The gastric bypass or stomach bypass is one of the surgical techniques for treating morbid obesity. Alongside purely restrictive techniques, such as gastric banding, and largely malabsorptive techniques, such as Biliopancreatic Derivation by Scopinaro, this is a combined technique.
As with a purely restrictive intervention such as the adjustable gastric band, this surgery is largely a restriction of the food intake, with reduced digestion a less important factor. However, the long-term results are noticeably better than those for purely restrictive surgery. This is due to reduced food intake, a reduced feeling of hunger and the existence of “dumping”(a feeling of being unwell) when ingesting sugars.
Practically every case involves a laparoscopic operation or keyhole surgery. Via small incisions of 0.5 to 1 cm, the surgeon makes 5 to 7 trocarts (operating canals).
A small stomach pouch of about 15 ml is separated from the stomach and sealed with staples. With this technique the stomach and the small intestine are left intact! The small intestine is then cut 50 cm from the point at which it starts. The bottom part of the small intestine is then linked to the small stomach pouch. This can be done by means of staples or stitches. The top part of the small intestine is then rejoined to the other part about 100 cm from the stomach. The surgeon may decide to alter the length of these intestine segments.
As a result the stomach and duodenum are bypassed, so that food no longer passes through the stomach. The food does not mix with gastric, gall and pancreas juices until it reaches the point where the 2 small intestine loops meet each other.
The gastric bypass largely works through reduced food intake (restriction). This is achieved in several ways.