Why a Mini-gastric bypass?

Most people have heard of a gastric bypass – more usually called “stomach stapling” – but few are aware that there are actually two types of bypass surgery, rather than one.

The standard bypass (also called Roux-en-Y) was developed in the US by Dr Edward Mason. in the 1960’s and remained the “gold-standard” procedure for decades. But in recent years, a new operation, called the mini-gastric bypass (MGB), has dramatically increased in popularity. It was developed by Dr Robert Rutledge in the late 1990’s and today it is rapidly becoming the preferred option by many bariatric surgeons. But why is that?

As with the standard Roux-en-Y version, the MGB essentially involves “re-plumbing” the stomach and small bowel so that the volume of food you can eat is much less. It also changes gut hormones in such a way that you effectively lose your appetite and no longer have the same craving for sweet or fatty foods. In Roux-en-Y bypass the bowel is cut through (divided) and then re-attached to the stomach and small bowel in two places (anastomoses), whereas in MGB the bowel is not actually divided and there is only one anastomosis. Because it is technically easier, MGB is a quicker procedure (about 50 minutes less than traditional bypass) and has a lower risk of complications. See here: https://www.bariatricsurgery.ie/mini-gastric-bypass/

One of the reasons why the MGB had a lot of critics following its introduction, is the theoretical risk that digestive juices can reflux up into the small stomach remnant, causing ulceration, inflammation and heartburn (called bile-acid reflux). However, recent studies suggest that this is not a major problem in practice and there are technical approaches to the surgery that can reduce the risk of this complication to a minimum. Most individuals who are suitable for RYGBP, would do just as well with MGB, though very occasionally there may be reasons to prefer RYGBP.

There are other advantages of MGB:

1) The risk of an internal hernia – a recognized complication of Roux-en-Y bypass – is reduced to almost zero with MGB.

(2) Long-term weight loss with MGB is at least as good as with RYGBP – in some studies even better.

(3) The health benefits of MGB are at least as good as with RYGBP.

(4) MGB is relatively easy to reverse. This is not the case with RYBP, where reversal is possible but technically demanding (and rarely done).

For all these reasons, there seems little doubt that the strong trend towards MGB will accelerate in the coming years.

Dr David Ashton MD Ph