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 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.
Colonoscopy
