The landscape of liver preservation has significantly changed during the past decade. The traditional cold static storage has been supplemented with novel strategies of cold and warm oxygenated perfusion as alterative or additional preservation techniques. While oxygenated liver perfusion was initially developed to reduce graft injury and increase the donor pool, the opportunity for graft assessment and repair during perfused graft preservation has triggered significant interest. The future of perfused liver preservation will likely be the combination of normothermic regional perfusion in the donor, followed by cold and warm oxygenated perfusion, depending on the donor type. Prolonged liver perfusion will offer exciting opportunities for graft modification in the years to come.

Over the years, lung preservation strategies have evolved significantly, transitioning from intracellular to extracellular solutions. Notably, Perfadex, ET-Kyoto, and EP-TU solutions have become widely accepted. The inception of ex vivo lung perfusion (EVLP) and the adoption of 10 degrees preservation have substantially transformed lung transplantation procedures.

Yet, the journey towards optimal organ preservation continues. The ultimate goal is to substantially reduce cellular metabolism, mirroring a state of metabolic arrest. Such a state is observed in hibernation, where mammals like squirrels and bears reduce their basal metabolism to 1-25% of normal levels to survive harsh conditions. Recent advances demonstrate the possibility of pharmacologically inducing a similar hypometabolic state at the cellular level.

We delve into the potential of augmenting lung preservation duration by integrating hibernation-inducing agents into the extracellular fluid lung preservation solution and the EVLP perfusate. Our goal is to safely induce a hypometabolic state in solid organs, which may potentially redefine long-term preservation of organs.

The use of high-risk kidney grafts for transplantation requires optimization of pre-transplant evaluation and preservation reconditioning strategies to reduce organ discard rates and improve short- and long-term clinical outcomes.

It is becoming further recognized that active oxygenation plays a central role in dynamic preservation strategies that realign mitochondria and restore cellular energy profiles, regardless of storage temperature. Reducing oxygen-related mitochondrial succinic acid accumulation improves the harmful effects of ischemia-reperfusion injury.

The difference between normothermic and hypothermic machine perfusion with respect to organ evaluation, preservation and reconditioning, as well as logistics and economic implications, are factors to be considered in each clinical field. Therefore, these various techniques should be considered as complementary to the perfusion strategies that are selected according to functional intention and resource availability.

In this symposium, we would like to present an overview of the current clinical evidence for normothermic and oxygenated hypothermic machine perfusion either as a continuous or end-ischemic preservation strategy.

Background: Machine perfusion (MP) has not been widely used because of its low demand in Japan. Here, we report the first clinical trial of machine perfusion for kidney transplantation in Japan. We used the domestic machine to preserve the graft. The flow rate, perfusion pressure, renal resistance, and temperature were monitored during continuous hypothermic perfusion. Results: From August 2020 to the present, 15 cases of perfusion-preserved kidney transplantation have been performed. Of these, eleven and four cases were performed using organs donated after brain death (DBD) and cardiac death (DCD), respectively. The average age of the recipients was 54.5 years. The average total ischemic time was 693 minutes. The average MP time was 149.8 minutes. A total of 9 cases had delayed graft function. The best creatinine level during hospitalization was 1.30 mg/dL. There were no primary non-functional cases and perfusion preservation was safely performed in all cases. Conclusions: we present this report as the first clinical trial on machine perfusion for kidney transplantation from marginal donors with DBD and DCD in Japan

In kidney transplantation, ischemia-reperfusion injury results in a high rate of delayed graft function.Methods: Thirty patients underwent cadaveric kidney transplantation from January 2015 to July 2022. These patients were classified into two groups according to 12 patients received transplants from extended criteria donors(ECD) and 18 received them from standard criteria donors(SCD).Three of ECD group were preserved by machine perfusion. We used the CMP-X08 perfusion devise (Chuo Seiko Co.,Ltd) and Belzer MPS solution to preserve the donated organ.Results: Patient survival was observed for all patients. Renal function at 3months and 1year was better in SCD group. In ECD group, renal function at discharge and 3months better in simple cold storage(SCS), but renal function after 6months was better in hypothermic machine perfusion(HMP).There was no significant difference in graft survival between ECD and SCD. Conclusion: There were no significant differences in outcomes of our patients who received transplants from ECD or SCD. It was suggested that kidney transplantation with machine perfusion preservation for ECD group would maintain good renal function.

The aim of this study was to examine the influence of machine perfusion (MP) and normothermic regional perfusion (NRP) on the utilization and outcomes of liver transplantation (LT). Using US national data, 4642 donation after circulatory death (DCD) donors between 2016 and 2021 were analyzed. 4542 were with static cold storage(SCS), 79 were with MP(1.7%), and 21 were with NRP(0.5%).The utilization rates of liver in DCD with MP or NRP were significantly higher (P=0.001; 92.4% or 95.2% vs 70.4%). There were no graft failure with primary nonfunction or ischemic cholangiopathy after LT with MP or NRP. MP or NRP significantly increased the utilization rate of livers with favorable outcomes after LT. Increasing use of MP or NRP should be considered in low utilization donors to expand donor pool.

Background and Aim: The development of a machine perfusion (MP) device that can perform both normothermic perfusion (NMP) and hypothermic oxygenated machine perfusion (HOPE) more safely and for a longer period of time is demanded. We report our efforts to develop a MP. Methods: The developed MP device employed perfusion using hydraulic gradient. 1.Using a porcine model, grafts from donors after circulatory death (DCD), 1 hours after cardiac arrest and long-term 14 hours cold ischemic model of donation after brain death (DBD) were transplanted. DCD grafts were placed in a negative pressure sealed container to remove thrombus and to improve perfusion kinetics. Both models conducted 3 hours NMP (37 degree Celsius). 2. We developed a HOPE device. Results: In both DCD and DBD model, bile production and metabolic improvement, the survival for 3 days after transplant were confirmed. For developing HOPE device, pumpless perfusion with cold perfusate (10 degree Celsius) was supplied. Conclusion: We succeeded a MP device for both NMP and HOPE. We continue to improve and establish the MP device for liver transplantation in Japan with considering practical situation of organ donation in Japan.