How is Gastric Bypass Performed?
Gastric bypass is a fairly complex procedure that typically takes between 1 to 4 hours. General anesthesia is required to perform the procedure. The surgeon will make a large incision along the abdomen if an open approach is used. However, if the gastric bypass is performed laparoscopically, several small incisions along the abdomen will be made.
As part of the procedure, the surgeon creates a small stomach pouch by dissecting the upper portion of the stomach using a stapling device. This small stomach pouch is usually approximately the size of a small egg. The small intestine is then cut into two portions. The lower portion of the intestine is then connected to the newly-created stomach pouch. The upper portion of the intestine called the duodenum is then reconnected to the rest of the intestine, resulting in a Y-type configuration.
The procedure induces weight loss in two different ways. It restricts the amount of food a person eats, because the feeling of “fullness” will occur much earlier than before. It also decreases the absorption of nutrients through the small bowel. Typically someone undergoing bariatric surgery will lose 50 to 80% of excess weight within 6 to 12 months.
In general, gastric bypass is not reversible, and it is a fairly complex surgery. It will, however, allow the largest amount of weight loss when compared to other weight loss procedures.