Understanding
Colonoscopy
What
is a colonoscopy?
Colonoscopy enables your doctor to examine the lining of
your colon (large intestine) for abnormalities by
inserting a flexible tube as thick as your finger into
your anus and slowly advancing it into the rectum and
colon. If your doctor has recommended a colonoscopy, this
brochure will give you a basic understanding of the
procedure - how it's performed, how it can help, and what
side effects you might experience. It can't answer all of
your questions since much depends on the individual
patient and the doctor. Please ask your doctor about
anything you don't understand.
What
preparation is required?
Your doctor will tell you what dietary restrictions to
follow and what cleansing routine to use. In general, the
preparation consists of either consuming a large volume of
a special cleansing solution or clear liquids and special
oral laxatives. The colon must be completely clean for the
procedure to be accurate and complete, so be sure to
follow your doctor's instructions carefully.
Can
I take my current medications?
Most medications can be continued as usual, but some
medications can interfere with the preparation or the
examination. Inform your doctor about medications you're
taking, particularly aspirin products, arthritis
medications, anticoagulants (blood thinners), insulin or
iron products. Also, be sure to mention allergies you have
to medications.
Alert
your doctor if you require antibiotics prior to dental
procedures, because you might need antibiotics before a
colonoscopy as well.
What
happens during colonoscopy?
Colonoscopy is well-tolerated and rarely causes much pain.
You might feel pressure, bloating or cramping during the
procedure. Your doctor might give you a sedative to help
you relax and better tolerate any discomfort.
You
will lie on your side or back while your doctor slowly
advances a colonoscope through your large intestine to
examine the lining. Your doctor will examine the lining
again as he or she slowly withdraws the colonoscope. The
procedure itself usually takes 15 to 60 minutes, although
you should plan on two to three hours for waiting,
preparation and recovery.
In
some cases, the doctor cannot pass the colonoscope through
the entire colon to where it meets the small intestine.
Although another examination might be needed, your doctor
might decide that the limited examination is sufficient.
What
if the colonoscopy shows something abnormal?
If your doctor thinks an area needs further evaluation, he
or she might pass an instrument through the colonoscope to
obtain a biopsy (a sample of the colon lining) to be
analyzed. Biopsies are used to identify many conditions,
and your doctor might order one even if he or she doesn't
suspect cancer. If colonoscopy is being performed to
identify sites of bleeding, your doctor might control the
bleeding through the colonoscope by injecting medications
or by coagulation (sealing off bleeding vessels with heat
treatment). Your doctor might also find polyps during
colonoscopy, and he or she will most likely remove them
during the examination. These procedures don't usually
cause any pain.
What
are polyps and why are they removed?
Polyps are abnormal growths in the colon lining that are
usually benign (noncancerous). They vary in size from a
tiny dot to several inches. Your doctor can't always tell
a benign polyp from a malignant (cancerous) polyp by its
outer appearance, so he or she might send removed polyps
for analysis. Because cancer begins in polyps, removing
them is an important means of preventing colorectal
cancer.
How
are polyps removed?
Your doctor might destroy tiny polyps by fulguration
(burning) or by removing them with wire loops called
snares or with biopsy instruments. Your doctor might use a
technique called "snare polypectomy" to remove
larger polyps. That technique involves passing a wire loop
through the colonoscope and removing the polyp from the
intestinal wall using an electrical current. You should
feel no pain during the polypectomy.
What
happens after a colonoscopy?
Your physician will explain the results of the examination
to you, although you'll probably have to wait for the
results of any biopsies performed.
If
you have been given sedatives during the procedure,
someone must drive you home and stay with you. Even if you
feel alert after the procedure, your judgment and reflexes
could be impaired for the rest of the day. You might have
some cramping or bloating because of the air introduced
into the colon during the examination. This should
disappear quickly when you pass gas.
You
should be able to eat after the examination, but your
doctor might restrict your diet and activities, especially
after polypectomy.
What
are the possible complications of colonoscopy?
Colonoscopy and polypectomy are generally safe when
performed by doctors who have been specially trained and
are experienced in these procedures.
One
possible complication is a perforation, or tear, through
the bowel wall that could require surgery. Bleeding might
occur at the site of biopsy or polypectomy, but it's
usually minor. Bleeding can stop on its own or be
controlled through the colonoscope; it rarely requires
follow-up treatment. Some patients might have a reaction
to the sedatives or complications from heart or lung
disease.
Although complications after colonoscopy are uncommon,
it's important to recognize early signs of possible
complications. Contact your doctor if you notice severe
abdominal pain, fever and chills, or rectal bleeding of
more than one-half cup. Note that bleeding can occur
several days after the procedure.
