Theory of gastric banding


Gastric banding should not be considered an easy option for obesity sufferers. It is a serious step, and is associated with pain and risks similar to other intermediate abdominal surgical operations such as gall bladder removal. However, consisting primarily of the addition of a (removable) implant system, it is considerably less risky than permanent surgical rearrangement of the gastrointestinal tract. Most patients who undergo adjustable gastric band surgery lose approximately 60% of their excess body weight (the weight in excess of their "ideal body mass"). Typically, patients who undergo adjustable gastric banding procedures, such as Lap-Band or RealizeBand lose less weight over the first 3.5 years than those who have a gastric bypass or sleeve resection, or other surgeries such as biliopancreatic diversion (BPD) and/or Duodenal Switch (BPD-DS). However, over 7 to 8 years, weight loss from gastric banding and bypass are essentially equal according to the American College of Surgeons. However, in order to maintain this type of weight reduction, patients must follow carefully the post-operative guidelines relating to diet, exercise, and band maintenance.

The placement of the band creates a stoma, or small pouch at the top of the stomach that holds approximately 110 to 220 grams of food each meal. This pouch fills with food quickly and the band slows the passage of food from the pouch to the lower part of the stomach. As the upper part of the stomach registers as full, the message to the brain is that the entire stomach is full and this sensation helps the person to be hungry less often, to feel full more quickly and for a longer period of time, to eat smaller portions, and lose weight over time.

The gastric band is inflated/adjusted via a small access port placed just under the skin. Saline solution is introduced into the gastric band via the port. A specialized non-coring [Huber point] needle must be used to avoid damage to the port membrane. There are w different port designs (such as high profile and low profile) and they may be placed in varying positions near the left rib margin based on the surgeon’s preference. The port is usually sutured or, in the case of the RealizeBand, stapled into place, although some surgeons prefer to omit this step. When saline is introduced into the band it expands, placing pressure around the outside of the uppermost part of the stomach, and thereby creating a small pouch. This pouch has a very limited capacity for food and when full will cause the patient to feel satiated. If food intake continues beyond the capacity of the pouch (usually less than 40 cc), the patient will usually be forced to regurgitate the excess (due to the gastric band restricting the passage in to the rest of the stomach, the pouch can only empty at a slow rate). Gastric Bands systems usually hold up to 14 cc of saline depending on model and manufacturer's specifications.

Over the course of several visits to the doctor, the band is filled to an extent where the patient feels he or she has found what is colloquially known as the “sweet spot” or "green zone", where optimal restriction has been achieved, neither so loose that food intake is not controlled, nor so tight that little or no food and fluids will pass. This is an individual experience and cannot be predicted. There are around half a dozen makes of gastric band on the market, although the best known are produced by Allergan (Lap-Band) and Ethicon (Realize). Increasingly, the procedure is followed by a web-based patient education and follow-up programme. Gastric band patients ("bandsters") often frequent Weight Loss Surgery (WLS) support websites which offer information and advice via blogs and bulletin boards.

Pregnancy
If considering pregnancy, ideally the patient should be in optimum nutritional condition prior to, or immediately following conception; deflation of the band may be required prior to a planned conception. Deflation should also be considered should morning sickness be present. The band may remain deflated during pregnancy and once breast feeding is completed, or if bottle feeding, the band may be gradually re-inflated to aid postpartum weight loss as needed. [citation needed]

Comparison with other bariatric/weight loss surgery techniques
Gastric band placement, unlike malabsorptive weight loss surgery (e.g. Roux-en-Y gastric bypass surgery (RNY), biliopancreatic diversion (BPD) and Duodenal Switch (DS)), does not cut or remove any part of the digestive system. If indicated, it is usually easy to remove the band and reverse the surgery, requiring only a laparoscopic procedure, after which the stomach usually returns to its 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 supplements and Vitamin B12 injections are not generally required following gastric banding (as they are with RNY, for example). Gastric dumping syndrome issues also do not occur since no component parts of the intestines are removed or re-routed. The techniques of stomach stapling and sleeve gastrectomy (where approximately half of the stomach is either "sidelined" or removed) are making a comeback in some centres after having falling out of use during the last decade due to a high complication rate; their impact on food passage is comparable to gastric banding. Current proponents of this surgical approach claim weight loss and complication outcomes similar to gastric banding. Gastric banding is practically always performed as a laparoscopic technique (resulting in shorter hospital stay), whereas this is less often the case for RNY, BPD and DS.

