What is a Gastric Bypass?
A Gastric Bypass surgery reduces the size of the stomach and the length of the
gastrointestinal tract. Therefore, the surgery is a combined restrictive and malabsorptive
procedure. The size of the stomach is reduced by almost 90%, forming a small pouch 15-30ml
in capacity from the upper part of the stomach.
How is the surgery performed?
Gastric bypass is performed under general anaesthesia using the laparoscopic technique. It
is the most minimally invasive approach. The surgeon will male a small pouch in the upper
stomach using metal staples, this pouch will hold the food. The stomach will be cut through
and the pouch will not be attached to the rest of the stomach.
The next step for the surgeon will be to cut your small intestine and divide it into two parts.
The lower part of the intestine will be attached to the small pouch (upper part of the
stomach). The food will now be able to travel from the small pouch to the lower part of the
The main (large) part of the stomach will be left in your abdomen. It will have a blood supply
and will still produce digestive juices, the surgeon will attach it further down to the small
intestine to allow the digestive juices to mix with the food.
How does it work?
As the size of the stomach is reduced by almost 90 %, the intake of food that is consumed in
one sitting is reduced significantly. Normally, food passes from the stomach into the small
intestine which absorbs major proportion of nutrients as well as calories. The remaining
food further passes into the large intestine. During the gastric bypass surgery, reduced
stomach is connected directly to the middle part of the small intestine, thus bypassing the
remaining gastric body and the upper part of the small intestine (duodenum). The
procedure shortens the “path” of food through the gastrointestinal tract, and therefore less
of it is absorbed.
Who is a good candidate for a Gastric Bypass?
1. BMI is 40 or higher
2. BMI is 35 or higher and client has a life threatening or disabling problem due to excess
The client needs to change lifestyle and follow post-operative recommendations
Most people lose weight quickly over the first year after having bypass surgery, normally
reaching their target weight after 18 months.
People lose 65–75% of their excess body weight. The key to achieving greater weight loss
and weight maintenance in long term is to follow regular exercise and eating regime.