Bariatric Surgery includes numerous surgical procedures that are done in obese patients to aid weight loss.
Surgery on the stomach and/or intestines to help the patient with extreme obesity lose weight. These surgical procedures are performed specifically for the purpose of inducing appetite control, weight loss, and long-term dietary modification in the patient.
Bariatric surgery is a weight-loss method used for people who have a body mass index (BMI) above 40. Surgery may also be an option for people with a BMI between 35 and 40 who have health problems like heart disease or type 2 diabetes.
Etymology is Greek Baros = weight, iatros = physician.
Why Surgery is appropriate for Morbid Obesity
Morbid obesity (a term also synonymous with “clinically severe obesity”) is a disease in which the body stores excess energy in the form of fat. Morbid obesity correlates with a Body Mass Index (BMI) of 40 kg/m2 (abbreviated as 40) or with being roughly 100 pounds overweight.
Description of 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 oesophagus 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 segment of the small intestine - bile (from the liver) and pancreatic juice 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.
Those food particles that cannot be digested in the small intestine are stored in the large intestine until eliminated
Bariatric Surgery Goals for Weight Loss Treatment
Surgical treatment is medically necessary because it is the only proven method of achieving long term weight control for the morbidly obese.
Surgical treatment is not a cosmetic procedure. Surgical treatment of severe obesity does not involve the removal of adipose tissue (fat) by suction or excision. Bariatric surgery involves reducing the size of the gastric reservoir, with or without a degree of associated malabsorption. Eating behavior improves dramatically. This reduces caloric intake and ensures that the patient practices behavior modification by eating small amounts slowly, and chews each mouthful well.
The success of surgical treatment must begin with realistic goals and progress through the best possible use of well designed and tested operations. These have been worked out over the last thirty years, and are now standardised, clearly defined procedures, with well recognised and documented outcome results.
The prevention of secondary complications of morbid obesity is an important goal of management. Therefore, the option of surgical treatment is a rational one supported by the time honored principle that diseases which harm call for therapeutic intervention that, while vigorous, is less harmful than the disease being treated.
The biological basis for morbid obesity is unknown, though recent work has demonstrated a genetic component of between 25 and 50%. Several studies confirm the influence of genetically determined proteins produced by the fat cell to be among the many mechanisms which have a place in the control of satiety. These studies confirm that morbid obesity is a disease, not a disorder of will power, as sometimes implied.
The physiologic, biochemical and genetic evidence is overwhelming that morbid obesity is a complex disorder. Contributing causes include inheritance and environmental, cultural, socioeconomic and psychological factors
Considering Non-Operative Weight Loss Treatment
Published scientific reports document that non-operative methods alone have not been effective in achieving a medically significant long term weight loss in severely obese adults. It has been shown that the majority of patients regain all the weight lost over the next five years. The average medical weight reduction trial is a 10-12 week study with average weight loss of 2.5 kg.
The use of anorectic medications has recently been advocated as a long term therapeutic modality in management of what is clearly a chronic disease. In a nearly four year study, utilizing a two drug regimen of Phentermine and Fenfluramine, behavior modification, diet and exercise, the initial optimistic results have not been sustained, with a one third drop out rate and a final average weight loss of only three pounds in those who were followed for the four years of the study. This drug combination appears to have an unacceptably high association with cardiac valvular disease and has been withdrawn from therapeutic use because of these potentially life threatening sequelae.
Dietary weight loss attempts (aka dieting) often cause depression, anxiety, irritability, weakness and preoccupation with food. The treatment goal for morbid obesity should be an improvement in health achieved by a durable weight loss that reduces life threatening risk factors and improves performance of activities of daily living. Temporary fluctuations of body weight from calorie restricted diets should be avoided.
Understanding Patient Selection Criteria for Bariatric Surgery
The option of surgical treatment should be offered to patients who are
- morbidly obese,
- well informed,
- acceptable operative risks.
Patient should be able to participate in treatment and long term follow-up.
