Obesity
Surgical Treatment for Obesity
Weight-loss surgery (bariatric surgery) is the only option today that effectively treats morbid obesity in people for whom more conservative measures such as diet, exercise, and medication have failed.
There are a variety of approaches to bariatric surgery, but all procedures are either malabsorptive, restrictive, or a combination of the two. Malabsorptive procedures change the way the digestive system works. Restrictive procedures are those that severely reduce the size of the stomach to hold less food, but the digestive functions remain intact.
Gastric Bypass (Malabsorptive) Surgery
(Malabsorptive Procedure, Roux-en-Y Gastric Bypass, Biliopancreatic Diversion)
What is Gastric Bypass Surgery?
Gastric bypass surgery, a type of bariatric surgery (weight loss surgery), is a surgical procedure that alters the process of digestion. Bariatric surgery is the only option today that effectively treats morbid obesity in people for whom more conservative measures such as diet, exercise, and medication have failed.
There are several types of gastric bypass procedures, but all of them involve bypassing part of the small bowel by greater or lesser degrees. For this reason, procedures of this type are referred to as malabsorptive procedures, because they involve bypassing a portion of the small intestine that absorbs nutrients.
Some of these procedures also involve stapling the stomach to create a small pouch that serves as the “new” stomach or surgically removing part of the stomach.
Although a gastric bypass procedure is malabsorptive, it may also be restrictive because the size of the stomach is reduced so that the amount of food that can be eaten is “restricted” due to the smaller stomach. While malabsorptive procedures are more effective in causing excess weight to be lost than procedures that are solely restrictive, they also carry more risk for nutritional deficiencies.
Types of gastric bypass, or malabsorptive, surgical procedures include:
- roux-en-Y gastric bypass (RGB)Roux-en-Y gastric bypass, the most commonly performed bariatric procedure, is both malabsorptive and restrictive. This surgery can result in two-thirds of extra weight loss within two years. The procedure involves stapling the stomach to create a small pouch that holds less food and then shaping a portion of the small intestine into a “Y.” The “Y” portion of intestine is then connected to the stomach pouch so that when food is being digested it travels directly into the lower part of the small intestine, bypassing the first part of the small intestine (called the duodenum) and the first part of the second section of the small intestine (called the jejunum). The effect of bypassing these sections of the intestine is to restrict the amount of calories and nutrients that are absorbed into the body.The Roux-en-Y gastric bypass may be performed with a laparoscope rather than through an open incision in some patients. This procedure uses several small incisions and three or more laparoscopes – small thin tubes with video cameras attached – to visualize the inside of the abdomen during the operation. The surgeon performs the surgery while looking at a TV monitor. Persons with a Body Mass Index (BMI) of 60 or more or those who have already had some type of abdominal surgery are usually not considered for this technique. A laparoscopic method allows the physician to make a series of much smaller incisions. Laparoscopic gastric bypass usually reduces the length of hospital stay, the amount of scarring, and results in quicker recovery than an open procedure.
- biliopancreatic diversion (BPD)A biliopancreatic diversion is both restrictive and malabsorptive, and is a more complicated procedure than the Roux-en-Y procedure. In this procedure a large part of the lower stomach is removed. The small part of stomach that is left is connected directly to the last part of the small intestine (jejunum). As food is digested, it completely bypasses the duodenum and the jejunum. Because this procedure may result in nutritional deficiencies, it is not as commonly performed.A variation of the biliopancreatic diversion is a procedure called the duodenal switch. More of the stomach is retained, including the valve that controls the release of food into the small intestine. This helps to prevent the “dumping syndrome” which can result in vomiting or diarrhea. A small part of the duodenum is also retained.
Digestion is the process by which food and liquid are broken down into smaller parts so that the body can use them to build and nourish cells. Digestion begins in the mouth, where food and liquids are taken in, and is completed in the small intestine. The digestive tract is a series of hollow organs joined in a long, twisting tube from the mouth to the anus.
The stomach is where the three mechanical tasks of storing, mixing, and emptying occur.
Normally, this is what happens:
- First, the stomach stores the swallowed food and liquid, which requires the muscle of the upper part of the stomach to relax and accept large volumes of swallowed material.
- Second, the lower part of the stomach mixes up the food, liquid, and digestive juices produced by the stomach by muscle action.
- Third, the stomach empties the contents into the small intestine.
The food is then digested in the small intestine and dissolved by the juices from the pancreas, liver, and intestine, and the contents of the intestine are mixed and pushed forward to allow further digestion.
