A duodenal switch is a variation of biliopancreatic diversion and is similar to a vertical sleeve gastrectomy, in the fact that it separates 70%-80% of the left side of the stomach in order to create a small pouch. However, duodenal switch keeps the pyloric valve intact, which helps prevent dumping syndrome.
In this procedure, the small intestine is rerouted to separate it from the pathway that carries bile from the liver. Before the food and bile goes into the large intestine, it meets in a common channel (about 18-24 inches long) that allows the food to be digested. This process allows only 20% fat absorption and reduced calorie absorption, as it takes a shorter time to reach the large intestine.
About 20,000 patients undergo duodenal switch procedures in the United States each year, according to the Consumer Guide to Bariatric Surgery. The procedure takes about 3-4 hours. Only about 50 doctors worldwide perform this procedure and it is still considered investigatory, as the long-term effects of malasorption are not known. For this reason, insurance may not cover any portion of the costs. The average cost of DS is about $20,000 and the morality rate is about 1%, according to the Laparoscopic Associates of San Francisco.