Gastric bands: How does a gastric band work?

Over the course of the last decade and more, the use of bariatric procedures such as gastric banding has gained acceptance and popularity as a surgical treatment for people who are obese.¹

Gastric banding is the second most common type of gastric surgery carried out in the US, next to gastric bypass surgery. Also known as laparoscopic or lap band surgery, gastric banding is designed to constrict the stomach so that a person feels fuller after eating less food than usual.

Figures from the American Society for Metabolic and Bariatric Surgery suggest that around 179,000 bariatric surgeries were performed in the US in 2013. Of these, 34.2% were Roux-en-Y gastric bypass, 14% gastric banding, 42.1% gastric sleeve, 1% as duodenal switch, 6% as revisional surgery and 2.7% classified as other.¹⁶

The estimated total cost of bariatric surgical procedures to the US health economy is estimated to be at least $1.5 billion each year.¹

This page offers more information about what gastric banding involves, who can benefit, what the risks and advantages are, and what other weight loss surgical procedures are available.

You will see introductions at the end of some sections to recent developments covered by MNT's news stories. Also look out for links to information about related conditions.

Contents of this article:

1. How does a gastric band work?
2. Gastric band surgery
3. Who is a suitable candidate for gastric banding?
4. Benefits of gastric banding
5. Disadvantages and risks of gastric banding
6. Other types of weight loss surgery, and robotics

Fast facts on gastric band surgery

Here are some key points about gastric band surgery. More detail and supporting information is in the body of this article.

• Gastric band surgery is a type of weight loss, or bariatric, surgery.
• It is a minimally invasive, quick, reversible and adjustable surgical procedure that decreases the size of the stomach to reduce food intake.
• The procedure involves the placement of an inflatable band around the top of the stomach. This band is filled with saline to constrict the stomach so a person feels fuller with less food.
• The operation is usually done as a short day-procedure under general anesthetic via small incisions in the abdomen, with the surgeon guided by laparoscope (keyhole surgery).
• Patients must adhere to a strict liquids-only diet with gradual reintroduction of soft foods for up to six weeks following the surgery.
• Banding can result in significant weight loss (almost 50% of excess weight within 3 years) and improve diabetes, although weight loss varies greatly.
• Gastric banding has a lower risk of serious complications than gastric bypass and is the only 100% reversible weight-loss procedure.
• Risks include those involved with any general surgery as well as complications specific to the procedure, such as potential slippage of the band.
• Gastric banding is associated with more minor complications than other bariatric surgeries, including a much higher rate of reoperation.

How does a gastric band work?

Gastric banding is a type of weight loss (bariatric) surgery that involves placing a silicone band around the upper part of the stomach to decrease stomach size and reduce food intake.^2-4 It was approved for use as a weight-loss treatment by the US Food and Drug Administration (FDA) in 2001.⁵

The gastric band is put in place around the upper portion of the stomach and the tube attached to the band is accessible via a port under the skin of abdomen. The surgeon uses this port to inject saline solution into the band to inflate it, with adjustments made to alter the degree of constriction around the stomach. The band creates a small stomach pouch above it, with the rest of the stomach below.^2-4,6

Weight loss surgery targets the gut, the stomach in particular.

The smaller stomach pouch reduces the amount of food that can be held in the stomach at any one time. The result is an increased feeling of fullness after eating a smaller amount of food, which, in turn, reduces hunger and helps a person to lower their overall food intake. The exact way in which it works is not clear.^2-4

One major advantage of this form of bariatric procedure is that it does not create any malabsorption - all food consumed is digested and absorbed normally.^2-4

Other names for the procedure are Lap-Band (the name of the commercial device), laparoscopic adjustable gastric banding (LAGB), bariatric surgery, laparoscopic gastric banding and, simply, the band.

Gastric band surgery

A gastric band is fitted under general anesthesia, usually in an outpatient clinic as a day procedure, with patients typically able to go home later the same day.^2,4

The procedure is minimally invasive and is performed through keyhole incisions - one to five small surgical cuts in the abdomen - using a laparoscope with a camera.^2,4

Experienced surgeons are usually able to complete the procedure in 30 minutes to an hour.^2,4

Because of the general anesthesia, patients should not eat on the day of the surgery (from midnight the night before). Most people undergoing it have a week off work and can resume most normal activities within a day or two.^2,4

For the first 2-3 weeks after the procedure, diet is restricted to liquids and liquidized foods, after which soft foods are introduced until diet is along a normal regime after around 6 weeks.^2,4

Who is a suitable candidate for gastric banding?

Eligibility for a gastric band placement is restricted to people who are severely obese, with a body-mass index (BMI) of 40 or over.

