General
Stats:
- Description: A long,
flexible tube with a camera mounted on the end (colonoscope) is inserted
into the rectum and guided to the end of the colon (large intestines). This
allows for viewing of the internal lining of colon directly. A Gastroenterologist
performs the test with assistance from a nurse in a hospital, endoscopy
suite or doctor's office. The Gastroenterologist interprets the results.
If specimens are obtained, a Pathologist interprets the results. The test
takes 15-60 minutes to complete.
- Discomfort - An intravenous
line has to be placed. Depending on the level of sedation, there may be
some discomfort as the scope is passed through the colon and as air is instilled
into the intestines.
- Results - The Gastroenterologist's
interpretation is available immediately; 2-3 days for results from tissue
samples obtained.
- Risks of Procedure
- colon perforation is the major risk and occurs in 0.01% to 0.5% of cases.
Other risks include bleeding, infection, and adverse reaction to the medication
used for sedation.
- Average Cost - $$-$$$
- Other names
Lower Endoscopy.
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Indications for Test
- Colon cancer and
colon polyp screening.
- To further evaluate
abnormalities identified in the colon by other tests.
- To identify a source
of diarrhea, bleeding, or anemia (low blood count).
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Preparation
- Only clear liquids
are consumed on the day before the test. After midnight on the morning of
the test, nothing should be consumed, except medications as directed by
your doctor.
- A special medication
(laxative) will be given the day before the test with instructions on how
to take it. An enema may be prescribed on the morning of the test. It is
important that the laxative be taken as prescribed in order for the colon
to be cleaned adequately.
- Aspirin, non-steroidal
anti-inflammatory drugs (aspirin substitutes), blood thinners, anticoagulants,
and iron supplements should not be taken for five days before the test to
reduce the risk of bleeding.
- If the procedure is
performed on an outpatient basis, patient must arrange in advance to have
someone drive them home afterward.
- Patient will be asked
to remove all clothing and wear a hospital gown.
- If patient is at a
high risk of certain types of heart disease, they may be given antibiotics
to prevent infection, since there is a small risk that infectious organisms
from the bowels may penetrate the bloodstream as a result of this procedure
and may travel to the heart.
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Procedure
- After changing into
a hospital gown, an intravenous line is placed for the sedative to be given.
- Monitors are attached
to observe the blood pressure, pulse rate, and oxygen level of the blood.
Supplemental oxygen is given via the nose.
- While lying on your
left side, you are sedated. The doctor examines the colonic lining as it
is projected to a TV monitor as the scope is guide into the colon. Air is
instilled into the colon to aid in visualization of the lining.
- If indicated by the
findings, the doctor can take tissue samples, treat sites that are bleeding,
place stents, or remove polyps (growths).
- During the test,
you may have discomfort related to a feeling of distention. Breathing slowly
and deeply can usually relieve this discomfort.
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After the Procedure
- You are monitored
in the recovery area until the sedation wears off.
- Once the sedation
wears off, you may have someone drive you home.
- You pass large amounts
of gas for several hours after the test.
- You may be advised
to not take aspirin or aspirin substitutes for up to 2 weeks after the test.
- Notify your doctor
immediately if you experience bleeding, severe pain, or fever after the
test.
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Factors affecting results
- An incomplete bowel
preparation will obscure the lining of the colon limiting the doctor's ability
to examine the colon.
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Advantages
- The lining of the
colon can be viewed directly.
- Abnormalities identified
can be biopsied and polyps can be removed during the test.
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Disadvantages
- The preparation for
the test is unpleasant.
- There may be some
discomfort during the test.
- The test is invasive.
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