Roux-en-Y Gastric Bypass
The Gastric Bypass is the operation we perform most often and is widely considered the gold standard in bariatric surgery. It is estimated that over 200,000 of these procedures are performed every year in the US. Gastric bypass involves placing a row of staples across the stomach, using a special surgical instrument, to create a self-contained pouch of about 15 cc (one tablespoon) in volume. The stomach is positioned within the surgical stapler instrument and as the jaws are closed, it squeezes the two walls of the stomach together. At that point, six parallel rows of staples are “fired” through both walls of the stomach to connect them, closing off the larger portion of the stomach. We then cut between the rows of staples, separating the stomach into two separate, distinct parts. This allows each part to heal separately, and to prevent the possibility of the staples line coming apart in the future. The second part of the operation involves a very small opening that is made in the pouch and is connected to a section of small intestine, allowing a small amount of food to pass.
How the Gastric Bypass Works
Gastric bypass surgery has been shown to produce greater and more sustained weight loss than other operations. It does this in four ways:
- First, the amount of solid food that you can eat is restricted by the size of the pouch
- Secondly, the small opening into the small intestine slows the flow of food out of the pouch.
- Third, up to 150 centimeters of small intestine is bypassed and therefore rendered “non-absorptive” due to the lack of bile, pancreatic juices, and food not being present at the same place to allow absorption of calories.
- And fourth, solid sugar containing food such as cake, candy, ice creams, and some colas, will produce a temporary, unpleasant “illness” called Dumping Syndrome. The Dumping Syndrome is caused by a concentration of sugars in the small intestines and produces nausea, tremors, chills, sweating, palpitations, and diarrhea. It will last from one to four hours. Sugars are high in calories, and will lead to weight gain. The dumping syndrome will discourage you from making these poor food choices.
- After surgery, you will only be able to eat about one ounce of food at a time. Even though your body has enough fat stores to keep you going for six months or more, you would not want to continue this consumption rate for too long. Over the course of a year, the small pouch will stretch a great deal, and you will find yourself able to eat more. However, do not think you will then be able to eat as much as you want. You will never again be able to eat as much as you can now. You will also need to take vitamin and mineral supplement forever.
Gastric bypass patients have the potential to lose more weight than with any other bariatric surgery procedure. This is due to the combination of restriction and malabsorption. Studies have shown that the average gastric bypass patient loses over 60% of their excess body weight.1 Evidence from our program shows a much higher excess body weight loss on average.
Other significant benefits include:
- Resolution of type-2 diabetes: Over 80%
- Improvement of High Cholesterol: Over 94%
- Resolution of High Blood Pressure: Over 67%
- Resolution of Sleep Apnea: Over 80%
Preparation for Surgery
Prior to the day of surgery, you will have blood drawn for pre-operative tests as well as an electrocardiogram (ECG or EKG), and a chest x-ray. You will go to the hospital several days before surgery to do the necessary paperwork and to meet the anesthesiologist.
On the day before surgery, you are not to eat anything solid, but can take clear liquids. You should take NOTHING by mouth after midnight on the day before surgery. You will take a shower with antimicrobial soap on the evening before surgery, paying special attention to the navel or umbilicus. Bring no jewelry or other valuables with you to the hospital on the day of surgery.
After Surgery – Things to Remember
In The Hospital
You will stay on the Surgical Floor. The nurses can watch your fluid status, heart and lungs very carefully. On the next day, you will get a special x-ray at which time you will be asked to swallow a special dye. This is to ensure that there are no leaks at the pouch. If this x-ray is normal, you will be started on clear liquids.
IT IS IMPERATIVE THAT YOU HAVE A GOOD ATTITUDE AND GET OUT OF THE BED AND DEEP BREATH!
After discharge, you will remain on water, broth, and gelatin for two weeks. You will attend a lecture to discuss your return to “normal” food. There are four important rules that make this program a success:
- Drink your water. Work up to at least 64oz per day. You may add Crystal Lite or squeezed lemon juice for flavor if desired.
- Exercise. Move your body at least 30 minutes per day. After you have fully recovered, we strongly encourage a supervised exercise and weight training program. Studies have shown that, in addition to aerobic exercise, weight-training speeds weight loss!
- Protein First. Once you resume “solid” food, and forever thereafter, eat the protein portion of your meal first. Eat only when you are hungry.
- NO SNACKING! NO SOFT DRINKS! NO MILK!
