What is Gastric Bypass? All details!

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Candidates for wight loss surgery:     

Patients with body mass index between 35 kg/m2 and 40 kg/m2  plus a systemic disease like type 2 diabetes, hypertension or sleep apnea and the patients with body mass index of 40kg/m2 or more are considered as candidates for weight loss surgery. 

Weight loss surgery is accepted as the most effective treatment of obesity and obesity related diseases.

Obesity level is decided by calculating the Body Mass Index. If you divide your weight (kg) by the square of your height in meters, you will find your Body Mass Index.  

For example; 

In order to find the body mass index of an individual with 110 kg and 1.70 m, the calculation is 110 kg / 1.70m x1.70 m, that is:  110 / 2.89 m2 = 38 kg / m2. So the Body Mass Index is 38. 

From the point of view of obesity diagnosis, those with a Body Mass Index between 25-30 kg/m2 are Overweight, individuals with Body Mass Index between 30-35kg7m2 are at Stage 1 Obesity, 

those with a Body Mass Index between 35-40 are at Stage 2 Obesity, 

patients with a Body Mass Index of 40 and above are at Stage 3 Obesity or Morbidly Obesity level. 

Patients with a body mass index over 50 are diagnosed as a Super Morbidly Obesity Patients.   

In general, the patient group with a body mass index over 35 plus systemic diseases such as Sleep Apnea, Type 2 Diabetes, and Hypertension may consider obesity surgery  or so called weight loss surgery if they are unable to lose weight with diet and physical exercises.

Weight Loss Surgery types may be clasified mainly in two groups; restrictive and malabsorptive operations. 

1- Restrictive Weight Loss Procedures as an obesity treatment: These are the procedures like gastric sleeve surgery and gastric band operation. In the restrictive weight loss procedure the route of the food with in the digestive system is not diverted, thus there is no malabsorption. Only the diameter of the stomach is restricted that is why they are called restrictive weight loss procedures. In restrictive weight loss procedures there will be no nutrient malabsorption. The main weight loss effect of the restrictive procedures is the limitation in the calories consumed. Differently from gastric band procedure, gastric sleeve operation leads to a lowered appetite state due to the removal of the special part of the stomach called "FUNDUS" during the operation. Gastric sleeve suregry recentl is one of the most commonly perofrmed operation in the world. The numbers of gastric band operation is oppositely decreasing fastly due to high rate of early and late postoperative complications.    

2- Malabsorptive weight loss operations are called so because after the operation the route of the ingested nutrients will change in the digestive tract. In any malabsorptive operation there will be more or less nutrient and calorie malabsorption. Therefore life long witamin and some micro nutrients should be supplemented to he daily diet to avoid micro-nutrient deficiencies.  Malabsorptive weight loss operations are; Mini gastric bypass, Roux en-Y gastric bypass, SADI-S operation, Duodenal switch, Transit bipartition and Ileal interposition.

What is Gastric Bypass and what is its importance as a weight loss operation?

Gastric Bypass is one of the most commonly performed weight loss surgeries in the world. Previously gastric bypass was the most common type of weight loss surgery. The importance of gastric by pass is that it is not only a weight loss operation but also a metabolic surgery operation. With gastric bypass operation it is possible to obtain long term success in weight loss and weight preservation as well as a high success in treating type 2 diabetes and metabolic syndrome. Mainly there are 2 typoes of Gastric Bypass operations which are Roux-en-Y Gastric Bypass and Omega loop Bypass also known as Mini Gastric Bypass. There are slight differences between them still their effect mechanisms are same. Talking generally, Roux-en-Y type Gatsric Bypass is best for patients who suffer from gastro-esophageal reflux disease besides obesity and metabolic syndrome. Compared to Roux-en-y Gastric Bypass, it takes shorter time to perform Mini Gastric Bypass. Generally we have to say that since being a malabsorbtive surgery gastric-bypass is a bit more potent weight loss surgery compared to gastric sleeve. Especially in the special patient group called "Sweet eaters" gastric bypass is prominently more superior technic than gastric sleeve surgery. 

Generally Sleeve Gastrectomy (Gastric Sleeve) is more commonly performed surgery in all over the world. The reasons for that are gastric sleeve operation is a simplier and easier surgery.  It is performed in a shorter time period and there is no diverting in the digestive tract that is no malabsorption in gastric sleeve. Gastric Bypass surgery is preserved for patients with higher BMI, especially for super obese patients. If there are co-morbidities like Type 2 diabetes and metabolic syndrome gastric bypass surgery may be a better choice. And of course for those patients who have serious gastro-esophageal reflux disease and for those who are in the "Sweet eater" group gastric bypass would be the ideal surgery.

Another difference between gastric bypass and gastric sleeve occurs in the preoperative preparation period and in some decisions for some extra surgeries like cholecycstectomy together with gastric bypass surgery. Here the important point is that the patient has to know that after gastric bypass surgery, if any gall bladder stone develops, some complications of gall bladder stone disease may be challenging. For example the procedure called ERCP which is used to treat the gall bladder stones in the bile duct would be a great problem to perform because of the technical details of the bypass surgery. Therefore if there is a gall stone disease prior to the gastric bypass surgery gall bladder removal together with the gastric bypass surgery would be a logical option. And for those who do not have gall bladder stone at the time of the gastric bypass surgery, anti-gall bladder stone medications should be prescribed for at least 6 months after gastric bypass surgery. Please be aware that after any kind of weight loss surgery gall bladder stone formation risk increases seriously if anti gall bladder stone medications not prescribed.

Another important difference between gastric sleeve and gastric bypass surgeries is that the portion which is excluded from the stomach is removed out of the body in gastric sleeve, whereas the same portion of the stomach is left in the body in gastric bypass surgery. Therefore a very meticulous gastrocopic examination should be performed prior to the surgery, considering that the portion of the stomach left in the body would be like a closed box which can not be easily examined afterwards in gastric bypass technic.

After gastric sleeve (sleeve gastrectomy) operation multivitamin supplementation is advised generally for a year, however due to malabsorptive properties, after gastric bypass surgery multivitamin supplementation should becontinue dlife long and close vitamin status follow up is mandatory after gastric bypass.

Omega loop type (Mini Gastric Bypass) takes arounds 100-120 minutes to perform, the approximate time duration for Roux-en-Y type gastric bypass is around 150-180 minutes