Ex-vivo lung perfusion: National trends and post-transplant outcomes.

Background: Ex-vivo lung perfusion (EVLP) has potential to expand donor lung utilization, evaluate allograft viability, and mitigate ischemia-reperfusion injury. However, trends in EVLP use and recipient outcomes are unknown on a national scale. We examined trends in EVLP use and recipient outcomes in the United States.

Methods: Adult patients undergoing lung transplant between 2013 and 2023 were identified in the Standard Transplant Analysis and Research-Organ Procurement and Transplantation Network database. Effects of EVLP use on center volume changes were assessed using difference-in-difference analysis. Multivariable logistic regression was used to evaluate associations between EVLP use and recipient 30-day mortality, post-operative length of stay, grade 3 primary graft dysfunction (PGD), and need for mechanical ventilation at 72 hours.

Results: Of 23,807 lung transplants during the study period, 813 utilized EVLP. While transplant volume increased over time, this was not attributable to EVLP use. Recipients in the EVLP cohort demonstrated increased 30-day mortality [3.8% vs 2.4%; OR 1.57 (1.02-2.41); p = 0.040], mechanical ventilation at 72 hours [40.2% vs 31.2%; OR 1.58 (1.33-1.87); p < 0.001], and longer postoperative length of stay (35.8 vs 30.0 days; IRR 1.19 (1.18-1.21); p < 0.001) compared to the non-EVLP cohort. No difference in grade 3 PGD was found between groups [14.5% vs 14.1%; OR 1.04 (0.80-1.34); p = 0.791].

Conclusions: Although annual transplant volume has increased, the upward trend cannot yet be attributed to EVLP use. In the largest study to date, our results suggest outcome differences between EVLP and non-EVLP recipient cohorts. This motivates future work to characterize how patient selection and institutional factors influence outcomes with EVLP use.