Mini Gastric Bypass

The mini gastric bypass procedure was first introduced in 1997 at University of North Carolina Hospital by trauma surgeon Dr. It was developed by Robert Rutledge as the first modification of the standard Billroth II procedure.

In 2018, IFSO declared that it considered mini gastric bypass among the main surgical techniques, but requested that the mini name not be used and instead only called Single Anastomotic Gastric Bypass.

Mini Gastric Bypass or Single Anastomosis Gastric Bypass?

Mini-Gastric Bypass, also known as single anastomosis gastric bypass, is a procedure that combines some of the features of sleeve gastrectomy surgery and a standard gastric bypass. A long stomach pouch is created. Afterwards, the created stomach pouch is combined with the small intestine piece.

Mini gastric bypass surgery is one of the most common bariatric surgeries. The main reason for this operation is the treatment of diseases such as diabetes, high cholesterol and high blood pressure due to excess weight. It can be applied to patients who have previously had gastric band or sleeve gastrectomy surgery but have failed to lose weight.

Eligibility criteria for mini gastric bypass surgery; Roux en y is the same as gastric bypass. Patients with metabolic syndrome and a BMI over 35 are suitable for mini gastric bypass surgery.

Number of Mini Gastric Bypass Applied in the World

The numbers of primary and revision mini gastric bypass are increasing compared to other methods. However, the rate of increase in the number of surgeries is not equal. While England, Israel, Egypt, Switzerland and Australia have adapted to the method much faster, there is still a prejudice against MGB in America.

Referring to the information in the IFSO Bariatric Surgery Database (2019), Prof. Dr. Almino Ramos points out that there is evidence showing that mini gastric bypass is superior to Roux-en-Y and sleeve gastrectomy surgery in weight loss in morbidly obese patients.

Mini gastric bypass, which is one of the mainstream bariatric surgery methods, is increasing not only in the number of cases, but also in terms of the number of studies and publications.

The key points in the technical details of the mini gastric bypass are as follows.

  • Although it does not change according to age or BMI, the diameter of the calibration tube should be between 34 and 40 mm.
  • The use of stapler line boosters is not standard.
  • Stomach-intestinal anastomosis should be 45 mm.
  • Division of the greater omentum is not routine, but should be done when necessary.
  • Measurement of total bowel length is not routine.
  • The minimum BMI range for non-obese diabetic patients is 25 – 30.
  • Roux-en-Y revision should be considered in severe reflux cases.
  • Routine postoperative use of gastric protector is 3 – 6 months.
  • Vitamins using for life; multivitamin, calcium, iron, vitamin D and a quarterly B12 injection.
  • Increasing the bypass distance is the most appropriate revision option for heavy weight regain.

The Greatest Advantages of Mini Gastric Bypass

The ideal bariatric surgery, performed with minimal risks and complications, is one of the methods that improves the quality of life by providing permanent weight loss. For this reason, mini gastric bypass really stands out as a method that is technically easy to implement. It is possible that it will be the most applied revision surgery in the coming years.

What are the Benefits of Mini Gastric Bypass?

After gastric bypass surgery, the patient loses approximately 10-15 kilos in the first month. The success rate of losing excess weight after surgery is higher than tube stomach. In both methods, food intake is limited. After the surgery, 75 percent of the excess weight is lost in the first year and 80-90 percent in the second year. With the loss of excess weight, a significant improvement is observed in diseases accompanying obesity.

Who is Suitable for Mini Gastric Bypass Surgery?

Mini gastric by-pass method is preferred in the treatment of insulin-dependent morbidly obese patients. It is more effective than tube stomach and classical gastric bypass surgery, especially in diabetic patients. Mini gastric bypass is generally the preferred method for morbidly obese patients who have had sleeve gastrectomy or gastric reduction surgery and regain weight after years. In these patients, the mini gastric bypass procedure is extremely easy and has few complications.

Mini gastric bypass; It is an operation that can take place between Roux – en – y with its absorption reduction effect and biliopancreatic diversion, which is a more complex surgery.

In patient selection for mini gastric bypass (MGB), the rules of other bariatric surgery methods are valid, and there are patient subgroups for which mini gastric bypass is particularly suitable.

