Division of the hepatic branch of the anterior vagus nerve in fundoplication: effects on gallbladder function

Abstract

Cutting the hepatic branch of the anterior vagus nerve makes laparoscopic fundoplication technically easier; however, there is little data about the effect of cutting the nerve on gallbladder function. One surgeon (MPä) preserved this nerve until March 2001 when he changed the technique. We investigated patients consecutively operated on before and after this date. A symptom questionnaire was returned by 59 patients, of whom 19 in both groups were successfully further investigated. The follow-up varied from 4 to 9 years postoperatively. The volume of the gallbladder was measured by ultrasonography before and after a fatty test meal. Alkaline phosphatase (ALP), alanine aminotransferase (ALAT), bilirubin, and amylase were determined from plasma. There was no difference in symptoms or use of antireflux medication between the groups. No difference was found in the levels of bilirubin, ALAT, or ALP. A mild elevation in plasma amylase was noted after nerve division (p = 0.041). The gallbladder ejection fraction did not differ between groups, but the fasting gallbladder volume was smaller when the nerve was cut (median 18.1 (range, 6-57.7) ml versus median 23.2 (range, 7.9-66.7) ml; p = 0.049). Both differences in plasma amylase and gallbladder fasting volume were clearer in male patients. Cutting the hepatic branch of the anterior vagus nerve during fundoplication may reduce the size of gallbladder, but it has no effect on the ejection fraction. No clinical significance has been noted to date. Prospective trials will be necessary to confirm these findings.