adjustable gastric banding

The  adjustable gastric banding has become popular since 1985 as a mean of achieving gastric restriction and treating morbid obesity. Adjustable  gastric banding (AGB) as described by Kuzmak  and the Swedish adjustable gastric band (SAGB) proposed by Hallberg permits gastric restriction. 

The adjustable band is placed around the top part of the stomach, leaving a small section of stomach (about 25 ml) above the band; the main part of the stomach lies below the band. A small passage is left open through the section of stomach surrounded by the band, so that liquids and food can still flow through from the upper to the lower part of the stomach. This small opening is called the stoma.

WHAT ARE THE ADVANTAGES OF THE ADJUSTABLE GASTRIC BAND?

This method is:

1. less invasive surgical intervention available for the treatment of morbid obesity, as no alterations are made to the anatomy of the stomach or intestines.
   
2. the only method which enables a perfect calibration of the stoma diameter and pouch size (small part of the stomach which remains above the band).
   
3. the only method where the width of the stoma can be modified postoperatively without further surgery.
   
4. the only totally reversable method in obesity surgery, in which the anatomy of the stomach is entirely restored to its original form, after the band is removed.
   

Average weightloss obtained with the laparoscopic adjustable gastric band is comparable to traditional surgical methods.

The percentages listed below represent average excess body weight loss over a period of 5 years.

• 3 months: 20% (excess body weight loss)
  
• 6 months: 20-40%
  
• 1 year: 58%
  
• 4 years: 65%.
  

It is of course essential that you comply with:

• medical advices
  
• dietary instructions
  
• follow-up controls
  
• exercising
  

You must meet the following criteria :

• You are at least 80% above your ideal weight (equivalent to approx. 45 kg or 100 lbs excess body weight or a Body Mass Index  - BMI of 40 or greater)
  
• You do not suffer from any other illness that cause obesity.
  
• You are prepared to modify your lifestyle and attend follow-ups regularly.
  

These are the basic criterias, but other requirements can be considered too, according to the results of the individual consultation.

You will be admitted to the hospital a couple of days before your operation. The actual operation is performed under full anaesthesia. The band is placed around the stomach and the injection port is fixed to the stomach muscle or on the breast bone. Immediately after your operation you will be given new eating rules and be asked to introduce as much excersize into your daily routine as possible. The length of your hospital stay will depend upon your progress, approximately 3-4 days after the operation. After leaving the hospital it is important that you follow the instructions given to you by your doctor very carefully.

The Adjustable Gastric Band (AGB) operation is the first step towards a major readjustment of the patient`s lifestyle. The patient has to learn  new eating behaviours.

The following 6 rules are very important eating habits:

1. Only eat small quantities: The capacity of the stomach has changed. Also the amount of food intake has to change. Nevertheless it is not always easy to stop eating at the right time. What do we mean, if we say small quantities? For example one slice of bread for breakfast or 2 potatoes and a small piece of fish for lunch.
   
2. Chew well and swallow food only completely mashed: You need more time for chewing and also not all food is possible to chew well. The list of “unsuitable food” will show you the products which are usually not easy to chew.
   
3. Never eat and drink at the same time: The reduced capacity of the first part of the stomach will no longer permit to take in both: liquid and food at the same time. The usual amount of beverage, 2-3 litre liquid per day, are desirable. It´s better to drink between or before meals.
   
4. Do not lay down or rest after eating: because in a horizontal position reflux is more likely. The food also remains longer in the prestomach and leads to a very uncomfortable accumulation of mucus.
   
5. Eat five times a day: This is important, because if you only eat 2-3 times a day, it is not possible to have a great variety of food. Consequently, as you can only eat small amounts, you do not get enough proteins, minerals and vitamins. In addition, when eating 5 times daily, it is less likely that you are overpowered by sudden hunger attacks where you probably forget the new eating habits.
   
6. Watch for beverages rich in calories: In our experience, many people take in a lot of their calories with soft drinks, hot chocolate and milk shakes. This is also possible after the operation, so consider this before drinking high calorie liquids. The type of liquid should be varied and include tea or coffee, diluted fruit- or vegetable juice, light drink with artificial sugar, low fat variants of butter milk, mineral water without gas. 
   

Certain food are not easily tolerated and should be avoided unless they can be broken down into easily digestible alternatives. These are foods, that generally get stuck in the opening of the stomach and are therefore likely to cause obstruction, and include vomiting and fluid depletion.

Unsuitable food are:

• tough meet, especially beef
  
• pastas and noodles
  
•  vegetables with shell or skin (beans, corn, peas, asparagus)
  
• mushrooms
  
• sausages and bacon
  
• fruit with peel or skin e.g. grapes
  
• carbonic acid
  

It is, therefore, advisable to avoid eating meat in the beginning and only introduce this progressively into the diet. Much depends on how much fluid is injected into the AGB`s balloon as this affects the size of the aperture between the upper und lower part of the stomach. A small hole will allow greater weight loss, but will also require that patients are more careful about what they eat. With the balloon totally empty, the patient will be able to eat almost normally.

The great advantage of gastric banding is that the band’s width can be altered postoperatively. The stoma (the small passage through the stomach where it is surrounded by the band and through which food passes from the upper to the lower part of the stomach) diameter can be adjusted if weight loss has slowed down too much or if you find you are able to eat a lot of food in a small period of time. The stoma diameter is widened if you are only able to swallow liquids or if you frequently need to vomit.

