Reducing cold ischemia time by donor liver “back‐table” preparation under continuous oxygenated machine perfusion of the portal vein

Introduction Cold ischemia time is a well‐known risk factor for the development of non‐anastomotic biliary strictures (NAS) after liver transplantation. End‐ischemic hypothermic oxygenated machine perfusion (HOPE) of DCD liver grafts reduces the incidence of NAS, and has the potential to reduce cold ischemia times. We hypothesized that if a part of the back‐table procedure could be performed under continuous HOPE, cold ischemia times would be reduced. Methods In this prospective observational cohort study, all nationwide declined livers that underwent DHOPE‐NMP between July 1st 2021 and January 1st 2022 were included. The back‐table of ten consecutive high‐risk donor livers was performed with ongoing HOPE. Sixty DHOPE‐NMP procedures (August 1st 2017–July 1st 2021) with a conventional back‐table procedure functioned as a control group. Results Compared to the control group, this technique led to a decrease in non‐oxygenated back‐table time from median 74 min (IQR 58–92 min) to median 25 min (IQR 21–31 min), p < .01. Median total cold preservation times were reduced from 279 min (IQR 254–297) to 214 min (IQR 132–254), p < .01. Conclusion Cold ischemia time of liver grafts can be successfully reduced by over one hour by using portal vein only HOPE during back‐table preparation.