Duodenal Switch Surgery
According to the American Society for Bariatric Surgery and the National Institutes of Health, The Duodenal Switch (DS) is the most effective procedure for weight loss. The DS represents less than 2% of all weight loss procedures in the USA. This procedure is less commonly performed due to the higher resulting malabsorption and need for increased supplementation by the patients on a daily basis. In this malabsorptive procedure, stapling creates a larger sleeved stomach with approximately 60% of the lateral stomach permanently removed. The outlet from this newly formed sleeved stomach and duodenum is then separated. A long roux limb with a short (100-150cm) common channel is then created. The duodenum is then reconnected to the alimentary limb of the ileum. Food enters the stomach and then is diverted to this “roux” limb before coming into contact with digestive enzymes from the “BP” limb. The food and digestive enzymes are in contact for only a short common portion before entering the colon. This results in many of the ingested calories not being absorbed and they are subsequently disposed of by the colon. Because of the larger size of the stomach DS patients will not have the restriction that sleeve and gastric bypass patients experience. Due to the increased malabsorption these patients will need a substantially greater need for supplements on a daily basis to avoid malnutrition than other surgical patients. Undigested food (CHO, Proteins, and Fats) entering the colon may cause increased flatulence and loose bowels movements. This result to dietary intake makes learning new eating behaviors an important educational step in this process. Medications may also not be fully absorbed prior to entering the colon and might need more frequently dosing regiments to be as effective after this procedure. This procedure is only recommended for patients with BMI >50.
- Minimal restriction to meal portions
- Less Dumping syndrome due to pylorus preservation
- The average excess weight loss after the DS procedure is generally higher in a compliant patient than with any other procedure.
- 6 months after surgery, weight loss can average >80% of excess body weight.
- Less recidivism – Studies show that after 10 to 14 years, >60% of excess body weight loss has been maintained by most patients.
- A 2000 study of 500 patients showed that 96% of certain associated health conditions studied (back pain, sleep apnea, high blood pressure, diabetes and depression) were improved or resolved.
Risks and Considerations
- Because the duodenum is bypassed, poor absorption of iron and calcium can result in the lowering of total body iron and a predisposition to iron deficiency anemia.
- Bypassing the duodenum has caused metabolic bone disease in some patients, resulting in bone pain, loss of height, humped back and fractures of the ribs and hip bones. All of the deficiencies mentioned above, however, can be managed through proper diet and vitamin supplements.
- In some cases poor eating behavior (large portions of “greasy” food intake will result in foul smelling flatulence and numerous “urgent” loose stools.
- Considered by many patients to have a “high maintenance” supplemental need.
- Patients who lose too much weight may need revisional surgery to allow better absorption.