  • Age and BMI: All patients who are eligible for bariatric surgery and who are in good health are candidates for MGB. However, in elderly patients, care should be taken about the absorption-reducing distance and should be kept a little shorter. Mini gastric bypass also has excellent results in super morbidly obese patients.
  • Metabolic diseases: Patients with extensive abdominal obesity or advanced metabolic syndrome are particularly suitable candidates for MGB due to its excellent effects. Its high metabolic efficiency makes mini gastric bypass an excellent option for patients with Type 2 diabetes, regardless of body mass index.
  • Reflux and Hiatal Hernia: Obese patients with reflux disease are also suitable candidates for mini gastric bypass due to its pressure-lowering effect.
  • Condition of the Small Intestine: Small intestines must be free in MGB surgery, as it contains small intestine anastomosis. In cases of frozen pelvis where the small intestine cannot be released, both mini gastric bypass and all mixed procedures involving the intestine are contraindicated.
  • Revision Surgery After Other Unsuccessful Surgery: It is stated that mini gastric bypass is an effective option in revision after failed restrictive surgeries such as gastric band and sleeve gastrectomy. Considering the popularity of sleeve gastrectomy today, it can be predicted that revision surgery from sleeve gastrectomy to mini gastric bypass will be the most common revision surgery in the coming years. Since mini gastric bypass is also an anti-reflux procedure, it is also a second option in cases of reflux after sleeve gastrectomy.
  • Special requirements: Morbidly obese patients should stop using alcohol and smoking at least 6 months before surgery. In case of any drug addiction, an eradication period of at least 3 years will be good. Since the risk of surgery is high in morbidly obese patients, mini gastric bypass is a very good option for these patients.

What Should Be Expected Weight Loss After Mini Gastric Bypass?

Compared to other bariatric surgeries, mini gastric bypass becomes one of the most powerful methods. The greatest weight loss after mini gastric bypass usually occurs in the first year. About 70 percent or more of the excess weight is lost during this time frame. Literature data show that weight loss continues to plateau in the second and third years, with a slowdown, and the rate of excess weight loss remains at the level of 75 percent in 8-10 years.

Many publications show the superiority of mini gastric bypass compared to sleeve gastrectomy. Mini gastric bypass is definitely more effective than Roux-en-Y gastric bypass and sleeve gastrectomy in terms of weight loss and improvement of chronic diseases. Because it is a more metabolic surgery, it is necessary to be careful against the higher risk of malnutrition.

Results Related to Age and Body Mass Index

Mini gastric bypass, which has become one of the most popular methods in bariatric surgery, accounts for approximately 46 percent of all bariatric surgeries. Mini gastric bypass is generally preferred to Roux-en-Y because it is an easier and more effective method. In addition, it is relatively easier to apply in super morbid obese patients, and its effectiveness is indisputably superior to both methods. In patients with a Body Mass Index (BMI) below 35, successful results are obtained similar to Roux-en-Y in terms of weight loss and resolution of metabolic complications.

In adolescents, mini gastric bypass provides effective weight loss and improvement in metabolic diseases. Gastric sleeve causes less medium and long-term complications compared to gastric band and RnY bypass.

What is the Recovery in Metabolic Diseases with Mini Gastric Bypass?

The success of mini gastric bypass, which is a valid bariatric surgery method today, on metabolic diseases has been proven.

When mini gastric bypass and sleeve gastrectomy surgery are compared, better results have been obtained with mini gastric bypass in both weight loss and diseases such as Type 2 diabetes, hypertension and sleep apnea.

Reflux and Stomach Hernia

There is a parallel relationship between obesity and reflux. Gastrointestinal junction in mini gastric bypass; food and gastric juices come into contact with a mixture of enzymes such as bile and pancreatic secretions.

In severe reflux cases, it may be appropriate to evaluate the adequacy of the lower esophageal sphincter with advanced tests such as pHmetry, impedance studies and manometry.

Mini Gastric Bypass and Quality of Life

Since quality of life includes physical, mental and social status, it is significantly lower in obese individuals. Quality of life is directly related to the amount of weight lost. Therefore, the improvement in mental status is multifaceted, from the reduction of depression symptoms to the increase of self-confidence.
Compared to other surgical methods, mini gastric bypass provides a simpler technique and a significant improvement in quality of life after a safe operation.

How is the Preparation for Mini Gastric Bypass Surgery?

As with other methods of obesity surgery, correct patient selection, preparation and education are very important in terms of achieving the best result. First of all, patients are evaluated comprehensively in terms of suitability for surgery.

Preoperative laboratory tests, including vitamin and mineral levels, must be performed. Before mini gastric bypass, patients should stop consuming alcohol and cigarettes at least 6 months before surgery.

The most important condition for achieving excellent results in the long term is patient education. Having detailed information about the surgery that the patients will undergo and being conscious of what they should do after the surgery directly increases the success rate.

Who Cannot Have Mini Gastric Bypass Surgery?

