Initial Clinical Outcomes of Hypothermic Machine Perfusion in Deceased Donor Kidney Transplantation: A Pilot...

The shortage of donor kidneys has led to the increased use of marginal donors, including those from after circulatory death or extended criteria donors. Hypothermic machine perfusion (HMP) has shown better graft preservation than traditional static cold storage (SCS), particularly when cold ischemia time (CIT) is prolonged. This study evaluated the short-term outcomes of deceased donor kidney transplantation (DDKT) using HMP compared with SCS.

This pilot retrospective study included 16 DDKT patients at Jeju National University Hospital between April 2022 and July 2024. Seven grafts were preserved by SCS and nine by HMP. Donor, recipient, and perioperative characteristics were compared, as well as delayed graft function (DGF), 6-month graft and patient survival, and estimated glomerular filtration rate (eGFR). Given the limited sample size, multivariable adjustment or propensity-score analysis was not feasible, and results should be interpreted as exploratory.

HLA mismatch was higher in the SCS group than in the HMP group (4.86 ± 1.21 vs. 2.89 ± 1.45, P = .012). Donor renal function was superior in SCS group, with lower serum creatinine (1.34 ± 0.68 vs. 3.22 ± 0.70, P = .039) and higher eGFR (65.6 ± 30.9 vs. 29.1 ± 17.6, P = .010). CIT was significantly longer in the HMP group (297 vs. 894 min, P = .001). DGF occurred in 5 of 9 (55.6%) recipients in the HMP group and 1 of 7 (14.3%) in the SCS group (P = .103). Six-month graft and patient survival, and short-term graft function did not differ significantly. During HMP, flow increased and renal resistance decreased at 4 hours compared with baseline. Statistical power was limited, and post-hoc analysis suggested that approximately 20 patients per group would be required to detect differences in DGF with 80% power.

This pilot comparative study indicates that HMP is feasible for DDKT with prolonged CIT and yields comparable short-term outcomes to SCS. Dynamic perfusion parameters, including flow rate and renal resistance, may provide insights into early graft function, but validation in larger cohorts is required.