Surgery Medical Encyclopedia Health Navigator Drug Interactions Drug Notes Health Capsules Smart Sites Back Pain Hip Pain Knee Pain Weight Loss Gastric bypass surgery Bariatric surgery - gastric bypass; Roux-en-Y gastric bypass; Gastric bypass - Roux-en-Y Definition 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. Description You will have general anesthesia before this surgery. You will be asleep and pain-free.There are two steps during gastric bypass surgery:The first step makes your stomach smaller. Your surgeon will use 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 of food. Because of this you will eat less and lose weight.The second step is the bypass. Your surgeon will connect 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 will make a large surgical cut to open up your belly. Your surgeon will do the bypass by working on your stomach and small intestine.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.In this surgery:First, your surgeon will make 4 to 6 small cuts in your belly.Then your surgeon will pass the laparoscope through one of these cuts. It will be connected to a video monitor in the operating room. Your surgeon will look at the monitor to see inside your belly.Your surgeon will use thin surgical instruments to do your bypass. These instruments will be inserted through the other cuts. The gastric bypass is the same whether you have open or laparoscopic surgery.Advantages of laparoscopy over open surgery include:Shorter hospital stay and quicker recoveryLess painSmaller scars and a lower risk of getting a hernia or infectionThis surgery takes about 2 to 4 hours. Why the Procedure Is Performed Weight-loss surgery is only recommended if you cannot lose a large amount of weight and keep it off by dieting, changing your behavior, and exercising alone.Doctors often use the body mass index (BMI) and health conditions such as type 2 diabetes and high blood pressure to determine which patients are most likely to benefit from weight-loss surgery.Gastric bypass surgery is not a "quick fix" for obesity. You must diet and exercise after surgery. You also need to know about the risks of surgery, and what your life will be like after the surgery. Risks Gastric bypass is major surgery and it has many risks. Some of these risks are very serious. You should discuss these with your surgeon. Risks for any surgery or anesthesia include:Allergic reactions to medicinesBlood clots in the legs that may travel to your lungsBlood lossBreathing problemsHeart attack or stroke during or after surgeryInfection, including in the cut, lungs (pneumonia), bladder, or kidney There are a number of risks for any weight-loss surgery. There are also risks that are more likely after gastric bypass surgery. These include blockage of the stomach or intestine (obstruction) and infection inside the abdomen. Before the Procedure Your surgeon will ask you to have tests and visits with other health care providers before you have this surgery.If you are a smoker, you should stop smoking several weeks before surgery and should not start smoking again after surgery. Smoking slows recovery and increases the risk of problems. Tell your doctor or nurse if you need help quitting.Always tell your doctor or nurse:If you are or might be pregnantWhat drugs, vitamins, herbs, and other supplements you are taking, even ones you bought without a prescription During the week before your surgery:You may be asked to stop taking aspirin, ibuprofen (Advil, Motrin), vitamin E, warfarin (Coumadin), and any other drugs that affect your blood's ability to clot.Ask your doctor which drugs you should still take on the day of your surgery.Prepare your home for after the surgery. After the Procedure Most people stay in the hospital for 3 to 5 days after surgery.In the hospital:You will be asked to sit on the side of the bed and walk a little on the same day you have surgery.You may have a (tube) catheter that goes through your nose into your stomach for 1 or 2 days. This tube helps drain fluids from your stomach.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 can have liquids and then pureed or soft foods.You may have a catheter connected to the larger part of your stomach that was bypassed. The catheter will come out of your side and will drain fluids.You will wear special stockings on your legs to help prevent blood clots from forming.You will receive shots of medicine to prevent blood clots.You will receive pain medicine. You will take pills for pain or receive pain medicine through an IV (a catheter that goes into your vein). You will be able to go home when:You can eat liquid or pureed food without vomiting.You can move around without a lot of pain.You do not need pain medicine through an IV or given by shot. Outlook (Prognosis) Most people lose about 10 to 20 pounds a month in the first year after surgery. Weight loss will decrease over time. Sticking to your diet and exercise plan will help you lose more weight.You may lose half or more of your extra weight in the first 2 years. You will lose weight quickly after surgery if you are still on a liquid or pureed diet.Losing enough weight after surgery can improve many medical conditions, including:AsthmaGastroesophageal reflux disease (GERD)High blood pressureHigh cholesterolObstructive sleep apneaType 2 diabetesWeighing less should also