Hepatic hypoperfusion after intestinal reperfusion

Background. Intestinal ischemia-reperfusion injury (IIR) induces hepatic and pulmonary dysfunction and thus has been used a a model of multiple organ failure syndrome. This study examines the hypothesis that hepatic blood flow is markedly reduced in this injury model. Methods. Sprague-Dawley rats underwent 120 minutes of intestinal ischemia and 60 minutes of reperfusion (IIR). Hepatic blood flow was measured with radiolabeled microspheres and Doppler flow probes. Hepatic dysfunction was quantitated by measuring bile flow and serum alanine aminotransferase and hepatic tissue adenosine triphosphate levels. Sham-operated animals served as controls. Results. Intestinal ischemia reduced portal flow by 66% when compared with sham-operated animals (p = 0.0001) but had no effect on hepatic arterial flow. In contrast, reperfusion reduced hepatic artery flow by 80% when compared with controls (p = 0.002) with most of this change occurring within 5 minutes of reperfusion. IIR induced a 63% reduction in bile flow (p < 0.05), a fivefold rise in serum alanine aminotransferase level (p < 0.0002), and a 33% reduction in hepatic adenosine triphosphate level (p < 0.05). Conclusions. These data suggest that IIR induces profound hepatic hypoperfusion, which is temporally related to acute hepatic dysfunction. This observation suggests that hepatic ischemia may contribute to IIR-induced liver injury.