Gastric Bypass Surgery
Gastric bypass is surgery that helps you lose weight by changing how your stomach and small intestine handle the food you eat.
After the surgery, your stomach will be smaller. You will feel full with less food.
The food you eat will no longer go into some parts of your stomach and small intestine that absorb food. Because of this, your body will not get all of the calories from the food you eat.
You will have general anesthesia before this surgery. You will be asleep and pain-free.
There are 2 steps during gastric bypass surgery:
- The first step makes your stomach smaller. Your surgeon uses staples to divide your stomach into a small upper section and a larger bottom section. The top section of your stomach (called the pouch) is where the food you eat will go. The pouch is about the size of a walnut. It holds only about 1 ounce (oz) or 28 grams (g) of food. Because of this you will eat less and lose weight.
- The second step is the bypass. Your surgeon connects a small part of your small intestine (the jejunum) to a small hole in your pouch. The food you eat will now travel from the pouch into this new opening and into your small intestine. As a result, your body will absorb fewer calories.
Gastric bypass can be done in two ways. With open surgery, your surgeon makes a large surgical cut to open your belly. The bypass is done by working on your stomach, small intestine, and other organs.
Another way to do this surgery is to use a tiny camera, called a laparoscope. This camera is placed in your belly. The surgery is called laparoscopy. The scope allows the surgeon to see inside your belly.
In this surgery:
- The surgeon makes 4 to 6 small cuts in your belly.
- The scope and instruments needed to perform the surgery are inserted through these cuts.
- The camera is connected to a video monitor in the operating room. This allows the surgeon to view inside your belly while doing the operation.
Advantages of laparoscopy over open surgery include:
- Shorter hospital stay and quicker recovery.
- Less pain.
- Smaller scars and a lower risk of getting a hernia or infection.
This surgery takes about 2 to 4 hours.
Guidelines to qualify for gastric bypass surgery
Gastric bypass and other weight-loss surgeries are major, life-changing procedures. While weight-loss surgery can help reduce your risk of weight-related health problems — such as type 2 diabetes, high blood pressure, heart disease and sleep apnea — it can also pose major risks and complications. You may need to meet certain medical guidelines to qualify for weight-loss surgery. You likely will have an extensive screening process to see if you qualify.
In general, gastric bypass or another weight-loss surgery could be an option for you if:
- Efforts to lose weight with diet and exercise have been unsuccessful
- Your body mass index (BMI) is 40 or higher
- Your BMI is 35 or more and you have a serious weight-related health problem, such as type 2 diabetes, high blood pressure or severe sleep apnea
- You're a teenager who's gone through puberty, your BMI is 35 or more, and you have serious obesity-related health problems, such as type 2 diabetes or severe sleep apnea
In some cases, you may qualify for certain types of weight-loss surgery if your BMI is 30 to 34 and you have serious weight-related health problems.
Why is Gastric Bypass Surgery Performed ?
Those who are severely overweight and cannot lose weight through diet and exercise may turn to gastric bypass surgery.
Undergoing gastric bypass surgery is a serious commitment to a healthier lifestyle — patients must:
- Greatly change their lifestyle.
- Learn to control portion sizes.
- Exercise regularly.
Doctors may perform this procedure on patients with a high Body Mass Index as well as obesity-related health conditions.
- You can expect to stay in the hospital for two to three days.
- The morning after your gastric bypass surgery, you will:
- Start a clear liquid diet for at least two weeks. It's very important that you drink at least 64 ounces of fluid every day to avoid becoming dehydrated.
- Begin to go for walks around your room and in the halls.
- Immediately before discharge, your bariatric surgery team will give you instructions on how to care for yourself at home, including:
- Incision and drainage care
- Pain control
- Vitamin supplements to get adequate amounts of vitamin B12, iron, and calcium
Benefits of Gastric Bypass Surgery
- Long-term weight loss: Many people who undergo gastric bypass surgery experience rapid weight loss following the procedure and continue to lose weight months and years later.
