Gastric Banding

Gastric banding is a restrictive type of surgery in which a silicone band is placed around the top portion of the stomach. The band generates a small pouch with limited volume which will provide an early and prolonged feeling of satiety; additionally, the band slows the passage of food from the pouch to the lower part of the stomach, thus leading to decreased food intake and subsequent weight loss. ^{[1, 2]} This procedure is most commonly done using the laparoscopic minimally invasive approach.

A single-surgeon study by Furbetta et al found a mean excess weight loss of 49%, 52.6%, and 59.2% at 10-, 15-, and 20-year follow-up, respectively, after laparoscopic adjustable gastric banding. ^[3]

A report by Hutter et al found that laparoscopic adjustable gastric banding has lower risk-adjusted morbidity, readmission, and reoperation/intervention rates than laparoscopic sleeve gastrectomy, laparoscopic Roux-en-Y gastric bypass, and open Roux-en-Y gastric bypass. ^[4]

A study by Shimada et al, however, indicated that in obese adults with cardiovascular disease, the rate of emergency department visits or unplanned hospitalizations (ie, acute care use) is lower in those who undergo gastric bypass than in patients treated with gastric banding, over the first 2 postoperative years. For example, the adjusted rate ratio in the study for the first 7-12 months was 0.77, dropping further over time. ^[5]

Procedure Background

Before gastric banding is discussed, some background information will be reviewed.

Body fat estimation

Obesity is defined as excess accumulation of body fat that may impair health. A simple and practical, albeit imperfect, method to estimate body fat percentage is the body mass index (BMI). BMI is calculated from an individual's height (in meters [m]) and weight (in kilograms [kg]) as follows: BMI = kg/m². BMI has its drawbacks, as it does not account for body fat percentage, and it may overestimate or underestimate body fat composition in certain individuals.

Visceral fat (central obesity) has a much stronger correlation with metabolic and cardiovascular diseases. The absolute waist circumference (> 102 cm in men and > 88 cm in women) or waist-hip ratio (> 0.9 for men and > 0.85 for women) are both used as measures of central obesity.

However, BMI has become a standard method of evaluating height to weight ratio in most individuals, and thus, this calculation has become an indicator of obesity. Thus, BMI is classified as follows:

• BMI less than 18.5 kg/m²: Underweight

• BMI of 18-24.9 kg/m²: Normal weight

• BMI of 25-29.9 kg/m²: Overweight

• BMI of 30 kg/m² or greater: Obese

Obesity, in turn, can be subclassified into 3 categories, as follows:

• Class I: BMI 30-34.9 kg/m²

• Class II: BMI 35-39.9 kg/m²

• Class III: BMI ≥ 40kg/m²

Global epidemic

According to the World Health Organization, worldwide obesity is nearly three times greater than it was in 1975, with figures for 2016 including over 1.9 billion overweight adults (aged 18 y or older) and, within this population, over 650 million obese individuals (39% and 13% of adults around the world, respectively). ^[6]  Between 2015 and 2016, 39.8% of US adults aged 20 or older were obese, including 42.8% of those aged 49-59 years. ^[7]

The morbidity associated with obesity is alarming, with an increased incidence of metabolic syndrome, type 2 diabetes mellitus, hypertension, and dyslipidemia, among many other comorbidities.

Intervention

The need for safe, efficient, and effective means through which patients are able to lose weight and subsequently maintain an adequate body fat percentage is imperative. In this regard strategies aimed at improving healthy eating habits, exercise, and behavioral modification have been only moderately effective in aiding with moderate weight loss. Nonoperative weight loss therapies have not induced long-term weight loss or a sustainable reduction in comorbidities. ^[8]

Surgery has proved to be safe and, so far, is the only method available that can induce and maintain major weight loss. ^{[1, 9, 10, 11, 12]} One such procedure for weight loss is gastric banding, an example of which can be seen in the video below. ^{[13, 14]}

Lap-Band and Realize Adjustable Gastric Band

There are 2 types of adjustable gastric bands approved by the US Food and Drug Administration (FDA), Lap-Band and Realize Band. ^[15] The Lap-Band System obtained FDA approval in 2001, of which the latest models are the Lap-Band AP-L and Lap-Band AP-S. These bands have fill volumes of 14 mL and 10 mL, respectively.

The Realize Adjustable Gastric Band obtained FDA approval in 2007; its 2 models are the Realize Band and the newer Realize Band-C. The maximum fill volume for the Realize Band is 9 mL, whereas that for the Realize Band-C is smaller. Both the Realize Bands are "one-size-fits-all"; however, the Realize Band-C has a 14% greater adjustment range than the Realize Band. The Realize Adjustable Gastric Band differentiates itself from the Lap-Band AP series through its sutureless, injection port installation.

