To Pump or Not to Pump: A Comparison of Machine Perfusion vs Cold Storage for Deceased Donor Kidney Transplantation

BackgroundA recent multicenter European trial has demonstrated reduced rates of delayed graft function when kidneys undergo machine perfusion before transplantation. This study was undertaken to evaluate the impact of machine perfusion on early kidney transplant function in the United States.Study DesignRetrospective review of United Network for Organ Sharing data from January 1, 2005 through March 31, 2011 was undertaken. Comparisons were made between kidneys that underwent machine perfusion (MP) vs cold storage (CS) alone in terms of delayed graft function (DGF). The analysis was performed in a cohort of MP and CS kidneys matched by propensity scoring, as well as in a cohort of paired kidneys from the same donor in which one underwent MP and the other underwent CS. Secondary end points analyzed included recipient length of stay after transplantation and graft survival.ResultsIn the overall cohort, rates of DGF were similar for MP and CS kidneys (25.7% vs 25.0%; p = 0.082), likely due to preferential use of MP in marginal kidneys. In the propensity matched cohort, MP was associated with significantly lower rates of DGF compared with CS (21.1% vs 29.1%; p < 0.001). These findings were corroborated by the paired kidney analysis, in which DGF occurred in 19.7% of the MP group compared with 27.5% of the CS group (p < 0.001). There was no difference in the hazard for graft failure between the MP and CS group in the propensity matched analysis (hazard ratio = 0.98; p = 0.622) and in the paired kidney analysis (hazard ratio = 1.02; p = 0.839).ConclusionsMachine perfusion of deceased donor kidneys results in significantly decreased rates of DGF.