Hepatic hemodynamics after chronic obstruction of the biliary tract in the dog.

Hepatic blood flow was measured in 12 dogs before and two weeks after obstruction of the bile duct (BD) or sham operation, using the electromagnetic flowmeter technique. Eight dogs with obstructed BD revealed an 41 per cent decrease in total hepatic blood flow caused by an approximately equal percentage decrease in both hepatic arterial (HA) and portal venous (PV) flow, a decrease in arterial blood pressure, an increase in PV vascular resistance and little change in hepatic oxygen consumption. Four sham operated dogs showed minimal hemodynamic response. A dual mechanism for the hepatic hemodynamic consequences of chronic biliary obstruction is suggested: Decreased HA blood flow associated with diminished blood pressure and reduced PV blood flow resulting from raised intrahepatic PV vascular resistance.