What is gastric bypass weight-loss surgery?

Roux-en-Y gastric bypass (RYGB) is a type of weight-loss surgery. Weight-loss surgery is also called bariatric surgery. It’s often done as a laparoscopic surgery, with small incisions in the abdomen.

This surgery reduces the size of your upper stomach to a small pouch about the size of an egg. The surgeon does this by stapling off the upper section of the stomach. This reduces the amount of food you can eat. The surgeon then attaches this pouch directly to part of the small intestine called the Roux limb. This forms a “Y” shape. The food you eat then bypasses the rest of the stomach and the upper part of your small intestine. This reduces the amount of fat and calories you absorb from the foods you eat. It also reduces the amount of vitamins and minerals you absorb from food.

Why might I need gastric bypass weight-loss surgery?

Gastric bypass surgery is used to treat severe obesity. It’s advised for people who have tried other weight loss methods, such as diet and exercise, without long-term success. Your doctor may advise gastric bypass surgery if you are severely obese with a body mass index (BMI) over 40. Your doctor may also advise it if you have a BMI between 35 and 40 and a health condition such as sleep apnea, high blood pressure, heart disease, or type 2 diabetes.

Gastric bypass can help a person lose about 100 pounds of excess weight. It may also improve, or in some cases even reverse type 2 diabetes. It can also improve or stop heartburn and reflux. Weight-loss surgery can also lower the risk for high blood pressure or improve it for people that already have it. A gastric bypass can also help with sleep apnea, and certain other health problems such as high cholesterol.

What are the risks of gastric bypass weight-loss surgery?

Bleeding, infection, and blood clots in your legs are possible side effects that may occur after any surgery. General anesthesia may also cause breathing problems or other reactions. You may also have leaks from the stomach pouch or the Roux limb.

Possible problems over time may include: 

• Low levels of vitamins if you don’t take supplements daily for the rest of your life (in some cases, even if you do take supplements)

• Low levels of iron and calcium

• Trouble getting enough protein

• Dumping syndrome. This can cause nausea, fast heartbeat, belly (abdominal) cramping or pain, fainting, and diarrhea after eating.

• Narrowing of the sites where intestines are joined (stenosis or stricture)

• Dangerous internal hernia, in which the small intestine can be trapped and blocked

• Hernia at the port sites

• Poor healing of the incision sites

• Need for additional surgery 

• Failure to lose enough weight

• Weight regain, if you snack on high-calorie foods and don’t exercise

• Loss of too much weight too quickly. This can cause sagging skin that may need to be removed surgically.

• Gallstones. This requires surgery to remove the gallbladder. 

You may have other risks based on your health. Make sure to talk with your healthcare team about any concerns before the surgery.

How do I get ready for Roux-en-Y gastric bypass surgery?

Your healthcare team will need to make sure that gastric bypass surgery is a good option for you. Weight-loss surgery isn’t advised for people who abuse medicines or alcohol, or who are not able to commit to a lifelong change in diet and exercise habits.

Before having surgery, you’ll need to enroll in a bariatric surgery education program. This will help you prepare for surgery, and life after surgery. You’ll have nutritional counseling. And you may have a psychological evaluation. You’ll also need physical exams and tests such as an electrocardiogram (ECG), a chest X-ray, and sleep study. You will need blood tests. You may have imaging studies of your stomach, or have an upper endoscopy. 

If you smoke, you will need to stop several months before surgery. Your surgeon may ask you to lose some weight before surgery. This will help make your liver smaller, and make surgery safer. You’ll need to stop taking aspirin, ibuprofen, and other blood-thinning medicines in the days before your surgery. You shouldn’t eat or drink anything after midnight before surgery.

What happens during Roux-en-Y gastric bypass surgery?

• The surgery usually takes several hours.

• You will have general anesthesia for your surgery. This will cause you to sleep through the surgery, and not feel pain.

