Portal hypertension

Abstract

Portal hypertension is defined as the increase of portal pressure beyond 10 mmHg. As most of the cases of portal hypertension are caused by Hepatic Cirrhosis, the prevailing pathophysiologic theory explaining increased portal pressure in the twentieth century was the increased resistance to blood flow due to hepatic fibrosis and architectural distortion. Most of the research was done in dogs with complex research models. It was in the early seventies that inconsistencies of this theory came out, suggesting other possible explanations. In 1983 R. Groszmann and collaborators started to work with a model of portal hypertension with rats, described in 1951 by P.C. Reynell. These studies shed new light on pathophysiology of portal hypertension, adding new interpretations to old findings called the forward flow theory opposed to the former backward flow theory. These new findings provided new explanations for the managing of hemorrhage and therapeutics of the portal pressure increase.