The procedure involves
- distal gastrectomy, with the formation of a gastric pouch
- gastroenterostomy, with the formation of a ~250 cm Roux limb (normal small bowel is ~550 cm long)
- anastomosis of the biliopancreatic limb to the Roux limb ~50 cm proximal to the ileocecal valve
The bypass is designed to have a mixture of restrictive and malabsorption effects.
Postgastrectomy syndrome led to the development of a duodenal switch variant. In this variant, the stomach is restricted along the greater curvature (like a sleeve gastrectomy), and the shortened Roux limb is attached end-to-end to the proximal duodenum. The biliopancreatic limb is attached similarly to the normal biliopancreatic diversion.
Treatment and prognosis
The biliopancreatic diversion has been reported to result in 70% of long term weight loss in >90% of patients 2. The duodenal switch variant may be even more effective 3. These procedures may occasionally be used when other more conservative bariatric procedures have failed.
Although the procedure avoids the bypass enteritis of jejunoileal bypass (with an associated risk of hepatic failure), it does have a number of side effects, including
- risk of nutritional deficiency: calcium, fat-soluble vitamins, and protein
postgastrectomy syndrome: marginal ulcers and dumping syndrome
- decreased with duodenal switch
- bowel obstruction, internal hernia, anastomotic leak
- 1. Moshiri M, Osman S, Robinson TJ et-al. Evolution of bariatric surgery: a historical perspective. AJR Am J Roentgenol. 2013;201 (1): W40-8. doi:10.2214/AJR.12.10131 - Pubmed citation
- 2. Scopinaro N. Thirty-five years of biliopancreatic diversion: notes on gastrointestinal physiology to complete the published information useful for a better understanding and clinical use of the operation. Obes Surg. 2012;22 (3): 427-32. doi:10.1007/s11695-011-0554-3 - Pubmed citation
- 3. Carucci LR, Turner MA. Imaging following bariatric procedures: Roux-en-Y gastric bypass, gastric sleeve, and biliopancreatic diversion. Abdom Imaging. 2012;37 (5): 697-711. doi:10.1007/s00261-012-9860-z - Pubmed citation