Some patients with manifest psychopathology that jeopardises an informed consent and cooperation with long-term follow-up may need to be excluded from surgery.
A decision to elect surgical treatment requires an assessment of the risk and benefit in each case. Increased abdominal fat or “central obesity” (apple shaped as opposed to pear shaped) is an important risk factor associated with the major complications of obesity. Functional impairments associated with obesity are also important deciding factors for surgical treatment. An important conclusion of the 1991 National Institutes Consensus Development Conference Statement on the surgical treatment of obesity was that “patients judged by experienced clinicians to have a low probability of success with non-surgical measures, as demonstrated, for example, by failure in established weight control programs or reluctance by the patient to enter such a program, may be considered for surgical treatment”.
Patients whose BMI exceeds 40 are potential candidates for surgery if they strongly desire substantial weight loss, because obesity severely negatively impacts the quality of their lives. They must clearly and realistically understand how their lives may be changed after a bariatric surgery operation.
In certain circumstances, less severely obese patients (with BMI’s between 35 and 40) also may be considered for surgery. Included in this category are patients with high risk co-morbid conditions such as life threatening cardiopulmonary problems (e.g. severe sleep apnea, Pickwickian syndrome, obesity related cardiomyopathy, or severe diabetes mellitus). Other possible indications for patients with BMI’s between 35 and 40 include obesity-induced physical problems that are interfering with lifestyle (e.g. musculoskeletal or neurologic or body size problems precluding or severely interfering with employment, family function and ambulation).
END STAGE OBESITY SYNDROME
Some candidates for surgical treatment of severe obesity have such impaired health that they must be hospitalized pre-operatively and undergo treatment to improve their operative risk.
Summary of the Different Surgical Options Available
There are several types of restrictive and combined operations. Each one has its own benefits and risks.
TYPES OF RESTRICTIVE OPERATIONS
Purely restrictive operations only limit food intake and do not interfere with the normal digestive process. To perform the operation, doctors create a small pouch at the top of the stomach where food enters from the oesophagus.
At first, the pouch holds about 1 ounce of food and later may stretch to 2-3 ounces. The lower outlet of the pouch is usually about ½ inch in diameter or smaller. This small outlet delays the emptying of food from the pouch into the larger part of the stomach and causes a feeling of fullness. After the operation, patients can no longer eat large amounts of food at one time. Most patients can eat about ½ to 1 cup of food without discomfort or nausea, but the food has to be soft, moist, and well chewed. Patients who undergo restrictive procedures generally are not able to eat as much as those who have combined operations.
Purely restrictive operations for obesity include adjustable gastric banding (AGB) and vertical banded gastroplasty (VBG).
Adjustable gastric banding.
In this procedure, a hollow band made of silicone rubber is placed around the stomach near its upper end, creating a small pouch and a narrow passage into the rest of the stomach (figure 2). The band is then inflated with a salt solution through a tube that connects the band to an access port placed under the skin. It can be tightened or loosened over time to change the size of the passage by increasing or decreasing the amount of salt solution.
Vertical banded gastroplasty.
VBG uses both a band and staples to create a small stomach pouch. Once the most common restrictive operation, VBG is not often used today.
Advantages of Restrictive Bariatric Surgery
Restrictive operations are easier to perform and are generally safer than malabsorptive operations. AGB is usually done via laparoscopy, which uses smaller incisions, creates less tissue damage, and involves shorter operating time and hospital stays than open procedures. (See below for more information on laparoscopy.) Restrictive operations can be reversed if necessary, and result in few nutritional deficiencies.
Disadvantages of Restrictive Bariatric Surgery
Patients who undergo restrictive operations generally lose less weight than patients who have malabsorptive operations, and are less likely to maintain weight loss over the long term. Patients generally lose about half of their excess body weight in the first year after restrictive procedures. However, in the first 3 to 5 years after VBG patients may regain some of the weight they lost. By 10 years, as few as 20 percent of patients have kept the weight off. (Although there is less information about long-term results with AGB, there is some evidence that weight loss results are better than with VBG.) Some patients regain weight by eating high-calorie soft foods that easily pass through the opening to the stomach. Others are unable to change their eating habits and do not lose much weight to begin with. Successful results depend on the patient’s willingness to adopt a long-term plan of healthy eating and regular physical activity.
