Mini-Gastric Bypass Surgery


Mini Gastric Bypass Surgery

The One Anastomosis Gastric Bypass (OAGB), also known as “mini-gastric bypass” was first reported in 2001. The OAGB is a minimally invasive procedure performed with laparoscopic technique.

During a OAGB procedure, the surgeon first reduces the size of the “working” stomach by separating a tube-like pouch of stomach from the rest of the stomach. This tubular gastric pouch is then connected (anastomosed) to the intestine, bypassing up to 200cm of the upper part of the intestine.

This technique differs from the traditional Roux-en-Y Bypass (RYGB) which requires two connections (anastomoses).

A OAGB typically results in 30% to 40 % body weight loss from baseline (60-80% excess weight loss). The most rapid weight loss occurs in the first 6 months after surgery and then continues at a slower pace for up to another 18 months.This weight loss is achieved through both restriction (the new gastric pouch can hold only a small quantity of food) and malabsorption. Bypassing a sizable segment of the intestine, the remaining intestine is not long enough for normal nutrient absorption leading to malabsorption. The substantial weight loss may lead dramatic improvement, and even complete remission of many of the obesity-related co-morbidities. Long-term data shows that the OAGB may result in a slightly higher weight loss and better resolution of diabetes than the RYGB. The superior diabetes remission rate in OAGB might be attributed to both the greater weight loss and the longer by-passed limb.

The OAGB has few long term complications. Less than 5% of the patients may require revision surgery, with half of the revisional surgeries due to severe malnutrition and the other half due to bile reflux, ulcer and/or weight regain.

1. Is technically a more complex operation than the AGB or LSG and potentially could result in greater complication rates.
2. Can lead to long-term vitamin/mineral deficiencies particularly deficits in vitamin B12, iron, calcium, and folate.
3. Generally has a longer hospital stay than the AGB.
4. Requires adherence to dietary recommendations, life-long vitamin/mineral supplementation, and follow-up compliance.