Association Between Organ Procurement Organization Social Network Centrality and Kidney Discard and Transplant Outcomes.

BACKGROUND: Given growth in kidney transplant waitlists and discard rates, donor kidney acceptance is an important problem. We used network analysis to examine whether organ procurement organization (OPO) network centrality affects discard and outcomes. METHODS: We identified 106,160 deceased donor kidneys recovered for transplant from 2000 to 2010 in Scientific Registry of Transplant Recipients. We constructed the transplant network by year with each OPO representing a node and each kidney-sharing relationship between OPOs representing a directed tie between nodes. Primary exposures were the number of different OPOs to which an OPO has given a kidney or from which an OPO has received a kidney in year preceding procurement year. Primary outcomes were discard, cold-ischemia time, delayed graft function, and 1-year graft loss. We used multivariable regression, restricting analysis to the 50% of OPOs with highest discard and stratifying remaining OPOs by kidney volume. Models controlled for kidney donor risk index, waitlist time, and kidney pumping. RESULTS: An increase in one additional OPO to which a kidney was given by a procuring OPO in a year was associated with 1.4% lower likelihood of discard for a given kidney (odds ratio, 0.986; 95% confidence interval, 0.974-0.998) among OPOs procuring high kidney volume, but 2% higher likelihood of discard (odds ratio, 1.021; 95% confidence interval, 1.006-1.037) among OPOs procuring low kidney volume, with mixed associations with recipient outcomes. CONCLUSIONS: Our study highlights the value of network analysis in revealing how broader kidney sharing is associated with levels of organ acceptance. We conclude interventions to promote broader inter-OPO sharing could be developed to reduce discard for a subset of OPOs.

Preimplant histologic acute tubular necrosis and allograft outcomes.

BACKGROUND AND OBJECTIVES: The influence of deceased-donor AKI on post-transplant outcomes is poorly understood. The few published studies about deceased-donor preimplant biopsy have reported conflicting results regarding associations between AKI and recipient outcomes. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This multicenter study aimed to evaluate associations between deceased-donor biopsy reports of acute tubular necrosis (ATN) and delayed graft function (DGF), and secondarily for death-censored graft failure, first adjusting for the kidney donor risk index and then stratifying by donation after cardiac death (DCD) status. RESULTS: Between March 2010 and April 2012, 651 kidneys (369 donors, 4 organ procurement organizations) were biopsied and subsequently transplanted, with ATN reported in 110 (17%). There were 262 recipients (40%) who experienced DGF and 38 (6%) who experienced graft failure. DGF occurred in 45% of kidneys with reported ATN compared with 39% without ATN (P=0.31) resulting in a relative risk (RR) of 1.13 (95% confidence interval [95% CI], 0.9 to 1.43) and a kidney donor risk index-adjusted RR of 1.11 (95% CI, 0.88 to 1.41). There was no significant difference in graft failure for kidneys with versus without ATN (8% versus 5%). In stratified analyses, the adjusted RR for DGF with ATN was 0.97 (95% CI, 0.7 to 1.34) for non-DCD kidneys and 1.59 (95% CI, 1.23 to 2.06) for DCD kidneys (P=0.02 for the interaction between ATN and DCD on the development of DGF). CONCLUSIONS: Despite a modest association with DGF for DCD kidneys, this study reveals no significant associations overall between preimplant biopsy-reported ATN and the outcomes of DGF or graft failure. The potential benefit of more rigorous ATN reporting is unclear, but these findings provide little evidence to suggest that current ATN reports are useful for predicting graft outcomes or deciding to accept or reject allograft offers.

Longer-term outcomes after kidney transplantation from seronegative deceased donors at increased risk for blood-borne viral infection.

BACKGROUND: Transmission of human immunodeficiency virus and hepatitis C to transplant recipients has drawn attention of the use of allografts from seronegative donors at increased risk for blood-borne viral infection (DIRVI). METHODS: We performed a cohort study of 7803 kidney transplant recipients whose kidneys were recovered through one of two organ procurement organizations from 1996 to 2007. Detailed organ procurement organization data on donor risk factors were linked to recipient data from the Organ Procurement and Transplantation Network. RESULTS: Median recipient follow-up was 3.9 years. Three hundred sixty-eight (5%) patients received DIRVI kidneys, a third of which were procured from donors with a history of injection drug use or commercial sex work. Compared with standard criteria kidney recipients, DIRVI kidney recipients were more likely to be human immunodeficiency virus positive or black. In multivariable Cox regression, using DIRVI recipients as the reference, recipients of standard criteria donor kidneys had lower mortality (hazard ratio [HR] 0.71, P<0.01) and no difference in death-censored allograft failure (HR 1.09, P=0.62), whereas recipients of expanded criteria donor kidneys had no significant difference in mortality (HR 0.98, P=0.83) but a higher allograft failure rate (HR 1.93, P<0.01). High-quality data on posttransplant recipient viral testing were not available. CONCLUSIONS: DIRVI kidney recipients experienced higher mortality than standard criteria kidney recipients. This finding could be explained if sicker patients received DIRVI kidneys (i.e., residual confounding) or the less likely possibility of undetected transmission of viral infections. Given the limitations of registry data used in this analysis, prospective studies are needed to further elucidate these findings.