- Reducing or curing a variety of obesity-related illnesses, including diabetes, high blood pressure, and sleep apnea.
- Improved quality of life and mood: Many people who undergo gastric bypass surgery report a decrease in depression and anxiety, as well as improved self-esteem, sexual function, and social interactions.
Find out more about the benefits of weight-loss surgery.
Gastric Bypass Surgery Requirements
People who qualify for gastric bypass surgery include:
- Those with a Body Mass Index greater than or equal to 40, or who are more than 100 pounds overweight.
- Those with a Body Mass Index greater than or equal to 35 who have at least two obesity-related conditions. This could include: Type 2 Diabetes, hypertension, or heart disease, among others.
- Those who cannot achieve a healthy weight with diet and exercise.
Learn how to calculate your own Body Mass Index.
Dumping Syndrome and Other Gastric Bypass Surgery Risks
Dumping syndrome is a potential risk of gastric bypass surgery. It occurs when large volumes of food in the stomach move too quickly through the small intestine, frequently after eating sweet or high-fat foods.
Dumping syndrome can cause:
Other gastric bypass surgery risks and complications include:
- Perforation of stomach or intestines
- Leakage of surgical connection between the stomach and the intestine
- Internal bleeding or profuse bleeding of the surgical wound
- Gastric pouch/anastomotic obstruction or bowel obstruction
Your bariatric surgeon will review all potential gastric bypass surgery risks, complications, and other weight loss surgery options with you prior to your procedure. If you have any questions about gastric bypass surgery, we encourage you to ask your surgeon.
There are two components to the procedure. First, a small stomach pouch, approximately one ounce or 30 milliliters in volume, is created by dividing the top of the stomach from the rest of the stomach. Next, the first portion of the small intestine is divided, and the bottom end of the divided small intestine is brought up and connected to the newly created small stomach pouch. The procedure is completed by connecting the top portion of the divided small intestine to the small intestine further down so that the stomach acids and digestive enzymes from the bypassed stomach and first portion of small intestine will eventually mix with the food.
The gastric bypass works by several mechanisms. First, similar to most bariatric procedures, the newly created stomach pouch is considerably smaller and facilitates significantly smaller meals, which translates into less calories consumed. Additionally, because there is less digestion of food by the smaller stomach pouch, and there is a segment of small intestine that would normally absorb calories as well as nutrients that no longer has food going through it, there is probably to some degree less absorption of calories and nutrients.
Most importantly, the rerouting of the food stream produces changes in gut hormones that promote satiety, suppress hunger, and reverse one of the primary mechanisms by which obesity induces type 2 diabetes.
- Produces significant long-term weight loss (60 to 80 percent excess weight loss)
- Restricts the amount of food that can be consumed
- May lead to conditions that increase energy expenditure
- Produces favorable changes in gut hormones that reduce appetite and enhance satiety
- Typical maintenance of >50% excess weight loss
When should I consider gastric bypass surgery?
Gastric bypass surgery is the most effective type of surgery for weight loss, but it is not for everyone. Discuss with your doctor which approach is best for you, and talk about what to expect. You could ask:
- What's the average loss of weight after a year?
- What's the average loss of weight after five years?
- What's my role after surgery?
How do I prepare for gastric bypass surgery?
You are likely to need different tests to make sure that a gastric bypass is right for you.
Your doctor will advise you about any changes you need to make to medications and diet in the weeks or days before surgery.
What happens during gastric bypass surgery?
Gastric bypass surgery is performed while you are under general anaesthetic and will probably involve a hospital stay of 3 to 5 days.
The surgery is usually done as a keyhole procedure, but sometimes an open operation is needed.
During the procedure, staples are used to create a small pouch in the top part of your stomach, as the image below shows.
The pouch is attached by stitches to the lower part of your small intestine so food that you eat will bypass most of the stomach and the first part of the small intestine.
Less food will be absorbed into the body and you will feel full after eating only a small amount.