The Restrictive Component
The BPD/DS combines restrictive and malabsorptive elements to achieve and maintain the best reported long-term percentage of excess weight loss among modern weight-loss surgery procedures.
The BPD/DS procedure includes a partial gastrectomy, which reduces the stomach along the greater curvature, effectively restricting its capacity while maintaining its normal functionality.
Unlike the unmodified BPD and RNY, which both employ a gastric "pouch" and bypass the pyloric valve, the DS procedure keeps the pyloric valve intact. This eliminates the possibility of dumping syndrome, marginal ulcers, stoma closures and blockages, all of which can occur after other gastric bypass procedures.
In addition, unlike the unmodified BPD and RNY procedures, the DS procedure keeps a portion of the duodenum in the food stream. The preservation of the pylorus/duodenum pathway means that food is digested normally (to an optimally absorbable consistency) in the stomach before being excreted by the pylorus into the small intestine. As a result, the DS procedure enables more-normal absorption of many nutrients (including protein, calcium, iron and vitamin B12) than is seen after other gastric bypass procedures.
The Malabsorptive Component
The malabsorptive component of the BPD/DS procedure rearranges the small intestine to separate the flow of food from the flow of bile and pancreatic juices. This inhibits the absorption of calories and some nutrients. Further down the digestive tract, these divided intestinal paths are rejoined; food and digestive juices begin to mix, and limited fat absorption occurs in the common tract as the food continues on its path toward the large intestine.
For more detailed procedure information, see Dr. Hess' patient brochure. For other detailed descriptions and illustrations, see the More Information page for links to surgeon's websites and more.
The standalone Duodenal Switch procedure (without the accompanying gastric bypass as used in weight-loss surgery) was originally devised by Tom R. DeMeester, M.D. to treat bile gastritis, a condition in which the stomach and esophagus are burned by bile. In 1988, Dr. Douglas Hess of Bowling Green, Ohio, was the first surgeon to combine the DS with the Biliopancreatic Diversion (BPD) form of obesity surgery. This hybrid procedure, known as the Biliopancreatic Diversion with Duodenal Switch (or the Distal Gastric Bypass with Duodenal Switch), solves many nutritional problems associated with other forms of WLS, and allows a magnificent eating quality when compared to other WLS procedures.