Hyperperfusion syndrome in small-for-size livers

Abstract

Background: Portal hyperperfusion in small-for-size livers might seriously impair postoperative liver regeneration. Using an experimental model, we investigated splenectomy as a measure to reduce portal blood flow and its impact on postoperative recovery following extended liver resection.

Method: Wistar rats underwent partial (90%) hepatectomy with or without splenectomy under temporary inflow occlusion (30 min). In addition to 10-day survival rate, laser Doppler flowmetry of hepatic blood flow and fluorescence microscopic analysis of hepatic microcirculation were performed to assess the effect of splenectomy on initial microvascular reperfusion of liver remnants.

Results: While postischemic perfusion failure was comparable between both groups, portal blood flow was significantly reduced after simultaneous splenectomy (3.5+/-0.4 vs. 5.4+/-0.4 ml/min). Moreover, red blood cell velocity and volumetric blood flow were reduced in splenectomized animals. These animals experienced lower AST levels (421+/-36 vs. 574+/-73 U/l) and a significantly increased survival rate, reaching 6.6+/-1.3 vs 2.6+/-0.8 days.

Conclusion: Simultaneous splenectomy significantly reduced the risk for postoperative hyperperfusion syndrome in small-for-size livers. Shear-stress-induced liver injury was diminished due to a significant reduction of portal venous blood flow, which positively influenced postoperative regeneration resulting in significantly higher survival.