The effect of normothermic machine perfusion on acute kidney injury following liver transplantation: a propensity score-matched, retrospective, single-centre, cohort study.

BACKGROUND

Normothermic machine perfusion (NMP) is increasingly used for liver transplantation, but its effect on post-transplantation acute kidney injury (AKI), especially in recipients with renal dysfunction, remains unclear. We evaluated whether NMP was associated with lower early renal injury after deceased donor liver transplantation compared with static cold storage (SCS), including recipients with pre-existing AKI or chronic kidney disease (CKD).

METHODS

This retrospective, single-centre, cohort study at Cleveland Clinic included deceased donor liver transplantation recipients transplanted between January 2019 and January 2025 with at least 12 months of follow-up. The primary outcome was new post-transplantation AKI by KDIGO serum creatinine criteria. Renal outcomes were assessed using KDIGO staging and validated core outcome set endpoints. Associations were evaluated using mixed-effects logistic regression, and NMP recipients were matched 1:1 to SCS recipients using propensity scores.

FINDINGS: 893 recipients were included; 319 (36%) received NMP. In multivariable analysis, NMP was associated with lower odds of AKI (odds ratio [OR] 0.70, 95% CI 0.46-0.94; p = 0.036) and new renal replacement therapy (RRT; OR 0.10, 95% CI 0.017-0.64; p = 0.015). Among 213 matched pairs without pre-existing AKI or CKD, AKI occurred in 62 (29%) NMP recipients vs 88 (41%) SCS recipients (p = 0.008), acute kidney disease in 95 (45%) vs 122 (57%; p = 0.009), and stage 3 AKI in seven (3%) vs 15 (7%). Among recipients with pre-existing AKI or CKD, postoperative peak creatinine was lower with NMP in unmatched (2.22 mg/dL [IQR 1.72-2.86] vs 2.71 mg/dL [1.85-3.47]; p = 0.017) and matched cohorts (2.04 mg/dL [1.64-2.34] vs 2.87 mg/dL [2.65-3.34]; p < 0.001).

INTERPRETATION: NMP was associated with a modest but clinically relevant reduction in early renal injury after liver transplantation. These effects were most pronounced in recipients without pre-existing renal dysfunction and remained directionally consistent in high-risk recipients.

FUNDING: None.