• Your surgeon may use laparoscopy. They will make several small cuts (incisions) in your abdomen. The surgeon will then insert a laparoscope and put small surgery tools into these incisions.

• The surgeon will use a laparoscopic stapler to make a small stomach pouch with the upper part of your stomach.

• The surgeon then uses the stapler to divide the upper part of your small intestine into a tube with two ends.

•  One end of the small intestine (the Roux limb) is brought up to the stomach pouch, and a small connection (anastomosis) is made between them. The other end of the small intestine is then connected to another part of the small intestine.

• Then your surgeon may test for leaks with a dye study or an upper endoscopy.

What happens after Roux-en-Y gastric bypass surgery?

You may stay in the hospital for 1 to 2 days after the surgery. Talk with your doctor about wound care, safe pain medicines, and when you can start physical activity. Your doctor will tell you how often to change the dressing on your incision. 

Tell your doctor right away if you have any of the below:

• Fever

• Your wound becomes painful or hot to the touch or leaks fluid

• Coughing or trouble breathing

• Vomiting and diarrhea

• Blood in your bowel movement

• Pain in the abdomen, chest, shoulder, or legs

• Any other problems or symptoms

You will likely only have liquids for the first 1 to 2 weeks after surgery. Your doctor may slowly add soft food and then regular food to your diet about a month after surgery. You will be need to chew slowly and fully, and not to drink 30 minutes before or after you eat.

Your initial weight-loss may occur quickly, so it's important to get all of the nutrition and vitamins you need as you recover. Your doctor will prescribe vitamin and mineral supplements that your body may no longer absorb well from food alone.

To prevent nutritional problems after gastric bypass surgery, many doctors advise:

• Daily multivitamins. You should take a daily multivitamin that contains 200% of the daily values.

• Daily calcium supplements. Multivitamins with calcium may not protect bone health. You may need 1,600 to 2,000 IU vitamin D and 1,600 mg calcium daily. Take a calcium supplement at least 2 hours after your multivitamin.

• Vitamin B-12 supplements. Doctors advise vitamin B-12 supplements for all people who have had weight-loss surgery to help prevent bone fractures. You can take this by mouth several times a week. Or you may have B-12 injections every month.

• Oral vitamin D supplements. You may need this if you have low levels. Your doctor may prescribe 50,000 IU of vitamin D taken by mouth once a week for 8 weeks. Some people need lifelong vitamin D supplements.

• Iron supplements. After gastric bypass surgery, the amount of iron in a multivitamin may not be enough to prevent anemia. You may need an additional 50 to 100 mg of elemental iron a day. Taking vitamin C will help your body absorb iron. Ask your doctor about the recommended dose for you.

Because nutritional deficiencies can happen after this surgery, experts recommend that your blood be tested at least every 6 months for the rest of your life to ensure that you are getting the right amount of vitamins and minerals. 

During weight-loss, you may have body aches, dry skin, mood changes, and temporary hair thinning, and feel tired and cold. As your weight stabilizes, these problems should go away. Weight loss continues for about a year, and then will stop. After a year, you may be able to eat more if the pouch stretches. You should use the first year to develop good eating and exercise habits that will keep you from regaining weight.

Along with follow-up appointments with your doctor and surgeon, you will likely see a dietitian who will teach you how and what to eat with your reduced stomach size. You may also need to see a psychologist to help you deal with the feelings and concerns over your changed lifestyle.

Next steps

Before you agree to the test or the procedure make sure you know:

• The name of the test or procedure

• The reason you are having the test or procedure

• What results to expect and what they mean

• The risks and benefits of the test or procedure

• What the possible side effects or complications are

• When and where you are to have the test or procedure

• Who will do the test or procedure and what that person’s qualifications are

• What would  happen if you did not have the test or procedure

• Any alternative tests or procedures to think about

• When and how you will get the results

• Who to call after the test or procedure if you have questions or problems

• How much you will have to pay for the test or procedure