Novel oxygenation technique for hypothermic machine perfusion of liver grafts: Validation in porcine Donation after Cardiac Death (DCD) liver model.

Background: Hypothermic oxygenated machine perfusion improves outcomes in Liver Transplantation, but application is limited as O is supplied by a stationary circuit. A novel technique of O "pre-charge" in a portable pump would broaden use and further mitigate ischemia damage from organ transport.

Methods: Porcine DCD livers were randomized to static cold storage (SCS, n = 8) or hypothermic machine perfusion (HMP). HMP was stratified into HMP-O (n = 5), non-O open to air HMP-RA (n = 5), and non-O with sealed lids or no air HMP-NA (n = 5). HMP-O was "pre-charged" using 100% O delivered at 10 L/min over 15 min. Perfusate and tissue O tension (pO), liver biopsies, and fluid chemistries were analyzed.

Results: "Pre-charge" achieves sustained tissue and perfusate pO vs others. HMP-O results in decreased markers of hepatocyte injury: ALT (p < 0.05) and LDH (p < 0.05), lower expression of CRP and higher expression of SOD1 vs SCS. This suggests decreased inflammation and improved ROS scavenging.

Conclusions: "Pre-charge" is an effective technique, which allows portability and transport without an O source and improves graft parameters.