Influence of lung donor agonal and warm ischemic times on early mortality: Analyses from the ISHLT DCD Lung Transplant Registry

Abstract

Background: In this study we aimed to assess the impact of agonal time and warm ischemic time on early survival in Category III donation-after-circulatory-death (DCD) donor lung transplants (LTxs) using data reported to the International Society for Heart and Lung Transplantation (ISHLT) DCD Lung Transplant Registry.

Methods: In this retrospective study, data were analyzed for 507 DCD LTxs done between January 2005 and June 2015. DCD lung donor agonal time (defined as withdrawal of life support to cessation of cardiac output) and warm ischemic time (WIT; defined as donor systolic blood pressure <50 mm Hg to cold pulmonary artery flush) were divided into 3 clinical timing categories (<30 minutes, 30 to 60 minutes, >60 minutes) and 3 tertiles. Univariate analysis was undertaken for all categorizations, and Day 30/Day 365 Kaplan‒Meier survival rates were calculated and compared. Multivariable analysis included Cox proportional hazards regression models to estimate hazard of 365-day mortality.

Results: Four hundred sixty-five and 301 DCD LTxs had data to analyze in the agonal and warm ischemic time groups, respectively. Day 30 and Day 365 post-transplant survival overall were 96% and 90%, respectively, and not statistically different according to agonal or WIT category or tertile.

Conclusions: Current experience with DCD Category III LTx does not show a relationship between the duration of donor agonal phase or warm ischemic time up to 60 minutes and early survival. These results suggest the true limits of clinical DCD allograft warm ischemic times may not yet be reached. Global variations in clinical DCD practice are apparent. Continued accurate recording and analyses of DCD processes is warranted.

Keywords: donation after circulatory death; donor lung; graft ischemia; lung transplantation; mortality; organ donation.