Gastric bypass for obesity (Open)
What is the procedure and how is it performed?
Gastric bypass surgery is one type of procedure that can be used to cause significant weight loss if you are very obese. The surgery reduces your body's intake of calories. Calorie reduction is accomplished in two ways:
1. After the surgery, your stomach is smaller. You feel full faster and learn to reduce the amount that you eat at any given time.
2. Part of your stomach and small intestines are literally bypassed so that fewer calories are absorbed.
Gastric bypass surgery is performed under a general anesthesia. This means you inhale analgesics as a gas or receive them through an intravenous (IV) line so that you're asleep and pain-free during the surgery.
The beginning of the stomach is then stapled off to the size of golf ball. The small intestine (jejunum) is then divided and the distal portion (or Roux limb) is then brought up to the new gastric pouch and joined or anastomosed. This allows the food to bypass the rest of the stomach and beginning of the intestines.
The other end of small intestine is then joined up to the Roux limb further downstream. This allows digestive juices from the stomach and organs to mix with the digested food further down. A tube may be inserted into your excluded portion of stomach and this will be removed in 4-6 weeks as an outpatient if you are doing well. The entire procedure usually takes about 4 hours.
Why is this procedure performed?
This procedure is performed for those morbidly obese patients that have been unable to lose weight through non-operative weight loss methods. There are guidelines proposed by the National Institute of Health (NIH) for gastric bypass. You must have a BMI>40 or >35 with co-morbidities, such as diabetes or hypertension directly related to your obesity. BMI is calculated using your height and weight. It gives clinicians a single objective number to define your obesity.
In the first two years of surgery, you can expect to lose 50 percent to 60 percent of your excess weight. It is one of the safest and most effective surgical methods of weight loss.
What should I expect during the post-operative period?
After the surgery, you will be given intravenous pain medication to keep you comfortable. You will have a urinary catheter placed in the operating room that will come out in several days. You will not eat right away and often feel nauseated from the medications and anesthesia. A swallow study (x-ray) may be ordered prior to resuming a diet to evaluate your new gastric pouch and its connection to the small intestine.
You will be encouraged to ambulate after surgery as soon as possible. This decreases your risk of pulmonary complications and clots in your legs. Bowel movements may not occur for several days after the surgery but the return of bowel function will be noted when you start to pass gas.
You will be unable to lift heavy objects (> 15 pounds) and should avoid strenuous activity for 6 weeks after surgery. The dressing will be removed in the hospital and typically you will be able to shower when the dressing is removed.
You will be unable to drive while you are on painkillers. You will typically spend 4-6 days in the hospital and you will have can resume all your normal activities 3-6 weeks after the procedure.
If you were on medications for any co-morbidities such as diabetes or hypertension, they may be resumed slowly as dosages are modified with your new eating habits.
What are the risks and complications of this procedure?
Just as there may be benefits to the procedure(s) proposed, medical and surgical procedures also involve risks. These risks include allergic reaction, bleeding, blood clots, infections, adverse side effects of drugs, heart attack, stroke, and even loss of bodily function or life, as well as risks of transfusion reactions and the transmission of infectious disease, including hepatitis and Acquired Immune Deficiency Syndrome (AIDS), from the administration of blood and/or blood components.
There are also particular risks associated with the procedure(s) proposed and that these risks include, but are not limited to:
- Risks of general anesthesia: difficulties with breathing and reactions to the anesthetic gases or medications used.
- Wound infection: Symptoms include fevers, undue pain, redness, drainage or swelling at the incision site.
- Urinary tract infection or retention: Any foreign body such as a urinary catheter poses a risk for infection.
- Incisional hernia: Bulging or a mass through the incision may be a sign. Refraining from strenuous activity for 6 weeks after surgery is important for adequate healing of the tissues.
- Blockage of the intestines: Scar tissue or adhesions form after almost every surgical procedure. Adhesions typically begin to form within the first few days after surgery, but they may not produce symptoms for months or even years. As scar tissue begins to restrict motion of the small intestines, passing food through the digestive system becomes progressively more difficult. The bowel may become blocked.
- Gastritis/Ulcers: inflammation of the lining of the stomach.
- Iron or vitamin B12 deficiencies: (if they occur) can lead to anemia.
- Calcium deficiency: (if it occurs) can contribute to the development of early osteoporosis or other bone disorders.
- Dumping syndrome: This occurs when food moves too quickly through the stomach and intestines. It causes nausea, weakness, sweating and faintness after eating.
- Nausea/Vomiting: from eating more than the stomach pouch can hold
- Gallstones: due to significant weight loss in a short amount of time
- Delay in return of bowel function (Ileus): When the abdomen is entered as in a colectomy, the intestines temporarily stop their normal forward movement or peristalsis. Typically, 2-3 days following surgery bowel function will return. When this is delayed, patients may feel bloated and nauseated. Early ambulation after surgery may assist in the return of function.
- Anastomotic leak: Rarely, the connection of the intestines can leak or the connection of the stomach pouch to the small intestine can leak. This can lead to an infection in the abdomen called peritonitis.
- Hemorrhage: Bleeding may occur from the blood vessels or at the anastomosis.
- Injury to spleen: This organ is in close proximity to the left portion of the large intestine. Traction at this area can cause the splenic capsule to tear and lead to bleeding.
- Deep vein thrombosis and pulmonary embolism: Blood clots can form in your legs. These clots can travel to the blood vessels in your lungs and lead to severe respiratory problems and even death.
- Stomal stenosis: The new connection between the new gastric pouch and the small intestine can become narrowed leading to nausea and vomiting after eating.
- Follow-up surgeries: to correct complications or problems such as hanging skin.
Before you agree to any operative procedure it is important to remember that each patient is different and that the outcome of any surgical procedure can never be guaranteed. You should understand that there may be complications that have not been mentioned and that it is not possible to anticipate all complications or to answer each and every question. Again, you should be aware that in the practice of medicine unforeseen and unexpected risks or complications not previously discussed may occur. You should also understand that during the course of the proposed procedure(s), unforeseen conditions may be revealed requiring the performance of additional procedures, and such procedures may need to be performed.
Keep in mind that there is no substitute for an open and honest discussion with your own surgeon/physician regarding this procedure.
You should also be given any available treatment alternatives to this procedure by your doctor. Be sure to discuss any questions or concerns with your doctor.
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