Adjustable gastric band
A laparoscopic adjustable gastric band, commonly called a lap-band, A band, or LAGB, is an inflatable silicone device placed around the top portion of the stomach to treat obesity, intended to decrease food consumption.
Adjustable gastric band surgery is an example of bariatric surgery designed for obese patients with a body mass index of 40 or greater—or between 35 and 40 in cases of patients with certain comorbidities that are known to improve with weight loss, such as sleep apnea, diabetes, osteoarthritis, GERD, hypertension, or metabolic syndrome, among others.
In February 2011, the United States Food and Drug Administration expanded approval of adjustable gastric bands to patients with a BMI between 30 and 40 and one weight-related medical condition, such as diabetes or high blood pressure. However, an adjustable gastric band may be used only after other methods such as diet and exercise have been tried.
Working principle
The inflatable band is placed around the upper part of the stomach to create a smaller stomach pouch. This slows and limits the amount of food that can be consumed at one time, thus giving the opportunity for the sense of satiety to be met with the release of peptide YY. It does not decrease gastric emptying time. The individual achieves sustained weight loss by choosing healthy food options, limiting food intake and volume, reducing appetite, and progress of food from the top portion of the stomach to the lower portion digestion.According to the American Society for Metabolic Bariatric Surgery, bariatric surgery is not an easy option for obesity sufferers. It is a drastic step, and carries the usual pain and risks of any major gastrointestinal surgical operation. However, gastric banding is the least invasive surgery of its kind and is completely reversible, with another "keyhole" operation. Gastric banding is performed using laparoscopic surgery and usually results in a shorter hospital stay, faster recovery, smaller scars, and less pain than open surgical procedures. Because no part of the stomach is stapled or removed, and the patient's intestines are not re-routed, they can continue to absorb nutrients from food normally. Gastric bands are made entirely of biocompatible materials, so they are able to stay in the patient's body without causing harm.
However, not all patients are suitable for laparoscopy. Patients who are extremely obese, who have had previous abdominal surgery, or have complicating medical problems may require the open approach.
Placement via laparoscopic surgery
The surgical insertion of an adjustable gastric band is often referred to as a lap band procedure or band placement. First, a small incision is made near the belly button. Carbon dioxide is introduced into the abdomen to create a work space for the surgeon. Then a small laparoscopic camera is placed through the incision into the abdomen. The camera sends a picture of the stomach and abdominal cavity to a video monitor. It gives the surgeon a good view of the key structures in the abdominal cavity. A few additional small incisions are made in the abdomen. The surgeon watches the video monitor and works through these small incisions using instruments with long handles to complete the procedure. The surgeon creates a small, circular tunnel behind the stomach, inserts the gastric band through the tunnel, and locks the band around the stomach.Clinical studies of laparoscopic bariatric surgery patients found that they felt better, spent more time doing recreational and physical activities, benefited from enhanced productivity and economic opportunities, and had more self-confidence than they did prior to surgery.
Mechanics
The placement of the band creates a small pouch at the top of the stomach. This pouch holds approximately of food, whereas the typical stomach holds about of food. The 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, feel full more quickly and for a longer period of time, eat smaller portions, and lose weight over time.As patients lose weight, their bands will need adjustments, or "fills", to ensure comfort and effectiveness. The gastric band is adjusted by introducing a saline solution into a small access port placed just under the skin. A specialized non-coring needle is used to avoid damage to the port membrane and prevent leakage. There are many port designs, and they may be placed in varying positions based on the surgeon's preference, but are always attached to the muscle wall in and around the diaphragm.
Adjustable gastric bands hold between 4 and 12 cc of saline solution, depending on their design. When the band is inflated with saline solution, it places pressure around the outside of the stomach. This decreases the size of the passage between the pouch created from the upper part of the stomach and the lower stomach and further restricts the movement of food. Over the course of several visits to the doctor, the band is filled until the optimal restriction has been achieved – neither so loose that hunger is not controlled, nor so tight that food cannot move through the digestive system. The number of adjustments required is an individual experience and cannot be accurately predicted.
Types of adjustable bands
In the U.S. market, one adjustable gastric band is currently approved by the FDA: Lap-Band. The Lap-Band System obtained FDA approval in 2001. The Realize Band lost FDA approval in 2016. 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.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 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 entered the market in 2003. The device features a streamlined band to ease insertion during the operation.
Surgical 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 or more over their estimated ideal weight, according to the National Institutes of Health, or those with a BMI between 30 and 40 with co-morbidities that may improve with weight loss
- Age between 18 and 55 years.
- Failure of medically supervised dietary therapy.
- History of obesity.
- Comprehension of the risks and benefits of the procedure and willingness to comply with the substantial lifelong dietary restrictions required for long-term success.
- 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.
Special considerations for pregnancy
It is highly advised to take extra precautions during intercourse after surgery, as rapid weight loss increases fertility. Effective birth control methods must be used at all times to avoid unwanted pregnancies. Two factors have been pointed out by experts that may help explain this increase in fertility: reversal of PCOS and reduction in the excess of estrogen, which is produced by fat cells.
Comparison with other bariatric surgeries
Unlike more open forms of weight loss surgery, Biliopancreatic diversion and Duodenal Switch ), gastric banding does not require cutting or removing any part of the digestive system. It is removable, requiring only a laparoscopic procedure to remove the band, after which the stomach usually returns to its normal pre-banded size so it is not unusual for a person to gain weight after having a band removed. However, it is not entirely reversible as adhesions and tissue scarring are inevitable. 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 routinely required following gastric banding. Gastric dumping syndrome issues also do not occur since intestines are not removed or re-routed.Typically, patients who undergo adjustable gastric banding procedures lose less weight over the first 3.5 years than those who have RNY gastric bypass, BPD, or DS surgeries. Although other procedures appear to result in greater weight loss than adjustable gastric banding in the short term, results from the study by Maggard suggest that this difference decreases significantly over time. Gastric banding patients lose an average of 47.5% of their excess weight, according to a meta analysis by Buchwald.
It is important to note that, in order to maintain their weight reduction, patients must carefully follow post-operative guidelines relating to diet, exercise, and band maintenance. Weight regain is possible with any weight loss procedure, including the more radical procedures that initially result in rapid weight loss. The National Institutes of Health recommendation for weight loss is 1 to 2 pounds per week, and an average banded patient may lose this amount. This is variable based on the individual and their personal circumstances, motivation, and mobility.