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Gastric bypass surgery

How it works

Gastric bypass is surgery to help with weight loss. It helps you lose weight by changing how your stomach and small intestine handle the food you eat.

  • After surgery, your stomach pouch will be much smaller.
  • You will feel full or satisfied with much less food.
  • The food you eat will no longer go into the bottom portion of your stomach and the first part of the small intestine that break down food. This surgery is also called Roux-en-Y gastric bypass.

What happens during surgery?

This surgery takes about 2 hours.

  • Your stomach is divided with staples into 2 parts.
  • The first part is very small, about the size of a golf ball. This small stomach is called the pouch. The second part of the stomach is much bigger, but food cannot go into it.
  • The small intestine is connected to the small pouch to re-route food around the big stomach.
  • The pouch can hold only a small amount of food, so if you eat too much or too fast you will throw up or have pain.

Laparoscopic surgery

Most of the time, the surgery is done using a tiny camera that is placed in your belly. This type of surgery is called laparoscopy. The camera allows your surgeon to see inside your belly. In this surgery:

  • Your surgeon will make 5 to 6 small incisions (cuts) in your belly.
  • Through these small cuts, the surgeon will place a camera and the instruments to perform the surgery.
  • The camera is connected to a TV monitor, and the surgeon can see inside your belly.

Open surgery

Sometimes, the surgeon will not be able to perform the surgery through a small incision and will need to make a large surgical cut (incision) to open up your belly.

The most common reason that you may need open surgery is if you have had many abdominal surgeries in the past. This is because you may have scar tissue (adhesions) from the earlier surgeries.

A large surgical cut will:

  • Be more painful
  • Keep you in the hospital longer
  • Have a longer recovery time
  • Have a greater chance of infection in the wound
  • Have a greater chance of a hernia in the wound

What to expect after surgery

You may be able to go home the day after a laparoscopic gastric bypass. If you are diabetic, or have blood pressure problems, you may need to stay another day.

Most people stay in the hospital for 2 days after open surgery.

Although not likely, you may have a drain (tube) coming from your belly. It will come out of your side and will drain fluids that build up in your belly. The drain tube will usually be removed before you leave the hospital.

You may need to take off work for about 3 weeks. However, if your job does not involve too much physical activity, you may be able to return to work if sooner.

Your health care providers can talk with you about how eating and other parts of your life will change after this surgery.

Things to consider

Here are some things you should know about this type of surgery:

  • Recovery after gastric bypass is usually more difficult if open surgery is done.
  • Taking NSAID's such as ibuprofen or naproxen might produce an ulcer at the connection of the small bowel to the gastric pouch. If you need to take these kinds of medicines on a regular basis, a sleeve gastrectomy might be better for you.
  • Smoking can cause ulcers in the gastric pouch which won't heal. It is very important not to smoke after having a gastric bypass.
  • Alcohol is more quickly absorbed after a gastric bypass, and you may feel the effects much more quickly, even after a small amount of alcohol.
  • After surgery, your body may not absorb important vitamins and minerals such as iron, calcium, vitamin B12, and others. To avoid problems such as brittle bones (osteoporosis) and low blood count (anemia), you will need to take vitamin supplements for the rest of your life. Many people need to eat red meat in order to prevent anemia.
  • In order to prevent weight regain after gastric bypass surgery, you will need to follow a diet and exercise program for the rest of your life.
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Review Date: 1/30/2018

Reviewed By: John E. Meilahn, MD, Bariatric Surgery, Chestnut Hill Surgical Associates, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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