The Effect of Vagotomy on Gallbladder Function and Bile Composition in Man

Abstract

Vagotomy and gastric surgery have been implicated in gallstone formation, although the association remains unproven. Gallbladder function was investigated in 11 patients with a pyloroplasty and truncal vagotomy, 5 with a subtotal gastrectomy and 16 healthy controls. Gallbladder filling and emptying in response to cholecystokinin (CCK 0.02 U/kg min), when quantitated by 99m-Tc-N-(2,6-dimethylphenylcarbomoylmethyl) iminodiacetic acid cholescintigraphy, did not show any differences between the control and the surgical groups. In each group, > 70% of hepatic activity partitioned into the gallbladder rather than the duodenum, filling the gallbladder at 2.1%/min. Gallbladder emptying began 5 min after initiating the CCK infusion and ejected half its contents during the next 12 min. Biliary lipid composition was determined in 20 patients who underwent elective pyloroplasty and vagotomy for duodenal ulcer disease. Gallbladder bile collected at surgery was compared in bile-rich duodenal fluid aspirated 8 mo. after recovery from surgery. Cholesterol saturation decreased significantly (P < 0.05) both in terms of the relative cholesterol content (6.9% .fwdarw. 5.2%) and the lithogenic index (1.24 .fwdarw. 0.84). To determine if a selective increase in one of the conjugated bile salts could explain this improvement, bile salt composition was analyzed by high pressure liquid chromatography in 8 patients and showed no change after surgery. Vagotomy does not adversely affect gallbladder function, but instead improves cholesterol solubility.