Hypothermic oxygenated machine perfusion for extended criteria donor allografts: Preliminary experience with extended organ preservation times in the setting of organ reallocation.

Abstract

In times of critical organ shortage, poor organ pool utilization and increased use of extended-criteria donor (ECD) allografts remain a major problem. Hypothermic oxygenated machine perfusion (HOPE) has emerged as a promising and feasible strategy in ECD liver transplantation (LT). However, potential safety limits regarding the duration of perfusion are yet to be explored. Besides marginal allograft quality (steatosis), prolonged cold ischemia time remains the most important factor for a high number of liver allografts being declined for transplantation. Two ECD-allografts were each allocated to two recipients, who proved to be unsuitable to receive the assigned allograft upon arrival at the transplant center. The organs were reallocated by Eurotransplant and accepted by our center for two different backup patients. During that time, HOPE was commenced and continued until the recipient hepatectomy was completed. Postoperative allograft function was assessed by serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, and International Normalized Ratio. Incidence of early allograft dysfunction (EAD), postoperative complications, and length of hospital stay were analyzed. HOPE was applied for 4h 35min and 4h 20min, resulting in a total cold preservation time of 17h 29min and 15h 20min, respectively. Both recipients displayed decreasing serum transaminases and bilirubin levels postoperatively. No EAD or major postoperative complications occurred in either patient. Serum ALT and AST levels were within the normal range at discharge. Extended HOPE enables the safe extension of preservation time for up to 18h in human LT. End-ischemic HOPE may significantly improve organ pool utilization, while simultaneously facilitating operating room logistics and preventing organ injury.