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Dieting; Obesity; Weight loss
Surgical procedures for obesity may be appropriate for some dangerously obese people, and they may reduce heart problems and many of the risks associated with obesity. These risks include high blood pressure, sleep apnea, and diabetes. In fact, some evidence suggests that surgery may provide much greater control of weight and diabetes than nonsurgical weight-loss methods. Studies are reporting significant reductions in diabetes, and the need for diabetic medications, after surgery. Other medical conditions that often improve after surgery include heartburn, arthritis, and other joint and circulation problems.
The care of patients undergoing bariatric surgery, before and after surgery, requires specialized expertise and facilities. Studies have shown that the likelihood of complications is significantly associated with the experience of the surgeon and staff.
Bariatric surgeries produce weight loss through one of two approaches:
The malabsorptive procedures are more successful in achieving weight loss than the banding approach, but they carry a greater risk for nutritional deficiencies.
Most people who have bariatric surgery lose about two-thirds of excess weight within 2 years. In addition, diseases associated with obesity (such as diabetes, high blood pressure, sleep apnea, joint pain, and incontinence) often improve.
A number of studies have been published showing that bariatric surgery leads to improved control of diabetes and hypertension.
Other studies have shown that even though most patients maintain significant weight loss, the majority regain about 10% of their weight. Patients must still develop a healthy lifestyle and be calorie conscious after the operation. Follow-up must be lifelong.
Any surgical candidate must have failed consistently in losing weight through less invasive methods. Experts recommend bariatric surgery only for the following:
Patients with binge eating disorder should be identified before surgery and treated. A full evaluation, including a psychological evaluation, should be performed on all candidates for surgery.
Depending on insurance coverage and which procedure is performed, the cost of bariatric surgery may be up to $35,000
Patient considering bariatric surgery should be well-informed regarding the procedure, its efficacy, side effects, and complications. They should also understand the following:
About a third of people who undergo these procedures achieve normal weight, and 80% experience some weigh loss. They are less successful than the bypass procedures, but carry a lower risk of nutritional deficiencies.
Laparoscopic Gastric Banding. Laparoscopic gastric banding (the Lap-Band) usually does not require a major incision and avoids some of the major complications of gastric bypass. Patients lose almost one third to one half of their excess weight after this procedure. Some smaller trials have shown remission of type 2 diabetes in over 70% of patients having the surgery, compared to around 10% treated medically. Death during or after the surgery occurs in fewer than 1/1000 of these procedures.
The Lap-Band procedure restricts the amount of food a person can eat and gives the feeling of fullness. It employs an adjustable silicone band that is placed around the upper part of the stomach. A small balloon-like reservoir attached to the band under the abdominal skin contains saline, which can be added or removed to tighten or loosen the band.
The band is removable, if necessary. Studies to date indicate that the intestinal tract returns to normal afterward. Studies, including those done in the elderly, have reported significant weight loss and improved quality of life with the procedure.
Malabsorptive procedures produce greater weight loss than restrictive procedures. Patients generally achieve about two-thirds of their weight loss within 2 years. Furthermore, in a 2003 study, after standard bypass surgery, 83% of patients with type 2 diabetes had normal blood glucose levels, and the rest had significant weight reductions.
Roux-en-Y Gastric Bypass Procedure. This is the most common and successful malabsorptive surgery in the United States. It involves creating a small stomach pouch that serves as a reservoir and restricts food intake. The pouch eventually holds up to 3 ounces of food and has a small outlet that delays emptying and causes a feeling of fullness. Then the surgeon creates a Y-shaped section in the small intestine that attaches to the pouch. This section allows food to bypass the lower stomach and upper part of the intestine.
Patients on average lose about 60% of their excess weight. Studies have shown improvements in control of type 2 diabetes and reduction in blood pressure. The procedure produces greater and more sustained weight loss than banding procedures, but it is also more complicated. Laparoscopy techniques, which are less invasive, are now preferred over open surgery. They achieve equally good results with fewer complications. Death during or after the surgery occurs in five out of 1000 patients having this procedure.
By definition, these procedures bypass the first part of the small intestine and carry poorly digested food to a part of the intestine that cannot absorb it as easily. Some patients develop what is called dumping syndrome. Symptoms include nausea, vomiting, bloating, cramping, diarrhea, sweatiness, dizziness, and fatigue. These problems occur anywhere from immediately after eating to 3 hours afterwards. Patients with this problem carry a higher risk of nutritional deficiencies..
General Side Effects and Complications. Side effects and complications of bariatric procedures are common, and up to 25% of patients need corrective or repeat procedures. After any of these procedures people must chew all their food carefully, and they cannot eat large amounts of food at one time. If patients do not follow these guidelines, they will experience nausea, abdominal distress, or both.
Complications from any bariatric procedure include:
People at highest risk for complications are those with heart or lung problems, severe obesity, and a history of abdominal surgeries. The mortality rate from bariatric surgeries is 0.2%, which is lower than the morality rates from severe obesity itself.
Specific Complications of Restrictive Banding Procedures. Nausea, vomiting, or both occurs in half of patients, and severe heartburn occurs in a third. Device-related complications include band slippage, pouch dilation (widening), or both in nearly a quarter of patients, and obstruction in 12% of patients. Very serious complications are rare, but they can include blood clots, bleeding, infection, pneumonia, and perforation (tearing) of the stomach.
Specific Complications of Malabsorptive Bypass Procedures. Vomiting often occurs. Nutritional deficiencies occur more often in these procedures.
Most people stay in the hospital for a few days after gastric bypass surgery. Patients are discharged when they can:
Patients continue to eat a liquid or soft diet for several weeks after the surgery. In patients receiving a pouch procedure, the pouch eventually expands to about one cup of chewed food (a normal stomach can hold up to one quart).
Follow-up appointments are essential to determine if nutritional supplements, such as iron, calcium, vitamin B12, or other nutrients, are needed. Supplements, such as a multivitamin with minerals, may be prescribed.
Patients should eat small meals (usually six) throughout the day, rather than large meals that the stomach can no longer handle.
The new stomach probably won't be able to handle both solid food and fluids at the same time. Patients should separate fluid and food intake by at least 30 minutes and only sip what they are drinking.
After surgery, tolerance of fat, alcohol, or sugar decreases. Patients should reduce their fat intake, especially:
Exercise and the support of others (for example, joining a support group with people who have undergone weight-loss surgery) are extremely important in achieving and maintaining weight loss after bariatric surgery.
Exercising can usually resume 6 weeks after the operation. Even sooner than that, most patients will be able to take short walks at a comfortable pace, after consulting with their doctor.
Liposuction eliminates fat in specific areas, such as the abdomen, thighs, buttocks, or knees. Special instruments are inserted through the skin into the pockets, and suction is used to move the fat, break it up, and remove it. Small tubes may be used to drain blood and fluid during the first few days. The pain after the operation can be severe, and often the skin does not contract, resulting in a flabby look. Complications can include burns from the vibrators, bruising, blood clots, and bleeding. Weight gain generally tends to develop in other locations after the operation.

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