Un nuovo sistema di perfusione parenchimale per la preservazione del graft epatico per trapianto: valutazione sperimentale sul piccolo e grande animale

Background In liver transplantation one of the most important promblem which has not a solution yet is the large discrepancy between supply and demand for liver transplantation. To expand the pool of organs we should find the way to utilize marginal livers like the Non-heart-beating-donors ones and the fatty grafts. The use of these livers is associated with high incidence of post-operative primary dysfunction caused by the damage due to the Cold Storage preservation in the context of the process of ischaemia- reperfusion in extreme hypothermia (4° C). The utilization of new methods in the conservation of hepatic grafts like Machine Perfusion becomes necessary, especially for its ability to reduce the damage of ischaemia-reperfusion in hypothermia. The great potentiality of this Machine in sane and marginal organ preservation and the number of works which took place about it, stimulated us to the deepen this argument. Purpose We decided to create a experimental model of Machine Perfusion for pigs and to test it with different temperatures to obtain the best condition of perfusion and graft preservation. We based our study on the various works that can be find in literature and on the research developed by the Università di Pavia on rats. Methods We used in our experiments 15 Landrace pig of the weight of 22 kilos each. We divided them in three groups of study. Group C: after hepatectomy the pig liver was preserved in Cold Storage (4° C) for 8 hours. Group N: after hepatectomy the pig liver was perfused in Normothermic Machine Perfusion (37°C) for 8 hours. Group I: the pig liver was perfused in Moderate Hypothermic Machine (20°C). After the preservation, all the 15 livers were tested with a rewarming (37°C) of 2 hours. During the two hours of the experiment we performed samples of blood and biopsies and we also valuated the indocianine green clearance. Results The results obtained by the histology, the functional test and biochemical levels of AST, ALT and LDH, in the moderate hypothermic perfusion prove the superiority of this machine . Conclusion It is concluded after these experiments the great ability of 20°C Machine Perfusion in pig's liver transplantation. We think that this method of preservation will be able to improve the pool of donors using NHBD livers and fatty livers. In future our research will deepen the problematic connected with the preservation of marginal organs, in particular of steatotic livers