Does Normothermic Machine Perfusion Improve Kidney Transplant Outcomes?

Full access

A period of normothermic machine perfusion (NMP) is feasible and safe before deceased-donor kidney transplantation but does not reduce the rate of delayed graft function (DGF) compared with standard static cold storage (SCS), reports a trial in Nature Medicine.

The randomized trial included 338 patients at four U.K. centers who were undergoing kidney transplantation from donation after circulatory death (DCD) donors. All kidneys underwent SCS, with a total cold ischemic time of approximately 800 minutes. After SCS, kidneys in the intervention group underwent a 1-hour period of NMP.

Intention-to-treat analysis included 147 kidneys assigned to SCS only and 143 to SCS plus NMP. DGF, defined as the requirement for dialysis within 7 days after transplantation, was the main outcome of interest.

The rate of DGF was almost identical between groups: 58.5% with SCS alone and 60.7% with SCS plus NMP. Patient and graft survival, acute rejection, and 12-month kidney function were similar as well. There were no significant differences in adverse events, including transplant thrombosis or infectious complications.

Kidneys from DCD donors are an important source of organs for transplantation but are susceptible to cold ischemic injury, which may lead to DGF. In the emerging NMP technique, donor kidneys are perfused with a warmed, oxygenated, red cell-based solution, producing a near-physiologic state that enables functional testing. To date, the new report is the first randomized, multicenter trial comparing NMP with conventional SCS in DCD kidney transplantation.

The results show no reduction in DGF with a period of NMP before transplantation of DCD kidneys. The researchers write, “Nonetheless, we have demonstrated that this new technology for kidney preservation is feasible, safe and suitable for clinical application” [Hosgood SA, et al. Normothermic machine perfusion versus static cold storage in donation after circulatory death kidney transplantation: A randomized controlled trial. Nat Med 2023; 29:1511–1519. doi: 10.1038/s41591-023-02376-7].