Comparison between two warm ischemic models in experimental liver transplantation in pigs

Abstract

Background. Experimental models of warm ischemia in liver transplantation have been employed to study the mechanisms and treatment of ischemia reperfusion injury. Material. We compared a control group without (group A, n = 10) versus two models of warm ischemia of liver transplants in pigs: namely, occlusion of the hepatic artery and portal vein for 30 minutes (group B, n = 23) and extraction of the liver 60 minutes after cardiac arrest (group C, n = 5). Liver function tests, coagulation studies, and liver biopsies were performed during the first 24 hours post-liver transplant. Results. Clamping of the hepatic vasculature in group B produced a significant liver injury compared with the control group: elevation of the ALT and an abnormal 1-hour postrevascularization biopsy similar to that observed in the cardiac arrest group C. The transaminase levels were lower among group A animals (P < .05). But the hepatic synthetic functions as reflected in the protrombin time (PT) were not affected in group B versus group A. The alteration in PT with respect to the initial value was similar among group A and group B animals, which were significantly less than that in group C (P < .05). Conclusion. Occlusion of the hepatic artery and portal vein, a simple surgical maneuver, causes moderate damage to a liver graft but less alteration of hepatic synthetic function. Clamping of the hepatic vasculture obtains more long-term survivors after OLT than cardiac arrest. X E PERIMENTAL MODELS of warm ischemia in liver transplantation have been employed by numerous groups to study the type and mechanisms of ischemiareperfusion injury, to assess the relation of early to eventual function of the allograft, and to test therapeutic options. 1-3 We compared two models of warm ischemia clamping the hepatic artery and portal vein for 30 minutes, and extraction of the liver 60 minutes after cardiac arrest. Both experimental models have been used by our group in previous studies. [4][5][6] The comparisons included a group control in which the graft liver experienced no ischemia.

Safe time to warm ischemia and posttransplant survival of liver graft from non-heart-beating donors

“…NHBD programs have been used successfully in kidney transplantation, and were able to increase donor pool of kidneys by 40%. In the field of liver transplantation the use of livers from NHBD shows a less favorable clinical results, because of the limited hepatic tolerance against warm ischemic damage compared with kidneys [28][29][30] . Although several clinical and experimental studies have shown that liver can compensate 60 min of WIT during liver resection [31,32] , in transplantation settings, there were few studies about limit of the period of warm ischemia before transplantation.…”

Hemodynamics alterations during orthotopic liver experimental transplantation in pigs

“…Although such technique is attractive, Gruttadauria et al 7 demonstrated that anhepatic phase without venovenous could be easily tolerated during a 30-min period, which is usually sufficient to perform the two venous sutures preceding graft revascularization. Clamping of the supracoeliac aorta produced a significant liver injury compared with the control group 4,5,6,8,13,15,16,17,18,28 .…”

Transplante Hepático Ortotópico Experimental Em Suínos: Resultados Iniciais (I)

“…Este procedimento utilizando a técnica de Piggy-back em suínos não foi reproduzido no presente estudo. 13,14,15,16,20,21 Realizamos o procedimento utilizando dois animais por transplante, sendo doador e receptor. O treinamento no animal doador proporciona aprendizado relacionado à captação de múltiplos órgãos.…”

“…Trabalho realizado no Programa de Transplante Hepático Experimental do Hospital Universitário da Universidade Federal do Maranhão -UFMA. Patrocinado pelo CNPq -Conselho Nacional de Desenvolvimento Científi co e Tecnológico.Orlando Jorge Martins Torres, Érica Sampaio Barbosa, Noelia Dias Carneiro Barros, Patrícia Brandão Pantoja, Elisabeth Teixeira Noguera Servin, Poliana Cristina Oliveira Moreira, Edson Dener Zandonadi Ferreira, Raquel Aranha Viegas, Cristiany de Almeida Barros, Santiago Cirilo Noguera Servin, José Aparecido Valadão, Tereza Rachel Vieira Gomes, Natalino Salgado Filho, Waston Gonçalves Ribeiro aspectos técnicos que este procedimento tanto necessita e para realização de pesquisas experimentais ligadas ao transplante12,13,14,15,16,17 . Este estudo tem como objetivo apresentar os resultados iniciais do programa de transplante hepático ortotópico experimental em suínos da Universidade Federal do Maranhão.…”