The duodenal switch is a weight loss operation that has been done for over 20 years but has increased in frequency significantly in the last several years. It has the greatest weight loss potential of all the operations available. It works by creating a sleeve gastrectomy for restriction and hunger control. Then, after the sleeve, the intestines are rerouted similar to a gastric bypass. The principle measured length with a duodenal switch is the common channel. This is the distance from where bile and food meet to the end of the intestines and determines the amount of malabsorption.
This common channel distance is an important number and has changed significantly over time. Originally this number was 50-100 cm and while it provided excellent weight loss, it left patients with nutritional deficiencies and diarrhea. We currently do a common channel length of 300 cm for most procedures. Deviations from this number are dependent on the patient’s needs and this appears to be the sweet spot where weight loss is still excellent with fewer downsides. Vitamin supplementation is important and patients may have some increase in the number of bowel movements.
Surgery takes about an hour and a half and patients have a similar recovery to the other procedures. The dietary progression is the same. Food enters the sleeve and is held there with the pylorus just like a sleeve. Because of this the dumping syndrome does not occur unlike the gastric bypass.
The ideal patient for a duodenal switch is a patient who has more weight to lose. We know that patients will lose more weight than the other surgical options. Particularly patients with a BMI over 50 will have better and more sustained weight loss than with other procedures. Additional benefits are a lower incidence of ulcers than a gastric bypass operation. This is particularly helpful for patients that need to take NSAIDs such as aspirin, ibuprofen etc.
Patients can expect to lose 80-90% of excess weight in the first year after a duodenal switch operation.*
*Results will vary between patients