Biliary iodipamide and iodoxamate excretion as function of basal bile flow in normal, common bile duct obstructed and liver-damaged dogs.

The investigation was performed in 6 cholecystectomized chronic bile fistula dogs in which, except in complete common bile duct obstruction, the bile was diverted and replaced with a constant taurocholate infusion of 0.3 mumoles per min. per kg. Iodipamide and iodoxamate were i.v. infused at a rate of 6.7 mumoles per minute per kg for 30 minutes. Different degrees of extrahepatic obstruction were simulated by producing different intrabiliary pressure conditions. Progressive hepatic parenchymal disease was induced by oral administration of dimethylnitrosamine. In both conditions basal (precontrast) bile flow, maximum biliary excretion rate and bile concentration of the contrast agents decreased with increasing hepatic dysfunction. This investigation suggests that, regardless of the underlying mechanism, the bile iodine concentration required for radiographic visualization of the biliary system is no longer attained in intravenous cholangiography when the basal bile flow decreases below 2 microliter per min per kg in the presence of a physiologic bile salt plasma pool. In hepatic dysfunction alkaline phosphatase correlated better with the maximum biliary excretion rate and concentration of the contrast agents than SGPT, SGOT, and serum bilirubin and therefore seems to be the best parameter to predict the chance of a successful intravenous cholangiography.