Biliopancreatic Diversion with Duodenal Switch
This procedure was the forerunner of the gastric sleeve, and it involves both a sleeve gastrectomy as well as an intestinal bypass. It is the most complex bariatric procedure that is currently performed, but it has been offered by Meridian Surgical since 2005.
It has a restrictive component by giving patients a sleeve gastrectomy, and it has a significant malabsorptive component with the intestinal bypass. The stomach is larger than with the gastric bypass, so patients are not quite as limited with eating very small portions, but because it provides more malabsorption than the gastric bypass, patients lose more weight with this procedure than any other bariatric procedure currently in use. The digestive enzymes produced by the liver and pancreas do not mix with the food until they have passed through most of the small intestine, and so most fat calories are not absorbed. This does mean that patients have looser stools, and most patients with a duodenal switch will have several unformed stools per day. Diarrhea is possible, but it can usually be avoided by healthy food choices. The duodenal switch provides the most improvement or even cure of type 2 diabetes (adult-onset diabetes). It is essential that patients take vitamins for the rest of their life after a duodenal switch.
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