Surgery Overview

Gastric bypass surgery makes the stomach smaller and causes food to bypass part of the small intestine. You will feel full more quickly than when your stomach was its original size. This reduces the amount of food you can eat at one time. Bypassing part of the intestine reduces how much food and nutrients are absorbed. This leads to weight loss.

One type of gastric bypass surgery is a Roux-en-Y gastric bypass.

In normal digestion, food passes through the stomach and enters the small intestine, where most of the nutrients and calories are absorbed. It then passes into the large intestine (colon), and the remaining waste is eventually excreted.

In a Roux-en-Y gastric bypass, only a small part of the stomach is used to create a new stomach pouch, roughly the size of an egg. The smaller stomach is connected directly to the middle portion of the small intestine (jejunum), bypassing the rest of the stomach and the upper portion of the small intestine (duodenum).

This procedure can be done by making a large incision in the abdomen (an open procedure) or by making a small incision and using small instruments and a camera to guide the surgery (laparoscopic approach).

See a picture of a Roux-en-Y gastric bypass.

What To Expect After Surgery

You will have some belly pain and may need pain medicine for the first week or so after surgery. The cut that the doctor makes (incision) may be tender and sore. Because the surgery makes your stomach smaller, you will get full more quickly when you eat. Food also may empty into the small intestine too quickly and lead to dumping syndrome. This can cause diarrhea and make you feel faint, shaky, and nauseated. It also can make it hard for your body to get enough nutrition.

Your doctor will give you specific instructions about what to eat after the surgery. For about the first month after surgery, your stomach can only handle small amounts of soft foods and liquids while you are healing. It is important to try to sip water throughout the day to avoid becoming dehydrated. You may notice that your bowel movements are not regular right after your surgery. This is common. Try to avoid constipation and straining with bowel movements.

Bit by bit, you will be able to add solid foods back into your diet. You must be careful to chew food well and to stop eating when you feel full. This can take some getting used to, because you will feel full after eating much less food than you are used to eating. If you do not chew your food well or do not stop eating soon enough, you may feel discomfort or nausea and may sometimes vomit. If you drink a lot of high-calorie liquid such as soda or fruit juice, you may not lose weight. If you continually overeat, the stomach may stretch. If your stomach stretches, you will not benefit from your surgery.