Surgery

After trying several weight-loss approaches, many people who are morbidly obese are unsuccessful in losing and keeping off the weight and opt for weight-loss surgery.

Bariatric surgery, which involves sealing off most of the stomach to reduce the quantity of food you can consume, currently is the most effective means by which morbidly obese people can lose weight and maintain that weight loss.

To be considered for weight-loss surgery, you must meet at least one of the following qualifications:

• Be more than 100 pounds over your ideal, recommended body weight.
• Have a body mass index (BMI) of 40 or higher (20 to 25 is considered a normal). BMI is a number based on both your height and weight. Surgery may be considered with a BMI as low as 35 if your doctor determines that there's a medical need for weight reduction and surgery appears to be the only way to accomplish the targeted weight loss.

To qualify for surgery, you must complete a medical and psychological pre-evaluation process. You must show that you are committed to adhering to long-term, follow-up care after surgery. Most surgeons require that you demonstrate serious motivation and a clear understanding of the extensive dietary, exercise and medical guidelines that must be followed for the remainder of your life.

The UCSF Bariatric Surgery Center has performed surgical weight loss procedures since 1996. Various procedures involve different risks and advantages. During your initial consultation, your surgeon will discuss in detail the different options available to you, along with their associated risks and advantages.

The most common bariatric surgeries are "restrictive" procedures that reduce the size of the stomach and limit the calories you can consume. Another type of procedure — called a malabsorptive procedure — alters your digestion, causing food to be poorly digested and incompletely absorbed so that it is eliminated in the stool.

Gastric Restrictive Procedures

Roux-en-Y Gastric Bypass

Roux-en-Y gastric bypass is the current "gold standard" procedure for weight-loss surgery, according to the American Society for Bariatric Surgery and the National Institutes of Health. One of the most frequently performed weight-loss procedures in the United States, it involves stapling the stomach to create a small — 15 to 20 cubic centimeter — stomach pouch. The remainder of the stomach is not removed, but is stapled shut and divided from the stomach pouch.

The outlet from this newly formed pouch empties directly into the lower portion of the small intestine, called the jejunum, thus bypassing calorie absorption. This is done by dividing the small intestine just beyond the duodenum to connect it with the newly formed stomach pouch. The other end is connected to the side of the Roux limb of the intestine creating a "Y" shape that gives the technique its name. The length of either segment of the intestine can be increased to produce some degree of malabsorption.

Advantages

• Average weight loss after the Roux-en-Y procedure is generally higher than other restrictive procedures, if you rigorously follow instructions.
• A year after surgery, weight loss averages 77 percent of excess body weight.
• Studies show that after 10 to 14 years, 50 percent to 60 percent of excess body weight loss is maintained by some patients.
• Studies have shown that health conditions — such as back pain, sleep apnea, high blood pressure, diabetes and depression — are improved or resolved after surgery.

Disadvantages

• Because the duodenum is bypassed, poor absorption of iron and calcium can result in the lowering of total body iron, which may result in iron deficiency anemia. This is a particular concern for patients who experience chronic blood loss during excessive menstrual flow or bleeding hemorrhoids. Women, already at risk for osteoporosis that can occur after menopause, should be aware of the potential for more bone calcium loss.
• Bypassing the duodenum has caused metabolic bone disease in some patients, resulting in bone pain, loss of height, humped back and fractures of the ribs and hip. All of the deficiencies mentioned, however, can be managed through proper diet and vitamin supplements.
• Chronic anemia due to Vitamin B12 deficiency may occur. This problem usually can be managed with Vitamin B12 pills or injections.
• A condition known as "dumping syndrome" can occur as the result of rapid emptying of stomach contents into the small intestine. This is sometimes triggered when too much sugar or large amounts of food are consumed. While generally not considered a serious health risk, the results can be unpleasant, including nausea, weakness, sweating, faintness and, on occasion, diarrhea after eating. Some patients are unable to eat any form of sweets after surgery.
• In some cases, the procedure's effectiveness may lessen if the stomach pouch is stretched or if it is initially left larger than 15 to 30 cubic centimeters.
• The bypassed portion of the stomach, duodenum and segments of the small intestine cannot be easily visualized using X-ray or endoscopy if problems such as ulcers, bleeding or cancer occur.