There are some contraindications that are valid for all bariatric surgeries. These details are;

  • Unacceptable risk of anesthesia,
  • Pregnancy,
  • Diagnosed cancer,
  • Active intra-abdominal infection,
  • Liver cirrhosis,
  • It is in the form of unstable psychopathological conditions and active drug addiction.

Some relative contraindications for bariatric surgery are as follows:

  • Inadequate treatment of the existing endocrine problem,
  • Smoking,
  • Low socio-economic status, anemia and nutritional deficiencies.

Mini gastric bypass is a very safe and effective procedure when done properly. However, standardization of the technique is imperative. If the technique is followed, the possible complications are almost non-existent.

How is Mini Gastric Bypass Surgery Performed?

With the laparoscopic method, mini gastric bypass surgery is performed through 4 holes of 0.5 cm and 1 cm opened on the abdominal wall. During this surgery, a small stomach pouch with a length of 15 cm and a width of 2 cm is created in the stomach with the help of staples, and this stomach pouch is connected between 180 – 200 cm of the small intestines. Thanks to this surgery, the stomach volume is reduced to 50 cc thanks to the mini pocket/pouch created from 1000 cc. Patients can feel full early even with 50 cc food intake. After mini gastric bypass surgery, diabetes can be eliminated by preventing and reducing the absorption of sugar and sugary foods taken orally from the intestine.

Comparison of Roux-en-Y Gastric Bypass and Mini Gastric Bypass

After the mini gastric bypass, sleeve gastrectomy and Roux-en-Y gastric bypass, it has become the most performed bariatric surgery in the world.

There are 3 randomized controlled trials in the literature comparing mini gastric bypass and Roux-en Y gastric bypass. In Lee’s study published in 2005, it was reported that mini gastric bypass caused fewer complications compared to 2-year follow-up results, there was no significant difference in weight loss in two years, and anemia was observed slightly more.
In the larger Ruiz – Tovar study published in 2019, it was stated that there was no significant difference in terms of surgery risks, but mini gastric bypass provided better weight loss and better control in diabetes, dyslipidemia and hypertension. The YOMEGA study of Robert et al., published in the same year, shows that the duration of mini gastric bypass surgery is shorter and the early complication rates are similar.

The current literature states that mini gastric bypass can be performed in a shorter time, has a higher effect on weight loss and metabolic comorbidities than Roux-en-Y gastric bypass, on the other hand, more nutritional complications and anemia may be encountered.

Surgical Solution of Mini Gastric Problems

The risk of encountering a long-term problem that needs to be corrected with surgery after mini gastric bypass is very low. In case of bleeding into the abdomen, classical surgical methods and diagnostic laparoscopy are the gold standard. Suture and omental flaps can be used in acute marginal ulcer bleeding. Similarly, gastric pos leaks and anastomotic leaks can be treated with sutures and omental flaps, unlike sleeve gastrectomy.

Leakage and Bleeding in Mini Gastric Bypass Surgery

As with all methods of bariatric surgery, acute postoperative bleeding is one of the most common postoperative complications. If the bleeding is not too severe, it can be managed conservatively with blood transfusion and follow-up. This situation can sometimes be resolved with endoscopic methods.

Gastric Ulcer

Gastric ulcer development in mini gastric bypass is not much different from RnY. Excessive acid production, alcohol, steroid and anticoagulant use and H. pylori infection can also lead to marginal ulcers.

Upper gastrointestinal endoscopy is the most important method for the diagnosis of gastroscopy. The presence of gastro-gastric fistula should be investigated in the endoscopy, and signs of erythema or perforation around the anastomosis should be evaluated.

Mini Gastric Bypass and Bile Reflux Discussion

The enterohepatic circulation of bile acids, their role in digestion and absorption, their metabolic effects and their close relationship with the microbiota are well known. Circulation of bile acids changes after gastric bypass types. A slight decrease in bile absorption in the biliopancreatic intestine is one of the most basic principles of mini gastric bypass surgery.

Bile is present at a lower rate in the common duct where the food enters, as bile acids are pre-absorbed. For this reason, these surgeries are known as bile-sparing surgery. One of the bad side effects of bile acid is diarrhea called cologenic diarrhea.

There is no clear data reporting a risk for cancer development after mini gastric bypass surgery.

Gastroesophageal Reflux Disease and Barrett's Esophagus

While the frequency of reflux is between 15 and 20 percent in the non-obese population, it is stated that this rate is between 50 and 100 percent in obese individuals. The esophageal mucosa transforms into a cylindrical epithelium that covers the stomach to protect itself. This condition is called intestinal metaplasia or Barrett’s Esophagus. Barrett’s Esophagus occurs in about 10 percent of severe reflux cases. Therefore, the presence of reflux disease or Barrett’s Esophagus should be evaluated with preoperative endoscopy. If there are no signs of esophagitis on endoscopy, impedance pH studies should be used to evaluate symptoms.