Malabsorptive procedures alter this process in different ways depending on the type of procedure.
Reasons for the Procedure
Bariatric surgery is performed because it is currently the best treatment option for producing lasting weight loss in obese patients for whom nonsurgical methods of weight loss have failed.
Potential candidates for bariatric surgery include:
- persons with a Body Mass Index (BMI) greater than 40
- men who are 100 pounds over their ideal body weight or women who are 80 pounds over their ideal body weight
- persons with a BMI between 35 and 40 who have another condition such as obesity-related type 2 diabetes, sleep apnea, or heart disease
Because the surgery can have serious side effects, the long-term health benefits must be considered and found greater than the risk. Despite the fact that some surgical techniques can be done laparoscopically with reduced risk, all bariatric surgery is considered to be major surgery.
Although not all risks with each procedure are fully known, bariatric surgery does help many people to reduce or eliminate some health-related obesity problems. It may help to:
- lower blood sugar
- lower blood pressure
- reduce or eliminate sleep apnea
- decrease the workload of the heart
- lower cholesterol levels
Surgery for weight loss is not a universal remedy, but these procedures can be highly effective in people who are motivated after surgery to follow their physician’s guidelines for nutrition and exercise and to take nutritional supplements.
There may be other reasons for your physician to recommend a gastric bypass procedure.
Risks of the Procedure
As with any surgical procedure, complications may occur. Some possible complications include, but are not limited to, the following:
- infection
- blood clots
- pneumonia
- bleeding ulcer
- development of gallstones
With Roux-en-Y gastric bypass procedures, malabsorptive symptoms may be more serious with an increased risk of anemia and loss of fat-soluble vitamins (vitamins A, D, E, and K). Adequate amounts of iron, calcium, and vitamin B12 may not be absorbed. This can cause metabolic bone disease and osteoporosis.
Stomal stenosis occurs when there is a stricture (tightening) of the opening between the stomach and intestine after a Roux-en-Y procedure. When this occurs, vomiting after eating and sometimes after drinking may occur. Stomal stenosis can be treated easily but should be treated immediately.
“Dumping syndrome” is also more likely to occur with these procedures because the food in the stomach moves to the intestines quickly. Symptoms include nausea, sweating, fainting, weakness, and diarrhea.
There is a risk that additional surgery may be necessary because of complications, including gallstones.
One of the most serious complications of gastric bypass is a stomach leak that can cause peritonitis to develop. Peritonitis is an inflammation of the peritoneum, the smooth membrane that lines the cavity of the abdomen.
There may be other risks depending upon your specific medical condition. Be sure to discuss any concerns with your physician prior to the procedure.
Gastric Stapling (Restrictive) Surgery
(Gastric Banding Surgery, Adjustable Gastric Banding, Vertical Banded Gastroplasty)
What is gastric stapling (restrictive) surgery?
Gastric stapling (restrictive) surgery is a type of bariatric surgery (weight loss surgery) procedure performed to limit the amount of food a person can eat. Bariatric surgery is the only option today that effectively treats morbid obesity in people for whom more conservative measures such as diet, exercise, and medication have failed.
In gastric banding surgery, no part of the stomach is removed and the digestive process remains intact. Either staples or a band are used to separate the stomach into two parts, one of which is a very small pouch that can hold about one ounce of food. The food from this new stomach empties into the closed-off portion of the stomach and then resumes the normal digestive process. Over time, the pouch can expand to hold two to three ounces of food. Because the size of the stomach is reduced so dramatically, this type of procedure is referred to as a restrictive procedure.
After gastric stapling or banding, a person can eat only about three-quarters to one cup of food. The food must be well-chewed. Eating more than the stomach pouch can hold may result in nausea and vomiting. Restrictive procedures pose fewer risks than gastric bypass procedures, but they are also less successful because continuous overeating can stretch the pouch so that it accommodates more food.
The types of gastric banding procedures include:
- adjustable gastric banding (AGB)This procedure involves attaching an inflatable band around the top portion of the stomach and tightening it like a belt to form a small pouch that serves as a new, much smaller stomach. After the procedure, the diameter of the band around the stomach can be adjusted by a physician by adding or removing saline (salt water). No staples are used in this procedure, which is relatively new in the US.Like other restrictive procedures, AGB may not achieve significant weight loss. The US Food and Drug Administration (FDA) approved an AGB system in 2001 that can be put in place with a laparoscope (a small thin tube with a video camera attached) rather than with an open incision for patients who are morbidly obese, as indicated by a Body Mass Index (BMI) of 40 or more.
