1. a surgical technique in which the hepatic portal vein is joined to the inferior vena cava. Blood draining from the abdominal viscera is thus diverted past the liver. It is used in the treatment of portal hypertension, since - by lowering the pressure within the veins of the stomach and oesophagus - it prevents serious bleeding into the gastrointestinal tract.
2. any of the natural communications between the branches of the hepatic portal vein in the liver and the inferior vena cava.
Medical dictionary. 2011.