Internal Hernias After Laparoscopic Gastric Bypass
Condition: Internal Hernia; Mesocolic Hernia; Petersen´s Hernia; Jejunojejunostomy Hernia; Bowel Obstruction; Ischemic Bowel
MeSH terms: Intestinal Obstruction; Hernia; Internal Hernia; Hernia, Abdominal
Study type: Observational

Summary: 
      The main goal of this study is to describe the trends in the incidence rate of internal
      hernia presentation after different modifications of the mesenteric closure technique after
      primary laparoscopic Roux-en-Y gastric bypass (RYGB) surgery from 1997-2009.
    

Detailed description: 
      The main goal of this study is to describe and analyze the trends in the incidence rate of
      internal hernia presentation after different modifications of the mesenteric closure
      technique after Primary Laparoscopic RYGB Surgery from 1997 to 2009.

      Secondary study aims are to describe the following points 1. Clinical presentation, whether
      acute (small bowel obstruction), chronic (intermittent abdominal pain), or incidental finding
      -(asymptomatic); 2. Preoperative image studies. The percentage of patients that underwent
      preoperative CT/contrast studies as well as the percentage of patients that had positive,
      undetermined, and normal results; 3. Site of internal herniation including transverse
      mesocolon, jejunal mesentery, and Peterson's space as well as single vs. multiple internal
      hernias. This study along with the existing literature will allow us to formulate preliminary
      clinical recommendations.

      This research is in line with the most current provocative new ideas and recent high impact
      publications. Most literature points towards the antecolic routing of the Roux limb to
      decrease the incidence rate of internal hernia formation. However, with this study we will
      demonstrate the statistically and clinically significant decrement of internal hernia
      formation with the improvement of the closure technique with a retrocolic antegastric routing
      of the Roux limb.

      The epidemic of overweight and obesity in the United States of America along with its
      comorbidities continues to expand. Bariatric surgery has demonstrated to be the most
      effective and sustained method to control severe obesity and its comorbidities. For instance,
      type 2 diabetes mellitus was completely resolved in 76.8 percent, systemic arterial
      hypertension was resolved in 61.7 percent, dyslipidemia improved in 70 percent, and
      obstructive sleep apnea-hypopnea syndrome was resolved in 85.7 percent. Furthermore,
      bariatric surgery significantly increases life expectancy (89 percent) and decreases overall
      mortality (30 to 40 percent), particularly deaths from diabetes, heart disease, and cancer.
      Lastly, preliminary evidence about downstream savings associated with bariatric surgery
      offset the initial costs in 2 to 4 years.

      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
      percent of bariatric procedures were approached laparoscopically. 205,000 people, in 2007,
      had bariatric surgery in the United States from which approximately 80 percentage 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 surgery10. Along with the increasing number of elective primary
      weight loss procedures, up to 20 percent 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 reoperations 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.

      There are no multi center, randomized, double blinded control trials comparing the different
      standard bariatric procedures. Gastric bypass is the oldest available bariatric procedure;
      without any randomized controlled trials, it is considered the gold standard procedure in the
      United States.

      Incisional hernias occur at a higher incidence rate after open RYGB, approximately 20
      percent, whereas after laparoscopic Roux-en-Y gastric bypass "RYGB", the incidence rate is
      very low. Conversely, Internal hernia is a rare complication with the open approach whereas
      after laparoscopic RYGB the incidence rate has been reported somewhere between 0.2 to 8.6
      percent. The most accepted theory is due to decreased adhesion formation after laparoscopic
      surgery compared to open surgery.

      Other factors associated with a higher incidence of internal hernia formation after RYGB are
      1. childbearing age with the consequent pregnancy after RYGB, 2. Roux limb routing, 3.
      Closure of mesenteric and or mesocolic defects.

      Although there have been no randomized controlled trials comparing different techniques of
      laparoscopic RYGB, several authors have report lower rates after modifying their technique
      from a retrocolic to an antecolic approach. On the other hand, others support meticulous
      defect closure as the most important factor in reducing hernia formation.

      The method of fixation and mesenteric closure has evolved. Initially, as with the open
      approach, defects were not closed. Then, absorbable sutures were used which were changed for
      interrupted non-absorbable sutures. Lastly, continuous non-absorbable material for closing
      all defects was recommended by Sugerman.

      Summarizing, there is no high level of evidence for recommending the best strategy to
      decrease the incidence rate the potentially devastating complication of internal hernia after
      laparoscopic RYGB. After reviewing the literature the trend is toward lower rates of internal
      hernia formation with antecolic compared to retrocolic, and with defect closure compared to
      nonclosure. There is great variation in the incidence rate among the reported series
      reflecting incomplete follow-up and other factors may affect outcomes. With this study, we
      will analyze the trends in the incidence rate of internal hernia formation among different
      subgroups in our consecutive series of more than 7,500 laparoscopic retrocolic RYGB with a
      hand-sawn gastrojejunostomy. With this consecutive series, we will confirm reports of small
      series that meticulous closure technique of mesocolic/mesenteric defects with continuous
      nonabsorbable material clinically and statistically decreases the formation rate of internal
      hernias after laparoscopic gastric bypass.
    

Observational model: Cohort
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Patients presenting with internal hernia after different modifications of the mesenteric
        closure technique after Primary Laparoscopic RYGB surgery from 1997-2009.
      
Keywords: Internal hernia; Mesocolic hernia; Petersen´s hernia; Jejunojejunostomy hernia; Bowel obstruction; Ischemic bowel; Complication after gastric bypass; Re-operative bariatric surgery; Chronic pain after gastric bypass