Risks of Restrictive Bariatric Surgery
One of the most common risks of restrictive operations is vomiting, which occurs when the patient eats too much or the narrow passage into the larger part of the stomach is blocked. Another is slippage or wearing away of the band. A common risk of AGB is breaks in the tubing between the band and the access port. This can cause the salt solution to leak, requiring another operation to repair. Some patients experience infections and bleeding, but this is much less common than other risks. Between 15 and 20 percent of VBG patients may have to undergo a second operation for a problem related to the procedure. Although restrictive operations are the safest of the bariatric procedures, they still carry risk—in less than 1 percent of all cases, complications can result in death.
Because combined operations result in greater weight loss than restrictive operations, they may also be more effective in improving the health problems associated with severe obesity, such as hypertension (high blood pressure), sleep apnea, type 2 diabetes, and osteoarthritis.
COMBINED RESTRICTIVE/MALABSORPTIVE OPERATIONS
Combined operations are the most common bariatric procedures. They restrict both food intake and the amount of calories and nutrients the body absorbs.
Roux-en-Y gastric bypass (RGB)
This operation, illustrated in figure 4, is the most common and successful combined procedure in the United States. First, the surgeon creates a small stomach pouch to restrict food intake. Next, a Y-shaped section of the small intestine is attached to the pouch to allow food to bypass the lower stomach, the duodenum (the first segment of the small intestine), and the first portion of the jejunum (the second segment of the small intestine). This reduces the amount of calories and nutrients the body absorbs. Rarely, a cholecystectomy (gall bladder removal) is performed to avoid the gallstones that may result from rapid weight loss. More commonly, patients take medication after the operation to dissolve gallstones. (See WIN’s fact sheet Dieting and Gallstones for more information.)
Biliopancreatic diversion (BPD).
In this more complicated combined operation, the lower portion of the stomach is removed (see figure 5). The small pouch that remains is connected directly to the final segment of the small intestine, completely bypassing the duodenum and the jejunum. Although this procedure leads to weight loss, it is used less often than other types of operations because of the high risk for nutritional deficiencies. A variation of BPD includes a “duodenal switch” (see figure 6), which leaves a larger portion of the stomach intact, including the pyloric valve that regulates the release of stomach contents into the small intestine. It also keeps a small part of the duodenum in the digestive pathway. The larger stomach allows patients to eat more after the surgery than patients who have other types of procedures.
Advantages of Combined Restrictive/Malabsorptive Operations
Most patients lose weight quickly and continue to lose for 18 to 24 months after the procedure. With the Roux-en-Y gastric bypass, many patients maintain a weight loss of 60 to 70 percent of their excess weight for 10 years or more. With BPD, most studies report an average weight loss of 75 to 80 percent of excess weight. Because combined operations result in greater weight loss than restrictive operations, they may also be more effective in improving the health problems associated with severe obesity, such as hypertension (high blood pressure), sleep apnea, type 2 diabetes, and osteoarthritis.
Disadvantages of Combined Restrictive/Malabsorptive Operations
Combined procedures are more difficult to perform than the restrictive procedures. They are also more likely to result in long-term nutritional deficiencies. This is because the operation causes food to bypass the duodenum and jejunum, where most iron and calcium are absorbed. Menstruating women may develop anemia because not enough vitamin B12 and iron are absorbed. Decreased absorption of calcium may also bring on osteoporosis and related bone diseases. Patients must take nutritional supplements that usually prevent these deficiencies. Patients who have the biliopancreatic diversion procedure must also take fat-soluble (dissolved by fat) vitamins A, D, E, and K supplements, and require life-long use of special foods and medications.