make it much easier for you to move around and do your everyday activities.To lose weight and avoid complications from the procedure, you will need to follow the exercise and eating guidelines that your doctor and dietitian have given you. Open References References Gloy VL, Briel M, Bhatt DL, Kashyap SR, Schauer PR, Mingrone G, et al. Bariatric surgery versus non-surgical treatment for obesity: a systematic review and meta-analysis of randomised controlled trials. BMJ. 2013;347:f5934.Messier SP, Mihalko SL, Legault C, Miller GD, Nicklas BJ, DeVita P, et al. Effects of intensive diet and exercise on knee joint loads, inflammation, and clinical outcomes among overweight and obese adults with knee osteoarthritis: the IDEA randomized clinical trial. JAMA. 2013;310(12):1263-73.Mingrone G, Panunzi S, De Gaetano A, et al. Bariatric surgery versus conventional medical therapy for type 2 diabetes. N Engl J Med. 2012 Apr 26;366(17):1577-85.Richards WO. Morbid Obesity. In: Townsend Jr. CM, Beauchamp RD, Evers BM, Mattox KL. Sabiston Textbook of Surgery. 19th ed. Philadelphia, PA: Elsevier Saunders; 2012; chap 15.Schauer PR, Kashyap SR, Wolski K, et al. Bariatric surgery versus intensive medical therapy in obese patients with diabetes. N Engl J Med. 2012 Apr 26;366(17):1567-76. Roux-en-Y stomach surgery for weight loss Illustration Roux-en-Y stomach surgery for weight loss The Roux-en-Y gastric bypass procedure involves creating a stomach pouch out of a small portion of the stomach and attaching it directly to the small intestine, bypassing a large part of the stomach and duodenum. Not only is the stomach pouch too small to hold large amounts of food, but by skipping the duodenum, fat absorption is substantially reduced. Adjustable gastric banding Illustration Adjustable gastric banding Restrictive gastric operations, such as an adjustable gastric banding procedure, serve only to restrict and decrease food intake and do not interfere with the normal digestive process.In this procedure, a hollow band made of special material is placed around the stomach near its upper end, creating the small pouch and a narrow passage into the larger remaining portion of the stomach. This small passage delays the emptying of food from the pouch and causes a feeling of fullness.The band can be tightened or loosened over time to change the size of the passage. Initially, the pouch holds about 1 ounce of food and later expands to 2-3 ounces. Vertical banded gastroplasty Illustration Vertical banded gastroplasty Restrictive gastric operations, such as vertical banded gastroplasty (VGB), serve only to restrict and decrease food intake and do not interfere with the normal digestive process.In this procedure the upper stomach near the esophagus is stapled vertically to create a small pouch along the inner curve of the stomach. The outlet from the pouch to the rest of the stomach is restricted by a band made of special material. The band delays the emptying of food from the pouch, causing a feeling of fullness. Biliopancreatic diversion (BPD) Illustration Biliopancreatic diversion (BPD) Malabsorptive operations, such as biliopancreatic diversion (BPD), restrict both food intake and the amount of calories and nutrients the body absorbs.In a BPD procedure, portions of the stomach are removed. The small pouch that remains is connected directly to the final segment of the small intestine, completely bypassing the upper part of the small intestines. A common channel remains in which bile and pancreatic digestive juices mix prior to entering the colon. Weight loss occurs since most of the calories and nutrients are routed into the colon where they are not absorbed. Biliopancreatic diversion with duodenal switch Illustration Biliopancreatic diversion with duodenal switch Malabsorptive operations restrict both food intake and the amount of calories and nutrients the body absorbs.In this procedure, a larger portion of the stomach is left intact, including the pyloric valve that regulates the release of contents from the stomach into the small intestine. The duodenum is divided near this valve, and the small intestine divided as well. The portion of the small intestine connected to large intestine is attached to the short duodenal segment next to the stomach. The remaining segment of the duodenum connected to the pancreas and gallbladder is attached to this limb closer to the large intestine. Where contents from these two segments mix is called the common channel, which dumps into the large intestine. Dumping syndrome Illustration Dumping syndrome Dumping syndrome occurs when the contents of the stomach empty too quickly into the small intestine. The partially digested food draws excess fluid into the small intestine causing nausea, cramping, diarrhea, sweating, faintness, and palpitations. Dumping usually occurs after the consumption of too much simple or refined sugar in people who have had surgery to modify or remove all or part of the stomach. Self Care Your diet after gastric bypass surgery Weight-loss surgery and children Related Information Body mass index Obstructive sleep apnea Type 2 Diabetes Coronary heart disease Laparoscopic gastric banding Review Date: 05/08/2014 Reviewed By: Joshua Kunin, MD, Consulting Colorectal Surgeon, Zichron Yaakov, Israel. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.