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Gastric bypass surgery

Gastric bypass is surgery that is done to help you lose weight. After the surgery, you will not be able to eat as much as before, and your body will not absorb all the calories from the food you eat.

See also: Laparoscopic gastric banding

Description

This surgery helps you lose weight by changing how your stomach and small intestine handle the food you eat.

You will receive general anesthesia before this surgery. This will make you unconscious and unable to feel pain.

Gastric bypass can be done in 2 ways. In open surgery, your surgeon will make a large incision (cut) to open up your belly. Your surgeon will do the bypass by directly handling your stomach, small intestine, and other organs.

Another way to this surgery is to use a tiny camera, called a laparoscope, which is placed in your belly. This is called laparoscopy. In this surgery:

Laparoscopy may not be safe for you if you:

There are 2 basic steps during both kinds of gastric bypass:

This surgery takes about 4 hours.

This surgery may increase your risk for gallstones. Your doctor may recommend having a cholecystectomy (surgery to remove your gallbladder) before your bypass surgery.

Why the Procedure is Performed

Weight loss surgery may be an option if you are very obese and have not been able to lose weight through diet and exercise.

Gastric bypass surgery is not a "quick fix" for obesity. You must be committed to diet and exercise because you must continue dieting and exercising after the surgery. You may have complications from the surgery if you don’t. One problem some people have is throwing up if they eat more than their new small stomach can hold.

People who have this surgery should be mentally stable and not be dependent on alcohol or illegal drugs.

This procedure may be recommended for you if you have:

Risks

Gastric bypass is major surgery and has many risks. Some of these risks are very serious. You should discuss these with your surgeon.

The risk of the surgery itself or for problems after surgery may be greater than normal if you are:

Risks for any anesthesia are:

Risks for any surgery are:

Risks or problems that may occur during or soon after gastric bypass surgery are:

The risks or problems of weight-loss surgery that may occur over time are:

Before the Procedure

Your surgeon will ask you to have tests and visits with your other health care providers before you have this surgery. Some of these are:

If you are a smoker, you should stop smoking several weeks before surgery and not start smoking again after surgery. Smoking slows recovery and increases the risks of problems. Tell your doctor or nurse if you need help quitting.

Always tell your doctor or nurse:

During the week before your surgery:

On the day of your surgery:

After the Procedure

Most people stay in the hospital for 3 to 5 days after surgery. In the hospital, you:

You will be able to go home when you:

Outlook (Prognosis)

Most people lose about 10 to 20 pounds a month in the first year after surgery. Weight loss will decrease over time, so sticking to your diet and exercise early on will provide the largest weight loss. You may lose half or more of your extra weight in the first 2 years. You will lose weight most quickly just after surgery, when you are still on a liquid diet or pureed diet.

Losing enough weight after surgery can improve many medical conditions you might also have. Conditions that may improve are asthma, type 2 diabetes, high blood pressure, obstructive sleep apnea, high cholesterol, and gastroesophageal disease (GERD).

Weighing less should also make it much easier for you to move around and do your everyday activities.

Bypass surgery alone is not a solution for weight loss. It can train you to eat less, but you still have to do much of the work. To lose weight and avoid complications from the procedure, you will need to follow the exercise and eating guidelines that your doctor and dietitian gave you.

Alternative Names

Bariatric surgery - gastric bypass; Roux-en-Y gastric bypass; Gastric bypass - Roux-en-Y

References

Buchwald H, Estok R, Fahrbach K, Banel D, Sledge I. Trends in mortality in bariatric surgery: a systematic review and meta-analysis. Surgery. 2007;142:621-632.

Leslie D, Kellogg TA, Ikramuddin S. Bariatric surgery primer for the internist: keys to the surgical consultation. Med Clin North Am. 2007;91:353-381.

Townsend Jr. CM, Beauchamp RD, Evers BM, Mattox KL. Sabiston Textbook of Surgery. 18th ed. Philadelphia, Pa: Saunders; 2008.

Update Date: 2/12/2009

Updated by: Crystine Lee, MD, Department of Surgery, Marin General Hospital, Greenbrae, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.


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