Hypothermic oxygenated machine perfusion does not increase the risk of infection after liver transplantation: a retrospective cohort study

Background: Liver transplantation (LT) is a crucial treatment for end-stage liver disease, but the limited organ supply has led to the use of extended criteria donors (ECD). The implementation of dynamic preservation techniques like hypothermic oxygenated machine perfusion (HOPE) is crucial in improving outcomes for ECD grafts. However, graft contamination and infection are a concern. This study aimed to evaluate the risk of infections within 10 days from LT between HOPE and static cold storage (SCS) groups and postoperative complications. Methods: A retrospective cohort study was conducted, including LT recipients transplanted at a single-center from March 2016 to June 2023. Patients were divided into HOPE and SCS groups, and propensity score matching was used to select comparable cohorts. Data on patient and donor characteristics were analyzed. Results: After propensity score matching, a cohort of 370 (HOPE, n=185; SCS, n=185) patients was selected for analysis. The study found no significant differences in the rate of clinically relevant infections, microbiological positive samples, or donor-derived infections within 10 days between HOPE and SCS groups. Postoperative outcomes, as well as patient and graft survival, were also similar between the two groups. The study showed that HOPE is a feasible and safe approach, with a comparable risk of infection. Conclusions: The study results indicate that HOPE use in LT does not increase the risk of infection and is associated with similar patient and graft survival outcomes compared to SCS. These findings confirm the safety and efficacy of HOPE in LT and its potential to expand the donor pool without compromising recipient outcomes.