Ulcerogenesis in Surgery for Obesity

Edward Eaton Mason MD

NBSR Newsletter Winter 1995 Volume 10, Number 4

Important relationships exist between the body of the stomach, antrum, and duodenum that protect both duodenal and stomal mucosa from ulceration. Operative disturbance of these relationships may lead to stomal and/or duodenal ulcers unless some counteracting measure(s) are taken. Devine(1) in Melbourn, Australia used antral exclusion in the treatment of large duodenal ulcers in 1928. Antral exclusion rapidly gained a world-wide reputation for producing stomal ulcers. Before gastric bypass was used in man, the operation was studied in laboratory animals to make certain that stomal ulcers would not result.(2) Gastric bypass included enough acid secreting mucosa to suppress gastrin secretion,(3) which was the cause of stomal ulcers after the antral exclusion operation of Devine.

Scopinaro's biliopancreatic diversion (BPD),(4) for treating obesity, is a Mann-Williamson(5) preparation in which bile and pancreatic juices are diverted into the ileum. Scopinaro includes resection of the distal stomach which removes both the gastrin secreting antrum and a portion of the acid secreting parietal cell mass. Others are using BPD without removing the excluded stomach. An interesting modification of Scopinaro's biliopancreatic diversion is now in use.(6) This operation uses two measures to reduce the risk of stomal ulceration. One is DeMeester's duodenal switch(7) and the other is Wangensteens's sleeve resection of most of the parietal cell mass.(8)

DeMeester demonstrated that when the stomach was separated from the duodenum, the stomal ulceration rate was 86% after anastomosis of duodenum to ileum and 100% if anastomosed to jejunum. Acid secretory inhibition, from acid washing over the duodenum, no longer occurred. DeMeester then showed that if the duodenum was divided just above the entry of the bile and pancreatic ducts, the risk of stomal ulceration was reduced to 29% and 10% respectively. Acid secretory inhibition was preserved by maintaining continuity between the stomach and the first part of the duodenum.

A number of surgeons have combined a modification of vertical banded gastroplasty with a Roux-en-Y gastric resection, using varying lengths of intestinal bypass in the limbs of the intestinal reconstruction. To the extent that the bile and pancreatic juice are shunted into lower reaches of the small bowel, this simulates a Mann-Williamson preparation. When excessive acid secretion is added to the equation, as in bypass operations for obesity, the site of ulceration depends in part upon where the most acid leaves the stomach.(9) An extensive gastric exclusion protects the stoma, but at the risk of duodenal ulceration. A large pouch increases the risk of stomal ulceration while protecting the duodenum. It must be remembered, however, that if the exclusion is antral without sufficient parietal cell mass, uninhibited gastrin secretion causes stomal ulceration.

When direct communications develop between the pouch and the excluded stomach following staple line disruption after gastric bypass, this becomes an ulcerogenic preparation requiring operative correction.(10) If the pouch is too large, stomal ulcers are seen. If most of the stomach is excluded, duodenal ulceration may occur.

Surgeons should avoid ulcerogenic anatomy in their efforts to reduce all patients to a normal weight. Much can be accomplished by operations that restrict food intake but do not interfere with the normal relationships between the acid secreting portion of the stomach, the gastrin secreting antrum, and the duodenum. It is interesting to observe the repetition of learning that continues in the use of stomach operations. Operations to reduce acid have been replaced by treatment of infection with Helicobacter pylori.

Stomach operations for obesity were originally modifications of operations designed for the treatment of acid peptic disease. Now, operations for obesity performed on the stomach must be designed to avoid the production of acid peptic disease. Gastric surgery for ulcer has been lost, but the lessons learned remain of great value.

History does repeat. It is possible that operations on the stomach for obesity will also be replaced by specific medical treatment as we learn more about the etiology (DNA) of severe obesity. In the meantime, severe obesity continues to be morbid and lethal and operations remain the only effective means of treatment. Even a small increase in risk of ulcer is to be avoided because of the long life that most of these patients have. We are now seeing occasional duodenal bleeding and stomal ulcers in patients who had a gastric bypass many years ago. Severe bleeding leads to operations that in turn become complicated, or the bleeding may even be lethal before a diagnosis and appropriate treatment can be applied. Surgeons today must avoid the production of peptic ulcer when they are treating obesity.

It took two million years of DNA evolution to assemble the upper gastrointestinal tract of humans and related mammals. As time goes on and we examine the evidence through follow-up, we find that "keep it simple surgeon" (KISS) is usually best. Let's dedicate our efforts toward a better, and international N(I)BSR. The practical way to do this is to assemble lists of consecutive patients who are five, ten, etc. years beyond operation and find out what really happened. This is doable because it can be done one patient at a time, as we find and devote a little of our time to following these patients long term. It is nature's way. It must be the surgeon's way to evolve better methods of treating the obese. Nule nocere for now and for each patient's lifetime.

1. Devine, HB. Gastric exclusion. SURGERY GYNECOLOGY AND OBSTETRICS. 1928, 47:239-243.

2. Mason EE, Ito C. Gastric bypass. SURGICAL CLINICS OF NORTH AMERICA. 1967; 47: 1345-1351.