[Increased bile acid retention in biliodigestive Roux-Y anastomosis in animal experiment].

In an experimental study on 65 rats the influence of different Roux-Y biliary anastomoses on the enterohepatic bile acid circulation was investigated. Long (10 cm) and short (3 cm) isoperistaltic and long (10 cm) anisoperistaltic Roux-Y loops were studied and compared to sham-operated controls. 75-SeHCAT a y-labeled synthetic bile acid was used for assessment of enterohepatic circulation. Hepatic excretion and enteric bile flow was investigated by 99m-Tc-HIDA. Intestinal transit time was evaluated by 51-Cr-EDTA an inert marker of intestinal contents. Animals with biliary anastomoses showed an increased retention of the synthetic bile acid 75-SeHCAT compared to the controls. Highest retention values were found in animals with anisoperistaltic loops (t1/2 = 98.6 h). Isoperistaltic loops showed uniform values independently of the length of the Roux-limb (t1/2 = 59.8 h resp. 59.3 h). Differences to the controls (t1/2 = 42.6 h) were highly significant (p less than 0.001). In the 99m-Tc-HIDA hepatic excretion into the connected small bowel was normal in all groups. But in rats with biliary anastomoses a marked stasis of the 99m-Tc-HIDA in the Roux-Y loop was apparent. Bowel transit time tested by 51-Cr-EDTA showed comparable results in all groups without significant differences. The results demonstrate an increased bile acid retention in Roux-Y biliary anastomoses. An alteration of the enterohepatic circulation due to stasis in the Roux-Y limb seems to be the underlying mechanism.