Adjustable gastric band

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Adjustable gastric banding is a form of restrictive weight loss surgery (bariatrics) designed for obesity patients with a body mass index (BMI) of 40 or greater - or between 35 – 40 with those who have co-morbidities that are known to improve with weight loss. The gastric band is an inflatable silicone prosthetic device which is placed around the top portion of the stomach via keyhole surgery laparoscopic surgery.

Contents

[edit] Theory of Gastric Banding

The placement of the band creates a small pouch at the top of the stomach which holds approximately 50mls. This pouch 'fills' with food quickly and the passage of food from the top to the bottom of the stomach is slowed. As the upper part of the stomach believes it is ‘full’ the message to the brain is that the stomach is full and this sensation helps the person to eat smaller portions, eat less and therefore lose weight over time.

The band is inflated /adjusted via a small access port placed just under the skin subcutaneous. Radio opaque isotonic solution or saline is introduced into the band via the port. A specialized needle is used to avoid damage to the port membrane. There are many port designs and they may be placed in varying positions based on the surgeon’s preference. The port may be sutured in place. When fluid is introduced the band expands placing pressure around the outside of the stomach. This decreases the size of the passage in the stomach and restricts the movement of food.

Over a period of time, restriction is increased until patients feel they have reached a “sweet spot” where optimal weight loss can be reached with the minimal fluid required. This is an individual experience and timing cannot be predicted. There are approximately 7 - 8 adjustable bands on the market the amount of fluid required and total content is varied.

If considering pregnancy ideally the patient should be in optimum nutritional status prior to conception and deflation of the band may be required prior to planned conception. This is also to be considered should morning sickness be present. The band may remain deflated during pregnancy and once breast feeding (or if bottle feeding 6/52 approx) is completed the band may be gradually re-inflated to aid post partum weight loss if needed. [citation needed]

Gastric band placement, unlike traditional malabsorbative weight loss surgery e.g. Roux-en-Y gastric bypass surgery (RNY), Biliopancreatic Diversion (BPD_ and Duodenal Switch (DS), does not cut, mutilate, or remove any part of the digestive system. Removal would require a keyhole procedure and the stomach would return to it normal pre-banded state. Unlike those who have procedures such as RNY, DS or BPD it is unusual for gastric band patients to experience any nutritional deficiencies or malabsorption of micro nutrients. Calcium suppliments and Vitamin B12 injections are not routinely required following Gastric banding (they are with e.g. RNY). Gastric dumping syndrome issues also do not occur since no intestines are removed or re-routed.

Initial weight loss is slower than e.g. RNY, however, statistics indicate that over a 5 year period the weight loss outcome is similar / the same.[citation needed] Weight regain is possible with ANY weight loss procedures including the more radical procedures that initially result in rapid weight loss. World Health Organisation recommendation for monthly weight loss is ½ to 1 kilograms per week and an ‘average’ banded patient may lose this.[citation needed] Clearly this is variable to the individual, their personal circumstances, motivation and mobility ability.

A common reported occurrence for banded patients is regurgitation of non-acidic swallowed food from the upper pouch, commonly known as PB’ing (Productive Burping).[citation needed] Productive Burping is not to be considered normal. The patient should consider eating less, eating more slowly, or chewing their food more thoroughly. Occasionally the narrow passage into the larger / lower part of the stomach may become blocked by a large portion of unchewed or unsuitable food stuff.[citation needed]

Further potential complications include

• prosthetic fault (e.g. a leak) [citation needed]

• Physical damage – Erosion - the band may wear a small area on the outside of the stomach which can lead to Migration of the band to the inside the stomach. Slippage- an unusual occurrence where the lower part of the stomach may prolapse over the band and cause an obstruction. [citation needed]

• Psychological effect of any weight loss procedure must not be ignored. [citation needed]