- vertical banded gastroplasty (VBG)This procedure uses a combination of staples and a band to create the pouch. There is a dime-sized opening at the bottom of the new stomach that opens into the rest of the larger stomach. Plastic tissue or mesh is wrapped around the opening to help prevent the opening from stretching. Weight loss is about 45 percent of extra body weight at one year after the surgery.
- vertical sleeve gastrectomy (VSG)This procedure uses staples to remove a large portion of the stomach; the remaining stomach “sleeve” will hold approximately one-quarter cup of liquid. Over time, the stomach can expand to hold one cup of food.This procedure was created as a first step of a two-step surgery (second step surgery involves changing direction of food in the small intestine for a malabsorption). Many patients lose the desired amount of weight and do not have the second surgery. Weight loss can be 33 percent to 80 percent of excess body weight at one year after surgery. Since the rest of the stomach has been removed, this procedure is not reversible.
VBG and AGB may be performed with a laparoscope rather than through an open incision in some patients. This procedure uses several small incisions and three or more laparoscopes – small thin tubes with video cameras attached – to visualize the inside of the abdomen during the operation. The physician performs the surgery while looking at a TV monitor. Laparoscopic gastric surgery usually reduces the length of hospital stay and the amount of scarring, and often results in quicker recovery than an open or standard procedure.
Persons with a BMI of 60 or more or persons who have already had some type of abdominal surgery are usually not considered as a candidate for the laparoscopic technique.
Digestion is the process by which food and liquid are broken down into smaller parts so that the body can use them to build and nourish cells. Digestion begins in the mouth, where food and liquids are taken in, and is completed in the small intestine. The digestive tract is a series of hollow organs joined in a long, twisting tube from the mouth to the anus.
The stomach is where the three mechanical tasks of storing, mixing, and emptying occur. Normally, this is what happens:
- First, the stomach stores the swallowed food and liquid, which requires the muscle of the upper part of the stomach to relax and accept large volumes of swallowed material.
- Second, the lower part of the stomach mixes up the food, liquid, and digestive juices produced by the stomach by muscle action.
- Third, the stomach empties the contents into the small intestine.
The food is then digested in the small intestine and dissolved by the juices from the pancreas, liver, and intestine, and the contents of the intestine are mixed and pushed forward to allow further digestion.
Reasons for the Procedure
Bariatric surgery is performed because it is currently the best treatment option for producing lasting weight loss in obese patients for whom nonsurgical methods of weight loss have failed.
Potential candidates for bariatric surgery include:
- persons with a Body Mass Index (BMI) greater than 40
- men who are 100 pounds over their ideal body weight or women who are 80 pounds over their ideal body weight
- persons with a BMI of 35 or more who have another condition such as obesity-related type 2 diabetes, sleep apnea, or heart disease
Because the surgery can have serious side effects, the long-term health benefits must be considered and found greater than the risk. Despite the fact that some surgical techniques can be done laparoscopically with reduced risk, all bariatric surgery is considered to be major surgery.
Although not all risks with each procedure are fully known, bariatric surgery does help many people to reduce or eliminate some health-related obesity problems. It may help to:
- lower blood sugar
- lower blood pressure
- reduce or eliminate sleep apnea
- decrease the workload of the heart
- lower cholesterol levels
Surgery for weight loss is not a universal remedy, but these procedures can be highly effective in people who are motivated after surgery to follow their physician’s guidelines for nutrition and exercise and to take nutritional supplements.
There may be other reasons for your physician to recommend a gastric banding procedure.
Risks of the procedure:
As with any surgical procedure, complications may occur. Some possible complications include, but are not limited to, the following:
- infection
- blood clots
- pneumonia
- bleeding ulcer
- development of gallstones
- obstruction or nausea can occur when food is not well-chewed
- poor nutrition
- scarring inside the abdomen
- vomiting due to eating more than the stomach pouch can hold
Risks specific to vertical gastric banding include breakdown of the line of staples and erosion of the band. Rarely, stomach juices may leak into the abdomen and emergency surgery may be needed. The most common complication that may develop with adjustable gastric band surgery is that the stomach pouch enlarges. Band slippage and saline leaks are also risks specific to adjustable gastric band surgery.
Risk is reduced with a laparoscopic banding procedure because there is no incision in the stomach wall.
There may be other risks depending upon your specific medical condition. Be sure to discuss any concerns with your physician prior to the procedure.