Liver transplant practices in the era of normothermic machine perfusion in the United States

BACKGROUND Normothermic liver machine perfusion (NMP) is a novel technology used to preserve and evaluate the function of liver allografts. AIM To assess NMP utilization in liver transplant (LT) practices. METHODS All adult deceased-donor LT recipients between January 2021 and September 2023 in the United States were analyzed. Outcomes including discard rates, survival, preservation time and timing of surgery were compared between two groups: NMP vs non-NMP. RESULTS Between 2021 and 2023, NMP was utilized in 1493 (6.3%) of all LTs in the United States. Compared to non-NMP group, NMP group had lower allograft discard rate (6.5% vs 10%, P < 0.001), older recipients’ age (median: 47 vs 42 years, P < 0.001), and higher utilization of donors from donation after circulatory death (DCD) (55% vs 11%, P < 0.001). NMP group also had longer distances between recipient and donor hospitals (median: 156 vs 138 miles, P < 0.001), longer preservation time (median: 12.2 vs 5.8 hours, P < 0.001), and more daytime reperfusion (74% vs 55%, P < 0.001). Post-transplant survival outcomes were comparable between the two groups. In a subgroup analysis of NMP, recipients in the long preservation time (≥ 8 hours) group had higher daytime reperfusion (78% vs 55%, P < 0.001) and similar post-transplant survival when compared to the short preservation time (< 8 hours) group. CONCLUSION The utilization of NMP is associated with lower discard rates and increased DCD organs for LT. NMP allows for prolonging the preservation time and increased occurrence of daytime LT, without any impact on the survival outcomes.