Bariatric Surgery

Sometimes obesity cannot be treated by diet and exercise alone. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) says gastrointestinal surgery or bariatric surgery can be the best option for people who are severely obese and cannot lose weight by traditional means or who suffer from serious obesity-related health problems. By severely obese, NIDDK means having a body mass index of over 40, or being at least 80-100 pounds overweight. (Read about "Body Mass Index" "Obesity")

NIDDK says you may be a candidate for surgery if you have:

• a body mass index (BMI) of 40 or more - about 100 pounds overweight for men and 80 pounds for women
• a BMI between 35 and 39.9 and a serious obesity-related health problem such as type 2 diabetes, heart disease, or severe sleep apnea (when breathing stops for short periods during sleep) (Read about "Diabetes" "Coronary Heart Disease" "Sleep")
• an understanding of the operation and the lifestyle changes you will need to make.

Surgery basically works by reducing the amount of food absorbed during the digestive process. (Read about "Digestive System") Normally, digestion starts as we chew and swallow our food, and the food moves down the esophagus to the stomach. The stomach can hold about 3 pints of food at one time. When the stomach contents move to the duodenum, the first segment of the small intestine, digestion speeds up. Most of the iron and calcium (Read about "Vitamins & Minerals" "Calcium") in the foods we eat is absorbed in the duodenum. The jejunum and ileum, the remaining two segments of the nearly 20 feet of small intestine, complete the absorption of almost all calories and nutrients. The food particles that cannot be digested in the small intestine are stored in the large intestine until eliminated. Bariatric surgery alters this process.

NIDDK says there are four types of operations that are commonly used in the United States. They are:

• Adjustable Gastric Band - AGB works primarily by decreasing food intake. Food intake is limited by placing a small bracelet-like band around the top of the stomach to produce a small pouch. This pouch limits the amount of food that can be eaten at one time, making you feel full faster. The narrowed opening between the pouch and the rest of the stomach controls how fast food passes to the lower part of the stomach. The size of this opening can be adjusted after the procedure without additional surgery, in order to meet the needs of the patient.
• Roux-en-Y Gastric Bypass - RYGB works by restricting food intake and by decreasing the absorption of food. Food intake is limited by a small pouch that is similar in size to the adjustable gastric band. In addition, absorption of food in the digestive tract is reduced by excluding most of the stomach, duodenum, and upper intestine from contact with food by routing food directly from the pouch into the small intestine.

• Biliopancreatic Diversion With a Duodenal Switch - BPD-DS, usually referred to as a "duodenal switch," is a complex bariatric operation that principally includes:

  • removing a large portion of the stomach to promote smaller meal sizes
  • re-routing of food away from much of the small intestine to partially prevent absorption of food
  • re-routing of bile and other digestive juices which impair digestion

  In removing a large portion of the stomach, a more tubular "gastric sleeve" (also known as a vertical sleeve gastrectomy, or VSG) is created. The smaller stomach sleeve remains connected to a very short segment of the duodenum, which is then directly connected to a lower part of the small intestine. This operation leaves a small portion of the duodenum available for food and the absorption of some vitamins and minerals. However, food that is eaten by the patient bypasses the majority of the duodenum. The distance between the stomach and colon is made much shorter after this operation, thus promoting malabsorption. BPD-DS produces significant weight loss. However, there is greater risk of long-term complications because of decreased absorption of food, vitamins, and minerals. (Read about "Vitamins & Minerals")

• Gastric Sleeve / Vertical Sleeve Gastrectomy - VSG historically had been performed as the first stage of another bariatric procedure. However, some patients who undergo a VSG can actually lose significant weight with VSG alone and avoid a second procedure. A VSG operation restricts food intake by removing a significant portion of the stomach and does not lead to decreased absorption of food. The procedure may also decrease production of a hormone called ghrelin. A decreased amount of ghrelin may reduce hunger more than other purely restrictive operations, such as gastric band.

Each has its own benefits and risks. You need to have a frank discussion with your doctor to select the option that is best for you. Be sure to discuss the operation's benefits and risks along with many other factors, including BMI, eating behaviors, obesity-related health conditions, and previous operations.

Surgery to produce weight loss is a serious undertaking. Side effects can include nausea, dehydration and constipation. (Read about "Dehydration" "Constipation") Rapid gastric emptying or dumping syndrome is also common, especially if you do not follow your doctor's diet directions. (Read about "Rapid Gastric Emptying") Anyone thinking about surgery should understand what the operation involves. Patients and physicians should carefully consider the benefits and risks. In some procedures, minimally invasive robotic-assisted surgery is an option. (Read about "Robotic Surgery") It's also important to note that success is possible only with maximum cooperation and commitment to behavioral change and lifelong medical follow-up. (Read about "Learn About Your Procedure")