MEDICAL MONDAYS News Notes
Charles Morton, MD, bariatric surgeon
Mitzi Gargus, LapBand Patient
TOPIC: Weight Loss Surgery
Monday, August 2, 2010
A staggering statistic--Tennessee NOW Ranks #2 (tied with Alabama), following Mississippi with the greatest population of obese individuals in the United States.
news notes via www.webmd.com
An Overview of Weight Loss Surgery
Severe obesity is a chronic condition that is very difficult to treat. For some people, weight loss surgery -- or bariatric surgery -- helps by restricting food intake or interrupting digestive processes. But keep in mind that weight loss surgery is a serious undertaking. You should clearly understand the pros and cons associated with the procedures before making a decision.
In order to understand how weight loss works, you need to first understand how the normal digestive process functions.
Normally, as food moves along the digestive tract, appropriate digestive juices and enzymes arrive at the right place and at the right time to 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 three pints of food at one time. When the stomach contents move to the duodenum, the first segment of the small intestine, bile and pancreatic juices speed up digestion. Most of the iron and calcium in the foods we eat is absorbed in the duodenum. 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 (made up of the ascending colon, transverse colon, descending colon, sigmoid colon and rectum) until eliminated.
Obesity surgery involves making changes to the stomach and/or small intestine.
How Does Weight Loss Surgery Work?
The concept of gastric surgery to control obesity grew out of results of operations for cancer or severe ulcers that removed large portions of the stomach or small intestine.
Because patients undergoing these procedures tended to lose weight after surgery, some doctors began to use such operations to treat severe obesity. The first operation that was widely used for severe obesity was a type of intestinal bypass. This operation, first used 40 years ago, caused weight loss through malabsorption (decreased ability to absorb nutrients from food because the intestines were removed or bypassed).
The idea was that patients could eat large amounts of food, which would be poorly digested or passed along too fast for the body to absorb many calories. The problem with this surgery was that it caused a loss of essential nutrients (malnutrition) and its side effects were unpredictable and sometimes fatal. The original form of the intestinal bypass operation is no longer used.
Surgeons now use other techniques that produce weight loss primarily by limiting how much the stomach can hold. Two types of surgical procedures used to promote weight loss are:
Through food intake restriction, malabsorption, or a combination of both, you can lose weight since less food either goes into your stomach or stays in your small intestine long enough to be digested and absorbed.
Benefits and Risks of Weight Loss Surgery
Weight loss surgery is a serious undertaking. Before making a decision, talk to your doctor about the following benefits and risks.
Risks and Side Effects
Am I a Candidate Weight Loss Surgery?
If you have a body mass index (BMI) of 40 or more -- which is about 100 pounds overweight for men and about 80 pounds for women -- you are considered severely obese and therefore a candidate for weight loss surgery.
Obesity surgery may also be an option for people with a BMI between 35 and 40 who suffer from obesity-related problems (for example, severe sleep apnea, obesity-related heart disease, or diabetes). For these people, the risk of death from not having the surgery may be greater than the risks from the possible complications from undergoing the procedures.
Keep in mind that as in other treatments for obesity, results may vary. In many cases, patients are required to show proof that their attempts at dietary weight loss have been ineffective before surgery will be approved. A psychological evaluation may be required by doctors to determine your potential response to weight loss and change in body image. Most surgeons require patients to demonstrate serious motivation and a clear understanding of the extensive dietary, exercise, and medical guidelines that must be followed for the remainder of their lives after having weight loss surgery. In addition, studies are performed to assess the health of your heart and hormonal systems. Nutritional counseling is also a must before and after surgery.
For patients who remain severely obese after non-surgical approaches to weight loss have failed, or for patients who have an obesity-related disease, surgery may be an appropriate treatment option. But for most patients, greater efforts toward weight control, such as changes in eating habits, lifestyle changes, and increasing physical activity, are more appropriate. The following questions may help you decide if weight loss surgery is right for you.
What Happens During Weight Loss Surgery?
The term "bariatric" refers to the treatment of obesity. Bariatric surgery -- also called weight loss surgery -- has been practiced in one form or another since the 1950s, but for decades it remained a relatively uncommon weight loss treatment in the United States.
Recently, however, the number of people having bariatric surgery has spiked. In 1998, about 13,000 weight loss surgeries were done in the U.S. Just five years later, about 121,000 were done. The American Society for Metabolic and Bariatric Surgery says an estimated 205,000 people with severe obesity had weight loss surgery in 2007.
This figure may be nowhere near the peak. Only 1% of obese people in the U.S. who could potentially benefit from weight loss surgery have had it.
As more people are having weight loss surgery than ever before, medical researchers have also begun to report solidly favorable study results on its safety and weight loss potential.
People who have bariatric surgery can have dramatic weight loss. What's more, they can maintain much of their initial weight loss for as long as ten years after surgery.
Bariatric surgery works in three basic ways:
Restrictive Weight Loss Surgery: Gastric Banding and Gastroplasty
The two purely restrictive types of weight loss surgery done today are called gastric banding and gastroplasty. Both operations make less room in the stomach for food right after it's swallowed.
A small part of your stomach is partitioned off to make a pouch at the end of your esophagus (the tube connecting your mouth to your stomach). This pouch holds only about one-half ounce -- roughly the capacity of a shot glass. It fills up quickly and empties slowly, through a narrow opening to the larger part of the stomach.
