Machine Perfusion Parameters and 1-Year Outcomes in High KDPI Kidney Transplantation: A Single-Center Cohort Study

Kidney donor profile index (KDPI) was intended as an objective measure of donor organ quality but its utility in kidney allograft assessment has been questioned. High KDPI kidneys (KDPI ≥85) present a source of transplantable allografts.

A retrospective review was conducted on a single-center database for KDPI ≥85 transplants from 2013 to 2023. Allografts placed on hypothermic machine perfusion (HMP) with a flow ≥100 ml/min and resistance ≤0.2 mm Hg/mL/min (Group A) were compared to those with a flow <100 mL/min and/or resistance >0.2 mm Hg/mL/min (Group B).

We identified 71 patients who received KDPI ≥85 kidneys from 59 donors. The average KDPI was 90%. The average donor age was 61 years; 75% had hypertension, 41% had diabetes, 2.4% had hepatitis C, and 35% were donors after circulatory death. Group A included 30 recipients; Group B included 42 recipients. Average flow and resistance were 157 mL/min and 0.17 mm Hg/mL/min in Group A and 115 mL/min and 0.27 mmHg/mL/min in Group B. Mean serum creatinine and eGFR at 1 year were 1.72 mg/dL and 42.4 mL/min/1.73 m² for Group A and 1.74 mg/dL and 43.1 mL/min/1.73 m² for Group B (p = .6). Delayed graft function occurred in 43% of Group A and 61% of Group B (p = .07). Overall, 1-year graft survival and patient survival were 90.0% and 95.1%, respectively.

High KDPI grafts may represent a strategy to mitigate kidney waitlist burden in selected patients. In this single-center retrospective cohort, we observed no statistically significant differences in 1-year graft function, graft survival, or patient survival between grafts stratified by pre-specified HMP flow and resistance thresholds.