ABSTRACT
Background: With the growing acceptance of the role for the expansion of suitable indications for liver transplantation, such as selected cases of hilar cholangiocarcinoma and unresectable colorectal liver metastases, the imbalance between clinical need for liver transplantation and supply of suitable donor organs is likely to widen in Europe for the foreseeable future. Novel organ perfusion technologies are likely to play a fundamental role in maximising utilisation of all donor organs and facilitating the safe transplantation of marginal grafts. Herein we describe the initial experience of implementing Normothermic Machine Perfusion (NMP) in a liver transplant centre just before the onset of the COVID-19 pandemic. Methods: Retrospective analysis of a prospectively-maintained comprehensive database encompassing donor characteristics, perfusion parameters and post-transplantation outcomes. Results: Between February 2020 and October 2021 (20 months), 37 liver grafts were perfused with NMP and 23 proceeded to transplantation. The indications for NMP included logistics - 16 grafts (69%), further assessment of marginal grafts - 5 (22%) livers and facilitation of a predicted difficult hepatectomy (e.g. redo transplant) - 2 livers (9%). Overall, a total of an additional 15 livers, 3 kidneys and one pancreas were transplanted that absolutely could not have been transplanted without NMP (e.g. logistics, unacceptable cold ischaemic time with static cold storage) and a further 7 livers were successfully transplanted that may have been declined without the additional reassurance of dynamic functional assessment and safe prolongation of preservation time. No grafts were lost as a result of perfusion with NMP. Conclusions: NMP is a safe and effective technique for improving graft utilisation in liver transplantation and has become an integral component of routine clinical practice since its introduction in Edinburgh. As collective experience with NMP increases, the prognostic predictive ability of serum (and potentially bile) analysis on the machine is likely to improve graft utilisation further.