The length of the warm ischemic interval in lung donation after circulatory death does not impact post-transplantation outcomes

Introduction

Transplantation of lungs obtained by donation after circulatory death (DCD) has increased the number of available organs. This study aims to determine how donor characteristics and current procurement processes (specifically, agonal and warm ischemic times) influence the outcomes experienced by the recipients of DCD lung transplants.

Materials and Methods

An analysis was conducted on United Network for Organ Sharing data collected from January 2018 to June 30, 2024, with a focus on adult recipients of double lung transplants with a DCD donor. Withdrawal-to-flush and agonal-to-flush times were divided into three non-overlapping intervals. Univariable comparisons were performed on donor and recipient characteristics and post-transplantation outcomes between intervals. Kaplan-Meier analyses were used to determine the impact of agonal and warm ischemic times on posttransplant survival.

Results

The median times for withdrawal-to-flush and agonal-to-flush were 28 and 25 minutes, respectively, with closely aligned intervals. Donors in the short agonal-to-flush category were generally older and tended to be female, with no other significant donor characteristics associated with the time intervals. There were no observed associations between agonal or warm ischemic times and post-transplant outcomes, including primary graft dysfunction, ventilator dependency, and acute rejection. Kaplan-Meier survival analysis revealed no significant differences in survival between the groups (p=0.47 for withdrawal-to-flush; p=0.57 for agonal-to-flush).

Conclusions

This study suggests that current variations in withdrawal-to-flush and agonal-to-flush times are not associated with DCD lung transplant outcomes. The findings underscore the need for expanding strategies to increase the utilization and availability of DCD lungs.