As with any important surgical intervention, the normal risks encountered with surgery also apply to gastric banding. It is not always possible to perform gastric banding by keyhole surgery, in this case the intervention is converted to traditional open surgery.

The risk of postoperative complications average out between 3-5%. This includes infections, pneumonia or bleeding. Severely overweight patients run a higher risk of incurring operative complications. The risk of mortality is, according to literature, below 0.3%.

It is also possible to regain weight after some time, because snacks and high calorie food could make the band ineffective.

The main goal is to make radical changes in your lifestyle after gastric banding. You must learn to have five meals a day and no snacks in between. Also, high calorie drinks such as coca cola, ice-tea or any other soft drinks must be avoided.

Possible risks specific to gastric banding and their frequency according to statistical data found in the literature and in our series:

• Stomach mucus irritation and swelling due to pressure of the band onto the stomach and migration of the band through the stomach wall: 0.6%
  
• Leakage from the tube and balloon: 1.8%
  
• Wound infection in the area of the injection port: 0.3%
  
• The need to reoperate: 6%
  

Laparoscopic AGB is performed in our center since 1994, 99 % of the patients had a gastric band fitted by keyhole surgery in our hospital (3 patients had a laparotomy). Significant longterm weightloss is achieved in 90 % of all patients (Zentr. Chir. 2002). The only early postoperative complications noted were linked to the removal of the gallbladder in one patient (0,2%), two pulmonary embolism and one pneumonia. Late complications have included six pouch dilatations and seven band leakages which necessitated the replacement of the band with a new operation. One patient died due to pulmonary embolism (mortality rate also in literature 0,3 %).

Our average complication rate is therefore 6% (pouch dilation, band leakage, etc). But – patients between 20 and 30 years with morbid obesity without any treatment have a 12 times higher mortality rate than people with normal weight. (Drenick EJ, et al. Jama 1980; 243: 443-445)

An infection may develop either in the port area or in the abdomen, and in some instances this may cause the band to migrate into the stomach. In such a case, reoperation may be necessary. Most of the complications linked to migrations have occurred as a result of too much fluid being injected into the AGB (Adjustable Gastric Band), which then causes too much pressure onto the stomach wall. The balloon must therefore be filled with no more than 9 ml of fluid, as recommended by Obtech Medical and no more than 4 ml in the Bioenterics LAP-Band. In nearly all of the reported cases of migration, the balloon had a fluid content above 11 ml. This is 2 ml more than the recommended maximum volume. This problem has now mostly been solved. The rate of migration will be kept low by avoiding overfilling the system. Migration can also be caused by a subclinical infection.

Leakage from the AGB or from the connecting tube between the balloon and the port may require reoperation. The balloon is made of fragile material, and leakage can occur either shortly after surgery or many years later. In the event of leakage, the AGB can normally easy be replaced with a new one. Nowadays this is a rare complication but you must be aware that experience using the SAGB dates back to 1985 only and therefore there is a possibility that in the very long term the band may need to be replaced with a new one.

The band may slip, and the pouch (the part of the stomach above the band) may become too enlarged, and a reoperation may be necessary. This is nowadays a rare complication due to a better operating technique.

The injection port may dislocate. When injecting into the port, there is always the risk of puncturing the silicone tube. Post dislocations can be corrected with a small operation under local anaesthesia.

There may be other rare, unspecified complications. You should ask your doctor for more detailed information. There is no guarantee that the AGB will work without fault for the rest of your life, however, extensive use of the AGB since 1985 has lead to a method where failure is rare. In most patients, the AGB works well and provides an essentially complication-free and long-term weight loss. You must understand that the possibility of reoperation is an integral part of the procedure. The overall rate of reoperation following the placement of an AGB is low (3-9 %) and problems can usually be corrected and patients are generally rapidly back on track after such treatment.

Patients occasionally vomit or feel pain after food intake. This can be caused either by poor eating behaviour, or by the narrow passage of the AGB following the injection of fluid into the balloon. By eating slowly and carefully, you will learn to listen to the signals from your stomach. Regular vomiting is definitely a warning sign. In such cases, the amount of liquid in your AGB may need to be readjusted.

During the phase of rapid weight reduction, vitamin supplements are advisable. A liquid vitamin mixture containing multivitamins, in particular the vitamin B complex, is recommended for at least the first 6 months following surgery.

The period between surgery and weight stabilisation is considered as a period of starvation. It is not advisable to become pregnant during starvation, because the fetus needs a good food supply. Should you nevertheless get pregnant it is advisable to remove all the fluid from the band. Pregnancy is never a risk in patients with AGB but follow-ups and controls are necessary.

Tablets must be broken down into small pieces or crushed before they are taken. It is common that medication for conditions such as hypertension, diabetes or asthma may need to be altered (reduced) after this operation. Patients should consult their doctors in this matter.

Many patients feel constipated after surgery. This is mainly due to the fact that the reduced food intake leads to less faeces and thus to fewer bowel movements. If laxatives become necessary, it is advisable to abstain from so-called bulking agents and instead use liquid laxatives, such as lactulose

After surgery you must undergo regular outpatient check-ups. Initially, these check-ups will be carried out monthly, but soon visits will become less frequent. The AGB will gradually be filled via the injection port during the first 18 months following surgery. During this period, your weight loss and level of well-being will be monitored. Once your weight has stabilized, check-ups will be necessary on an annual basis.

It will be important to alter not only your eating habits, but also your level of physical activity. Patients are generally recommended to start exercising slowly. As weight loss is achieved, physical activities will gradually become easier.