Hypothermic Machine Perfusion as an Alternative to Biopsy Assessment in Transplantation of Kidneys Donated After Cardiocirculatory Death: A Pilot Study

Abstract

Background: Transplantation of kidneys from donation after cardiocirculatory death (DCD) donors is becoming an ever-increasing reality. So far, biopsy histologic assessment is the main parameter for evaluation of graft suitability, but it has several drawbacks and has poor reliability. The aim of this study is to verify if real-time renal resistance (RR) measurement during hypothermic machine perfusion (HMP) can be used as a reliable parameter to evaluate the quality of grafts from DCD and extracorporeal membrane oxygenation (ECMO) donors.

Methods: From January 2015 to September 2018, HMP has been systematically applied to all organs from DCD and ECMO donors. All grafts underwent preimplantation biopsy histologic assessment with Karpinski's score. Single kidney transplants (SKTs) or double kidney transplants (DKTs) were performed according to biopsy score results. Kidneys were considered suitable for transplant if RR reached ≤ 1.0 within 3 hours of perfusion. RR trend and postoperative outcome were analyzed considering biopsy score and donor type.

Results: A total of 30 kidneys (15 from DCD and 15 from ECMO donors) were used to perform 26 transplants (22 SKTs and 4 DKTs). Considering RR trend, all grafts were considered suitable for transplant within 1 hour of perfusion. Biopsy confirmed this result in all cases, and median score was 3 (range, 0-7). SKT score kidneys had lower starting RR than DKT ones (1.88 vs 2.88; P = .04) but identical final RR (0.58 vs 0.57; P = .76). DKT recipients had faster postoperative creatinine reduction than SKT recipients but similar postoperative day 30 value (1.42 vs 1.15 mg/dL; P = .20). No differences were found between DCD and ECMO grafts in terms of RR trend and postoperative outcome.

Conclusions: HMP can be an alternative to histologic biopsy assessment for evaluation of transplant suitability of DCD and ECMO kidneys. If acceptability threshold is reached, SKT can be performed in all cases. ECMO donors should be considered like DCD donors.