In this group of bariatric bypass procedures for weight loss acceleration, the digestive system organs' alterations are more involved. There is more ‘surgery' involved and with more things being performed during a bariatric surgery, there is a greater degree of difficulty. These types of bariatric surgeries can be both restrictive and malabsorptive type bypass procedures. In these bariatric surgeries, digestive juices from the liver and pancreas can be diverted from their normal emptying points to an area of the distal small intestine near the entrance to the large intestine. The effect of this type of bariatric bypass procedure results in the food meal entering the stomach, rapidly transverses the distal small intestine (where absorption of nutrients primarily occurs), and is then delivered to the large intestine. This results in marked malabsorption of nutrients with subsequent marked weight loss (up to 80% of excess body weight). Since there is marked malabsorption of essential nutrients, the probability of vitamin, mineral, and protein-calorie malnutrition can be significant.
Biliopancreatic Diversion with Duodenal Switch (BPDDS).
In 1988, Hess, using a combination of Scopinaro's BPD and the duodenal switch described by DeMeester in 1987, developed a hybrid operation with the advantages of the BPD but without some of the associated problems.
This particular bariatric weight loss surgery for the treatment of morbid obesity is very complex to describe in non medical terms and is best left for the bariatric surgeon to explain to an interested patient during a private consultation. A simplified explanation is that a larger portion of the stomach is left intact, including the pyloric valve that regulates the release of contents from the stomach into the small intestine. The duodenum (which normally accepts the stomach contents) is stapled closed near the pyloric valve and small intestine divided as well. The portion of the small intestine connected to large intestine is attached to the short duodenal segment next to the stomach. The remaining segment of the duodenum connected to the pancreas and gallbladder is attached to this limb closer to the large intestine. Where contents from these two segments mix is called the common channel, which dumps into the large intestine.
BPD and its variants are the most major weight loss procedures performed for obesity and it follows that prospective patients who wish to consider BPD should seek out experienced surgeons with life-long follow up programs.
Click to see picture of biliopancreatic diversion with duodenal switch surgery for weight loss.