Roux-en-Y gastric bypass (RGB): This operation is the most common gastric bypass surgery performed in the U.S.
First, a small stomach pouch is created by stapling part of the stomach together. This limits how much food you can eat. Next, a Y-shaped section of the small intestine is attached to the pouch to allow food to bypass the duodenum as well as the first portion of the jejunum. This causes reduced calorie and nutrient absorption. This procedure can now be done with a laparoscope (a thin telescope-like instrument for viewing inside the abdomen) in some people. This involves using small incisions and generally has a more rapid recovery time.
A gastric band device is introduced through tiny (1cm) incisions in the abdomen and is placed around the upper part of the stomach. The resulting pouch (or the "new stomach") dramatically reduces the functional capacity of the stomach. The band has a balloon from the inside that is adjustable and can reduce stoma size, thus prolonging the period of fullness.
The operation is performed under general anesthesia and can last between 30 minutes and 1 hour. The Band is fitted around the uppermost part of the stomach, forming a 15cc small pouch. It is designed so that it can be inflated or deflated at any time after the operation. This helps the patient continually lose weight until they reach their goals.
The vertical sleeve gastrectomy is a restrictive form of weight loss surgery in which approximately 85% of the stomach is removed leaving a cylindrical or sleeve shaped stomach with a capacity ranging from about 60 to 150 cc, depending upon the surgeon performing the procedure. Unlike many other forms of bariatric surgery, the outlet valve and the nerves to the stomach remain intact and, while the stomach is drastically reduced in size, its function is preserved. Again, unlike other forms of surgery such as the Roux en Y gastric bypass, the sleeve gastrectomy is not reversible.