Other adjustable gastric bands

Two other adjustable gastric bands are in use outside of the United States, neither of which has FDA approval: Heliogast and Midband. The Midband was the first to market in 2000, and the Heliogast band followed in 2003.

Indications and Contraindications

Indications for laparoscopic adjustable gastric banding (LAGB) include the following:

• Individuals with a body mass index (BMI) greater than 40 kg/m²

• Individuals with a BMI between 30 and 40 and who have at least one comorbidity that is associated with obesity

In February 2011, The FDA expanded approval of the Lap-Band system to patients with a BMI between 30 to 40 kg/m² and one weight-related comorbidity. ^[15] Additionally, patients should have attempted, without success, to lose an appropriate amount of weight through supervised dietary changes.

Contraindications to LAGB include the following:

• Inflammatory diseases of the gastrointestinal tract (eg, Crohn disease, severe esophagitis)

• Cirrhosis, portal hypertension, esophageal or gastric varices

• Previous gastric perforation near the site of band placement or gastrostomy

• Congenital anomalies of the digestive tract (ie, esophagus, stomach, duodenum, situs inversus, etc)

• Severe heart or lung disease

• Any condition/disease that presents a contraindication for general anesthesia

• Autoimmune connective tissue diseases (eg, systemic lupus erythematosus, scleroderma)

• Chronic use of steroids or other immunosuppressant medications

• Chronic pancreatitis

Operative Equipment

Variations in port placement and positioning should be considered and tailored to the individual surgeon's experience.

Operative equipment used include the following:

• One 10-mm trocar

• One 15-mm trocar

• Three 5-mm trocars

• Thirty-degree (30°) scope

• Laparoscopic liver retractor

• External fixation device for retractor

• Laparoscopic grasping forceps

• Laparoscopic atraumatic grasping forceps

• Laparoscopic cautery hook

• Laparoscopic needle holder

• Laparoscopic scissors

• Articulating dissector

Patient Preparation

Anesthesia and patient positioning are briefly described below.

Anesthesia

Laparoscopic adjustable gastric banding is carried out under general anesthesia, with an intubated patient. Patients should have a liquid diet 24 hours before surgery and a minimum of 12 hours of nothing by mouth (NPO) before surgery.

Venous compression boots are applied and all pressure points are padded. The patient is then given prophylactic antibiotic and unfractionated heparin, 5000 international units (IU) subcutaneously (SC), or low–molecular-weight heparin (LMWH) should be initiated within 30 to 120 minutes before surgery. General anesthesia is induced.

Positioning

The patient is placed on the operating table in the supine position with both arms out or in the lithotomy position, depending on the surgeon’s preference. The patient is secured to the operating table to prevent sliding.

The patient’s abdomen is prepped with 2% chlorhexidine gluconate/70% isopropyl alcohol solution and draped. The surgeon is positioned to the right side or between the patient’s legs (if lithotomy position), and the first assistant is on the patient’s left side. The balloon of the band should be checked before placing it to detect any leak in the system.

Monitoring and Follow-Up

The laparoscopic adjustable gastric banding (LAGB) procedure allows for a 1 night hospital stay if not outpatient treatment.

Band adjustment

After band placement, the patient will return for follow-up band adjustment after 4 to 6 weeks. Adjustment is carried out by inflating the band with saline solution through the subdermal access port. A noncoring (Huber) needle should be the only type of needle used.

The band will be adjusted in order to generate an opening small enough that will allow both liquids and solids to go through, but it will impede the passage of large amounts of food. The first fill consists of 3 mL in a male patient and 4 mL in a female patient.

The second adjustment occurs at the postoperative week 8, adding 0.5 to 1 mL fill. Further fills occur at 1- to 2-month intervals in the 0.2 to 0.6 mL range, depending on the subjective degree of restriction that the patient feels.

Patient education

Educating the patient regarding how much to eat, what type of foods to eat, as well as adequate exercise routines are keys in helping the patient lose weight and achieve an adequate quality of life. ^{[11, 16, 17]}

Approach Considerations

The initial placement technique of the laparoscopic adjustable gastric band (LAGB) was a perigastric one. However, this approach has been implicated in high rates of band prolapse/slippage being reported. ^{[18, 19]}

The currently favored approach is referred to as the pars flaccida technique.

