Surgical Options: Malabsorptive and Combination Procedures
Malabsorptive and combination (restrictive-malabsorptive) operations are the most common gastrointestinal surgeries for weight loss. They restrict food intake, by making the stomach smaller, and also the amount of calories and nutrients the body absorbs. Malabsorptive operations for weight loss include Roux-en-Y gastric bypass (RGB) and biliopancreatic diversion (BPD).
Reasons for the Procedure
The surgery promotes weight loss by restricting food intake or by interrupting the digestive process. But even after surgery, the best long-term results are achieved by eating appropriately and participating in a regular physical activity program.
Malabsorptive operations such as the Roux-en-Y gastric bypass and the biliopancreatic diversion are more complicated procedures that work in two main ways. First, the size of the stomach is reduced so that it will only accommodate a few ounces of food. Second, food is rerouted bypassing a portion of small intestines. This results in less food (and thus calories) being absorbed when eating.
Malabsorptive operations such as the Roux-en-Y gastric bypass and the biliopancreatic diversion combine the creation of small stomach pouches to restrict food intake and the construction of bypasses of the duodenum and other segments of the small intestine to reduce nutrient absorption.
Malabsorptive operations produce more weight loss than restrictive operations, and are more effective in reversing the health problems associated with severe obesity, but require more supplements and careful life-long follow up care.1, 2, 3 Patients who have malabsorptive operations combined with lifestyle modification generally lose two-thirds of their excess weight within two years. Most reports indicate that patients lose 66 to 80 percent of excess body weight following the gastric bypass procedure.
1 Scopinaro N., Biliopancreatic diversion: mechanisms of action and long-term results.Obesity Surgery 2006 Jun;16(6):683-9.
2 Marceau P, Hould FS, Lebel S, Marceau S, Biron S. Malabsorptive obesity surgery. Surg Clin North Amer 2001 Oct; 81(5):1113-27.
3 Buchwald H, Avidor Y, Braunwald E, et al. Bariatric surgery: a systematic review and meta-analysis. JAMA 2004 Oct; 292(14):1724-37.