The development of a successful multiregional kidney paired donation program.

BACKGROUND: Kidney paired donation (KPD) is increasing the number of living donor transplants. Two major obstacles prevent moving KPD forward in the United States: (1) achieving a critical mass of pairs to efficiently find matches and (2) efficiently coordinating KPD transplants between multiple transplant centers. Two large regional programs, The New England Program for Kidney Exchange (NEPKE) and the Mid-Atlantic Paired Exchange Program (MAPEP) have developed a system of protocols to effectively increase the number of KPD transplants. METHODS: Incompatible pairs and nondirected donors (NDD) are referred to the system through transplant centers. Donor and recipient ABO, human leukocyte antigen, and recipient human leukocyte antigen antibody screening are used to determine potential matches. Utilization of a computer optimization algorithm matches pairs in two- and three-way exchanges, NDD chains, and list exchange chains. Team conference calls regarding transfer of information, crossmatches, surgery date, coordination of simultaneous donor nephrectomies, and other issues are coordinated as needed. RESULTS: Ten matches moved forward to donation and transplantation, and one is pending. Eight of these matches involved NDD chains, two 2-way exchanges, and 1 a list exchange chain. These matches resulted in 27 transplants. Eighteen transplants occurred in NEPKE-only transplant centers, four in MAPEP-only centers, and an additional five were crossregional. CONCLUSION: The collaboration of NEPKE and MAPEP has demonstrated that crossregional coordination is feasible and expands the number of transplants performed beyond the capability of either program alone, especially when combined with computer optimization and multiple-type matches of three-way, NDD chains, and list exchange chains.

Minimally invasive optimization of organ donor resuscitation: case reports.

Increased use of expanded donors requires optimal organ perfusion to prevent graft damage. In this regard, pulmonary artery catheters have been advocated to monitor hemodynamic status. Cost, catheter placement, and inconsistent management preclude broad use of pulmonary artery catheters. Esophageal Doppler monitoring also monitors hemodynamic status and can be instituted in minutes by an organ procurement coordinator, Concomitant assessment of acid-base balance using base excess and/or anion gap can help determine resuscitation efficacy. Esophageal Doppler monitoring is described to help salvage 2 hemodynamically deteriorating donors. Anion gap and corrected base excess identified poor resuscitation status in both donors and normalized after improvement in hemodynamic status. Compared to pulmonary artery catheters, esophageal Doppler monitoring may provide a more accessible means to assess and improve hemodynamic status. Base deficit and/or anion gap may determine resuscitation efficacy by exposing acid-base imbalance resulting from poor tissue perfusion. The full efficacy of this approach remains to be determined.

Vital role of medical examiners and coroners in organ transplantation.

Many people die owing to the shortage of donor organs. Medical examiners and coroners (MEs/Cs) play a vital role in making organs available for potential recipients. Medical examiners'/coroners' case data were collected using a structured confirmatory-recorded methodology for calendar years 2000-01 and were linked and analyzed with donor and transplant data from the United Network for Organ Sharing, predicting the nature and extent of the loss of donor organs. Nearly seven percent of ME/C cases were denied recovery during 2000-01. Because 353 and likely, 411 potential organ donors (PODs) were denied, as many as 1400 persons on transplant waiting lists did not receive organs because of ME/C denials. Problematically for pediatric patients awaiting transplantation, nearly half of all ME/C denials occurred in pediatric patients. Eighteen percent of PODs aged five or less and 44.2% of child abuse PODs were denied recovery by the ME/C. There were no (zero) denials in three of the five largest U.S. cities and in four states. Since 1994, two states have enacted legislation restricting the circumstances of ME/C denials, resulting in an 83% decrease in ME/C denials. Release of all organs from ME/C cases is needed urgently to protect the lives of those persons awaiting transplantation. Medical examiners and coroners deserve recognition for their efforts in advocating methods and/or regulation/legislation designed to achieve 100% release of life-saving organs for transplantation.