Biliopancreatic bowel length is the most important factor in malnutrition. As this distance gets shorter, the concentration of bile acids increases and the risk of biliary reflux develops in parallel.

Lifestyle changes and medication are the first steps to effectively treat Barrett’s esophagus and reflux disease. Weight loss with bariatric surgery is the main factor for improvement in reflux symptoms.

Decreased Absorption and Protein Calorie Malnutrition

As the missed bowel distance increases, the risk of malnutrition also increases. For this reason, these should be checked before the operation and the deficiencies should be completed. The most common missing values ​​are; B1, B6, B12, folate, iron, vitamin A, vitamin D, vitamin E, vitamin K, zinc and albumin. Macro and micro nutrients are absorbed from different parts of the digestive system. Therefore, various nutritional deficiencies can be seen after bariatric surgery.

Bile Tract Complications After Mini Gastric Bypass

Although stone formation in the gallbladder is quite common following bariatric surgery, the rate of symptomatic gallstones requiring gallbladder removal is 3.5 – 6.1 percent after sleeve gastrectomy surgery, and 6.1 – 10.6 percent after Roux-en-Y bypass. The rate of gallbladder surgery after mini gastric bypass was reported as 2%. Approximately 70 percent of patients with stones in the gallbladder do not show any symptoms. In symptomatic stones, bile surgery can be performed before bariatric surgery.

Weight Regain After Mini Gastric Bypass and Indications for Revisional Surgery

After Mini Gastric Bypass, reoperation may be required due to leakage, stenosis or ulcer perforations. Weight gain rate is low after mini gastric bypass. In this case, the method called Triple Attack can be used for revision. This approach includes reducing the gastric pouch, narrowing the anastomotic age and increasing the absorption-reducing intestinal distance.

Mini Gastric Bypass Revision Techniques

After mini gastric bypass surgery, revision surgeries may be required for various reasons such as bleeding, stenosis, perforation, excessive weight loss, unstoppable malnutrition, weight regain, insufficient weight loss or reflux.

Mini Gastric Bypass as Revision Surgery

An increasing number of revision surgery cases are occurring for inadequate weight loss or gain, especially after restrictive surgeries. Mini gastric bypass revision is one of the effective methods after gastric band and sleeve gastrectomy. Mini gastric bypass offers more successful weight loss than revisional Roux-en-Y.

Patient Follow-up After Mini Gastric Bypass

Since there may be vitamin and mineral deficiencies in obese patients before Mini Gastric Bypass, necessary examinations should be completed before the operation. Things to be completed and done before the operation;

  • Vitamins B1, B12, D
  • Calcium
  • Pylori eradication and endoscopy.

What to do after the surgery;

  • Full bio-chemistry examination in the 3rd, 6th, 9th and 12th months of the year.
  • Inspection every 6 months per year
  • Subsequent annual inspection
  • Vitamin B1, B12, D monitoring
  • Hb level, calcium, PTH monitoring and supplementation
  • Liver functional tests, monitoring of protein and albumin levels
  • Early ultrasound and endoscopy for cholecystitis at 6 and 9 months.

Use of Stomach Protector After Bypass Surgery

Marginal ulcer is a known complication in 1-16% of patients after gastric bypass surgeries. Most bariatric surgeons routinely use a stomach protector after surgery. The problem here is the intestinal mucosa, which is relatively vulnerable to acid attack. Factors causing ulcers;

  • Large stomach pouch
  • NSAID painkiller use
  • Cigarette consumption
  • Mucosal nutrition disorder
  • Gastrogastric fistula
  • Foreign body reaction and H.Pylori colonization.

Marginal ulcer formation can occur in the early or late stages. In early marginal ulcers, blood supply problems in the anastomosis may cause an increase in gastric acid in the late period. Although it has been thought that the use of gastroprotective after mini gastric bypass may reduce marginal ulceration, the duration of use is not clear.

Ideal Multidisciplinary Follow-up

An effective, high-quality and inclusive follow-up and care process is required after bariatric surgery. Multidisciplinary follow-up both increases success rates and improves quality of life.

The multidisciplinary team includes internists and endocrinologists specializing in obesity, anesthesiologists, nephrologists, hepatologists, respiratory diseases specialists, gynecologists, cardiologists, endoscopists, psychologists and nutritionists.

This team ensures that the patient is directed to bariatric surgery, weight loss is achieved and maintained, acute and chronic complications are recognized, and metabolic problems are corrected.