Roux-en-Y Gastric Bypass (RnY)

The Roux-en-Y (RnY) gastric bypass has been considered the ”gold standard” operation for weight loss for decades. The gastric bypass involves creating a small pouch from the stomach and connecting this new
pouch directly to the small intestine via two joins. This serves two purposes: to restrict the amount of food
you eat because you will feel full very quickly and to reduce the amount of calories and nutrients
your body absorbs.
This type of surgery is often considered for patients who have pre-existing severe reflux
(GORD).
The main difference between this type of gastric bypass and omega loop gastric bypass is that two
anastomoses (joins) are made instead of one. This can make the surgery technically demanding in the severely obese. However the incidence of reflux afterwards is much lower in the RnY bypass compared with the Omega Loop gastric bypass. 

Weight loss is comparable between the two. The risk of bowel twist or blockage (small bowel obstruction) is 1-2% in the RnY group compared with very few reported cases in the Mini bypass group. 

Weight loss is excellent with patients losing 80-90% of their excess weight in 2 years.