Donor livers were obtained from the New England Organ Bank (NEOB) with consent for research from the family after being turned down for clinical transplantation. Extubation of donors after circulatory death was performed by the primary service, which was also responsible for declaration of death 5 minutes after circulatory cessation. The procurement procedure did not begin until after declaration of death. Standard procurement technique includes an in situ flush with University of Wisconsin (UW) solution, intra-abdominal cooling with ice, and an additional back table UW flush. The gallbladder was incised, aspirated of bile, and irrigated with saline. The common bile duct was flushed with UW solution. The relative warm ischemic time for DCD livers is defined as the time between extubation and in situ cold flushing, whereas absolute warm ischemic time begins after circulatory cessation and ends at in situ cold flushing. Donor livers were transported in sterile bags cooled on ice. On arrival at our center and during the priming of the machine perfusion system the donor liver was prepared for connection to the system. The portal vein and hepatic branches of the celiac trunk and/or superior mesenteric artery were dissected free. The portal vein was cannulated distally with a section of tubing (Masterflex 24 L/S, Cole Palmer, Vernon Hills, IL). The aortic segment was opened and the celiac trunk was cannulated at the origin with a vessel cannula (Medtronic, Minneapolis, MN). Other branches of the celiac trunk were tied using 0 silk sutures. The cystic duct was ligated and the gallbladder flushed of residual bile. The common bile duct was cannulated with a vessel cannula, which was then connected to a section of tubing to allow bile collection. All cannulae were secured using 0 silk sutures.
Approval was obtained from the NEOB for the perfusion of discarded human donor livers and this study was declared exempt by the Massachusetts General Hospital (MGH) institutional review board (IRB # 2011P001496).