Gastric pouch acid secretion in response to physiologic digestive function

Objectives. To evaluate acid secretion and histologic features of the gastr ic segment used for bladder replacement in bladder cancer. Methods. Nine patients were investigated a mean of 36 months after gastric pouch surgery with modified shamfeeding and feeding. We determined urinary acidity, urinary pH, serum gastrin, and serum pancreatic polypeptide values and tried to find a relationship between feeding and acid secretion in the gastric pouch. In 6 patients, biopsy and histopathologic examination were performed. Results. In 8 patients, urinary acidity increased after feeding following t he rise of gastrin; in 1 patient no increase of gastrin or acidity was obse rved. In 7 patients, urinary acidity did not change after modified shamfeed ing, indicating vagal denervation after surgery. This group showed a minima l urinary pH of above 4 after feeding. On the other hand, in 2 patients an increased acid secretion was observed after modified shamfeeding, indicatin g the possible presence of residual vagal innervation. In this group, the a cid secretion in the pouch was higher, reaching the minimal pH level earlie r after feeding. Histopathologic examination showed no major structural cha nges of gastric mucosa. Conclusions. Most patients are vagally denervated after gastric pouch surge ry, and the gastric segment continues its original gastrointestinal functio n by a hormonal pathway. Our data indicate, however, that in some patients, the gastric pouch keeps a residual vagal innervation. We therefore suggest that nerve fibers present in the blood supply of the gastric segment be in terrupted to avoid the complications associated with increased acid secreti on of the gastric pouch. (C) 1999, Elsevier Science Inc.