Pars Flaccida Technique

The pars flaccida procedure is laparoscopic and is normally carried out using a 4- or 5-port technique. A long Verres needle or a 5-mm optical trocar is introduced in the abdomen just below the costal margin in the left upper quadrant at the midclavicular line, and the abdomen is insufflated. If a Verres needle was used, a 5-mm trocar is placed. The patient is tilted into steep reverse Trendelenburg position.

Placement of trocars

After the left costal margin–midclavicular line trocar is placed, 4 more trocars will be placed under direct vision in the following order:

1. A 15-mm trocar 6 fingerbreadths below the xiphoid and 5 cm left of the midline for a 30° optical system; it becomes the site of the access port at completion

2. A 5-mm port is placed in the right upper abdomen approximately mirroring the one on the left

3. Depending on the liver retractor, a 5-mm trocar is placed in the right anterior axillary line for a Snowden-Pencer Brand Diamond-Flex retractor, or it is placed in the midline just below the sternum for a Nathanson liver retractor to hold the left lobe of the liver

4. If the surgeon stands between the patient's legs, a port is placed lateral and below the port in the left upper abdomen; if the surgeon is positioned to the right of the patient, a 10-mm port is placed between the right upper abdomen trocar and the 15-mm trocar

Dissection

The dissection begins at the angle of His with release of the gastrophrenic attachments. Subsequently, a window is created in the pars flaccida of the gastrohepatic ligament.

Where the crus meets the retroperitoneal fat, a small opening is made, and dissection at the right crus is performed to create a retrogastric tunnel.

An Endo-Grasp Roticulator or an articulating dissector is passed gently into the retrogastric tunnel under direct vision. The instrument is then curved, and its tip is visualized in the dissection area of the gastrophrenic attachments.

Band introduction

The band is passed through the 15 mm port into the abdomen. This technique is different depending on the band used: (1) The Realize Adjustable Gastric Band is passed through the posterior tunnel by hooking a preattached Ethibond suture onto the endoscopic dissector or (2) for the Lap-Band, the end of the tubing is passed behind the stomach, and the band is locked in placed upon itself. The band is to be oriented with the balloon facing the stomach wall. ^[18]

The fundus of the stomach is then imbricated over the band with 3 gastrogastric nonabsorbable sutures.

Exteriorization of tubing

The tubing is exteriorized using the 15-mm trocar and connected to a port. The band's injection port requires an approximately 3 × 3-cm area of anterior rectus muscle fascia to be cleared off. The balloon of the band must be totally evacuated of all air once the system of the tubing and port are intact. For the Realize Band, the injection port is connected to the port applier, and the unit is applied against the fascia and fired using the trigger. For the Lap-Band, the port is fixed with 4 stitches to the abdominal fascia.

Closing

The liver retractor and the trocars are removed, and incisions are closed in standard fashion.

Video example

The following is a video demonstrating LAGB using the Realize Band.

Procedure Complications

The total complication rate for laparoscopic adjustable gastric band (LAGB) procedures has been estimated at 11%. Specific complications and their frequency include the following:

• Mortality rate: 0.05%

• Access port problems: 0.11-3.0%

• Band erosion: 0.2-2% ^[20]

• Band slippage: 3.1-8.1%

• Esophageal dilatation: 6.6-10%

A study by Khoraki et al, however, reported a high failure rate associated with laparoscopic gastric banding, finding that the procedure failed in 118 out of 208 patients (57%). The investigators determined that only higher baseline BMI was independently linked to failure. ^[21]

Band slippage is classified into 5 types according to O’Brien and Dixon ^{[19, 22, 23]} and are summarized in Table 1, below. ^[23]

Table 1. Band Slippage Classification (Open Table in a new window)

A retrospective study by Wise et al indicated that African American race and preoperative diabetes mellitus are independent risk factors for impairment of excess weight loss in patients over age 50 years who undergo LAGB. The study involved 117 patients over age 50 years who were treated with LAGB, with multivariate linear regression analysis finding that diabetes mellitus and African American race were independent risk factors for impaired excess weight loss at 6 months following surgery. However, only diabetes mellitus was a risk factor at 1 year postoperatively. ^[24]

A study by Fournier et al indicated that when LAGB fails, laparoscopic conversion of patients to a Roux-en-Y gastric bypass is feasible and effective. The revision surgery led to weight-loss results over a 10-year follow-up period that were comparable to those for primary Roux-en-Y procedures. The study, which involved 642 patients, also found that the complication rate did not differ between 1- and 2-step bypass operations. ^[25]