[edit] History of the procedure and device

The first gastric band was patented in 1985 by Obtech Medicalof Sweden (now owned by J&J/Ethicon Endo-Surgery)and is known as the Swedish Adjustable Gastric Band (SAGB). An American company, INAMED Health, later designed the BioEnterics ® LAP-BAND ® Adjustable Gastric Banding System. The LAP-BAND® System was introduced in Europe in 1993. The Swedish band was not designed for use with keyhole surgery whereas the LAP-BAND specifically was. Another difference was that the SAGB didn't have a self-closing mechanism and had to be sutured closed. The LAP-BAND System received Food and Drug Administration approval for use in the United States in June 2001.In 2000 the first lower pressure, wider and one piece adjustable gastric band the MIDband ® was placed in Lyon France Medical Innovation Development[1] Unlike many of the early bands this was designed specifically for laparoscopic insertion. It has swiftly become one of the leading bands placed in France. There are now many band manufacturers (approx 7-8 in total)

[edit] Indications

In general, gastric banding is indicated for people for whom all of the following apply:

  • Body Mass Index above 40, or those who are 100 pounds (45 kg). or more over their estimated ideal weight according to the 1983 Metropolitan Life Insurance Tables or those between 30 to 40 with co-morbidities which may improve with weight loss (high blood pressure, diabetes, sleep apnea, and arthritis).
  • Age between 18 and 55 years (although there are doctors who will work outside these ages).
  • Failure of dietary or weight-loss drug therapy for more than one year
  • History of obesity (generally 5 years or more).
  • Comprehension of the risks and benefits of the procedure and willingness to comply with the substantial lifelong dietary restrictions required for long term success.
  • Acceptable operative risk.

It is usually contraindicated for people with any of the following:

[edit] Gastric banding as an alternative to other weight loss surgeries

  • Lower mortality rate, only 1 in 2000 versus 1 in 200 for Roux-en-Y gastric bypass surgery
  • Fully reversible, stomach returns to normal if the band is removed
  • No cutting or stapling of the stomach
  • Short hospital stay
  • Quick recovery
  • Adjustable without additional surgery
  • No malabsorption issues (because no intestines are bypassed)
  • Fewer life threatening complications (see complications table for details)

[edit] Losing weight after surgery

Correct and sensitive adjustment of the band is imperative to weight loss and the long term success of the procedure. Adjustments (also called "fills") may be performed using X ray fluoroscope so that the Radiologist may assess the placement of the band, the port and the tubing which runs between the port and the band. The patient is given a small cup of a liquid containing a radio opaque fluid similar to barium – clear or white. When swallowed, the fluid is clearly shown on X –ray and is watched as it travels along the gut and through the restriction caused by the band. The Radiologist is then able to see the level of restriction in the band and to assess if there are potential or developing issues of concern. These may include dilation of the oesophagus, an enlarged pouch, prolapsed stomach (when part of the stomach moves into the band where it does not belong), erosion or migration. Reflux type symptoms may indicate too greater a restriction and further investigation would be required. In some circumstances fluid would be removed from the band prior to further investigations and re evaluation. In some cases further surgery may be required e.g. removal of the band should gastric erosion or similar be detected.

Some health practitioners adjust the band without the use of X ray control (fluoroscopy) e.g. this is standard practice in the main bariatric surgery clinic in Melbourne, Australia, where AGB placement has been performed for more than ten years. Also in some UK services e.g. Bristol. In these cases, patients visiting for a regular fill adjustment will typically find they will spend more time talking about the adjustment and their progress than the actual fill itself, which generally will only take about 60 seconds to two minutes.

For some patients this type of fill is not possible, for example due to partial rotation of the port, or excess tissue above the port making it difficult to determine its precise location, in which case a fluoroscope will generally be used.

No accurate number of adjustments required can be given. However, an average may be estimated to be between three and five fills (where saline/ isotonic solution is inserted into the band via the subcutaneous port) for a person to reach the optimal restriction for weight loss. The amount of saline/ isotonic solution needed in the band varies from patient to patient. There are a small number of people who find they do not need a fill at all and have sufficient restriction immediately following surgery. Others may need significant adjustments to the maximum the band is able to hold. Bands come in several diameters and sizes and can hold a total of between 4 ccs (mls) to 12 ccs (mls) of fill fluid depending on the design. Band preference is usually determined by personal preference of the surgeon who places the band together with what he is either able to use (e.g., specific bands approved in country of surgery) or what s/he believes to be the most appropriate. In Europe e.g. it is possible for the surgeon to use many designs. The size of the band used is determined by the surgeon during surgery based on the size and thickness of the patient's stomach.

