Combined Restrictive/Malabsorptive Operation: Roux-en-Y Gastric Bypass

This operation, which is the procedure of choice of 85% of people, is an effective treatment for most patients with serious obesity. This operation is meant to help you restrict how much food you eat at one time, by giving you a sense of "satiety" with a small meal. Satiety is the signal that your stomach sends to your brain when it has stretched due to food. Your brain interprets this signal as a sense of "satisfaction," "fullness," or that you've "had enough." Once you have received this signal, you need to make a conscious choice that since you feel that way, that it is time to stop eating.

Most people say that this restored sense of satiety is a major change for them. Many obese people simply do not have satiety, and therefore may overeat. If this is the main cause of your overeating, a restrictive procedure is a very good choice for you. By restoring the natural feedback from your stomach to your brain, you will eat a smaller quantity yet not feel deprived. Many people say, "If I could eat smaller portions, I wouldn't have a problem!" The difference between a "diet" where you might eat smaller portions, and a gastric bypass is that you have a source of satisfaction with the smaller portion. Diets generally do not provide this positive reinforcement, and therefore often fail.

How Your Anatomy Is Changed
After food moves into the little pouch at the top of the stomach, it will "drain" out into the small intestine that is connected to the pouch. The opening from the pouch to the small intestine is small -- usually about 1/2 inch in size. It is made deliberately small, so that the pouch empties slowly. If the pouch empties very rapidly, one may not feel a strong sense of satiety with a little meal. The food travels down this piece of small intestine, called the "Roux limb", and about 30 inches from the pouch, meets the rest of the small intestine. At this point, digestive enzymes from the old "remnant" stomach, liver (bile), and pancreas mix with food, allowing it to be broken down and absorbed.

The separation of food from digestive enzymes for a length of small intestine means that for that distance, complex nutrients like carbohydrates, fats, and proteins can't be broken down into the small pieces needed for absorption. This separation provides the "malabsorptive" portion of this operation. This is a more minor contribution to weight loss in this procedure compared with restriction.

The Operative Procedure
This operation can be performed laparoscopically (through six small incisions), and is done so in about 95% of patients in our practice. Sometimes this operation can only be done through a large incision. See our section about methods of operations for more information. Your surgeon will create the small pouch out of the top of the stomach, and divide it from the larger "remnant" stomach. Next, the small intestine measured for a certain distance, and divided. One end is connected to the stomach pouch, to serve as a passage for food, called the "Roux limb". The other end is attached 30 to 60 inches down the Roux limb, to allow digestive enzymes to mix with the food here.

The connection between the stomach pouch and the Roux limb of small intestine is called the "stoma" or "anastomosis." This opening is made deliberately small -- about 1/2 inch in size -- so that your pouch empties slowly. Some surgeons believe that reinforcing this stoma is important to prevent late stretching or dilation of the stoma; this might allow faster pouch emptying. The reinforcement is done by taking a piece of strong connective tissue called "fascia" from another part of your body. If your operation is done laparoscopically, your surgeon may use fascia lata, a tight covering of your outer thigh. This is harvested by making an additional incision on your thigh. If you have an open operation, this strip of fascia may be taken from your abdominal wall with no additional incision.

Results
This operation has very good results in helping relieve obesity-related conditions. High blood pressure, high cholesterol, sleep apnea, diabetes, joint pains, and other illness can improve in a large number of patients. Since most people have obesity surgery to improve their health, this is one of the ways we measure success. In terms of weight loss, most people lose about 70% of the excess weight they carry at about one year after surgery. Over five to ten years, many people adapt to the restrictive elements, and can regain a small amount of weight. At 10 years, most people have maintained 66% of their excess weight.