Weight
Loss Surgery Options
The American Society for Bariatric Surgery describes two basic approaches that
weight loss surgery takes to achieve change: - Restrictive
procedures that decrease food intake.
- Malabsorptive
procedures that alter digestion, thus causing the food to be poorly digested and
incompletely absorbed so that it is eliminated in the stool.
Vertical Banded Gastroplasty (VBG) is a purely restrictive procedure. In this
procedure the upper stomach near the esophagus is stapled vertically for about
2-1/2 inches (6 cm) to create a smaller stomach pouch. The outlet from the pouch
is restricted by a band or ring that slows the emptying of the food and thus creates
the feeling of fullness. 
Advantages
- The primary
advantage of this restrictive procedure is that a reduced amount of well-chewed
food enters and passes through the digestive tract in the usual order. That allows
the nutrients and vitamins (as well as the calories) to be fully absorbed into
the body.
- After
10 years, studies show that patients can maintain 50% of targeted excess weight
loss.
Risks
- Postoperatively,
stapling of the stomach carries with it the risk of staple-line disruption that
can result in leakage and/or serious infection. This may require prolonged hospitalization
with antibiotic treatment and/or additional operations.
- Staple-line
disruption may also, in the long-term, lead to weight gain. For these reasons,
some surgeons divide the staple-line wall of the pouch from the rest of the stomach
to reduce the risk of long-term staple-line disruption.
- The
band or ring applied may lead to complications of obstruction or perforation,
requiring surgical intervention.
- Characteristically,
these procedures, while creating a sense of fullness, do not provide the necessary
feeling of satisfaction that one has had "enough" to eat.
- Because
restrictive procedures rely solely on a small stomach pouch to reduce food intake,
there is the risk of the pouch stretching or of the restricting band or ring at
the pouch outlet breaking or migrating, thus allowing patients to eat too much.
- Around
40% of patients undergoing these procedures have lost less than half their excess
body weight.
- As
is the case with all weight loss surgeries, readmission to a hospital may be required
for fluid replacement or nutritional support if there is excessive vomiting and
adequate food intake cannot be maintained.
While these operations also reduce the size of the stomach, the stomach pouch
created is much larger than with other procedures. The goal is to restrict the
amount of food consumed and alter the normal digestive process, but to a much
greater degree. The anatomy of the small intestine is changed to divert the bile
and pancreatic juices so they meet the ingested food closer to the middle or the
end of the small intestine.With the three approaches discussed below, absorption
of nutrients and calories is also reduced, but to a much greater degree than with
previously discussed procedures. Each of the three differs in how and when the
digestive juices (i.e., bile) come into contact with the food. Since
food bypasses the duodenum, all the risk considerations discussed in the gastric
bypass section regarding the malabsorption of some minerals and vitamins also
apply to these techniques, only to a greater degree.  Biliopancreatic
Diversion (BPD)
BPD removes approximately
3/4 of the stomach to produce both restriction of food intake and reduction of
acid output. Leaving enough upper stomach is important to maintain proper nutrition.
The small intestine is then divided with one end attached to the stomach pouch
to create what is called an "alimentary limb." All the food moves through this
segment, however, not much is absorbed. The bile and pancreatic juices move through
the "biliopancreatic limb," which is connected to the side of the intestine close
to the end. This supplies digestive juices in the section of the intestine now
called the "common limb." The surgeon is able to vary the length of the common
limb to regulate the amount of absorption of protein, fat and fat-soluble vitamins.
 Extended
(Distal) Roux-en-Y Gastric Bypass (RYGBP-E)
RYGBP-E is an alternative means of achieving malabsorption by creating a stapled
or divided small gastric pouch, leaving the remainder of stomach in place. A long
limb of the small intestine is attached to the stomach to divert the bile and
pancreatic juices. This procedure carries with it fewer operative risks by avoiding
removal of the lower 3/4 of the stomach. Gastric pouch size and the length of
the bypassed intestine determine the risks for ulcers, malnutrition and other
effects.  Biliopancreatic
Diversion with "Duodenal Switch"
This procedure
is a variation of BPD in which stomach removal is restricted to the outer margin,
leaving a sleeve of stomach with the pylorus and the beginning of the duodenum
at its end. The duodenum, the first portion of the small intestine, is divided
so that pancreatic and bile drainage is bypassed. The near end of the "alimentary
limb" is then attached to the beginning of the duodenum, while the "common limb"
is created in the same way as described above. Advantages
- These
operations often result in a high degree of patient satisfaction because patients
are able to eat larger meals than with a purely restrictive or standard Roux-en-Y
gastric bypass procedure.
- These
procedures can produce the greatest excess weight loss because they provide the
highest levels of malabsorption.
- In
one study of 125 patients, excess weight loss of 74% at one year, 78% at two years,
81% at three years, 84% at four years, and 91% at five years was achieved.
- Long-term
maintenance of excess body weight loss can be successful if the patient adapts
and adheres to a straightforward dietary, supplement, exercise and behavioral
regimen.
