Disease overview
Obesity is a chronic condition in which there is an excessive accumulation of fat in the body. Obesity is defined as a Body Mass Index (BMI) of 30 to 34.9 and extreme obesity is a BMI of 40 or more. When a person’s BMI is 50 or higher, it is referred to as super obesity. Obesity is a global problem affecting people of almost all age groups and is associated with a greatly increased risk of chronic diseases.

Indications
Gastric bypass surgery may be recommended when diet, exercise or medications have not helped in reducing your weight. It is indicated for people with a BMI of 40 or more, and also in those whose BMI is 35 to 39 that are suffering from obesity associated health conditions such as:

Type 2 diabetes
Heart disease
High blood pressure
High cholesterol
Sleep apnoea
Non-alcoholic fatty liver disease
Cancer

Surgery:
Gastric bypass surgery is performed under general anaesthesia. Your surgeon makes several small incisions on your abdomen. A laparoscope, a thin instrument with a light and camera on the end, is inserted through one of the incisions, allowing your surgeon to clearly view the internal organs on a monitor. Small surgical instruments are inserted through the other incisions to perform the surgery.

The first step is to reduce the size of the stomach so that it holds less food. The upper portion of the stomach near the oesophagus is converted into a pouch by stapling.

The second step of the surgery involves the creation of a bypass for food to flow from the new stomach pouch. The small intestine is divided into upper and lower segments.

The lower section of intestine is attached to the opening in the stomach pouch creating what is referred to as the “roux limb”. The upper section of the small intestine which carries digestive juices from the remaining portion of the stomach is attached at the distal end of the roux limb. The roux limb enables food to bypass the lower stomach, duodenum, and a portion of the small intestine. At the end of the procedure, the incisions are closed with sutures

Post-operative care:
After gastric bypass surgery, you will have to stay in the hospital for about 2 to 5 days. Your doctor will prescribe pain relieving medications to keep you comfortable. You will be given instructions to follow regarding wound care, diet and activity such as:

Keep the incision area clean and dry.
Avoid strenuous exercises and lifting heavy weights
You will be put on a liquid diet followed by pureed or soft foods.
Sip water throughout the day to prevent dehydration.
Follow the diet regimen given to you by the dietician.
Follow an exercise program per your surgeon’s instructions to maintain the weight loss.

Advantages and disadvantages

Gastric bypass surgery can help you lose about 10 to 20 pounds a month in the first year following surgery. You will gradually lose more weight by eating a healthy diet and participating in regular exercise. The surgery also helps you manage obesity-related health conditions.

Disadvantages:
Lifelong follow up with a physician is required for blood tests to ensure proper health and nutrition.
Risks and complications:
As with any surgery there are potential risks and complications involved. Complications associated with gastric bypass include:

Problems associated with anaesthesia
Bleeding
Infection
Bowel obstruction
Leaks in your gastrointestinal tract
Deep vein thrombosis (blood clot in the leg)
Dumping syndrome leading to diarrhoea and nausea
Hernia
Gallstones
Malnutrition
Ulcers

Mini gastric bypass
Gastric bypass is a surgical procedure to treat obesity that involves reducing the size of your stomach to facilitate early satiety, and bypassing a section of your intestine to limit food absorption. A gastric bypass procedure is usually carried out by a Roux-En-Y procedure where your stomach and intestine are reconnected (anastomosed) in two places. A single anastomosis gastric bypass or mini gastric bypass is a modification that simplifies this procedure, reducing operating time and complications.

Like any bariatric surgery, mini gastric bypass is indicated when obesity endangers your health, eating habits are difficult to control and significant weight loss is not achieved through diet and exercise.

Mini gastric bypass operation is performed under general anaesthesia. The procedure may be performed by open surgery (making a large incision) or a laparoscopic method, which involves making 3 to 4 small incisions through which a camera and small instruments are introduced. Your stomach is first stapled so that a pouch is created separate from the rest of your stomach. In the Roux-En-Y procedure, the intestine is then divided and one end connected to the stomach pouch while the other end is reconnected back to the intestine. With mini gastric bypass, the pouch is connected (anastomosed) after the duodenum without making a division in the intestine. Following the procedure, your incisions are closed.

As with any surgical procedure, a mini gastric bypass may be associated with risks such as infection, bile reflux and nutritional deficiency.

Frequently Asked Patient Questions
What is gastric bypass surgery?
Gastric bypass surgery is a restrictive/malabsorptive surgical procedure. It is restrictive in the sense that it “restricts” how much food the stomach can hold and is “malabsorptive” in that it affects how food and calories are absorbed into the bloodstream. This combination surgery has the highest success rate for amount of weight lost.

How is the surgery performed?
The surgeon makes the stomach smaller by creating a small stomach pouch by stapling along the upper part of the stomach. A new opening from this pouch is created as well. The small intestine is then cut into two sections. The lower section of intestine is attached to the opening in the stomach pouch creating what is referred to as the “roux limb”. The upper section of the small intestine which carries digestive juices from the remaining portion of the stomach is attached at the distal end of the roux limb. The roux limb enables food to bypass the lower stomach, duodenum, and a portion of the small intestine.

How much weight will I lose?
Studies have shown that gastric bypass patients can lose up to 90 percent of their excess body weight. 75% of patients will lose 75-80% of their excess body weight after surgery.

What can I expect after the surgery when I eat?
You will only be able to eat a few ounces of food at a time. You will not be able to drink and eat at the same time as your new stomach will not be able to hold both. You will also have to concentrate on eating slower and chewing your food thoroughly. You will also have to avoid certain sugary foods as these can lead to “dumping syndrome”.

What is dumping syndrome?
Dumping syndrome happens when the food you eat passes too quickly through your new GI tract causing diarrhoea, shakes, sweats, and other unpleasant symptoms. Dumping syndrome can be avoided by not eating sugary foods such as candy, juices, sodas, and other foods high in simple sugars.

What are the advantages of gastric bypass surgery?
Advantages of gastric bypass surgery includes:

Quick and dramatic weight loss
Continued weight loss for 18-24 months’ post-surgery
Many patients maintain a weight loss of 60-70% of excess weight 10 years’ post-op
Improved health problems associated with severe obesity such as diabetes, high blood pressure, arthritis, asthma and sleep apnoea.
Many patients are able to stop taking medications for diabetes and hypertension as a result of the weight loss.
Improved mobility and quality of life and self-esteem.
What are the disadvantages of gastric bypass surgery?
Disadvantages of gastric bypass surgery include:

Malnourishment and anaemia may occur requiring lifelong vitamin and mineral supplementation.
Requires permanent lifelong changes to patient’s diet and lifestyle
Increased risk of gallstones due to rapid weight loss
Dumping syndrome: nausea, reflux, diarrhoea can occur after ingesting high sugar foods