Mini-Gastric Bypass Surgery

Mini-Gastric Bypass is Becoming a Prevailing Bariatric Procedure

The mini-gastric one-anastomosis bypass has gained popularity during the past five years. This bariatric procedure is a safe, effective, revisible and surgically simple with less chance of leak.

Developed by Dr. Robert Rutledge in the United States in 1997, the mini-gastric one-anastomosis bypass (MGB) is a bariatric operation that is safe, effective and fast. In the past 5 years the MGB has taken a slow turn in popularity increasing steadily. Led by Drs. Rutledge and Jean-Marc Chevallier (the French bariatric society President – SOFCO) an international MGB conference with 55 world experts was held in October 2012. Overwhelming international requests were reason enough to have a second conference in Paris in October 2013. This conference brought together 35 MGB surgeons from 13 countries to learn and educate on the procedure. Prof. Pradeep Chowbey (the immediate past president of the International Federation for the Surgery of Obesity was the Chair for the conference. Prof. Chobey is considered to be the father of bariatric and laparoscopic surgery in India. Due to the reports of excellent results, the surgeries are becoming more popular.

There was reported experience by the attendees of the MGB consensus in other bariatric operations such as Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG) and gastric banding (GB).

Technique

There are two components to the laparoscopic operation (Figure 1) starting with a restrictive lesser-curvature gastric pouch and then a 200cm or longer jejunal bypass containing an antecolic gastro-jejunostoy (GJ) anastomosis, both leading to at malasborption that is substantial.

Diagrammatic representation of the MGB (by Robert Rutledge)
Creation of Gastric Pouch

At the junction of the body and the atrum, the lesser curvature of the stomach is identified. At first the stomach is stapler-divided to the lesser curvature, distal to the crow’s foot. Passed by the anesthetist is a 28-40fr bougie followed by the stomach being stapler-divided parallel and upward to the lesser curvature. The surgeon divides the stomach lateral to the angle of His with approach to the gastro-esophageal (GE) junction. Unlike in the SG operation the cardia in the MGB is avoided and not dissected.

Creation of a 200-cm Malabsorptive Jejunal Bypass

To identify the ligament of Treitz the focus is turned to the left gutter and the omentum is retracted medially and run to ~200 cm distal to Treitz’ ligament is the bowel. The distal tip of the gastric sleeve is anastomosed antiecolic end-to-side to the jejunum.

During the surgery issue such as hiatal hernias are left untouched. It is typical for MGB to be effective at improving GE reflux disease (GERD) believed to be because of the traction which the GJ anastomosis gives the gastric pouch. This resolves the patient’s obesity and reduces the cardia within the abdomen. There is little apparent dilation of the MGB because there is no narrowing of the outlet by a stoma or pylorus.

Modifications of the Techniques

The length of the bypass might vary depending on the MGB surgeon conducting the procedure. Those patients that are very obese or that are very tall might have a GJ performed >250 cm distal to Treitz’ ligament. In some cases such as Tacchino’s group from Italy has performed >600 MGBs. Some have reported that leaving a larger gastric pouch and creating a GJ 300cm that is proximal to the ileocecal valve is useful. The majority of surgeons are in agreement that the GJ needs to be at least 200-300 cm proximal to the ileocecal valve in order to provide adequate nutrition to the patient.

Caballero and Cabrajo were presented by Flores from Mexico. This is the process where an antireflux valve is created on the afferent side of the GJ then sutures are added between the sleeve and afferent limb, inhibiting reflux. Through surveys of the attendees of the event it has shown that 80% of the surgeons use the Rutledge measurements and method, 10% use the Carbajo antireflux method while 5% use the Tacchino 300-cm common limb.

If the weight loss is inadequate or excess during the process, the surgeon can modify the MGB by moving the anastomosis distally or proximally. Constructing a longer sleeve nearly to pylorus is the process that Bhanderi of India takes. Using robotics to perform the procedure is common for Prasad of India.

It is now common for the MGB to be performed post SG operation in order to regain weight. It is the consensus that the gastric pouch cannot be short for the MGB because it is opposite of the small proximal pouch of the RYGB. By creating a small or short gastric pouch in the MGB the old style Mason loop gastric bypass would be recreated and may cause bile reflux. The longer gastric pouch necessity was stated repeatedly by the presenters during the conference.

Survey Findings and Discussion

During the pre-conference a SurveyMonkey® questionnaire was handed out for answers and discussions. This largely academic surgical group carefully records data due to some early skepticism in its success. The results of the survey showed that 16,651 MGBs where performed by those that attended the conference. The average preoperative BMI showed to be 46.14.1 (SD) (range 38-62). The mean operating time showed to be 80.3 ±24.9 minutes (range 38-130). There was only 0.03% or 5 patients with leaks reported showing as less than the proximal leaks that follow SG operations. The average hospital stay for patients with the procedure showed to be 3.2 ±1.6 days (range 1.1-6.0).

The use of methylene blue or air test decreased with experience during surgery and the use of drain decreased as well as the experience grew. Most patients were mobile a few hours after the surgery.

At 1 year in 91.4 ±4.9% (range 82-96) diabetes had resolved. Peraglie reported that there was a resolution of co-morbidities and improvement in the quality of life as based on a personal experience with 1,400 MGBs, Cady with 2,500 MGBs Musella with 1,000 MGBs, Chevallier with 888 MGBs, Kular with 1,200 MGBs, W.J. Lee with >1,000 MGBs and Tacchino with 600 MGBs.

Bowel obstruction rarely occurred according to the survey with a 0.15 ±0.36% (range 0–1) none of which was a result of internal hernia. No intractable hypoglycemia has been reported.

In order to reduce the risk of marginal ulcer development it is important that the MGB is not performed on smokers, those that drink alcohol heavily or those that take salicylates. Patients in Kular, India appear to drink whiskey with no reported ill results, but the RYGB allows for more rapid absorption of alcohol.