Duodenal Switch

The duodenal switch (also known as Bilio-Pancreatic Diversion with Duodenal Switch) procedure is a weight loss surgery that alters the gastrointestinal tract with two approaches: a restrictive aspect and a malabsorptive aspect.

The restrictive portion of the surgery reduces the stomach along the greater curvature so that the volume is approximately one third to one fifth of the original capacity. The malabsorptive portion of the surgery reroutes a lengthy portion of the small intestine, creating two separate pathways and one common pathway. The shorter of the two pathways, the digestive loop, takes food from the stomach to the large intestine. The much longer pathway, the bilio-pancreatic loop, carries bile from the liver to the common path. The common path is a stretch of small intestine, approximately 75-100 centimeters long, in which the contents of the digestive path mix with the bile from the bilio-pancreatic loop before emptying into the large intestine. The objective of this arrangement is to reduce the amount of time the body has to capture calories from food in the small intestine and to selectively limit the absorption of fat.

Advantages of the Duodenal Switch

The primary advantage of the duodenal switch surgery is that its combination of moderate intake restriction with substantial calorie malabsorption results in a very high percentage of excess weight loss for severely obese individuals, with a very low risk of significant weight regain.

Because the pyloric valve between the stomach and small intestine is preserved, people who have undergone the duodenal switch do not experience the dumping syndrome common with people who’ve undergone the Roux-en-Y gastric bypass surgery.

Those who undergo the duodenal switch often find that comorbidities such as (high blood pressure), diabetes mellitus type 2, and arthritis are significantly relieved in a short time after the surgery.

Some surgeons are so confident in the benefits of the duodenal switch that they will accept super-morbidly obese patients, who are often turned down for other weight loss surgeries.

Disadvantages of the Duodenal Switch

The malabsorptive element of the duodenal switch is so potent that those who undergo the procedure must take vitamin and mineral supplements above and beyond that of the normal population. Those that do not run the risk of deficiency diseases such as anemia and osteoporosis.

Because gallstones are a common complication rapid weight loss following any type of weight loss surgery, some surgeons may remove the gall bladder as a preventative measure during the duodenal switch. Others prefer to prescribe medication to reduce the risk of post-operative gallstones.

Far fewer surgeons perform the duodenal switch compared to other weight loss surgeries, in part because of the need for long-term nutritional follow-up and monitoring of duodenal switch patients.

Qualifications for the Duodenal Switch

The National Institutes of Health state that if you meet the following guidelines, weight loss surgery may be an appropriate measure for permanent weight loss

  • BMI of 40 or over
  • BMI of 35 or over with serious obesity-related illnesses such as:
    • Diabetes mellitus type 2
    • Coronary heart disease
    • Sleep apnea
  • An understanding of the operation and lifestyle changes necessary following the surgery.

Effectiveness of the Duodenal Switch

The following statistics are taken from Pacific Laparoscopy and Duodenal Switch Information Zone.

Weight loss

  • 3 months - 29 and 37%
  • 6 months - 51 and 55%
  • 24 months - 80 and 91%