Hepatic Ischemia-Reperfusion Injury according to Inflow Occlusion in Porcine Liver Surgery

Sim, Mun Sup; Jeon, Tae Yong; Jo, Hong Jae; Yea, Byung Kook; Cho, Yong Hoon; Baek, Seung Wan; Kim, Kyung Hoon

Abstract

PURPOSE
There are some methods for preventing massive intraoperative blood loss during major hepatic resection such as temporary vascular occlusion, but this can consequently lead to ischemia and reperfusion injury in the remnant liver. The purpose of this study is to assess ischemia-reperfusion (I/R) injury in a porcine hepatectomy model with continuous or intermittent inflow occlusion of a prolonged duration. METHODS: We performed right hepatic lobectomy in a porcine model with a liver ischemia lasting 120 mins; there was continuous (n=4) or intermittent (8 subsequent periods of 12 min ischemia and 3 min recirculation; n=4) inflow occlusion, and this was followed by 6 hours of reperfusion. We assessed hepatocytic injury by the serum levels of liver enzymes (AST, ALT, LDH), and we assessed the hepatocellular functions by the indocyanine green clearance test, inflammatory reactions by the serum levels of IL-6, and injury to the SECs (sinusoidal endothelial cell) by hyaluronic acid uptake. We compared these parameters during a preischemic period, a ischemic period and reperfusion period between the two groups. RESULTS: There were significant differences in the serum AST levels, IL-6 levels and HA uptake between the continuous and intermittent occlusion groups. In the intermittent occlusion group, we observed 1) less severe hepatocytic injury (p= 0.041) ; 2) more preserved HA uptake meaning less I/R injury (p=0.031) ; and 3) less inflammatory responses in the reperfusion period (p=0.045). CONCLUSION: During prolonged hepatic ischemia in a porcine model, the intermittent inflow occlusion method seemed to cause less hepatocellular injury and less SEC injury when compared to the continuous occlusion method. This means that we can expect less reperfusion injury in the intermittent inflow occlusion during a major hepatic resection with a prolonged ischemia.