Maintaining organ viability between donation and transplantation is of critical importance for optimal graft function and survival. To date in pancreas transplantation, static cold storage (SCS) is the most widely practiced method of organ preservation. The first experiments in ex vivo perfusion of the pancreas were performed at the beginning of the 20th century. These perfusions led to organ oedema, hemorrhage, and venous congestion after revascularization. Despite these early hurdles, a number of factors now favor the use of perfusion during preservation: the encouraging results of HMP in kidney transplantation, the development of new perfusion solutions, and the development of organ perfusion machines for the lung, heart, kidneys and liver. This has led to a resurgence of research in machine perfusion for whole organ pancreas preservation. This review highlights the ischemia-reperfusion injuries assessment during ex vivo pancreas perfusion, both for assessment in pre-clinical experimental models as well for future use in the clinic. We evaluated perfusion dynamics, oedema assessment, especially by impedance analysis and MRI, whole organ oxygen consumption, tissue oxygen tension, metabolite concentrations in tissue and perfusate, mitochondrial respiration, cell death, especially by histology, total cell free DNA, caspase activation, and exocrine and endocrine assessment.

The standard technique for pancreas preservation for transplantation is Static Cold Storage (SCS). In this experimental study, we compare SCS to Hypothermic Machine Perfusion (HMP) of the pancreas to assess if the latter could safely prolong the ischaemia period prior to transplantation. We worked in 2 phases, first with organ preservation for 24hours and second, preservation for either 2 or 6hours before allotransplantation. In phase 1, exocrine injury markers were found to be non‐significantly lower, in the HMP group (n=3) versus SCS (n=3) after 24hours of preservation; amylase (p=0.2), lipase (p=0.3) and lactate dehydrogenase (p=0.1). In phase 2, 14 recipient diabetic pigs (after total pancreatectomy) received allotransplantations with n=4 and n=4 pancreases after HMP for 2 and 6hours versus n=3 and n=3 pancreases after SCS for 2 and 6hours respectively. There were no differences in recipient survival (p=0.7), mean survival was 14 days (0‐53 days). All recipients had allograft function defined as detectable C‐peptide and independent normoglycemia. We have not highlighted vascular thrombosis in all allotransplantations. This study reports the first successful pancreas allotransplantation after HMP preservation for up to 6 hours with no evidence of graft thrombosis.

Static cold storage (SCS) is the standard method for pancreas preservation prior to transplantation; however, it does not permit organ assessment. Normothermic reperfusion (NR) is utilized clinically for other organs to assess viability. Our aim was to develop NR using normothermic machine perfusion technique to simulate reperfusion at the time of transplantation, enabling evaluation of oxygenated hypothermic machine perfusion (HMPO2) as a newer strategy to optimize pancreas preservation. 13 porcine pancreases procured after circulatory death were divided into 3 groups: 4 pancreases preserved using SCS, and 2 groups preserved by HMPO2 (n = 4 and n = 5, differing by type of preservation solution). Duration of perfusion or cold storage was 6 hours before the 1-hour assessment using NR. Outcome measures were perfusion characteristics, biochemistry and change in tissue water mass as oedema assessment. During NR, the HMPO2 groups demonstrated better perfusion characteristics, normal macroscopic appearances, decreased water mass and one HMPO2 group demonstrated a response to glucose stimulation. Conversely, the SCS group showed an increased water mass and developed early macroscopic appearances of oedema, interstitial haemorrhage and minimal portal outflow. This study suggests that ex situ assessment of pancreases by NR is promising, and that HMPO2 may be better than SCS.