a growing tension exists between the well-intentioned efforts of the organ donation and transplantation collaborative of the Health Resources and Services Administration to expand access to transplantation through the goal of “every organ, every time” and the day-to-day realities facing transplant centers. Unfortunately, our current reimbursement and public reporting mechanisms may be inadequate to mitigate the economic and outcome risks that DCD organs pose to transplant centers. While we are waiting for improved methods to protect organs from the deleterious impact of warm ischemic injury during the agonal period, we would be well advised to focus our attention on strategies promoting donor support to brain death if possible. Unlike business, if you lose a bit of benefit from each transplant, you cannot make it up in increased volume.