RGB and BPD operations may also cause “dumping syndrome,” an unpleasant reaction that can occur after a meal high in simple carbohydrates, which contain sugars that are rapidly absorbed by the body. Stomach contents move too quickly through the small intestine, causing symptoms such as nausea, bloating, abdominal pain, weakness, sweating, faintness, and sometimes diarrhea after eating. Because the duodenal switch operation keeps the pyloric valve intact, it may reduce the likelihood of dumping syndrome.
Risks of Combined Restrictive/Malabsorptive Operations
In addition to risks associated with restrictive procedures such as infection, combined operations are more likely to lead to complications. The risk of death associated with these types of procedures is lower for the gastric bypass (less than 1 percent of patients) than for the biliopancreatic diversion with duodenal switch (2.5 to 5 percent). Combined operations carry a greater risk than restrictive operations for abdominal hernias (up to 28 percent), which require a follow-up operation to correct. The risk of hernia, however, is lower (about 3 percent) when laparoscopic techniques are used.
The vertical sleeve gastrectomy is a restrictive form of weight loss surgery in which approximately 85% of the stomach is removed leaving a cylindrical or sleeve shaped stomach with a capacity ranging from about 60 to 150 cc.It is an irreversible procedure. Unlike many other forms of bariatric surgery, the outlet valve and the nerves to the stomach remain intact Though the stomach is drastically reduced in size, it functions norlmaly; there is no restriction on the food consumed ,only on the quantity.The hunger stimulating hormones are almost all eliminated.
Sleeve gastrectomy is usually performed on extremely obese patients, with a body mass index of 60 or more. So a two stage procedure would be performed in which the first is a sleeve gastrectomy, and the second a conversion into a gastric bypass or duodenal switch. Patients usually lose a large quantity of their excess weight after the first sleeve gastrectomy procedure alone, but if weight loss ceases the second step is performed.
In this procedure weight loss is generated solely through gastric restriction (reduced stomach volume). The stomach is divided vertically and more than 85% of it is removed. This part of the procedure is not reversible. The stomach that remains is shaped like a banana (or a sleeve) and measures from 2-5 ounces (60-150cc) depending on the discretion of the surgeon. The nerves to the stomach and the outlet valve (pylorus) remain intact. This is to preserve the functions of the stomach while the volume is reduced. . There is no intestinal bypass with this procedure, only stomach reduction.
Obesity is now well recognised as an increasing medical problem in most developed countries. It is generally caused by an excessive intake of calories in the form of an unhealthy and high fat diet together with an increasingly sedentary lifestyle with little or no physical exercise.
Along with this increased weight there has also been an increasing trend to try different diets which either do not work or are started only half heartedly. Failure is therefore common. However, the mainstay of treatment for being overweight is usually decreased intake of calories, an increase in physical activity followed by maintenance of a healthier lifestyle. For those who have tried and failed to lose weight in this way and for those who are either grossly overweight or who have specific health risks associated with their weight, surgery for obesity can be an option.
Obesity surgery can also be known as Bariatric Surgery, Lap Banding, Gastric Banding or Gastric Bypass Surgery. The exact type of procedure patients have depends on the general health of the patient, the extent of their obesity and on the surgical expertise available. Of course, for a surgical option to be considered, patients must be fit enough for anaesthesia.
Gastrectomy is the surgical removal of all or part of your stomach.
If part of your stomach is removed the procedure is known as a partial gastrectomy, if your whole stomach is removed it is known as a total gastrectomy.
Sleeve gastrectomy is usually performed on extremely obese patients, with a body mass index of 60 or more. and unable to reduce their ood intake . Sleeve gastrectomy aims to force one to lose weight by restricting the amount of food the stomach can hold.
Gastrectomy is performed under a general anaesthetic. Your stomach must be empty for the surgery, so you will not be allowed food or water for 6-8 hours before your surgery. A nasogastric tube (a tube passed through your nose down to your stomach) will be inserted to keep your stomach empty and prevent complications such as vomiting.