Gastric banding involves placing a band around the top end of the stomach. There are two approved gastric banding devices and procedures approved in the U.S. -- LAP-BAND and the Realize band.
Gastroplasty is what people sometimes call "stomach stapling." It creates a small pouch by sealing off a section of the stomach with surgical staples in addition to placing a band around the opening between the pouch and the rest of the stomach, similar to the gastric banding method.
Malabsorptive Weight Loss Surgery: Gastric Bypass and Billiopancreatic Bypass
Gastric bypass surgery also involves stapling the stomach to create a small pouch. The difference between gastric bypass and gastric banding is that food doesn't pass through the pouch to be further digested in the larger part of the stomach.
Instead, the pouch empties directly into the small intestine. To make this work, the small intestine is severed. The surgeon connects one end of it to an opening in the new stomach pouch. The piece of intestine that's still connected to the stomach's natural opening is what's called the duodenum. In the duodenum, juices from the pancreas flow in to mix with food and help to further digest food leaving the stomach.
In a typical gastric bypass, the surgeon rejoins the duodenum with the intestinal tract about 20 to 40 inches down from the new stomach opening. This way, pancreatic juices can empty into the intestine, but they don't mix with food as soon as they normally would. Few purely malabsorptive operations are done in bariatric surgery today.
The one up-to-date technique labeled as malabsorptive is called a "billiopancreatic bypass with duodenal switch." This operation is similar to a gastric bypass, but has some major differences. First, it involves completely removing much of the stomach, not just sealing off part of it. Second, pancreatic juices enter near the end of the small intestine, close to the colon (large intestine).
How Does Weight Loss Surgery Work?
Bariatric surgery causes weight loss mainly by forcing you to eat less. After surgery, you simply can't consume enough calories to keep your weight up. With a tiny stomach pouch, overeating is physically impossible, or at least extremely uncomfortable. Also, what little you do eat gives a long-lasting feeling of fullness, so you tend to eat less frequently.
Malabsorption may discourage you from eating greasy or sugary food. Bypassing part of the small intestine prevents some fat from being digested, causing severe diarrhea. Eating food with high sugar content can cause an attack of nausea, gut pain, and diarrhea known as "dumping syndrome." People who've had bariatric surgery learn to change their diet to avoid these side effects. Doing so rules out many foods that are also high in calories.
Scientists have also recently discovered that bariatric surgery may cause hormonal changes and effects on the nervous system that suppress appetite, too. Much about how these changes relate to weight loss is still unknown.
Deciding on Weight Loss Surgery
Before you have weight loss surgery, you'll go through an evaluation process that includes counseling and various tests. It's not an operation that anyone gets on a whim. "It's something that most people have been thinking about for years," says Kelvin Higa, MD, president of the American Society for Metabolic and Bariatric Surgery.
One-on-one counseling that takes all your individual needs and preferences into account can help you choose the best type of bariatric surgery for you. "One size does not fit all," Higa tells WebMD.
Your doctor may strongly prefer a certain operation, but at least for now there isn't a generally accepted "gold standard" in weight loss surgery, Higa says.
Gastric bypass, gastric banding, gastroplasty, and biliopancreatic bypass all have pros and cons. Those that involve more cutting, sewing, and rearranging things inside of you may yield slightly better results, but they also may come with more side effects.
The basic requirements for weight loss surgery are:
In general, doctors want to operate on people who've been unable to achieve lasting weight loss with lifestyle changes alone. Some doctors, but not all, even require patients to lose some weight before having surgery.
"They ought to try diet and exercise first," says Walter Pories, MD, a bariatric surgeon at East Carolina University's Brody School of Medicine. But when that's not enough, "surgery can be extremely effective."
After Weight Loss Surgery
All weight loss surgery, whether open or laparoscopic, is done under general anesthesia and involves a short hospital stay. Laparoscopy is a technique used to operate without cutting open the abdomen to get at the organs. Laparoscopy leaves smaller scars than open surgery and tends to have fewer complications and quicker recovery time. Ninety percent of gastric bypasses are done this way.
Fortunately, there is very little risk of dying during bariatric surgery, with rates near or well below 1%. Serious complications after surgery are possible, but rare. To have the best chance of avoiding complications, it's important to go to all your follow-up visits and stick to your prescribed diet and lifestyle plan.
Immediately after surgery, your digestive system will be very tender. "It's like being a baby," Higa says. "You don't feed a baby prime rib."
For the first day or two after bariatric surgery, you will only have a tiny amount of clear liquids such as water, fruit juice, and broth. After that you may start to sip denser liquids like milk, smooth cooked cereal, and pudding. For the next three to four weeks, you'll eat several tiny portions each day of pureed food and liquids. In the second month, you may begin to eat soft, moist, chewed food, including ground meat. Three months after bariatric surgery, you may be back to a regular diet. Nevertheless, you'll never be able to eat big portions again.
Weight loss after bariatric surgery can be dramatic and immediate. After gastric bypass surgery, for example, people lose as much as a pound a day for the first three months.
Weight loss surgery can also improve or cure some health conditions related to obesity. For example, a review published in The Journal of the American Medical Association in 2004 found that diabetes went away completely in 77% of diabetes patients after weight loss surgery, and 86% had some improvement in their diabetes.