After this operation, you will have to re-learn to eat and you can expect to regurgitate or vomit from time to time because you will sometimes eat more than the pouch can hold. You and your body are going to have to learn how much you can eat, what you can eat, and how often you can eat.
Regurgitation is common in the first month or so. You’ve had a major operation on your stomach! Your stomach has been stretched, stapled, sewed, and cut. This causes a great deal of inflammation and you must treat your stomach gently at first, avoiding foods that might upset it.
A common concern from patients has been the perception that they can eat a certain amount on one day, but only half that amount the next. For example, let’s say that you ate five bites of hamburger on Friday night, but on Saturday night, you threw up after on two or three bites. What happened? The food from Friday night and Saturday morning was still in your stomach. The opening out of the pouch is very small and designed that way on purpose. This is to prevent your pouch from emptying an ingested meal right away leaving you hungry soon after you eat. Different foods are going to empty from your pouch at different rates and the same foods affect different people differently. This is unpredictable and part of your learning process.
Risks of Gastric Bypass Surgery
- Bleeding: Bleeding is a risk of any operation, especially one in which several incisions are made. The typical amount of blood lost from this operation, however, is minimal. No one leaves the operating room actively bleeding and we routinely draw blood counts every six hours after a gastric bypass within the first 24 hours to determine whether any postoperative bleeding is occurring. Risk: 0.4%
- Infection: Infection rates with abdominal surgery are always higher when one opens the intestine as we do with a gastric bypass. We ask you to clean out the intestines prior to surgery and we administer intravenous antibiotics beginning before the operation and continuing during the hospitalization. We leave a drain in the area of the pouch to remove contaminated fluids before they can become an abscess. Risk 0.7%
- Staple Line Leak: A staple line leak is a complication that generates bad press surrounding a gastric bypass procedure. Staples do not fail, but occasionally the patient’s tissue fails because of poor visceral protein stores and poor collagen formation. To avoid this, we reinforce some of these staples with non-absorbable suture material, test the staple lines and inspect the inside of the pouch while still in the operating room. No one leaves the operating room unless the anastomosis and staple lines are intact. The following morning the patient will swallow some x-ray dye. On rare occasions, some people leak after discharge from the hospital. In this case, we repeat x-ray studies and slowly withdraw the drain over a period of weeks allowing the leak to heal behind the drain as it is withdrawn. Risk: 0.35%
- Stenosis: Anastomotic stenosis is the most common complication after a gastric bypass procedure performed occurring in approximately 4.8% of the patients. If this occurs, it will become gradually symptomatic between three and six weeks after surgery, hallmarked by a decreasing tolerance for different foods and liquids rather than an improved tolerance for different foods and liquids. If this occurs, an appointment with our endoscopist is arranged and an outpatient upper endoscopy is performed with dilatation. If dilatation is performed, a repeat endoscopy is performed in 10-14 days after the initial endoscopy for repeat examination and repeat dilatation. Risk: 5%
- Small Bowel Obstruction: Small bowel obstruction, either from scar tissue or internal hernia can occur after any operation. We anchor the bowel where we wish it to stay and close any gaps with non-absorbable suture material. Risk: 2.0%
- Nutritional Deficiencies: Nutritional deficiencies, particularly with thiamine and other B vitamins, as well as, vitamin D, calcium, iron, and B12 can occur if multivitamins and other supplements are not taken as directed. In addition, essential fatty acids are many times required. We will give our patients a nutritional surveillance handbook after their one month visit. We draw routine blood tests periodically to determine whether the different levels of vitamins are appropriate. In addition, we perform a bone densitometry at 6 and 12 months after surgery. Risk: Patient Dependent
Less Common Risks of Gastric Bypass
- Deep Vein Thrombosis And Pulmonary Embolus
- Aspirations and ARDS
- Lung Abscess
- Plueral Effusion
- Myocardial Infarction – Heart Attack
- Rhabdomyolysis – Injury of Skeletal Muscles
- Side Effects – Not Complications
- Alopecia – Temporary loss of hair
- Dumping Syndrome – uncomfortable and often avoidable
The risks of this operation are not to be taken lightly and should be taken in the context of the experience of the surgeon. The likelihood of these complications happening as stated above reflects our experience and are in no way intended to reflect a nationwide average or intended to reflect complications at programs staffed by less experienced surgeons. Remember, risk is never zero and this is a fact that must be understood by every person contemplating gastric bypass surgery.
1 Buchwald H, Avidor Y, Braunwald E, et al. Bariatric surgery. A systematic review and meta-analysis. JAMA. 2004;292:1724-1737.