Duodenal Switch Surgery Mexico / DS Surgery / Bariatric Procedure / Pioneer Dr. Gilberto Ungson

There are not many bariatric surgeons specialized in performing the duodenal Switch bariatric weight loss surgery. Duodenal Switch Surgery (DS) complexity is due to the important malabsorptive and metabolic aspects of the whole picture and is accomplished through the intestinal bypass effect that the process implies. As a consequence of the procedure, Duodenal Switch Surgery patients in Mexico eat in a relatively normal and free manner meanwhile their metabolism behaves pretty much to the one in a lean person.

Another Duodenal Switch (DS) aliases are:

  • Vertical Gastrectomy with Duodenal Switch
  • Biliopancreatic Diversion with Duodenal Switch (BPD-DS)
  • Gastric Reduction Duodenal Switch (GR-DS)

How does the Duodenal Switch work?

DS results in weight loss through any of these processes:

  • Limiting the amount of food intake by reducing the stomach’s size, cutting away its left side in an up-and-down motion, with the remaining pouch reduced into a long, slender tube
  • Rerouting the small intestine involves a metabolic effect happening after a modification in the intestinal hormones’ behavior limiting the amount of calories absorbed by the body.

These two parts of the Duodenal Switch (DS) are not reversible, and the patient’s stomach size ends up at 3 to 4 oz (90 to 1200cc) approximately in size, and we analyze these two parts in detail.


Duodenal Switch Surgery Mexico / DS Surgery / Bariatric Procedure/ Pioneer Dr. Gilberto Ungson

Restrictive aspect:

This part of the process is virtually considered a Vertical Sleeve Gastrectomy. Patients that have been through Duodenal Switch will experience food restriction rates that will change over time within a process called ‘pouch maturation’, reached about 9 to 12 months after DS surgery. At first stance, the patient’s stomach seems small, and it’s the starting point for weight loss. Then the stomach will stretch out gradually until reaching a food intake about half or two-thirds the amount of food they would eat before undergoing a Duodenal Switch procedure. And even though the stomach becomes of a smaller size after DS, none of it’s functions change.

These changes allow patients to enjoy different foods. Patients become able to follow their diet, knowing that quantities and digestion will become favorable for them by being capable of controlling their intake and limiting to the healthiest food available. One of the possible advantages for Ds patients -as opposed to those with a Gastric Bypass (RNY)- Duodenal Switch patients can eat dense protein(pork, steak, stew meat beef) with no problem at all, considering these as healthy protein sources. The anatomic configuration after DS provides patients of much healthier eating. Still, this freedom implies certain responsibility. While able to eat freely, DS patients must observe the healthiest way of eating possible their bodies allow. This is the restrictive part of a DS procedure.

Malabsorptive aspect:

Intestines are divided and rearranged so food is separated from digestive juices. The alimentary limb (the intestine portion carrying food) receives food from the stomach and is attached to the duodenum, and comprises less than half of the body’s intestinal tracts, consisting of the downstream of the intestine and the reaction to food it presents is rather different to the one by the upstream part of the intestine, the bypassed portion.

This bypassed portion carries digestive juices originated in the liver and pancreas and also consists of more than half of total intestinal length, joining the food limb towards the last 75 to 100 cm of intestine (known as common limb). This last portion is the only one capable of absorbing lipids, starches, fats and other complex carbohydrates. The size reduction of the intestine allows Duodenal Switch patients efficiently, since it is less than half of the intestine providing such function, so the excess starches and fats are excreted from the body in stoll.2 to 4 bowel movements a day are average for DS patients eating properly, while the ingestion of indigestible starches and lipids bring patients to experience a higher number of bowel movements per day.

Metabolic aspect:

Aside from the restrictive and malabsorptive nature of Duodenal Switch, there’s also a metabolic effect, whose improved mechanisms have a positive impact on weight loss. Apart from absorbing sugars and proteins from food intake, the alimentary limb of the intestines also secretes a hormone named enteroglucagon (also known as GLP-1) when undigested food is present. This secretion is enhanced after a Duodenal Switch procedure, since this part of the intestine is rearranged , thus causing an earlier pass of food through the alimentary limb. Also, the body normally secretes insulin as a response to carbohydrate consumption, but enteroglucagon is able to suppress this response so it reduces the total carbohydrate to be converted to and stored as fat.

Intestinal Limb Lengths and the Duodenal Switch Procedure

Understanding the Duodenal Switch offers a wide perspective of our knowledge regarding the length of the intestine to bypass (to keep destined to carry food) and how much should be allowed for food and digestive juices mixing.

The standard end length of the food limb for most bariatric weight loss surgeons is 150 cm, leaving the rest of the intestine for carrying digestive juices. The food and digestive juices mixture happens in the common limb, set at 100 cm. This is the most common configuration for Duodenal Switch, for a total of 250 cm in length.

But as we have mentioned earlier, not a single body is equal to another one, and every single patient should be approached as unique case, so custom intestinal lengths are set depending on the DS patient’s total small intestine length and/or other patient’s features, like any other surgical procedure, maximizing the benefit while reducing the risk is the primary goal traduces for Duodenal Switch into maximizing weight loss while minimizing malnutrition, and the intestine limb’s end lengths are set as to find a balance between both needs.


Advantages of a DS vs Gastric Bypass

  • Pylorus is preserved
  • Less possibility of Dumping
  • Ghrelin, hunger hormone is removed
  • More freedom of foods that can be eaten
  • Better weight loss results long term
  • Better Type 2 Diabetes remision