Gastric bypass procedures (GBP) are any of a group of similar operations used to treat morbid obesity—the severe accumulation of excess weight as fatty tissue—and the health problems (comorbidities) it causes.
Bariatric surgery is the term encompassing all of the surgical treatments for morbid obesity, not just gastric bypasses, which make up only one class of such operations.
Facts at a glance
- Gastric bypass surgery is performed with keyhole surgery
- The surgery has a higher complication rate than Gastric banding surgery
- Weight loss is much faster than Gastric banding surgery
- Hospital stay is on average (7-10) days
- Return to work is usually with in (4) weeks
- Long term follow up is essential for nutritional monitoring
- No adjustments are required post operatively
A gastric bypass first divides the stomach into a small upper pouch and a much larger, lower "remnant" pouch and then re-arranges the small intestine to allow both pouches to stay connected to it. Surgeons have developed several different ways to reconnect the intestine, thus leading to several different GBP names. Any GBP leads to a marked reduction in the functional volume of the stomach, accompanied by an altered physiological and psychological response to food. The resulting weight loss, is typically dramatic, associated with markedly reduction in comorbidities.
Gastric bypass is indicated for the surgical treatment of morbid obesity, a diagnosis which is made when the patient is seriously obese, has been unable to achieve satisfactory and sustained weight loss by dietary efforts, and is suffering from co-morbid conditions which are either life-threatening or a serious impairment to the quality of life.
In the past, serious obesity was interpreted to mean weighing at least 100 pounds (45 kg) more than the "ideal body weight", an actuarially determined body weight at which one was estimated to be likely to live the longest, as determined by the life insurance industry. This criterion failed for persons of short stature.
In 1991, the National Institutes of Health sponsored a consensus panel whose recommendations have set the current standard for consideration of surgical treatment, the body mass index (BMI). The BMI is defined as the body weight (in kilograms), divided by the square of the height (in meters). The result is expressed as a number usually between 20 and 70, in units of kilograms per square meter.
The Consensus Panel of the National Institutes of Health (NIH) recommended the following criteria for consideration of bariatric surgery, including gastric bypass procedures:
- People who have a body mass index (BMI) of 40 or higher. Or,
- People with a BMI of 35 or higher with one or more related comorbid conditions.
The Consensus Panel also emphasized the necessity of multidisciplinary care of the bariatric surgical patient, by a team of physicians and therapists, to manage associated co-morbidities, nutrition, physical activity, behavior and psychological needs. The surgical procedure is best regarded as a tool which enables the patient to alter lifestyle and eating habits, and to achieve effective and permanent management of their obesity and eating behavior.
Since 1991, major developments in the field of bariatric surgery, particularly laparoscopy, have outdated some of the conclusions of the NIH panel. In 2004, a Consensus Conference was sponsored by the American Society for Bariatric Surgery (ASBS), which updated the evidence and the conclusions of the NIH panel. This Conference, composed of physicians and scientists of many disciplines, both surgical and non-surgical, reached several conclusions, amongst which were:
- Bariatric surgery is the most effective treatment for morbid obesity
- Gastric bypass is one of four types of operations for morbid obesity.
- Laparoscopic surgery is equally effective and as safe as open surgery.
- Patients should undergo comprehensive pre-operative evaluation, and have multi-disciplinary support, for optimum outcome.
The gastric bypass, in its various forms, accounts for a large majority of the bariatric surgical procedures performed. It is estimated that 200,000 such operations were performed in the United States in 2008. An increasing number of these operations are now performed by limited access techniques, termed "laparoscopy".
Laparoscopic surgery is performed using several small incisions, or ports, one of which conveys a surgical telescope connected to a video camera, and others permit access of specialized operating instruments. The surgeon actually views his operation on a video screen. The method is also called limited access surgery, reflecting both the limitation on handling and feeling tissues, and also the limited resolution and two-dimensionality of the video image. With experience, a skilled laparoscopic surgeon can perform most procedures as expeditiously as with an open incision — with the option of using an incision should the need arise.
Variations of the gastric bypass
Gastric bypass, Roux en-Y (proximal)
This variant is the most commonly employed gastric bypass technique, and is by far the most commonly performed bariatric procedure in the United States. It is the operation which is least likely to result in nutritional difficulties. The small bowel is divided about 45 cm (18 in) below the lower stomach outlet, and is re-arranged into a Y-configuration, to enable outflow of food from the small upper stomach pouch, via a "Roux limb". In the proximal version, the Y-intersection is formed near the upper (proximal) end of the small bowel. The Roux limb is constructed with a length of 80 to 150 cm (31 to 59 in), preserving most of the small bowel for absorption of nutrients. The patient experiences very rapid onset of a sense of stomach-fullness, followed by a feeling of growing satiety, or "indifference" to food, shortly after the start of a meal.