With gastric banding, initial weight loss is slower than with RNY, generally 450 - 900 grams per week; however, statistics indicate that over a 5-year period, weight loss outcome is similar.[citation needed] Weight regain is possible with ANY weight loss procedures including the more radical procedures that initially result in rapid weight loss. The World Health Organization recommendation for weight loss is 1⁄2 to 1 kilogram per week and an average banded patient may lose this amount.[citation needed] Clearly this is variable based on the individual and their personal circumstances, motivation, and mobility. The restriction imposed by the band generally needs to be greater for the initial weight loss phase and less for the subsequent weight maintenance phase. However as the patient loses weight, the internal organs (including the stomach) also shrink, and band system fill may need to be increased slightly. It should be emphasised that bandsters require ready access to a clinic where fill adjustments can be made; most patients will have between 5 and 15 fill adjustments over the lifetime of their band.

A commonly reported occurrence for banded patients is regurgitation of swallowed food and/or saliva from the pouch, commonly known as Productive Burping (PBing).[citation needed] There is argument ongoing about whether productive burping is to be considered normal or not - many bandsters feel that restriction is unlikely to be sufficient for significant weight loss unless PBing is experienced at least occasionally. 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 foodstuff.

]Potential complications

• Gastritis (irritated stomach tissue) causing diffuse discomfort or pain; if severe this may result in actual ulcer formation

• Erosion - The band may slowly migrate through the stomach wall to the inside. This may occur silently but usually causes symptoms similar to the above. Urgent medical/surgical treatment will be required if there is any internal leak of gastric contents, or bleeding.

• Slippage - An unusual occurrence in which the lower part of the stomach may prolapse through the band causing an enlarged upper pouch. In severe instances this can cause an obstruction and require an urgent operation to fix.

• Malposition of the band - This can cause a kink in the stomach, or (rarely) the band may not encircle the stomach at all, giving no restriction to the passage of food.

• Problems with the port and/or the tube connecting port and band - The port can "flip over" so that the membrane can no longer be accessed with a needle from the outside (this often goes hand in hand with a tube kink, and may require repositioning as a minor surgical procedure under local anaesthesia); the port may get disconnected from the tube or the tube may be perforated in the course of a port access attempt (both would result in loss of fill fluid and restriction, and likewise require a minor operation).

• Internal bleeding

• Infection

The band lifetime combined incidence of all complications is of the order of 10%.

The psychological effects of any weight loss procedure also must not be ignored, as a proportion of patients fail to lose weight (often because they subconsciously develop strategies to defeat the band and maintain their status quo which they have become psychologically habituated to). Continued counselling, dietary advice and interaction with WLS support groups - locally and/or on the web - is widely seen as being of considerable help to patients, and can make the difference between success and failure. Many patients perceive themselves as having previously failed at every other weight loss strategy, and consequently their trigger threshold for giving up on WLS is often low, even after substantial financial commitment.

History and development
Non-adjustable bands
At the end of the 1970s, Wilkinson developed several surgical approaches whose common aim was to limit food intake without disrupting the continuity of the gastro-intestinal tractb

In 1978 Wilkinson and Peloso were the first to place, by open procedure, a non-adjustable band (2 cm Marlex mesh) around the upper part of the stomach.

The early 1980s saw further developments, with Kolle (Norway), Molina & Oria (US), Naslund (Sweden), Frydenberg (Australia) and Kuzmack (United States) implanting non-adjustable gastric bands made from a variety of different materials, including marlex mesh, dacron vascular prosthesis, silicone covered mesh and Gore-Tex, among others. In addition, Bashour developed the “gastro-clip” a 10.5 cm polypropylene clip with a 50cc pouch and a fixed 1.25 cm stoma, which was later abandoned due to high rates of gastric erosion.

All these early attempts at restriction using meshes, bands and clips showed a high failure rate due to difficulty in achieving correct stomal diameter, stomach slippage, erosion, food intolerance, intractable vomiting and pouch dilatation. Despite these difficulties, an important ancillary observation was that silicone was identified as the best tolerated material for a gastric device, with far fewer adhesions and tissue reactions than other materials. Nevertheless, adjustability became the “Holy Grail” of these early pioneers.

