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Related to Obesity Surgery: Weight loss surgery
Obesity surgery is an operation that reduces or bypasses the stomach or small intestine so that severely overweight people can achieve significant and permanent weight loss.
Obesity surgery, also called bariatric surgery, is performed only on severely overweight people who are more than twice their ideal weight. This level of obesity often is referred to as morbid obesity since it can result in many serious, and potentially deadly, health problems, including hypertension, Type II diabetes mellitus (non-insulin dependent diabetes), increased risk for coronary disease, increased unexplained heart attack, hyperlipidemia, and a higher prevalence of colon, prostate, endometrial, and, possibly, breast cancer. In 2003, researchers concluded that obesity surgery could cure Type II diabetes in many people who were not yet morbidly obese. Therefore, this surgery is performed on people whose risk of complications of surgery is outweighed by the need to lose weight to prevent health complications, and for whom supervised weight loss and exercise programs have repeatedly failed. Obesity surgery, however, does not make people thin. Most people lose about 60% of their excess weight through this treatment. Changes in diet and exercise still are required to maintain a normal weight.
The theory behind obesity surgery is that if the volume the stomach holds is reduced and the entrance into the intestine is made smaller to slow stomach emptying, or part of the small intestine is bypassed or shortened, people will not be able to consume and/or absorb as many calories. With obesity surgery the volume of food the stomach can hold is reduced from about four cups to about 1/2 cup.
Insurers may consider obesity surgery elective surgery and not cover it under their policies. Documentation of the necessity for surgery and approval from the insurer should be sought before this operation is performed.
Obesity surgery should not be performed on people who are less than twice their ideal weight. It also is not appropriate for people who have substance addictions or who have psychological disorders. Other considerations in choosing candidates for obesity surgery include the general health of the person and his or her willingness to comply with follow-up treatment.
Obesity surgery is usually performed in a hospital by a surgeon who has experience with obesity surgery or at a center that specializes in the procedure. General anesthesia is used, and the operation takes 2-3 hours. The hospital stay lasts about a week.
Three procedures are currently used for obesity surgery:
- Gastric bypass surgery. Probably the most common type of obesity surgery, gastric bypass surgery has been performed in the United States for about 25 years. In this procedure, the volume of the stomach is reduced by four rows of stainless steel staples that separate the main body of the stomach from a small, newly created pouch. The pouch is attached at one end to the esophagus. At the other end is a very small opening into the small intestine. Food flows through this pouch, bypassing the main portion of the stomach and emptying slowly into the small intestine where it is absorbed.
- Vertical banding gastroplasty. In this procedure, an artificial pouch is created using staples in a different section of the stomach. Plastic mesh is sutured into part of the pouch to prevent it from dilating. In both surgeries the food enters the small intestine farther along that it would enter if exiting the stomach normally. This reduces the time available for absorption of nutrients. The procedure is normally done laparoscopically, meaning that the surgeon makes one or more small incisions in the abdomen and inserts the necessary tools and instruments through the tiny holes. He or she can view the patient's organs via an inserted camera that displays pictures on a monitor. This method makes for a faster and easier recovery than a large incision.
- Jejunoileal bypass. Now a rarely performed procedure, jejunoileal bypass involves shortening the small intestine. Because of the high occurance of serious complications involving chronic diarrhea and liver disease, it has largely been abandoned for the other, safer procedures
After patients are carefully selected as appropriate for obesity surgery, they receive standard preoperative blood and urine tests and meet with an anesthesiologist to discuss how their health may affect the administration of anesthesia. Pre-surgery counseling is done to help patients anticipate what to expect after the operation.
Immediately after the operation, most patients are restricted to a liquid diet for 2-3 weeks; however, some may remain on it for up to 12 weeks. Patients then move on to a diet of pureed food for about a month, and, after about two months, most can tolerate solid food. High fat food is restricted because it is hard to digest and causes diarrhea. Patients are expected to work on changing their eating and exercise habits to assist in weight loss. Most people eat 3-4 small meals a day once they return to solid food. Eating too quickly or too much after obesity surgery can cause nausea and vomiting as well as intestinal "dumping," a condition in which undigested food is shunted too quickly into the small intestine, causing pain, diarrhea, weakness, and dizziness.
As in any abdominal surgery, there is always a risk of excessive bleeding, infection, and allergic reaction to anesthesia. Specific risks associated with obesity
surgery include leaking or stretching of the pouch and loosening of the gastric staples. Although the average death rate associated with this procedure is less than one percent, the rate varies from center to center, ranging from 0-4%. Long-term failure rates can reach 50%, sometimes making additional surgery necessary. Other complications of obesity surgery include an intolerance to foods high in fats, lactose intolerance, bouts of vomiting, diarrhea, and intestinal discomfort
Studies on the risks of these surgeries continue. A 2003 report showed that gastric bypass surgery risk increases with age, weight and male gender. Patients age 55 and older experienced more complications than did younger patients and male patients had more life-threatening complications than female patients, particularly those who were more severely obese.
Many people lose about 60% of the weight they need to reach their ideal weight through obesity surgery. However, surgery is not a magic weight-loss operation, and success also depends on the patient's willingness to exercise and eat low-calorie foods. A 2003 report showed that super obese patients had a lower success rate with laparoscopic vertical banding gastroplasty than those considered morbidly obese. However, the overall success rate was nearly 77% of patients carrying less than 50% excess weight four years after the procedure.
"Gastric Bypass Surgery Risk Increases with Age, Weight, and Male Gender." Medical Devices and Surgical Technology Week January 19, 2003: 29.
"Laparoscopic Vertical Banding Gastroplasty Safe and Effective for Morbid Obesity." Medical Devices and Surgical Technology Week January 19, 2003: 2.
Sadovsky, Richard. "Obesity Surgery May Cure Diabetes in Nonobese Patients." American Family Physician 56 (February 15, 2003): 866.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.