Bile composition and bile acid pool size. Comparison after truncal, selective, and highly selective vagotomy

We studied biliary lipid composition and bile acid pool size in 29 patients surgically treated for duodenal ulcer. Fourteen were examined both before and after surgery, the rest postsurgically only. They were divided into three groups according to type of vagotomy. With duodenal fluid obtained via nasogastric tube, we determined bile acid pool size, bile concentrations, and lithogenic index. We found no significant differences in bile composition and bile acid pool size among the three types of vagotomy, postsurgically. However, patients studied before surgery, compared with the entire post-vagotomy group, had a significant increase in relative cholesterol content and lithogenic index, most pronounced in the truncal vagotomy group. Bile acid pool size was also increased postsurgically. Vagotomy may predispose to gallstone development by increasing the bile's relative cholesterol concentration and thus the lithogenic index. However, the slightly expanded bile acid pool size may improve cholesterol solubility in certain patients.