The mini-gastric bypass, or single anastomosis gastric bypass, is an effective and well-established procedure which combines some of the properties of a gastric sleeve and a standard gastric bypass. The upper part of the stomach is divided into a tube, similar to the top three quarters of a sleeve, and then joined to a loop of intestine.The mini-gastric bypass can be used as a primary weight loss procedure. It can also be used in patients who have had previous gastric banding or sleeve surgery but have been unsuccessful with weight loss, or who have had band-related complications and have decided on revision surgery.
The mini-gastric bypass procedure is performed laparoscopically (keyhole surgery) under general anaesthesia. Five small incisions (between 5 and 12mm in length) are made for the insertion of the keyhole surgery instruments. Using these instruments, the top of the stomach is stapled to form a thin tube (30ml to 50ml in size). The thin tube becomes the new, smaller stomach and is completely separate to the rest of the stomach. This stomach is then sewn to a loop of the small intestine, bypassing the first part of the intestine called the duodenum and approximately 150–200cm of the bowel. The rest of the stomach and upper part of the small intestine remains in the body but is no longer used for food digestion.
Mini-gastric bypass is particularly effective for patients with a higher BMI as the procedure has more predictable and durable weight loss outcomes.Most patients have an almost immediate reduction in their need for diabetic medication and some are able to completely stop diabetic medication altogether. It is effective for those people who tend towards high sugar or high fat foods.