Determinants of Fat Malabsorption After Roux-en-Y Gastric Bypass
Condition: Severe Obesity
MeSH terms: Obesity; Obesity, Morbid
Study type: Interventional

Summary: 
      The purpose of this study is to determine whether or not the length of the biliopancreatic
      limb of the Roux-en-Y anastamosis plays a critical role in the development of malabsorption
      after gastric bypass for treatment of severe obesity.
    

Detailed description: 
      Successful surgical treatment of severe obesity by RYGB is believed to require a procedure
      that (a) restricts the consumption of combustible food energy, and (b) reduces the intestinal
      absorption of food energy that is consumed. However, with RYGB operations that are currently
      employed, many patients do not develop the malabsorption they presumably require to produce
      good long term control of their body weight. It is important to find a way to do RYGB surgery
      in a way that consistently produces a moderate degree of fat malabsorption.

      Patients who are scheduled to receive a RYGB for treatment of severe obesity will be randomly
      assigned to receive 2 variations of the standard operation. The stomach and duodenal bypass,
      and the creation of a small gastric pouch will be exactly the same for all patients. There
      will be differences in the two jejunal limbs which create the Roux-en-Y anastomosis. In
      Procedure A, the Roux limb length will be 150 cm, and the biliopancreatic limb will contain
      40 cm of jejunum. In Procedure B, the Roux limb length will be 110 cm and the biliopancreatic
      limb will contain 80 cm of jejunum. The total length of jejunum in both limbs is 190 cm in
      both procedures. Thus, the only difference between procedures A and B is that B procedure has
      a larger percentage of jejunum in the biliopancreatic limb (80/190=42%) than procedure A
      (40/190 = 21%). A total of 20 patients will be studied, 10 with each procedure. Before and
      after RYGB, the patients will be studied in a clinical research laboratory. Dietary intake
      and intestinal absorption of fat, protein, carbohydrate and combustible energy will be
      measured by metabolic balance techniques for 72 hours. We hypothesize that fat malabsorption
      after bypass will be greater and more consistent in patients who receive the longer
      biliopancreatic limb than in the patients who receive the longer Roux limb.
    

Intervention name(s): RYGB for surgical treatment of severe obesity
Intervention type(s): Procedure
Intervention description(s): Twenty severely obese patients who have been scheduled to receive long limb RYGB will be enrolled in the study. By randomization, 10 patients will have a biliopancreatic limb that includes 40 cm of jejunum and a Roux limb that contains 150 cm of jejunum. The other 10 patients will receive a biliopancreatic limb that contains 75 cm of jejunum and a Roux limb of 115 cm.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: Malabsorption after RYGB; Fat Malabsorption and maldigestion; Obesity surgery; Bariatric surgery