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Adjustable gastric
banding is a form of
weight loss surgery (bariatrics) designed for obesity
patients with a body mass index (BMI) of 40 or greater. It
employs an inflatable silicone band which is implanted
around the top portion of a person’s stomach via
laparoscopic surgery. The implanted device creates a small
pouch at the top of the stomach which fills up quickly and
restricts the movement of the food into the bottom part of
the stomach. This restriction creates a feeling of fullness
which helps the person to eat less and therefore lose
weight. The band is adjustable via a subcutaneous access
port. A saline solution can be injected into the band via
this port to help to increase the feeling of restriction to
a point known as the “sweet spot” where optimal weight loss
can be reached. The ability to adjust the restriction makes
this a good choice for women who wish to become pregnant
after losing weight. The band can be unfilled to allow for
more food to be eaten as necessary for a healthy pregnancy.
The banding procedure, unlike
traditional gastric surgeries like Roux-en-Y gastric bypass
surgery (RNY), does not cut into or remove any part of the
digestive system. The procedure can be reversed simply by
removing the band, which can be done laparoscopically. With
the band there are also no malabsorption or dumping issues
since no intestines are removed or re-routed. All nutrients
are digested normally, so the rate of weight loss is
somewhat slower than RNY. On average, a “bandster” loses 1-2
pounds per week in the first year. This number can vary
widely depending on a person’s motivation and restriction
levels.
Disadvantages of the procedure include that the patient is
less likely to maintain weight loss over the long term when
compared to someone who has undergone Roux-en-Y gastric
bypass surgery or biliopancreatic diversion surgery. A
common risk of gastric banding include vomiting, which
occurs when the patient eats too much or the narrow passage
into the larger part of the stomach is blocked. Another is
slippage or wearing away of the band.
History of the procedure
and device
The first gastric band was
patented in 1985 by Obtech Medical of Sweden 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. Their LAP-BAND
System was introduced in Europe in 1993 and quickly became
more popular than the SAGB. The LAP-BAND System received FDA
approval for use in the United States in June 2001.
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:
If the obesity surgery or
obesity treatment represents an unreasonable risk to the
patient.
Glandular 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.
Mentally retarded or emotionally unstable people.
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)
Losing weight after surgery
Proper adjustment of the
band is very important to weight loss and the long term
success of the procedure. Adjustments (also called
"fills") are often done under
fluoroscope so that the doctor is able to see the
placement of the band, the port and the tubing which runs
between the port and the band. The patient is put under the
fluoroscope where he or she is given a small cup of a liquid
containing
barium. When swallowed, the drink shows up under the
fluoroscope and can be seen moving past the restriction
caused by the band. This allows the doctor to see the level
of restriction in the band and to access if there are any
problems - such as an enlarged pouch, prolapsed stomach
(when part of the stomach moves into the band where it does
not belong) or reflux caused by too much restriction. If any
of these problems is discovered the doctor will likely
remove all the saline from the band and have the patient
return in a few weeks for reevaluation. Most of the time
that is enough, but in a very small number of cases another
surgery could be required.
Some more experienced
doctors do their fills without the fluoroscope; 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. 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.
On average, it takes three
to five fills (where saline is inserted into the band via
the
subcutaneous port) for a person to reach the optimal
restriction for weight loss. The amount of saline needed in
the band varies from patient to patent. Some small number of
people find they do not need a fill at all and have
sufficient restriction right from the start, others may need
all the way up the maximum their band will hold. The bands
come in several sizes which can hold anywhere from 4 cm³ to
10 cm³ of saline. The size of the band used is determined by
the surgeon during surgery based on the size and thickness
of the patient's stomach.
The band is not filled at
surgery because the stomach tends to swell after the surgery
and filling it could cause total restriction, which is
undesirable.
The patient is usually put
on a liquid diet, followed by mushy foods and then solids.
They 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 is why a proper post-op diet and a good
after-care plan is critical to success. Most doctors make
the first adjustment at four to six weeks out from surgery
in order to give the stomach time to heal. After that fills
are performed as needed. Some doctors are 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 doctor if you are considering
this surgery. Recommendations can vary dramatically from
doctor to doctor and it is important to find a doctor with a
good post-surgical plan. Some doctors maintain support
groups, but unfortunately many of them mix RNY patients with
gastric banding patients. Some gastric band recipients 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
weigh lost 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.
Post-surgical diets
Gastric banding is intended
to make it easier to lose weight. However, success with this
procedure depends in large part on the diet and activities
of its recipients. The post-surgical diet varies greatly
depending on a person's surgeon, nutritionist, and personal
philosophy. To generalize, the common wisdom about the
post-surgical diet is one high in
protein and low in
carbohydrates - not dissimilar to an
Atkins diet plan or many other currently popular high
protein diets. The average diet contains 40 to 80 grams of
protein and roughly 1200 to 1500 calories (5,000 to 6,300
kJ) per day. Banders are encouraged to eat protein first,
then fruits and vegetables and only then starchy foods.
Someone who has had gastric
banding for some time can eat anywhere from 1/2 to 1 1/2
cups of food per meal. This amount can vary depending on the
softness of the food and the restriction of the person's
band. Many people find that they are more restricted in the
morning and that they loosen up over the course of the day.
Women tend to have fluctuations in their restriction levels
during their monthly cycle - often feeling particularly
restricted when they are menstruating.
Immediately following
surgery most patients are put on a liquid diet, although the
details can vary widely from doctor to doctor. Generally,
there are a couple of days of thin or clear liquids,
followed by two to four weeks of soft or puréed foods, and
then slowly the diet works up toward more solid foods.
When a patient reaches the
point of optimal restriction, they often have a few foods
that they find it best to avoid. Some people are unable to
eat fluffy
bread,
rice, or
pasta. Others have problems with
oranges (because of the skin on the sections),
grapes and other
fruits with skins. Still others may find that they are
unable to eat particular varieties of meat. In general,
patients are advised to start slow, chew thoroughly, and see
how they respond. There are no set rules for what you can
and cannot eat that fit everyone. Most vomiting incidents
with the newly banded happens due to insufficient chewing,
eating too big of a bite at once, or eating a couple bites
too many. As patients begin to understand the signals their
body is sending them for when to stop eating, they vomit a
good deal less.
The LAP-BAND in Australia
According to an August
2005 article in The Medical Journal of Australia , 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.
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