1. What is "bariatrics"?
2. What is obesity and what causes it?
3. What happens during digestion?
4. What weight-loss programs are available at Emory?
5. What are some of the medical (non-surgical) options for weight loss at Emory?
6. Who is a candidate for weight loss surgery?
7. How does surgery promote weight loss?
8. What are some restrictive operations for weight loss?
9. What is a gastric bypass operation?
10. What are the benefits of surgery?
11. What are the risks of surgery?
12. Is surgery right for me?

1. What is "bariatrics?"

The study, diagnosis and treatment of obesity and its causes.

Obesity is generally defined as the condition of having a BMI greater than or equal to 30, which can be determined with a BMI calculator. Forty million Americans are obese, and 30% of men and 40% of women between the ages of 40 and 49 are at least 20% over their ideal weight. Obesity increases as people age.

Obesity increases the risk of such major illnesses as stroke; heart disease; diabetes; some types of cancer, such as colon, breast, and uterine cancer; and osteoarthritis (the stiff, sore joints that some people acquire as they age). Obesity also makes it more difficult for health care providers to provide adequate physical exams and causes surgery and any type of body scanning, such as x-rays, to be more problematic.

Normally, as food moves through the digestive tract, digestive juices and enzymes digest and absorb calories and nutrients. After food is chewed and swallowed, it travels down the esophagus to the stomach (which can hold approximately three pints of food at one time) to be broken down by a strong acid. The resulting material moves to the first segment of the small intestine known as the duodenum, whereupon most of the iron and calcium is absorbed and bile and pancreatic juice begin accelerating the digestive process. The jejunum and ileum, the remaining two segments of the nearly 20 feet of small intestine, complete the absorption of almost all calories and nutrients. The food particles that cannot be digested in the small intestine are stored in the large intestine until eliminated.

The Emory Bariatric Center in Atlanta, GA, offers a multi-disciplinary strategy to combat obesity utilizing physicians, psychologists, dietitians, exercise specialists, medical services and, when appropriate, surgical interventions.

Once the patient is enrolled in the medical services program, the center's team will evaluate the patient's current diet, work on establishing a healthy diet, educate the patient about lifestyle changes and assist in customizing a plan that best suits the patient's needs. The center offers both one-on-one treatment and the Comprehensive Weight Management Program, which uses a liquid meal replacement to help achieve safe, rapid weight loss while providing lifestyle education for long-term weight management.

Candidates for surgery usually have a body mass index (BMI) above 40, which translates into 100 pounds or more overweight for men and about 80 pounds for women. Surgery may also be an option for people with a BMI between 35 and 40 who suffer from chronic or life-threatening complications of their obesity such as severe sleep apnea or obesity-related heart disease or diabetes.

Upon observing the results of operations for cancer or severe ulcers that removed large portions of the stomach or small intestine, the concept of stomach surgery to control severe obesity developed. Patients that had these procedures tended to lose weight, influencing some physicians to apply the operations to treating severe obesity. Intestinal bypass, initially performed 40 years ago, was the first such widely-used operation. Producing weight loss by causing caloric malabsorption, it was assumed that while the procedure would allow patients to eat as much as they wanted, it would also cause poor digestion or accelerate the digestive process too quickly for the body to absorb many calories. Unfortunately, the surgery actually instigated a notable loss of essential nutrients while also having unpredictable and occasionally fatal side effects. The original form of this operation is no longer used.

Surgeons now apply laparoscopic techniques that produce weight loss primarily by limiting how much food the stomach can hold. These restrictive procedures are often combined with minimally invasive bypass methods that partially limit calorie and nutrient absorption and may lead to altered food choices.

Two ways that surgical procedures promote weight loss are:

• By decreasing food intake (restriction): Gastric banding, gastric bypass and sleeve gastrectomy limit the amount of food the stomach can hold by closing off or removing parts of the stomach. These operations also delay emptying of the stomach.
  
  
• By causing food to be poorly digested and absorbed (malabsorption): In gastric bypass procedures, surgeons make a direct connection from the stomach to a lower segment of the small intestine, bypassing the duodenum and a potion of the jejunum.

Restrictive operations for obesity include stomach banding and sleeve gastrectomy. Both operations serve only to restrict food intake and do not interfere with the normal digestive process.

• Gastric banding: A band made of special material is placed around the stomach near the upper end, creating a small pouch and a narrow passage into the larger remainder of the stomach.
  
  
• Sleeve gastrectomy: This procedure involves the laparoscopic removal of approximately 75 percent of the stomach, leaving the remainder shaped like a long tube or sleeve. Food intake is restricted without intestinal bypass or malabsorption.

