Adding Malabsorption for Failed Gastric Bypass
Condition: Clinically Severe Obesity; Obesity Recidivism; Inadequate Initial Weight Loss; Poor Weight Loss; Persistent Obesity; Refractory Obesity; Intractable Obesity
MeSH terms: Malabsorption Syndromes; Obesity; Obesity, Morbid; Body Weight; Weight Loss
Study type: Observational

Summary: 
      The main aim of this study is to analyze and report the preliminary and intermediate term
      outcomes after laparoscopic revision Roux-en-Y gastric bypass surgery for weight recidivism.
      The foremost outcome measurements are 1) Fat loss mainly measured as weight loss and
      expressed as trends in BMI, %EWL, and/or %EBL; 2) Trend in Comorbidity status; and 3) Patient
      satisfaction and Health-Related Quality of Life "HR-QoL" measured by a standardized,
      non-validated subjective satisfaction questionnaire and the validated, disease-specific,
      Moorehead-Ardelt II QoL questionnaires, respectively; 4) Morbidity & Mortality including
      nutritional status and metabolic complications.

      Consequently, secondary objectives of this study are 1) to assess failure rate defined as
      percentage of excess weight loss < 50% , lowest BMI >35 for morbidly obese (MO) or >40 for
      superobese (SO), and/or lack of resolution/improvement of major comorbidities at the point in
      time when assessing preliminary and intermediate results after the surgery under analysis. 2)
      To evaluate the metabolic and nutritional status by measurements of particular clinical and
      biochemical parameters.

      This research is in line with the most current provocative new ideas and recent high impact
      publications. To the best of our knowledge, this is the very first outcome study of
      revisional malabsorptive distal gastric bypass surgery by laparoscopy with diverse revisional
      strategies such as revisional gastroplasty, revisional Fobi-Capella, revisional Adjustable
      Gastric Band, conversion to distal, and conversion to very, very long limb gastric bypass.
      Previously, several studies have addressed conversion to malabsorptive gastric bypass after a
      failed primary proximal gastric bypass but none has addressed the failed distal gastric
      bypass nor the adequate balance between increasing restriction and malabsorption for
      decreasing the risk of protein-calorie malnutrition.
    

Detailed description: 
      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.
    

Observational model: Cohort
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Patients who had either clinically severe obesity (morbid obesity, MO, or super obesity,
        SO) underwent a primary Roux-en-Y gastric bypass. The ones that were subsequently revised
        ending up with an optimized malabsorptive distal gastric bypass were identified from our
        prospectively maintained bariatric database and included in this study. Specific metabolic
        and nutritional complications after RYGB surgery were defined according to standard
        definitions based on signs, symptoms, and laboratory measurements.
      
Keywords: Failed gastric bypass; Malabsorptive distal gastric bypass; Distal gastric bypass; Malabsorptive gastric bypass; Adding malabsorption; Increasing malabsorption; Re-operative bariatric surgery; Revisional bariatric surgery; Revisional gastric bypass; Reoperations; Conversions