The Duodenal Switch or Bilio-pancreatic Diversion (BPD-DS) procedure uses a sleeve gastrectomy combined with an intestinal bypass to induce weight loss.

In this procedure 60-70% of the upper part of the stomach is removed, creating a banana-shaped sleeve. The pylorus (the opening from the stomach into the duodenum) stays intact rather than being bypassed.

The small intestine is divided at the duodenum (the first part of the small intestine) and connected to the illeum (the bottom third of the small intestine). The jejunum (the part of the small intestine between the duodenum and ileum) is bypassed.

Food is rerouted into the ileum, bypassing the jejunum. The jejunum (biliopancreatic limb) joins the ileum forming a connection in the shape of a “Y”.  Bile and enzymes that breakdown and absorb protein and fat can pass down the biliopancreatic limb and mix with the food in the ileum which then passes into the colon naturally. This procedure reduces the number of calories and nutrients absorbed, resulting in weight loss.