It is more common practice for the band not to be filled at surgery – although some surgeons chose to place a small amount in the band at the time of placement. The stomach tends to swell following surgery and it is possible that too great a restriction would be achieved if filled at the time of surgery clearly this is undesirable.

The patient may be prescribed a liquid only diet, followed by mushy foods and then solids. This is prescribed for a varied length of time and each surgeon and manufacturer varies. Some may find that that before their first fill that they are still able to eat fairly large portions. This is not surprising since before the fill there is little or no restriction and is why a proper post-op diet and a good after-care plan is essential to success. Many health practitioners make the first adjustment between 6 – 8 weeks post operatively to allow the stomach time to heal. After that fills are performed as needed. Some practitioners may be more aggressive than others, but most appear to require a 2-4 week wait between fills. It is very important to discuss post-surgical care and diet plans with your weight loss team if you are considering this surgery. Recommendations can vary dramatically from team to team and it is important to find a weight loss team with a good post-surgical plan. Some teams offer support groups, but unfortunately many of them mix RNY patients with gastric banding patients. Some gastric band patients have criticized this approach because while many of the underlying issues related to obesity are the same, the needs and challenges of the two groups are very different, as are their early rates of weight loss. Some gastric band recipients feel the procedure is a failure when they see that RNY patients generally lose weight faster.

The average gastric banding patient loses 500 grams to a kilogram (1-2 pounds) per week consistently, but heavier patients often lose faster in the beginning. This comes to roughly 50 to 100 pounds the first year for most band patients. It is important to keep in mind that while they drop the weight faster in the beginning, most of the RNY patients will have the same percentage of excess weight loss and comparable abilities to keep it off after only a couple of years. Gastric banding patients may have to work a little harder in the first couple of years, but the procedure tends to encourage better eating habits which help in producing long term weight stability.

[edit] The LAP-BAND in Australia

According to an August 2006 article in The Medical Journal of Australia [2], over 90% of weight loss surgeries in Australia are installations of the laparoscopic adjustable gastric band. Some of the more interesting findings in the study are these:

Our group has treated more than 2700 severely obese patients with the LAGB procedure since 1994 without a single perioperative death. In contrast, mortality from RYGB is reported at between 0 and 5%, with the ASERNIP-S systematic review showing a mean short-term mortality rate of 0.5% — ten times the risk of LAGB. [...]

All bariatric procedures have been able to achieve loss of more than 50% of excess weight. The ASERNIP-S systematic review showed greater weight loss after RYGB than LAGB during the first 2 years after the procedure, but the difference in weight loss was not significant at 3 and 4 years. In a recent review, we extended the data of the ASERNIP-S review by including all studies that included at least 50 patients, reported up to March 2004. This showed a substantial weight loss after both procedures, with an initial greater weight loss after RYGB but similar effectiveness for both procedures at 4, 5 and 6 years.

[edit] Documented adverse effects

From the FDA website

[edit] Band & Port Specific

  • Band slippage/Pouch dilation
  • Esophageal dilatation/dysmotility
  • Erosion of the band into the gastric lumen
  • Mechanical malfunctions - port leakage, cracking of the kink-resistant tubing or disruption of the tubing connection from the port to the band
  • Port site pain
  • Port displacement

[edit] Digestive

[edit] Body as a whole

[edit] Miscellaneous

[edit] Celebrities

As with many developments in approaches to weight loss, some high-profile and well-publicized cases amongst celebrities have increased the public awareness of gastric banding:

[edit] Manufacturers

  • MID Medical Innovation Development - MIDband®
  • INAMED Health - The BioEnterics® LAP-BAND® System
  • Ethicon Endo-Surgery (formerly Obtech Medical) - Swedish Adjustable Gastric Band (SAGB). Ethicon Endo-Surgery is a division of Johnson & Johnson and acquired Obtech, manufacturer of the SAGB.

[edit] External links and references

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