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What is gastric bypass surgery?​

Gastric bypass surgery shrinks the size of your stomach so you cannot eat as much as you used to, helping you lose weight. The surgeon will reroute or bypass part of your digestive system so you do not absorb as much food.


What are the risks of gastric bypass surgery?

Risks of bypass surgery include:

  • Gastritis (inflamed stomach lining), heartburn or stomach ulcers
  • Injury to the stomach, intestines or other organs during surgery
  • Leaking from the line where parts of the stomach have been stapled together
  • Poor nutrition
  • Scarring inside your belly that could lead to a blockage in your bowel in the future
  • Vomiting from eating more than your stomach pouch can hold


Why is the procedure 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; it will drastically change your lifestyle. After this surgery, you must eat healthy foods, control portion sizes of what you eat and exercise. If you do not follow these measures, you may have complications from the surgery and poor weight loss.

Always discuss the benefits and risks with your surgeon.


Before the procedure

Your surgeon will ask you to have tests and visits with other physicians before you have this surgery. Some of this include:

  • A complete physical exam
  • Blood tests, ultrasound of your gallbladder and other tests to make sure you are healthy enough to have surgery
  • Visits with your physician to make sure other medical problems you may have, such as diabetes, high blood pressure, and heart or lung problems are under control.
  • Nutritional counseling
  • Classes to help you learn what happens during the surgery, what you should expect after the surgery and what risks or problems may occur
  • You may want to visit with a counselor to make sure you are emotionally ready for this surgery; you must be able to make major changes in your lifestyle after the procedure.

If you smoke, you should quit several weeks before your surgery, and do not start smoking again after. Smoking slows recovery and increases the risks for problems. 

Tell your surgeon

  • If you are pregnant or think you might be pregnant
  • What medications you are taking including over-the-counter and prescriptions, vitamins, herbs and other supplements


On the day of surgery:

  • Follow instructions about when to stop eating and drinking
  • Take the medicines the physician gives you with a small sip of water


After the procedure

Most patients stay in the hospital for 1 to 4 days after surgery

In the hospital:

  • You’ll be asked to sit on the side of the bed and walk a little on the day you’ve had surgery.
  • You may have a catheter that goes through your nose into your stomach for 1 or 2 days to help drain fluids from your intestine.
  • You may have a catheter in your bladder to remove urine.
  • You will not be able to eat for the first 1 to 3 days; after that, you’ll have liquids and pureed or soft foods.
  • You may have a tube connected to the larger part of your stomach that was bypassed; the catheter will come out of your side and will drain fluids.
  • You’ll wear special stockings on your legs to help prevent blood clots from forming.
  • You’ll receive shots of medication to prevent blood clots.
  • You’ll receive pain medication either by pill form or through an IV inserted into your arm or hand.