After these operations, a common side effect is vomiting caused by the small stomach being overly stretched by food particles that have not been sufficiently chewed. In addition to being certain to adequately chew their food, patients should eat only half to a whole cup of food per meal to avoid discomfort or nausea. Post procedure, most patients are unable to eat large amounts of food at one sitting, though it is possible for some to eat modest amounts of food without feeling hungry afterwards. While restrictive operations lead to weight loss in almost all patients, weight regain can occur. In all weight-loss procedures, successful results depend on the patient's motivation and behaviors.

9. What is a gastric bypass operation?

Gastric bypass operations performed by the center's surgical staff combine the restriction of food intake with construction of bypasses of the duodenum and other segments of the small intestine to cause reduced calorie and nutrient absorption, known as malabsorption. Since these procedures don't just decrease food intake, they produce more weight loss than restrictive operations. Patients who have bypass operations generally lose two-thirds of their excess weight within two years.

Roux-en-Y gastric bypass (RGB), the most common gastric bypass procedure, restricts food intake by creating a small stomach pouch with stapling, after which a Y-shaped section of the small intestine is attached to the pouch that allows food to bypass the stomach and the first segment of the small intestine (the duodenum and the jejunum), producing malabsorption.

Possible side effects of gastric bypass include pouch stretching, band erosion, breakdown of staple lines, leakage of stomach contents into the abdomen and nutritional deficiencies caused by food skipping the duodenum, where most iron and calcium is absorbed. Malabsorption of vitamin B12 and iron may result in anemia and the decreased absorption of calcium can contribute to osteoporosis and metabolic bone disease. Nutritional supplements usually prevent these deficiencies.

Gastric bypass operations may also cause "dumping syndrome," a situation where food or liquids travel too rapidly through the small intestine. Sweets are often the culprit. Dumping symptoms, which occur after eating and can include nausea, weakness, sweating, faintness and sometimes diarrhea, usually dissipate after the patient rests.

The more extensive the bypass operation, the greater the possibility for complications and nutritional deficiencies. Patients who have these procedures require close monitoring and life-long use of special foods and such medications as vitamin supplements.

Immediately following surgery, most patients lose weight rapidly and continue to do so for 18 to 24 months. While many regain some of their lost weight after this period, few patients regain it all.

Surgery improves most obesity-related medical conditions. For example, one recent study showed that the blood sugar levels of most diabetic patients returned to normal after weight-loss surgery. Nearly all of those whose blood sugar levels did not normalize were older or had been diabetic for some time, suggesting that early intervention for obesity can eliminate obesity-related diabetes.

11. What are the risks of surgery?

Ten to 20 percent of patients who have weight-loss operations require follow-up procedures to correct complications. Abdominal hernias are the most common complication requiring surgery while less frequent complications include breakdown of the staple line and stretched stomach outlet. Laparoscopic surgery may decrease the incidence of hernias, though such operations should ONLY be performed by surgeons with advanced skills.

During rapid or substantial weight loss, the risk of developing gallstones increases. One-third of such cases typically require a second operation to remove them.

Nearly 30 percent of patients who have weight-loss surgery develop nutritional deficiencies such as anemia, osteoporosis and metabolic bone disease, though these conditions can be avoided with vitamin and mineral supplements.

Since rapid weight loss and nutritional deficiencies can harm a developing fetus, women of childbearing age should avoid pregnancy after surgery until their weight stabilizes.

Surgery may be appropriate for those patients who remain severely obese after non-surgical weight-loss attempts or who have an obesity-related disease. Greater efforts toward weight control, such as changes in eating habits, behavior modifications, and increasing physical activity, may be more suitable for others. Answering the following questions can assist in deciding whether or not the surgical option is for you:

Are you:

• Unlikely to lose weight successfully with (further) non-surgical measures?
• Well informed about the surgical procedure and the effects of treatment?
• Determined to lose weight and improve your health?
• Aware of how your life may change after the operation?
• Willing to make long-term adjustments like chewing thoroughly and eating smaller meals?
• Aware of the potential for serious complications, the associated dietary restrictions and the occasional failures?
• Committed to lifelong medical follow-up?

Do you:

• Have a BMI of 40 or more?
• Have an obesity-related physical problem such as body size that interferes with employment, mobility or family function?
• Have high-risk obesity-related health problems such as severe sleep apnea, obesity-related heart disease or diabetes?
• Have good emotional and psychological support from family and/or friends?

There are no guarantees that surgical or non-surgical methods will produce and maintain weight loss. Success is possible only with the patient's complete and lifelong cooperation and commitment to behavioral change and medical follow-up.