Gastric bypass, Roux en-Y (distal)
The normal small bowel is 600 to 1,000 cm (20 to 33 ft) in length. As the Y-connection is moved farther down the Gastrointestinal tract, the amount of bowel capable of fully absorbing nutrients is progressively reduced, in pursuit of greater effectiveness of the operation. The Y-connection is formed much closer to the lower (distal) end of the small bowel, usually 100 to 150 cm (39 to 59 in) from the lower end of the bowel, causing reduced absorption (mal-absorption) of food, primarily of fats and starches, but also of various minerals, and the fat-soluble vitamins. The unabsorbed fats and starches pass into the large intestine, where bacterial actions may act on them to produce irritants and malodorous gases. These increasing nutritional effects are traded for a relatively modest increase in total weight loss.
The gastric bypass procedure consists in essence of:
- Creation of a small, (15–30 mL/1–2 tbsp) thumb-sized pouch from the upper stomach, accompanied by bypass of the remaining stomach (about 400 mL and variable). This restricts the volume of food which can be eaten. The stomach may simply be partitioned (typically by the use of surgical staples), or it may be totally divided into two parts (also with staplers). Total division is usually advocated, to reduce the possibility that the two parts of the stomach will heal back together ("fistulize"), negating the operation.
- Re-construction of the GastrointestinalI tract to enable drainage of both segments of the stomach. The technique of this reconstruction produces several variants of the operation, which differ in the lengths of small bowel used, the degree to which food absorption is affected, and the likelihood of adverse nutritional effects.
Costs can vary according to your particular private health cover, but a ball park figure is around $6500.00 out of pocket after all Medicare and Private Health cover rebates. It is possible to fund this out of pocket cost from your Superannuation, call us to enquire how.
What hospitals do we operate at for this procedure?
• The Avenue Private
• The Alfred Hospital
What appointments are required prior to surgery?
• (2) weeks prior you will have a consultation with the dietitian
• (2) weeks prior you will have a consultation with our counsellor
• (1) week prior a consultation with the pre-admission nurse of the hospital
• (1) week prior a final consultation with your surgeon
What appointments will I need following surgery?
We will make an appointment for you to have a consultation with our dietitian around the 2-3 weeks post surgery to discuss you dietary requirements.
An anastomosis is a surgical connection between the stomach and bowel, or between two parts of the bowel. The surgeon attempts to create a water-tight connection by connecting the two organs with either staples or sutures, either of which actually makes a hole in the bowel wall. The surgeon will rely on the healing power of the body, and its ability to create a seal like a self-sealing tire, to succeed with the surgery. If that seal fails to form, for any reason, fluid from within the gastrointestinal tract can leak into the sterile abdominal cavity and give rise to infection and abscess formation. Leakage of an anastomosis can occur in about 2% of gastric bypass procedures, usually at the stomach-bowel connection. Sometimes leakage can be treated with antibiotics, and sometimes it will require immediate re-operation. It is usually safer to re-operate if an infection cannot be definitely controlled immediately.
As the anastomosis heals, it forms scar tissue, which naturally tends to shrink ("contract") over time, making the opening smaller. This is called a "stricture". Usually, the passage of food through an anastomosis will keep it stretched open, but if the inflammation and healing process outpaces the stretching process, scarring may make the opening so small that even liquids can no longer pass through it. The solution is a procedure called gastroendoscopy, and stretching of the connection by inflating a balloon inside it. Sometimes this manipulation may have to be performed more than once to achieve lasting correction.
Ulceration of the anastomosis occurs in 1-16% of patients. Five possible causes of such ulcers are:
- Restricted blood supply to the anastomosis (compare to the blood supply available to the original stomach)
- Anastomosis tension
- Gastric acid
- Helicobacter pylori
- Use of Non-steroidal anti-inflammatory drugs
This condition can be treated as follows:
- Use of Proton pump inhibitors, e.g., Nexium
- Use of a Cytoprotectant and acid Buffering agent, e.g., Sucralfate
- Temporary restriction of the consumption of solid foods
Normally, the pyloric valve at the lower end of the stomach regulates the release of food into the bowel. When the Gastric Bypass patient eats a sugary food, the sugar passes rapidly into the bowel, where it gives rise to a physiological reaction called dumping syndrome. An affected person feels his heart beating rapidly and forcefully, breaks into a cold sweat, gets a feeling of butterflies in the stomach, and has a "sky is falling" type of anxiety. He/she usually has to lie down, and is very uncomfortable for about 30 to 45 minutes. Diarrhea may then follow.
Long term vitamin deficency
Approcimately 30% of patients with a gastric bypass surgery may develop vitamin B12, folate deficency.
It is essential to be monitored in multidisciplinary bariatric clinic life long
- Long term maintenance weight loss
- Possible control or remission of serious illness associated with obesity including:
- Raised Blood Pressure
- Sleep Apnoea
- Improved Quality of life, relinquish of stress of always being on a diet
- Able to participate in family activities eg swimming, playing sport chasing the kids