Laparoscopic Adjustable Gastric Band (Lap-band)

In this procedure, an adjustable silicone band is placed around the upper part of the stomach to create a stomach pouch that can hold only small amounts of food. The lower, larger part of the stomach is located below the band. The outlet from the pouch is restricted by the band, which slows the emptying of the food and allows one to feel full sooner. Adjustment of the band is performed in the doctor's office by injecting fluid into a small "port," a device implanted beneath the abdominal skin.

Advantages

• Application of the band is less invasive and doesn't involve stapling or cutting the stomach.
• The band is adjustable, allowing your doctor to control the size of the pouch outlet.
• If the band needs to be removed for any reason, the stomach usually returns to its original form.

Disadvantages

• The procedure is relatively new in the United States and it's effectiveness still is being studied. However, it has been used extensively and with good results in Europe and Australia.
• Insurance companies vary widely in the coverage they provide for this procedure.

Vertical Banded Gastroplasty

Vertical banded gastroplasty (VBG) is a restrictive procedure performed less frequently today. The upper stomach near the esophagus is stapled vertically for about 2-1/2 inches, or 6 centimenters, to create a smaller stomach pouch. The outlet from the pouch is restricted by a band or ring that slows the emptying of the food. As a result, a patient will experience a feeling of fullness sooner.

Advantages

• The main advantage of this restrictive procedure is that a reduced amount of well-chewed food enters and passes through the digestive tract in the normal way. the body is able to fully absorb nutrients, vitamins and calories. Studies show that after 10 years, patients can maintain 50 percent of their targeted excess weight loss.

Disadvantages

• Following surgery, staple-line disruption in the stomach can result in leakage or serious infection, requiring hospitalization with antibiotic treatment and or additional operations.
• Staple-line disruption also may lead to weight gain in the long-term. For this reason, some surgeons divide the staple-line wall of the pouch from the rest of the stomach to reduce the risk of staple-line disruption.
• The band or ring applied to the stomach pouch may lead to obstruction or perforation, requiring surgical intervention.
• Typically, these procedures create a sense of fullness, but often not the satisfying feeling of having had "enough" to eat.
• Because restrictive procedures rely on a small pouch to reduce food intake, there is a risk of the pouch stretching or the restricting band or ring breaking or migrating, allowing patients to eat too much.
• About 40 percent of patients undergoing these procedures have lost less than half of their excess body weight.
• All weight-loss surgeries may require readmission to a hospital for fluid replacement or nutritional support if a patient experiences excessive vomiting and cannot maintain adequate amounts of food.

Malabsorptive Procedures

Like gastric restrictive procedures, malabsorptive procedures reduce the size of the stomach, although the stomach pouch is larger. The goal is to restrict the food consumed and alter the normal digestive process. The anatomy of the small intestine is altered so that food is delayed in mixing with bile and pancreatic juices, which aid in the absorption of nutrients. The result is an early sense of fullness, combined with a sense of satisfaction that reduces the desire to eat.

Sleeve Gastrectomy

This procedure involves removing the outer margin of the stomach to restrict food intake, leaving a sleeve of stomach with the pylorus, the muscle that controls emptying of food from the stomach into the intestine. When a sleeve gastrectomy is performed alone, this procedure functions as a purely restrictive procedure.

Biliopancreatic Diversion with Duodenal Switch
Currently, this two-step procedure is not performed at UCSF Medical Center.

This involves performing a sleeve gastrectomy as the first step of the procedure, sometimes performed separately to allow initial weight loss before completing the procedure. After the sleeve gastrectomy is performed, the duodenum, which is the first portion of the small intestine, is divided so pancreatic and bile drainage is bypassed.