Only people who are severely obese - with a BMI of 40 or more - are eligible for weight loss surgery.

A smaller person may be eligible if there are other obesity-related problems such as diabetes, hypertension or sleep apnea.^7,8

Other treatment options for obesity need to have been exhausted before surgery is considered - patients must first try lifestyle changes to diet and activity, and medications.^7,8

Some research suggests that there is a benefit to performing bariatric surgery sooner rather than later in people who are obese and who have type 2 diabetes. Earlier intervention has been recommended in people with pre-diabetes or with a high risk of developing diabetes.⁹

Some people are not considered candidates for weight loss surgery, with contraindications including:⁸

• Current drug or alcohol abuse
• Uncontrolled psychiatric illness
• Inability to understand the risks and benefits, outcomes, alternatives, and lifestyle changes demanded.

Benefits of gastric banding

A review of studies including all types of weight loss surgeries, not just gastric banding, found that, on average, patients lost 38.5 kilograms or 55.9% of excess body weight and that 78.1% of patients with diabetes had complete resolution of the condition. However, people achieved the greatest amount of weight loss and diabetes resolution following a duodenal switch surgery, with gastric bypass the second most successful and gastric banding the least successful in this regard.¹⁰

However, a retrospective analysis of 120 morbidly obese patients undergoing gastric banding between 2003 and 2007 found a high rate of failure for the procedure over almost five years. In fact, the results led the authors to suggest that gastric banding "should be abandoned as a primary bariatric procedure for the majority of morbidly obese patients because of its high failure rate."¹⁷

Among the 120 patients, 16 had the band removed, either because of unmanageable symptoms or because they had an alternative bariatric procedure performed. The patients who experienced success with the gastric band had an average loss of 44.9% excess weight. However, more than a third (35.6%) of patients had less than 20% excess weight loss and 44% of patients had band failure.

Another review, published in 2014 in the journal Surgery for Obesity and Related Disease, came to the same conclusion. These researchers found that 53% of patients had their gastric band removed due to insufficient weight loss or complications or converted to a gastric bypass procedure over the following 14 years. The review looked at 201 patients undergoing laparoscopic gastric banding for morbid obesity in a specialized Dutch center between 1995 and 2003.¹⁸

Two thirds of patients did achieve an excess weight loss of more than 50% at some point after their surgery, but half of the remaining patients had negligible weight loss. Less than a quarter (22%) of all patients had a functioning band and a good result after the 14 year follow-up.

In addition, the comorbidities that initially improved after gastric banding tended to return, and patients also developed new comborbidities. Complications were experienced by almost half (47%) of patients, and 68% of patients had reoperations.

Having a gastric band fitted is not a guarantee of weight loss or resolution of diabetes, sleep apnea or other comorbidities, but some patients do experience significant benefits.

In one review, patients with type 2 diabetes who underwent gastric banding had an almost sevenfold increased chance of remission of their diabetes compared with matched control patients. Those who underwent gastric bypass had a 43-fold increased chance of remission, and those undergoing a sleeve gastrectomy had almost a 17-fold increased chance of remission.¹⁹

The advantages of gastric banding include:^{1-4,6,9,11,12}

• The potential for substantial, long-term weight loss for obese individuals - nonsurgical treatments in the morbidly obese are rarely successful in the long term
• Fewer side effects than many pharmaceutical alternatives
• The potential to significantly improve diabetes and prediabetes
• The potential benefits of major weight loss for anyone who is obese, such as increased mobility and capability for daily activities, decreased risk of numerous chronic disease, improvements in asthma, gastroesophageal reflux disease (GERD), high blood pressure, high cholesterol and obstructive sleep apnea
• Reversibility (the band can be removed) and adjustability (it can be tightened or loosened in response to problems eating, if not enough weight is being lost, or there is vomiting after eating)
• No need to cut the stomach or reroute the intestines, meaning that normal digestive processes are unaffected and malabsorption issues are less likely
• Needing only a short time in hospital - usually less than 24 hours - and often with same-day discharge
• A lower number of complications after surgery and the lowest risk for vitamin or mineral deficiencies among weight loss surgical options
• Fewer postsurgical demands in terms of dietary recommendations, vitamin and mineral supplementation, and follow-up care, compared with other bariatric operations
• Fewer complications, such as wound infections and postoperative hernias, compared with open surgery (although open surgery is rarely done, accounting for just 3% of bariatric procedures)
• The potential for improvements in psychiatric symptoms among severely obese adolescents (compared to lifestyle and dietary interventions)
• Employment benefits, such as greater worker productivity, and faster recovery after laparoscopic surgery.

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On the next page, we look at disadvantages and risks of gastric banding, and other types of weight loss surgery.

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