There are different surgical techniques for gastrectomy. In the most common, the surgeon makes an incision in the r upper abdomen and then removes all or part of the stomach. some surgeons use a technique called laparoscopy (similar to 'keyhole' surgery) where a small incisionis made and a a laproscope is inserted. A laproscope is a tiny video camera that allows the surgeon to see inside the abdomen on a video monitor. The surgeon will then make two or three additional small incisions, insert special surgical instruments through them and operate on the stomach through the incisions.
After removing all or part of the stomach, the surgeon reconstructs the digestive tract so that the patient is able to digest food as normal
So a two stage procedure would be performed in which the first is a sleeve gastrectomy, and the second a conversion into a gastric bypass or duodenal switch. Patients usually lose a large quantity of their excess weight after the first sleeve gastrectomy procedure alone, but if weight loss ceases the second step is performed.
In this procedure weight loss is generated soley through gastric restriction (reduced stomach volume). The stomach is divided vertically and more than 85% of it is removed. This part of the procedure is not reversible. The stomach that remains is shaped like a banana (or a sleeve) and measures from 2-5 ounces (60-150cc) depending on the discretion of the surgeon. The nerves to the stomach and the outlet valve (pylorus) remain intact. This is to preserve the functions of the stomach while the volume is reduced. . There is no intestinal bypass with this procedure, only stomach reduction.
Most patients can lose 70 to 80% of their excess body weight over 6-12 months with sleeve gastrectomy alone.
The new stomach continues to function normally so there are far fewer restrictions on the foods which patients can consume after surgery.The only restriction is the quantity of food eaten will be considerably reduced. This is one of the great advantages of the vertical gastrectomy.
Another advantage is that the removal of the majority of the stomach also results in the virtual elimination of hunger stimulating hormones produced within the stomach.
The greatest advantage of the vertical sleeve gastrectomy lies in the fact that it does not involve any bypass of the intestinal tract and patients do not therefore suffer the complications of intestinal bypass such as intestinal obstruction, anemia, osteoporosis, vitamin deficiency and protein deficiency.
It also makes it a suitable form of surgery for patients who are already suffering from anemia, Crohn's disease and a variety of other conditions that would place them at high risk for surgery involving intestinal bypass.
Finally, it is one of the few forms of weight loss surgery which can be performed laparoscopically in patients who are extremely overweight.
The main disadvantage of the vertical sleeve gastrectomy is that it does not always produce the weight loss which people would wish for and, in the longer term, can result in weight regain. This is true of any form of purely restrictive weight loss surgery, but is perhaps especially true in the case of the vertical gastrectomy.
Vitamin deficiencies are rare with this procedure because there is no intestinal bypass. However, the procedure is very restrictive so most surgeons recommend that patients take a multivitamin, calcium and possibly a B12 vitamin after surgery.
All patients undergoing weight loss surgery are at risk for weight regain. Those patients who maintain good dietary habits and exercise patterns are more likely to keep the weight off than those who do not exercise and who snack frequently.
The diet will progress over the first year. It usually starts with 2-4 weeks of liquid protein drinks and water. Patients gradually progress to thicker food items and by two months are able to eat seafood, eggs, cheese and other regular foods. The diet generally recommended is low calorie (500 per day), high protein (70gm per day), low fat (30 gm per day) and low carbohydrates (40 gm per day). The calorie intake increases over the first year and by 12 months many patients have achieved their goal weight and consume between 900 and 1500 calories per day. This final calorie intake depends on level of activity, age and gender(men can usually consume more calories and maintain their weight).
Possible Post Operative Complications
Stomach mucus irritation and swelling due to vomiting or antiinflammatory drug use - Wound infection - Blood loss after surgery may sometimes result.
How You Will Feel:
As with all surgery, the immediate period after can be emotional and uncomfortable. Although the incision and surgical site is small, recovering from surgery is both a physical and emotional task
How Long Will you stay in Hospital after your Obesity surgery?
5 Days as inpatient