Experimental Evaluation of Preoperative Hepatic Venous Occlusion for Hepatectomy Combined with Hepatic Vein Resection

Abstract

The aim of this study was to investigate whether preoperative occlusion of the hepatic vein might obviate the need for hepatic vein reconstruction after hepatectomy combined with hepatic vein resection. In laparotomized beagles, the left and middle hepatic veins were exposed along the hepatic edge and theproximal portion was obstructed by ligations approximately 1.5cm in length to establish hepatic venous occlusion (HVO). Two experimental groups were studied: group I, controls sacrificed immediately after HVO (n=7); group II, dogs sacrificed two weeks after HVO (n=7). After sacrifice, retrograde hepatic venography was performed to compare collateral formation in the two groups. In group I, retrograde hepatic venograms showed complete lack of opacification of the left and middle hepatic venous trees without collateral formation. In contrast, in group II, the left and middle hepatic venous trees, distal to the obstructed portion, were clearly opacified through a number of collaterals. Portal venous pressure increased immediately after HVO. However, the level returned to baseline 40min after HVO. In group II, macroscopic findings of the liver including color and size at sacrifice were similar to those before HVE, and congestion was not demonstrated histopathologically. Although GOT showed a transient elevation after HVO, serum bilirubin levels were maintained within normal range throughout observation. These results suggest that preoperative HVO may obviate the need for hepatic vein reconstruction in patients with liver cancers requiring hepatectomy with hepatic vein resection.