The most proximal portion of the small bowel is located and then measured approximately 50 cm distally where the jejunum is transected using an endoscopic stapler.

A connection between the stomach and the previously transected jejunum is made to create the Roux limb which will carry gastric contents from the newly created gastric pouch directly to the distal jejunum creating the bypass. There are many ways to create this connection using a variety of stapling devices or by laparoscopic suturing [2].

The jejunojejunostomy (JJ) is the connection between the Roux limb (which carries the pouch contents) and the biliopancreatic limb (which carries the remnant stomach contents). The point where this connection is made marks the end of the bypass. Prior to creating the jejunojejunostomy, the surgeon measures out between 75 and 150 cm of the jejunum. This is then determined to be the area where the JJ anastomosis will be created. The pieces of bowel are connected using staplers or sewing techniques similar to those used for the gastrojejunostomy.

There are several holes in the mesentery of the bowel which are created when making these connections. It is important to close these as it may be a potential site for bowel to slip through in the future, called an internal hernia. This can have devastating consequences including death of nearly all the small bowel.

The last step many surgeons perform is a leak test. The abdomen is filled with fluid and the gastrojejunostomy is submerged. An endoscope is placed in the stomach, and air is inflated to examine for occult leaks. If a leak is noted, it is repaired.

Once it is confirmed that there is no leak, the abdomen is inspected for any signs of bleeding, and the bowel is laid in appropriate anatomic position, the ports are removed, the pneumoperitoneum is released, and incisions are closed.