Effect of acute portal hypertension on hepatosplanchnic hemodynamics and liver function.

Acute prehepatic portal hypertension was mechanically induced in Göttingen minipigs. A 125% increase in portal pressure resulted in a significant decrease in estimated hepatic blood flow. The decrease in blood flow was accompanied by a 25% reduction in the 'true' clearance of indocyanine green and an 18% decrease in splanchnic oxygen consumption. Judged from the splanchnic elimination rate of galactose, the functional liver cell mass was not altered by portal banding, and an unaltered lactate to pyruvate ratio in hepatic venous blood indicated that no functional parts of the liver became severely hypoxic.