# Duodenal Switch

> Citation bundle for Duodenal Switch on The Treatment Registry.
> URL: https://thetreatmentregistry.com/procedures/duodenal-switch
> Bundle URL: https://thetreatmentregistry.com/api/citations/procedures/duodenal-switch

- Category: weight-loss

## Description

The duodenal switch (DS) procedure, also known as a gastric reduction duodenal switch (GRDS), is a weight loss surgery procedure that is composed of a restrictive and a malabsorptive aspect.

## Overview

The duodenal switch (DS), also called gastric reduction duodenal switch (GRDS), is a weight-loss surgery that combines a restrictive and a malabsorptive component. In the restrictive part, roughly 70% of the stomach is removed along its greater curvature, together with most of the duodenum, leaving a smaller stomach. In the malabsorptive part, a long segment of the small intestine is rerouted into two separate pathways that meet at a shared common channel. The shorter digestive loop carries food from the stomach to the common channel, while the much longer biliopancreatic loop carries bile from the liver to the common channel. The common channel, usually about 75 to 150 centimetres long, is where the contents of the digestive path finally mix with bile before emptying into the large intestine. By shortening the length of intestine over which food and digestive juices mix, the procedure reduces the time available to capture calories and selectively limits the absorption of fat, so that after surgery patients absorb only about 20% of the fat they consume. A variation known as the loop duodenal switch bypasses a smaller portion of the small intestine than the traditional biliopancreatic diversion with duodenal switch (BPD-DS), which was associated with persistent malnutrition in some patients; the loop version is intended to reduce that risk, although long-term data on it remain limited. Because the procedure alters digestion so substantially, ongoing attention to nutrition is important, and malnutrition is regarded as an uncommon and preventable risk.

## Common risks

- Leak from perforation of the small bowel, duodenum or stomach
- Infection or abscess
- Deep vein thrombosis (blood clot)
- Pulmonary embolism (a clot travelling to the lungs)
- Vitamin and mineral deficiency
- Hernia and bowel obstruction
- Malnutrition, an uncommon and preventable longer-term risk

## FAQs

### How does the duodenal switch cause weight loss?

It combines a restrictive component, removing about 70% of the stomach, with a malabsorptive component that reroutes the small intestine. This reduces how much can be eaten and limits how much fat and how many calories the body absorbs.

### How much of the stomach is removed?

The restrictive part of the surgery removes approximately 70% of the stomach along its greater curvature, along with most of the duodenum, leaving a smaller stomach.

### What is the common channel?

The common channel is the length of small intestine, usually about 75 to 150 centimetres, where food from the digestive loop finally mixes with bile from the biliopancreatic loop before emptying into the large intestine. Its length influences how much fat is absorbed.

### How much fat is absorbed after the procedure?

The rerouting is designed to selectively limit fat absorption. As a result, following surgery patients absorb only approximately 20% of the fat they consume.

### What is the difference between the loop and traditional duodenal switch?

The traditional biliopancreatic diversion with duodenal switch led to persistent malnutrition in some patients. The loop duodenal switch bypasses a smaller portion of the small intestine to reduce that risk, though long-term data on the loop version are limited.

### What are the main risks?

Surgical risks include leaks from perforation, infection, abscess, blood clots and pulmonary emboli. Longer-term risks include vitamin and mineral deficiency, hernia and bowel obstruction; malnutrition is uncommon and preventable, which is why nutritional follow-up matters.