The Individual Impact of Machine Perfusion on Liver and Kidney on Donor Expansion in Simultaneous Liver and Kidney Transplantation.

Machine perfusion (MP) use for both organs can increase organ usage in simultaneous liver and kidney transplantation (SLKT). We analyzed 6,956 SLKT performed between 2015 and 2024 using the United Network for Organ Sharing database. The primary outcomes were the 1-year graft survival for kidney and liver. Donor types and MP use for liver and/or kidney were captured and associations with outcomes were evaluated. SLKT from Donation after circulatory death donors (DCD) increased from 4.5% in 2015 to 16% in 2023. The median Kidney Donor Profile Index (KDPI) has increased from 23% in 2015 to 28% in 2023. MP use for kidney and liver also increased from 21% to 51% and 0%-17%, respectively. KDPI >85% was an independent risk factor of 1-year kidney graft failure in the no kidney MP group [HR 2.03, 95% CI 1.20-3.44, p = 0.009], but not in the kidney MP group. DCD was found to be an independent risk factor of 1-year liver graft failure in the no liver MP group [HR 1.56, 95% CI 1.19-2.03, p = 0.001], but not in the liver MP group. MP for both organs may contribute to expanding the donor pool for SLKT without compromising post-transplant outcomes.