The biliopancreatic diversion with duodenal switch (BPD/DS) is a bariatric surgery performed to reduce weight in people with morbid obesity (class 3 obesity) or those with class 1 or 2 obesity having any of the health complications associated with obesity, 

Usually referred to as the duodenal switch, BPD/DS surgery for weight loss combines the restrictive as well as the malabsorptive approach to reduce weight in obesity. Primarily though, the malabsorptive approach is important here to aid in weight loss. It is also known as the gastric reduction duodenal switch.

This surgery is a combination of gastrectomy (removal of part of your stomach) and an intestinal bypass, which makes the path of your food through your intestines shorter.

Besides restricting the amount of food your stomach can hold, it also limits the nutrition your small intestine can absorb from your food.

In general, interest in the duodenal switch is gathering momentum judging from the fact that about 20,000 duodenal switch surgeries are performed in the U.S. annually.

BPD/DS surgery procedure

The surgery is done using a laparoscope which involves inserting instruments through multiple small incisions in your abdomen or through a large open incision in the abdomen. It is performed in two steps: the restrictive approach and the malabsorptive approach. Each part of the surgery usually takes a few hours.

  • The restrictive approach involves removing about 70% to 85% of the stomach and forming the remaining portion into a narrow sleeve. The resection of the stomach is on a vertical plane so that the greater curvature of the stomach is left out of the path of food. The stomach capacity is reduced to about 6 ounces only. Your surgeon leaves the pyloric valve intact, along with a limited portion of the small intestine (duodenum) that normally connects to the stomach.
  • The malabsorptive approach involves creating two channels of the small intestine. One pathway carries food from the stomach to the distal end of the small intestines and the other pathway carries the bile from the liver to that part of the small intestine where the first pathway meets it. The common channel into which both these pathways empty is about 75 to 150 cm long where the bile mixes with the food before entering the large intestine. Due to this quick passage of food into the distal part of the small intestine, the time and area for absorption of food are much reduced leading to the absorption of only 20% of the fats or calories in the food. This is done to bypass a large segment of the small intestine.


Your healthcare provider may advise bariatric surgery if you are morbidly obese and have failed to reduce your weight with weight loss dietary restrictions and regular physical exercise.

He may even recommend this surgery if you are just obese and have health complications of obesity.

Therefore, the indications boil down to the following two conditions:

  • An obese person with a BMI of 40 or more
  • Any obese person with a BMI more than 35 and associated with any of the obesity risks like diabetes, high blood pressure, sleep apnea, etc.

Although it has a higher rate of complications, for people who are severely obese and with more severe health conditions, the benefits outweigh the risks.

How much weight can you lose with a duodenal switch?

The duodenal switch produces the most intense weight loss results of all bariatric procedures. It produces dramatic improvement in obesity complications such as metabolic syndromes and their accompanying comorbidities such as type 2 diabetes.

The duodenal switch helps you lose about 80% of your excess weight over a two-year period. This loss of weight is more than the average weight loss from bariatric surgery, which reduces about 50% to 60%.

It also helps you maintain this weight loss over a longer period. Studies show an average continuous weight loss of 70% of excess weight over ten years.

Advantages of duodenal switch surgery

  • Duodenal switch surgery has a 90% success rate for weight loss – that’s more than with other bariatric surgeries.
  • It also helps you get rid of obesity comorbidities. As much as 90% of people with Type 2 diabetes are able to discontinue their medications after this surgery.
  • This weight loss surgery combines a moderate amount of restrictive approach and a substantial amount of malabsorptive approach. As a result, weight loss success is high with a very low weight regain rate.
  • Obese people who have had other obesity complications show a marked improvement in their diabetes, high blood pressure, cholesterol levels, and sleep apnea.
  • No dumping syndrome or marginal ulcers are seen in DS surgery unlike with other bariatric surgeries because the pyloric valve is preserved.
  • Post-operative tolerance of diet is better.
  • Malabsorptive changes can be reversed if necessary because no part of the intestine is removed.
  • When other surgeries fail to produce enough weight loss, some people are advised to undergo revision surgery with a duodenal switch.

Disadvantages of duodenal switch

  • The restrictive part of the surgery cannot be reversed.
  • Nutritional supplements are necessary post-operatively and periodic tests to test for nutritional adequacies become necessary.
  • Due to the risk of gallstones post-operatively, gall bladder removal is advised as is the case with other bariatric surgeries.
  • Higher occurrence of diarrhea and flatulence
  • Insurance companies still have to bring duodenal switch surgery under their gambit. They still consider this surgery in an experimental stage.

Complications and risks

  • Perforation of the stomach or small intestine leads to leakage of the contents from within to outside the gastrointestinal tract.
  • Infection can lead to an abscess.
  • Deep vein thrombosis can lead to a pulmonary embolus.
  • Bowel obstruction can occur due to adhesions.
  • Internal hernia can develop in the long term.

Cost of surgery

The cost of this surgery in the United States is about $20,000  which covers

  • hospital charges,
  • Surgeon fees,
  • Anesthesia,
  • Pathology charges,
  • Radiology charges
  • This figure does not cover the duodenal switch post-operative costs of cosmetic surgery or behavior modification therapy.

After surgery

You will need to follow up with your health provider more closely for a year or two. He will look for signs of any post-operative complications and test you for any nutritional deficiency. Vitamin and mineral supplements will your friends throughout life to prevent malnutrition.

You will need to follow dietary restrictions. Immediately after the DS procedure, you may have liquids only and no solid food as your stomach and intestines begin to heal.

Your special diet plan that changes will gradually change from liquids to pureed foods. Later, you can eat soft foods when your body is able to tolerate them.

Your dietary restrictions will continue in regard to how much and what you can eat and drink.