Severe obesity is a chronic condition that is hard to treat with diet and exercise alone. Bariatric surgery is an operation on the stomach and/or intestines that helps patients with extreme obesity to lose weight. This surgery is an option for people who cannot lose weight by other means or who suffer from serious health problems related to obesity. The surgery restricts food intake, which promotes weight loss and reduces the risk of type 2 diabetes. Some surgeries also interrupt how food is digested, preventing some calories and nutrients, such as vitamins, from being absorbed. Recent studies suggest that bariatric surgery may even lower death rates for patients with severe obesity. The best results occur when patients follow surgery with healthy eating patterns and regular exercise.
Bariatric Surgery for adults: Currently, bariatric surgery may be an option for adults with severe obesity. Body mass index (BMI), a measure of height in relation to weight, is used to define levels of obesity. Clinically severe obesity is a BMI ≥ 40 or a BMI ≥ 35 with a serious health problem linked to obesity. Such health problems could be type 2 diabetes, heart disease, or severe sleep apnea (when breathing stops for short periods during sleep).
The Food and Drug Administration (FDA) has approved use of an adjustable gastric band for patients with BMI ≥ 30 who also have at least one condition linked to obesity, such as heart disease or diabetes.
Weight loss surgery
Is surgery worth it?
Having surgery to produce weight loss is a serious decision. Anyone thinking about having this surgery should know what it involves. Answers to the following questions may help patients decide whether weight-loss surgery is right for them.
Conditions informed to the patient
• Unlikely to lose weight or keep it off over the long term using other methods?
• Well informed about the surgery and treatment effects?
• Aware of the risks and benefits of surgery?
• Ready to lose weight and improve his or her health?
• Aware of how life may change after the surgery? (For example, patients need to adjust to side effects, such as the need to chew food well and the loss of ability to eat large meals.)
• Aware of the limits on food choices, and occasional failures?
• Committed to lifelong healthy eating and physical activity, medical follow-up, and the need to take extra vitamins and minerals?
The normal digestive process
Normally, as food moves along the digestive tract, digestive juices and enzymes digest and absorb calories and nutrients. After we chew and swallow our food, it moves down the esophagus to the stomach, where a strong acid continues the digestive process. The stomach can hold about 3 pints of food at one time. When the stomach contents move to the duodenum (the first part of the small intestine), bile and pancreatic juice speed up digestion. Most of the iron and calcium in the food we eat is absorbed there. The other two parts of the nearly 20 feet of small intestine absorb nearly all of the remaining calories and nutrients. The food particles that cannot be digested in the small intestine reside in the large intestine until eliminated.
How does surgery promote weight loss?
Bariatric surgery restricts food intake, which leads to weight loss. Patients who have bariatric surgery must commit to a lifetime of healthy eating and regular exercise. These healthy habits may help patients maintain weight loss after surgery.
The type of surgery that may help an adult or youth depends on a number of factors. Patients should discuss with their health care providers what kind of surgery is suitable for them.
What is the difference between open and laparoscopic surgery?
Bariatric surgery may be performed through “open” approaches, which involve cutting the stomach in the standard manner, or by laparoscopy. With the latter approach, surgeons insert complex instruments through 1/2-inch cuts and guide a small camera that sends images to a monitor. Most bariatric surgery today is laparoscopic because it requires a smaller cut, creates less tissue damage, leads to earlier hospital discharges, and has fewer problems, especially hernias occurring after surgery. However, not all patients are suitable for laparoscopy. Patients who are considered extremely obese, who have had previous stomach surgery, or who have complex medical problems may require the open approach. Complex medical problems may include having severe heart and lung disease or weighing more than 350 pounds.
What are the weight loss surgical options?
There are four types of operations that are commonly offered in the United States: AGB, Roux-en-Y gastric bypass (RYGB), biliopancreatic diversion with a duodenal switch (BPD-DS), and vertical sleeve gastrectomy (VSG). (See Figure 1.) Each surgery has its own benefits and risks. The patient and provider should work together to select the best option by considering the benefits and risks of each type of surgery. Other factors to consider include the patient’s BMI, eating habits, health conditions related to obesity, and previous stomach surgeries.
What are the side effects of these surgeries?
Some side effects may include bleeding, infection, leaks from the site where the intestines are sewn together, diarrhea, and blood clots in the legs that can move to the lungs and heart. Examples of side effects that may occur later include nutrients being poorly absorbed, especially in patients who do not take their prescribed vitamins and minerals. In some cases, if patients do not address this problem promptly, diseases may occur along with permanent damage to the nervous system. These diseases include pellagra (caused by lack of vitamin B3—niacin), beri beri (caused by lack of vitamin B1—thiamine) and kwashiorkor (caused by lack of protein).
Other late problems include strictures (narrowing of the sites where the intestine is joined) and hernias (part of an organ bulging through a weak area of muscle). Two kinds of hernias may occur after a patient has bariatric surgery. An incisional hernia is a weakness that sticks out from the abdominal wall’s connective tissue and may cause a blockage in the bowel. An internal hernia occurs when the small bowel is displaced into pockets in the lining of the abdomen. These pockets occur when the intestines are sewn together. Internal hernias are thought to be more dangerous than incisional ones and need prompt attention to avoid serious problems. Some patients may also require emotional support to help them through the changes in body image and personal relationships that occur after the surgery.