The near-end of the "alimentary limb" is then attached to the beginning of the duodenum, just past the pyloris, while the bile and pancreatic juices move through the long "biliopancreatic limb." A "common limb" is created by connecting the "alimentary" and "biliopancreatic" limbs a short distance from the end of the small bowel. Food mixes with the digestive juices in this portion of the intestine and is absorbed.

The length of the common limb may vary to regulate the absorption of carbohydrates, protein, fat and other nutrients.

Extended (Distal) Roux-en-Y Gastric Bypass (RYGBP-E)

RYGBP-E is an alternative to achieve malabsorption by creating a stapled or divided small gastric pouch, leaving the remainder of stomach in place. A long limb of the small intestine is attached to the stomach to divert the bile and pancreatic juices. This procedure carries with it fewer operative risks by avoiding removal of the lower three-quarters of the stomach. Gastric pouch size and the length of the bypassed intestine determine the risks for ulcers, malnutrition and other side effects.

Advantages

• Patients can eat larger meals than with a purely restrictive or standard Roux-en-Y gastric bypass procedure.

• These procedures can produce the greatest excess weight loss because they provide the highest levels of malabsorption.

• In one study of 125 patients, the loss of excess weight averaged 74 percent the first year, 78 percent after two years, 81 percent after three years, 84 percent after four years and 91 percent after five years.

• Long-term maintenance of weight loss can be successful with a straightforward dietary, supplement, exercise and behavioral regimen.

Disadvantages

• Weight-loss surgeries may require hospitalization for fluid replacement or nutritional support if a patient experiences excessive vomiting and cannot maintain adequate amounts of food.

• For all malabsorption procedures, there is a period of intestinal adaptation when bowel movements can be very liquid and frequent. This condition may lessen over time, but may be a permanent lifelong occurrence.

• Abdominal bloating and malodorous stool or gas may occur.

• Close monitoring for protein malnutrition, anemia and bone disease is recommended. Lifelong vitamin supplements are required. If patients don't follow eating and vitamin instructions, at least 25 percent of patients will develop problems that require treatment.

• Changes to the intestinal structure can result in increased risk of gallstone formation and the need to remove the gallbladder.

• Re-routing of bile and pancreatic and other digestive juices beyond the stomach can cause intestinal irritation and ulcers.

Laparoscopic or Minimally Invasive Surgery

Laparoscopic, or minimally invasive, procedures have been used for weight loss surgery for several years. During a laparoscopic operation, a small video camera is inserted into the abdomen. The surgeon views the procedure on a separate video monitor, allowing for better visualization and access. The camera and surgical instruments are inserted through small incisions made in the abdominal wall. Not all surgeons offer laparoscopic weight loss surgery because they aren't properly trained.

The American Society for Bariatric Surgery recommends that laparoscopic weight-loss surgery be performed only by surgeons experienced in both laparoscopic and open bariatric procedures. At the UCSF Bariatric Surgery Center, our experts are trained in the advanced techniques required to perform laparoscopic procedures.

Laparoscopic surgery is considered less invasive because it replaces the need for one long incision to open the abdomen. A recent study showed that patients who underwent laparoscopic weight-loss surgery experienced less pain after surgery, resulting in easier breathing and lung function and higher overall oxygen levels.

Other benefits of laparoscopy are fewer wound complications, such as infection or hernia, and patients returning more quickly to their normal levels of activity.

Not all patients, however, are candidates for this approach.

Experimental 'Incision-Free' Procedure

UCSF Medical Center is one of 10 medical centers testing a new procedure called transoral gastroplasty, known informally as TOGA, which is an "incision-free" procedure.

The surgeon introduces a set of flexible stapling devices through the mouth into the stomach and, with endoscopic imaging, uses the devices to create a restrictive pouch. The pouch is intended to retain food as it enters the stomach, giving patients a feeling of fullness and reducing caloric intake.

More Information

• Bariatric Surgery Information Session
• Bariatric Surgery Support Group

 

Reviewed by health care specialists at UCSF Medical Center.
Last updated February 1, 2012