Adjustable bands
The development of the modern adjustable gastric band is a tribute both to the vision and persistence of the early pioneers, particularly Lubomyr Kuzmak and a sustained collaborative effort on the part of bio-engineers, surgeons and scientists.

Early research on the concept of band “adjustability” can be traced back to the early work of G. Szinicz (Austria) who experimented with an adjustable band, connected to a subcutaneous port, in animals.

In 1986, Lubomyr Kuzmak, a Ukrainian surgeon who had emigrated to the United States in 1965, reported on the clinical use of the “adjustable silicone gastric band” (ASGB) via open surgery. Kuzmak, who from the early 1980s had been searching for a simple and safe restrictive procedure for severe obesity, modified his original silicone non-adjustable band he had been using since 1983, by adding an adjustable portion. His clinical results showed an improved weight loss and reduced complication rates compared with the non-adjustable band he had started using in 1983. Kuzmak’s major contributions were the application of Mason’s teachings about VBG to the development of the gastric band; the volume of the pouch; the need to overcome staple line disruption; the ratification of the use of silicone and the essential element of adjustability.

Separately, but in parallel with Kuzmak, Hallberg and Forsell in Stockholm, Sweden also developed an adjustable gastric band. After further work and modifications this eventually became known as the Swedish Adjustable Gastric Band (SAGB).

The laparoscopic era
The advent of surgical laparoscopy transformed the field of bariatric surgery and made the gastric band an even more appealing option for the surgical management of obesity.

In 1992, Cadiere was the first to apply an adjustable band (the early Kuzmak ASGB) by the laparoscopic approach. In 1993, Broadbent in Australia and Catona in Italy, implanted non-adjustable (Molina-type) gastric bands by laparoscopy.

In the period between 1991–1993, the original Kuzmak ASGB underwent important research and design modifications in order to make it suitable for laparoscopic implantation, eventually emerging as the modern lap band. This landmark innovation was driven by Belachew, Cadiere, Favretti and O’Brien and the Inamed Development Company engineered the device. The first human laparoscopic implantation of the newly developed lap band was performed by Belachew and le Grand on 1st Sept 1993 in Huy, Belgium, followed on 8 September, by Cadiere and Favretti in Padua, Italy.

In 1994, the first international laparoscopic band workshop was held in Belgium and the first on the SAGB in Sweden.

Types of adjustable bands
In the US market, two types of adjustable gastric bands have been approved by the FDA: Realize Band and Lap-Band. The Lap-Band System (Allergan Inc., Irvine, CA) obtained FDA approval in 2001. The device comes in five different sizes and has undergone modification over the years. The latest models, the Lap-Band AP-L and Lap-Band AP-S, feature a standardized injection port sutured into the skin and fill volumes of 14 mL and 10 mL respectively.

The Realize Adjustable Gastric Band (Ethicon Endo-Surgery, Inc., Cincinnati, OH) obtained FDA approval in 2007. Realize Band-C has a 14% greater adjustment range than the Realize Band. But both the Realize Band and Realize Band-C are one-size-fits-all. The device differentiates itself from the Lap-Band AP series through its sutureless injection port installation and larger range of isostatic adjustments. The maximum fill volume for the Realize Band is 9mL, while the newer Realize Band-C has a maximum fill capacity of 11mL. Both fill volumes fall within a low pressure range to prevent discomfort or strain to the band.

Two other adjustable gastric bands are in use outside of the United States: Heliogast and Midband. Neither band has been approved by the FDA. The Midband (Médical Innovation Développement, Limonest, France) was the first to market in 2000. In order to preserve the gastric wall in event of rubbing, the device contains no sharp edges or irregularities. It is also opaque to x-rays, making it easy to locate and adjust.

The Heliogast band (Helioscopie, Rhône-Alpes, France) entered the market in 2003. The device features a streamlined band to ease insertion during the operation.

Swedish Adjustable Gastric Band - History of the procedure and device
In early 1985, Dr. Dag Hallberg applied for a patent for the Swedish Adjustable Gastric Band (SAGB) within Scandinavian countries. In late March, Dr. Hallberg presented his idea of the "balloon band" at the Swedish Surgical Society and started to use the SAGB in a controlled series of 50 procedures. During this time, laparoscopic surgery was not common and Dr. Hallberg and his assistant, Dr. Peter Forsell, started performing the open technique to implant the SAGB.

