Nicola Scopinaro developed biliopancreatic diversion. Duodenal switch is a variant that keeps the pylorus and a sleeve stomach, then connects the duodenum to a long alimentary limb with a measured common channel. Food and digestive juices meet late. You absorb fewer calories. Gut hormones change hunger and blood sugar.
DS preserves the pylorus but bypasses a substantial length of intestine. This does not protect against iron, B12 or other deficiencies. Protein malnutrition and vitamin deficiencies require prevention and lifelong monitoring. The sleeve component can cause or worsen reflux; DS is not a reflux treatment.
What it is good at
- Substantial weight and metabolic effects in appropriately selected patients
- Improvement or remission of type 2 diabetes; recurrence remains possible
- Highest average excess-weight loss among the three core operations
What you live with
- Loose or oily stools, gas, and an individualized protein target generally higher than after sleeve alone
- ADEK vitamins, calcium, iron, copper/zinc balance, frequent labs
- Not the first choice in Crohn’s disease or decompensated cirrhosis
- SADI is a related but different construction; converting SADI to a true DS is a revision, not a rename
The ability to meet protein needs, obtain supplements and complete follow-up is central to suitability. Nutritional problems may require medical treatment or revision. See How we choose and After surgery.
Further reading: ASMBS: bariatric surgery procedures. Procedure selection and follow-up are individualized.