Adding Malabsorption for Failed Gastric Bypass

Since 1998, there has been a substantially progressive increase in bariatric surgery. In 2005, the American Society of Metabolic and Bariatric Surgery (ASMBS) reported that 81% of bariatric procedures were approached laparoscopically. 205,000 people, in 2007, had bariatric surgery in the United States from which approximately 80% of these were Gastric Bypass. Moreover, there is a mismatch between eligibility and receipt of bariatric surgery with just less than 1% of the eligible population being treated for morbid obesity through bariatric surgery. Along with the increasing number of elective primary weight loss procedures, up to 20% of post RYGB patients cannot sustain their weight loss beyond 2 to 3 years after the primary bariatric procedure11. Thus, revisional surgery for poor weight loss and re-operations for technical or mechanical complications will rise in a parallel manner. RYGB is consistently considered the revisional procedure of choice for failed restrictive procedures.

At present there are three broad categories of bariatric procedures according to its mechanism of action: 1) purely restrictive, 2) primarily restrictive with some malabsorption, and 3) primarily malabsorptive with some restriction. Modern standard bariatric procedures recognized by the American Society for Metabolic and Bariatric Surgery "ASMBS" include the following 1) adjustable gastric band, 2) sleeve gastrectomy, 3) gastric bypass, 4) biliopancreatic diversion, and 5) duodenal switch.

In general, there is a lack of long-term (5-10 years) and very long-term (> 10 years) outcome studies for modern bariatric surgery that would allow us to better define the role of each one of these procedures, especially after the advent of the laparoscopic approach.

In an animal model, diet induced obese animals exhibiting metabolic syndrome underwent Roux-en-Y gastric bypass with highly reproducible surgical outcomes as well as biochemical and energetic homeostatic abnormalities similar to post-RYGB findings in humans. Weight regain occurs in approximately 20% of patients after two to three years after RYGB. It seems that the weight-loss-promoting effects of chronically elevated plasma PYY concentrations dominate the weight-gain-promoting effects of lowered plasma leptin concentrations, with the relative plasma PYY: leptin concentration ratio determining whether weight loss will be sustained or regained.

Several studies have compared different Roux limb lengths in primary bariatric surgery. It seems to be that long limb RYGB (150cm), especially in patients with BMI > 50 kg/m2, confers at least better short-term weight loss without nutritional consequences. Conversely, other investigators have not found any clinically significant difference in weight loss with increasing Roux limb lengths, especially in patients with BMI < 50 kg/m2 23-26. The following are the main investigators that have increased the malabsorptive component of the failed proximal gastric bypass as a revisional strategy:

1. Torres JC in 1991 was the first to propose this strategy with a cohort of 140 patients followed for 5 years (90.5% follow-up rate). Analyzed traditional outcome measures were early (2.1%) and late (27%) morbidity including protein-calorie malnutrition (7%); %EWL at 1,2,3,4,and 5 years were 89.5%, 91%, 87%, 82.5%, 82.5%, respectively; and re-operations.

2. Fox SR and Oh KH et al in 1996 reported 10 failed proximal gastric bypass patients undergoing distal gastric bypass from an diverse group of failed primary surgeries (n=80) followed for 3 years with a 92.5% follow-up rate. Reported traditional outcome measures were early (39%) and late (84%) morbidity; %EWL at 1,2,&3 years was 83%, 89%and 94%, respectively; high satisfaction was also reported.

3. Sugerman et al in 1997 published their outcomes with 27 patients. Five patients were converted to a malabsortive distal gastric bypass with a 50cm common channel which required a second revision for malnutrition and two died. 22 patients were revised to a 150cm common channel; three patients required a second revision for malnutrition but %EWL went from 30% to 61% at 1 year and 69% at 5 years. They concluded that a 50cm common channel had an unacceptable morbidity and mortality.

4. Fobi et al in 2000 presented his results of 65 patients after mostly failed primary Fobi pouch operation. 15 patients developed protein calorie malnutrition requiring supplemental nutrition and 6 required further revision.

5. The 2001 Sapala´s et al partial outcome analysis on 303 varied revisionary micropouch gastric bypass procedures with a 200cm Roux limb, 150cm biliopancreatic limb and >200cm common channel. %EWL during 3 years is similar to the primary procedure (68.6%, 76.6%, and 72.3%). However no subset analysis is performed.

6. Pareja et al analysis of 41 patients, undergoing diverse distal malabsorptive techniques, included 32 revisionary procedures after primary Fobi-Capella gastric bypass. At 11, 16, and 19 months of mean follow-up, %EWL for the Scopinaro-style, Brolin, and Fobi revisionary gastric bypasses were 69.7%, 65.0%, 74.8%, respectively. Failure and success rates according to Biron et al. are provided but no other subgroup analysis is provided.

7. Brolin et al on 2007 reported 47 out of 54 patients undergoing revision for failed primary bariatric surgery had a very, very long limb gastric bypass with a 75cm to 100cm common channel and a 15cm to 25cm biliopancreatic limb. 7.4% (n=4) developed protein-calorie malnutrition from which one required 6 weeks of TPN, two elongation of the common channel (150cm) and one reversal after a prolonged hiatus returning with severe metabolic complications. 47.9% of the series lost at least 50% EWL at 1 year. There was no difference between those with primary failed restrictive vs. primary failed gastric bypass patients.

8. Sarr et al on 2007 states that "patients with anatomically intact, non-malabsorptive RYGB when converted to a malabsortive distal RYGB, good results are not common".

To the best of our knowledge and after extensive literature search, there is no outcome study employing a laparoscopic approach for revisional malabsorptive distal Roux-en-Y gastric bypass specially increasing the restrictive component in a failed primary malabsorptive distal type of gastric bypass. Thus, we decided to analyze our own series including the learning curve and diverse revisional techniques in this unique subset of patients: 1) revision gastroplasty; 2) Fobi-Capella (static band); 3) Adjustable gastric band; 4) Conversion to either modality of malabsorptive distal gastric bypass, very, very long limb or distal.

Summarizing, there is lack of very-long term outcomes after bariatric surgery and standardization of gastric bypass surgery. The treatment of inadequate weight loss or weight recidivism after Roux-en-Y gastric bypass (RYGB) remains refractory to medical treatment. Failure rates have been reported up to 20% and 35% for the morbidly obese and super obese, respectively at 2 to 3 years after surgery. The indication for further surgical intervention remains controversial, as does what type of procedure to recommend. Furthermore, there is no standardization of the limb lengths, pouch size or the use of prosthetic reinforcement. Therefore the approach to these patients must be as individualized as their original operations. We analyze our experience with the laparoscopic approach to these complex and challenging patients.