What Is The Gastric Bypass Surgery?

Gastric bypass is one of the most common types of bariatric surgery combining restrictive and malabsorptive procedures.

Technically, during this procedure a small pouch is created to shrink the stomach and a certain segment of the small intestine is brought up and connected to this small pouch. Unlike sleeve gastrectomy, the remnant of the stomach is not removed.

However food does not enter into the remnant section of the stomach while the gastric juice and enzymes are still produced in this section to contribute to the digestion and absorption of the food. In this way, patients who have undergone the gastric bypass procedure lose weight as they eat less and the calorie intake is limited as a result of the smaller size of the stomach while the absorption of high-calorie nutrients is also reduced as a result of direct connection between the remaining pouch and the small intestine. Therefore this procedure can help losing weight by two different mechanisms.

Gastric bypass procedures performed by laparoscopy are not associated with deep skin incisions and associated pain. The procedure is performed under general anesthesia and on the average, it lasts for one hour.


Gastric bypass is a perfect mean to achieve long-term weight control by reducing the appetite and allowing small portions of food. Most of patients successfully lose weight and maintain their excess weight loss in long term.

Weight loss provides permanent resolution of obesity-associated co-morbidities, notably diabetes mellitus type 2. The rates of postoperative patient satisfaction are high in terms of psychological and physical effects.


As with any surgical procedure, there are potential risks and complications associated with the gastric bypass procedure. These risks and complications are rare and all measures are taken to prevent them from occurring.

The most known complications include anastomotic leakage, bleeding and embolism. These complications are more likely to occur during the first 15 days after surgery.

Please contact your doctor immediately after becoming aware of the first signs of such complications as early detection may decrease treatment duration and may have a positive impact on treatment outcomes.

Staple line leakages are the most serious complications of this procedure. Signs and symptoms of a leakage include elevated body temperature, severe abdominal pain, a high pulse rate, chills and fatigue.

A timely and successful intervention of your doctor is the key to the treatment of a potential leakage. The detection and treatment of a leakage is quite easy for an experienced bariatric surgeon. However, such complications will prolong the healing process.
Another risk is the risk for embolism. Any surgical procedure is associated with a risk for embolism; however, this risk for embolism is higher in bariatric surgery procedures in association with excess weight.

An injectable blood thinner is started on the day of surgery and patients wear compression stockings (stockings for varicose veins) to reduce the risk for embolism. Patients have to wear compression stockings and receive blood thinner injections at home for an additional 10 days after their discharge from the hospital.

Bleeding is the most common complication of the procedure. Drain monitoring facilitates the observation of a potential bleeding. The signs and symptoms of bleeding include fatigue, dizziness and low blood pressure. The treatment of bleeding consists of blood transfusions according to the amount of the bleeding and this complication can be easily overcome.

In addition to these complications, vitamin and mineral deficiencies may occur as a result of inadequate nutrition and absorption. Patients should undergo blood test regularly after the surgery to check if such deficiencies occur and should receive medications and supplements prescribed by their doctor.

Rapid gastric emptying, also called ‘Dumping Syndrome’ may occur as a result of very rapid passage of food, particularly sugar into the small intestines.

Symptoms of dumping syndrome appear 10 to 30 minutes after the food intake and include abdominal pain, cramps, and diarrhea. Dumping Syndrome may be avoided by eating smaller meals and limiting high-sugar food.


Following a gastric bypass procedure, patients undergo a leak test on the postoperative Day 2 and a 15-day liquid diet is started. The liquid diet period is followed by a pureed food diet and solid food is added after then. Periods of Diet will be explained carefully to you by your dietician.

The role of dieticians is of paramount importance for every patient during the postoperative period. Dietary compliance of the patient is the most important factor to prevent complications from occurring.

Patients should gain the habit of eating slowly with small bites and chewing very well. Another rule of nutrition is making the distinction between the solid food and liquid food.

The interval between food and liquids should be at least 30 minutes. In this way nutritional deficiencies and gastric enlargement may be prevented from occurring.

It is important to comply with fiber- rich meal plans with a balanced ratio of carbohydrates to protein and fat. The meal plan should contain about 60 to 80 g of protein a day to ensure wound healing and to avoid nutritional deficiencies. The sources to supply the required amount of protein may vary according to the tolerance of each individual patient.

As the tolerance increases in time, the consumption of protein-rich food increases. Furthermore mineral deficiencies including iron, calcium deficiencies which may result in iron deficiency anemia or osteoporosis as well as Vitamin B12 deficiency are common following this procedure.

In addition to a nutritious diet, B complex vitamins and multivitamin supplements may be needed. Patient have to break their old eating habits such as frequent high-sugar and high calorie meals and get new healthy eating habits to avoid symptoms such as cramps or diarrhea associated with dumping syndrome as well to avoid from regaining lost weight.

consultation form