For
all malabsorption procedures there is a period of intestinal adaptation when bowel
movements can be very liquid and frequent. This condition may lessen over time,
but may be a permanent lifelong occurrence. Abdominal
bloating and malodorous stool or gas may occur. - Close
lifelong monitoring for protein malnutrition, anemia and bone disease is recommended.
As well, lifelong vitamin supplementing is required. It has been generally observed
that if eating and vitamin supplement instructions are not rigorously followed,
at least 25% of patients will develop problems that require treatment.
- Changes
to the intestinal structure can result in the increased risk of gallstone formation
and the need for removal of the gallbladder.
- Re-routing
of bile, pancreatic and other digestive juices beyond the stomach can cause intestinal
irritation and ulcers.
In recent years, better clinical understanding
of procedures combining restrictive and malabsorptive approaches has increased
the choices of effective weight loss surgery for thousands of patients. By adding
malabsorption, food is delayed in mixing with bile and pancreatic juices that
aid in the absorption of nutrients. The result is an early sense of fullness,
combined with a sense of satisfaction that reduces the desire to eat.
 According
to the American Society for Bariatric Surgery and the National Institutes of Health,
Roux-en-Y gastric bypass is the current gold standard procedure for weight loss
surgery. It is one of the most frequently performed weight loss procedures in
the United States. In this procedure, stapling creates a small (15 to 20cc) stomach
pouch. The remainder of the stomach is not removed, but is completely stapled
shut and divided from the stomach pouch. The outlet from this newly formed pouch
empties directly into the lower portion of the jejunum, thus bypassing calorie
absorption. This is done by dividing the small intestine just beyond the duodenum
for the purpose of bringing it up and constructing a connection with the newly
formed stomach pouch. The other end is connected into the side of the Roux limb
of the intestine creating the "Y" shape that gives the technique its name. The
length of either segment of the intestine can be increased to produce lower or
higher levels of malabsorption. Advantages
The
average excess weight loss after the Roux-en-Y procedure is generally higher in
a compliant patient than with purely restrictive procedures. One
year after surgery, weight loss can average 77% of excess body weight. Studies
show that after 10 to 14 years, 50-60% of excess body weight loss has been maintained
by some patients. A
2000 study of 500 patients showed that 96% of certain associated health conditions
studied (back pain, sleep apnea, high blood pressure, diabetes and depression)
were improved or resolved. Risks
Because
the duodenum is bypassed, poor absorption of iron and calcium can result in the
lowering of total body iron and a predisposition to iron deficiency anemia. This
is a particular concern for patients who experience chronic blood loss during
excessive menstrual flow or bleeding hemorrhoids. Women, already at risk for osteoporosis
that can occur after menopause, should be aware of the potential for heightened
bone calcium loss. Bypassing
the duodenum has caused metabolic bone disease in some patients, resulting in
bone pain, loss of height, humped back and fractures of the ribs and hip bones.
All of the deficiencies mentioned above, however, can be managed through proper
diet and vitamin supplements. A
chronic anemia due to Vitamin B12 deficiency may occur. The problem can usually
be managed with Vitamin B12 pills or injections. A
condition known as "dumping syndrome " can occur as the result of rapid emptying
of stomach contents into the small intestine. This is sometimes triggered when
too much sugar or large amounts of food are consumed. While generally not considered
to be a serious risk to your health, the results can be extremely unpleasant and
can include nausea, weakness, sweating, faintness and, on occasion, diarrhea after
eating. Some patients are unable to eat any form of sweets after surgery. In
some cases, the effectiveness of the procedure may be reduced if the stomach pouch
is stretched and/or if it is initially left larger than 15-30cc. The
bypassed portion of the stomach, duodenum and segments of the small intestine
cannot be easily visualized using X-ray or endoscopy if problems such as ulcers,
bleeding or malignancy should occur.
For the
last decade, laparoscopic procedures have been used in a variety of general surgeries.
Many people mistakenly believe that these techniques are still "experimental."
In fact, laparoscopy has become the predominant technique in some areas of surgery
and has been used for weight loss surgery for several years. Although few bariatric
surgeons perform laparoscopic weight loss surgeries, more are offering patients
this less invasive surgical option whenever possible. When
a laparoscopic operation is performed, a small video camera is inserted into the
abdomen. The surgeon views the procedure on a separate video monitor. Most laparoscopic
surgeons believe this gives them better visualization and access to key anatomical
structures.
 The
camera and surgical instruments are inserted through small incisions made in the
abdominal wall. This approach is considered less invasive because it replaces
the need for one long incision to open the abdomen. A recent study shows that
patients having had laparoscopic weight loss surgery experience less pain after
surgery resulting in easier breathing and lung function and higher overall oxygen
levels. Other realized benefits with laparoscopy have been fewer wound complications
such as infection or hernia, and patients returning more quickly to pre-surgical
levels of activity.
 Laparoscopic
procedures for weight loss surgery employ the same principles as their "open"
counterparts and produce similar excess weight loss. Not all patients are candidates
for this approach, just as all bariatric surgeons are not trained in the advanced
techniques required to perform this less invasive method. The American Society
for Bariatric Surgery recommends that laparoscopic weight loss surgery should
only be performed by surgeons who are experienced in both laparoscopic and open
bariatric procedures.
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