Previously known as Mini-Gastric Bypass or MGB, this operation is relatively new and old. It is considered new from the bariatric standpoint, since it does resemble the Roux En-Y Gastric Bypass (LRYGB), but differs in these aspects:
- Size of the gastric pouch (the new stomach used for food) is much longer (18-20 cm as opposed to 4-5 cm).
- The length of the bowel bypassed is usually 2 meters (longer than the standard proximal bypass, but it is being reduced nowadays due to reports of malnutrition to 1.5 meters)
- Only one connection (anastomosis) is made: between the bowel and the gastric pouch. No anastomosis between the small bowel is made as in the LRYGB.
We offer this procedure selectively for patients who do not have heartburn or reflux, older age, and higher weight . The unique risks of this procedure are:
- Bile reflux: As bile passes through the stomach pouch, and can reflux back into the esophagus less often. However, bile reflux gastritis still occurs in about 10% of cases while esophagitis in up to 4%, severe enough to require a revision to be converted to LRYGB.
- Acid reflux: The pouch is big enough to produce acid, with a higher potential for acid reflux. This is why, newer international guidelines recommend patients who undergo the OAGB, have annual upper endoscopy to check for bile reflux gastritis or esophagitis. If present and is significant, and medical treatment is not successful in it control, patients will need revision to LRYGB.
- It also carries the risk of malabsorption, protein-calorie malnutrition, and especially iron deficiency causing anemia with vitamin D deficiency.
- Higher risk or marginal ulcers due to smoking or the use of non-steroidal anti-inflammatory drugs (NSAIDs).
The Advantages of this procedure may be:
- Potential less dumping symptoms experienced by patients and less hyperinsular state as suggested by some studies. It is almost similar to LRYGB in its Diabetes resolution, leak rates and the rest of the complications.
- Potentially superior to LRYGB in maintaining the long term weight loss at 80% of the excess weight.
Some surgeons would like to advertise this procedure as a safer procedure to LRYGB. In our experience, it is as safe short-term, but long-term carry the risk of bile reflux is not yet known to judge. Vitamin & iron requirements are more in comparison to LRYGB as well. This is why we offer it selectively to patients with body mass index (BMI) > 45 Kg/m2, without reflux disease and a normal endoscopy. Our surgeons led international studies that were published to help surgeons understand the nature of OAGB as a procedure with its potential complications.