Bariatric Surgery (also known as obesity surgery or weight loss surgery) includes a variety of procedures performed on people suffering from obesity. It is done to help you lose excess weight and reduce your risk of potentially life-threatening weight-related health problems, including: type 2 diabetes, hypertension, infertility, sleep apnoea and others, that are documented to reduce life span of an obese patient by 7- 10 years.
Diet and Exercise should be the first choice of treatment for obese patients. Bariatric Surgery is typically done only if weight does not reduce or the lost weight quickly bounces back in spite of strict diet and exercise regimen.
Who is a Candidate for Bariatric Surgery?
In general, qualifications for bariatric surgery include:
- Body mass index (BMI) ≥ 37.5, or more than approx. 100 kilograms
- BMI ≥ 35 and at least one or more obesity-related co-morbidities, such as type 2 diabetes (T2DM), hypertension, sleep apnoea and other respiratory disorders, non-alcoholic fatty liver disease, osteoarthritis, lipid abnormalities, gastrointestinal disorders, or heart disease
- Inability to achieve a healthy weight loss sustained for a period of time with prior weight loss efforts
How Does Bariatric Surgery Work?
Bariatric surgery, such as gastric bypass and gastric sleeve work by changing the anatomy of your gastrointestinal tract (stomach and digestive system) or by causing different physiological changes in your body that change your energy balance and fat metabolism. Regardless of which bariatric surgery procedure you and your surgeon decide is best for you, it is important to remember that bariatric surgery is a “tool.” Weight loss success also depends on many other important factors, such as nutrition, exercise, behaviour modification, and more.
By changing your gastrointestinal anatomy, certain bariatric procedures affect the production of intestinal hormones in a way that reduces hunger and appetite and increases feelings of fullness (satiety). The end result is reduction in the desire to eat and in the frequency of eating.
How can Bariatric Surgery Help You?
When combined with a comprehensive treatment plan, bariatric surgery may often act as an effective tool to provide you with long term weight-loss and help you increase your quality of health. Bariatric surgery has been shown to help improve or resolve many obesity-related conditions, such as type 2 diabetes, high blood pressure, heart disease, and more. Frequently, individuals who improve their weight, find themselves taking less medications to treat their obesity-related conditions.
Types of Procedures
Bariatric surgical procedures cause weight loss by restricting the amount of food the stomach can hold, or causing malabsorption of nutrients, or by a combination of both gastric restriction and malabsorption. Most weight loss surgeries today are performed using minimally invasive techniques (laparoscopic surgery).
A. Roux-en-Y Gastric Bypass
The Roux-en-Y Gastric Bypass, often called gastric bypass, is considered the ‘gold standard’ of weight loss surgery.
There are two components to the procedure. First, a small stomach pouch is created by dividing the top of the stomach from the rest of the stomach. Next, the first portion of the small intestine is divided, and the bottom end of the divided small intestine is brought up and connected to the newly created small stomach pouch. The procedure is completed by connecting the top portion of the divided small intestine to the small intestine further down so that the stomach acids and digestive enzymes from the bypassed stomach and first portion of small intestine will eventually mix with the food.
The gastric bypass works by several mechanisms. First, similar to most bariatric procedures, the newly created stomach pouch is considerably smaller and facilitates significantly smaller meals, which translates into less calories consumed. Additionally, because there is less digestion of food by the smaller stomach pouch, and there is a segment of small intestine that would normally absorb calories as well as nutrients that no longer has food going through it, there is probably to some degree less absorption of calories and nutrients.
Most importantly, the rerouting of the food stream produces changes in gut hormones that promote satiety, suppress hunger, and reverse one of the primary mechanisms by which obesity induces type 2 diabetes.
- Produces significant long-term weight loss (60 to 80 percent excess weight loss)
- Restricts the amount of food that can be consumed
- May lead to conditions that increase energy expenditure
- Produces favourable changes in gut hormones that reduce appetite and enhance satiety
- Typical maintenance of > 50% excess weight loss
B. Mini Gastric Bypass
Mini-gastric bypass (MGB) is a promising bariatric procedure. It is a simpler procedure to perform compared to Roux-en-bypass. Mini gastric bypass has only one anastomosis between small pouch of stomach created just after oesophagus and second part of small intestine called jejunum compared to Roux-en-Y bypass that has two anastomoses.
- Completely reversible procedure
- Early sense of fullness and satisfaction
- Good for Indian patients
- Better weight loss than other bariatric procedures
C. Sleeve Gastrectomy
The Laparoscopic Sleeve Gastrectomy, often called the sleeve, is performed by removing approximately 80 percent of the stomach. The remaining stomach is a tubular pouch that resembles a banana.
This procedure works by several mechanisms. First, the new stomach pouch holds a considerably smaller volume than the normal stomach and helps to significantly reduce the amount of food (and thus calories) that can be consumed. The greater impact, however, seems to be the effect the surgery has on gut hormones that impact a number of factors including hunger, satiety, and blood sugar control.
Short term studies show that the sleeve is as effective as the Roux-en-Y gastric bypass in terms of weight loss and improvement or remission of diabetes. There is also evidence that suggest the sleeve, similar to the gastric bypass, is effective in improving type 2 diabetes independent of the weight loss. The complication rates of the sleeve fall between those of the adjustable gastric band and the Roux-en-Y gastric bypass.
- Restricts the amount of food the stomach can hold
- Induces rapid and significant weight loss that comparative studies find similar to that of the Roux-en-Y gastric bypass. Weight loss of > 50% for 3 - 5+ year data, and weight loss comparable to that of the bypass with maintenance of > 50%
- Requires no foreign objects (AGB), and no bypass or re-routing of the food stream (RYGB)
- Involves a relatively short hospital stay of approximately 2 days
- Causes favourable changes in gut hormones that suppress hunger, reduce appetite and improve satiety