Gastric bypass and banding are two types of bariatric surgery people can pursue if they are morbidly obese and want to lose weight. In gastric bypass, the structure of the stomach and digestive tract is permanently changed to shrink the stomach, radically reducing food intake. Gastric banding involves placing an inflatable band around the upper portion of the stomach to compress it, creating a small pocket for food. This procedure is reversible and carries fewer dangers than a gastric bypass.
Patients may be considered for bariatric surgeries like gastric bypass and banding if they have a body mass index (BMI) over 40, and need to lose at least 100 pounds (45 kilograms) to achieve a BMI in a more moderate range. Surgery can be highly effective for very heavy patients, but it carries serious risks patients should discuss with their surgeons. Patients may want to talk about both gastric bypass and banding to get information about the costs and benefits of each procedure.
Several different surgeries fall under the umbrella of “gastric bypass.” In all cases, the doctor separates the stomach into two pieces and reconnects the intestine. Surgeons commonly staple the stomach to separate it. This procedure is invasive and the patient can be at risk of complications like infection, rupture at the surgical site, or malnutrition associated with changes in how the digestive tract is laid out.
Gastric banding uses a flexible band with the possibility of adjusting the band over time as the patient loses weight and the stomach changes shape. In this procedure, the surgeon uses a band to create a pouch, leaving the pouch connected to the lower stomach. Food slowly works its way through the outlet between the two halves of the stomach, but the brain thinks the patient is full when the upper pouch is full, and will send a signal to stop eating. Gastric bands can fail or cause complications like leakage of stomach contents into the abdomen.
Both gastric bypass and banding require general anesthesia. It may be possible to perform the procedure with laparoscopic techniques. This will minimize scarring and shorten healing time. After gastric bypass and banding surgeries, patients go on a liquid diet to allow the stomach to adjust before switching to soft solids and eventually expanding the diet to firmer solids. Permanent dietary changes are necessary and weight loss programs are more successful if the patient also exercises after the surgery.