In 1992, Dr. Forsell was in contact with different surgeons in Switzerland, Italy and Germany who began to implant the SAGB with the laparoscopic technique. Dr. Forsell fully owned the patent at this time. In 1994, Dr. Forsell presented the SAGB at an international workshop for bariatric surgery in Sweden, and from then on, the SAGB started to be implanted laparoscopically. During this time, the SAGB was manufactured by a Swedish company, ATOS Medical.

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 45 kilograms or more over their estimated ideal weight according to the 1983 Metropolitan Life Insurance Tables or those between 35 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, some as young as 12.
• 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:

• If the surgery or treatment represents an unreasonable risk to the patient.
• Untreated endocrine diseases such as hypothyroidism.
• Inflammatory diseases of the gastrointestinal tract such as ulcers, esophagitis or Crohn’s disease.
• Severe cardiopulmonary diseases or other conditions which may make them poor surgical candidates in general.
• An allergic reaction to materials contained in the band or who have exhibited a pain intolerance to implanted devices.
• Dependency on alcohol or drugs.
• People with severe learning or cognitive disabilities or emotionally unstable people.

Benefits of gastric banding when compared to other bariatric surgeries


• Lower mortality rate: only 1 in 2000 versus 1 in 250 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)

Losing weight after surgery

Correct and sensitive adjustment of the band is imperative for weight loss and the long term success of the procedure. Adjustments (also called "fills") may be performed using an X-ray fluoroscope so that the radiologist may assess the placement of the band, the port and the tubing that runs between the port and the band. The patient is given a small cup of liquid that contains 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 down the esophagus 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 esophagus, 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 great a restriction and further investigation may be required. In some circumstances fluid is removed from the band prior to further investigation 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). For example, this is standard practice in the main bariatric surgery clinic in Melbourne, Australia, where AGB placement has been performed for more than ten years. Some UK services, such as Bristol, also do non-fluoroscopic adjustments. 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 one to two minutes..

For some patients this type of fill is not possible, due to issues such as partial rotation of the port, or excess tissue above the port making it difficult to determine its precise location. In these cases, 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 cc (ml) to 12 cc (ml) of fill fluid depending on the design. Band size is usually determined by personal preference of the surgeon who places the band together with what s/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, for example, 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 choose to place a small amount in the band at the time of surgery. The stomach tends to swell following surgery and it is possible that too great a restriction would be achieved if filled at that time. 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 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 this 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 and gastric bypass 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.

Effectiveness
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.[citation needed] This comes to roughly 22 to 45 kilograms the first year for most band patients. It is important to keep in mind that while most of the RNY patients drop the weight faster in the beginning, some studies have found that LAGB patients will have the same percentage of excess weight loss and comparable ability 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, in turn, helps in producing long term weight stability. However, with greater experience and longer patient follow up, multiple series are now being reported that have found suboptimal weight loss and high complication rates for the gastric band, particularly when used in younger patients.

A systematic review concluded "LAGB has been shown to produce a significant loss of excess weight while maintaining low rates of short-term complications and reducing obesity-related comorbidities. LAGB may not result in the most weight loss but it may be an option for bariatric patients who prefer or who are better suited to undergo less invasive and reversible surgery with lower perioperative complication rates. One caution with LAGB is the uncertainty about whether the low complication rate extends past three years, given a possibility of increased band-related complications (e.g., erosion, slippage) requiring re-operation".

The Royal College of Surgeons of England held a national consensus meeting on the status of bariatric surgery in the UK on 21 January 2010, in the course of which the President, John Black, drew attention to the inequality of access to WLS across the nation (in many strategic health authority areas the NICE thresholds for surgery are being ignored as bariatric service provision is geographically patchy and financial commitment is inadequate).

Single Site Laparoscopy (SSL) or Single Incision Laparoscopic Surgery (SILS)
Single Incision Laparoscopic Surgery or also referred to as Single Site Laparoscopy(SILS)(SSL) is an advanced, minimally invasive (keyhole) procedure in which the surgeon operates almost exclusively through a single entry point, typically the patient’s umbulicus (navel). Special articulating instruments and access ports obviate the need to place trochars externally for triangulation, thus allowing the creation of a small, solitary portal of entry into the abdomen. SILS has been used for several common surgical procedures including hernia repair , cholecystectomy [ and nephrectomy The SILS technique has also been used in weight-loss surgery for both sleeve gastrectomy and – more recently – for laparoscopic adjustable gastric banding (LAGB) .