In Gastric Bypass surgery, a small pouch is created at the top of the stomach and permanently separated from the rest of the stomach. A segment of the small intestine is attached to the pouch, allowing food to bypass most of the stomach and the first part of the small intestine. The procedure is effective for weight loss because it reduces the amount of food that can be eaten at one time and because fewer calories are absorbed by the body.
Gastric bypass can be performed as open surgery or as a laparoscopic procedure. In the laparoscopic procedure, the surgeon operates through five or six small incisions in the abdomen. Using smaller incisions reduces the trauma, scarring and recovery time associated with traditional open gastric bypass surgery. Patients undergoing the laparoscopic gastric bypass generally spend less time in the hospital and resume normal activity quicker. However, not all patients are candidates for the laparoscopic technique, especially patients with an extremely high BMI or previous upper abdominal surgeries.
Gastric bypass surgery has been shown to be a durable and effective surgical option for weight loss. In the U.S., it is still the most common form of weight loss surgery. Most patients lose about half of their projected weight loss in the first six months, with weight loss peaking between 18 — 24 months.