|The Gastroenterology Group, PA
What is a colonoscopy? Colonoscopy is a procedure that enables your physician to examine
the lining of the colon (large bowel) for abnormalities by inserting a flexible tube that is about
the thickness of your finger into the anus and advancing it slowly into the rectum and colon.
What preparation is required? The colon must be completely clean for the procedure to be
accurate and complete. Your physician will give you detailed instructions regarding the dietary
restrictions to be followed and the cleansing routine to be used. Follow your doctor's
instructions carefully. If you do not, the procedure may have to be canceled and repeated later.
What can be expected during colonoscopy? Colonoscopy is usually well tolerated. Your
doctor will give you medication through a vein to help you relax and better tolerate any
discomfort from the procedure. You will be lying on your side or on your back while the
colonoscope is advanced slowly through the large intestine. As the colonoscope is slowly
withdrawn, the lining is again carefully examined. The procedure usually takes 15 to 60
minutes. In some cases, passage of the colonoscope through the entire colon to its junction
with the small intestine cannot be achieved. The physician will decide if the limited examination
is sufficient or if other examinations are necessary.
What if the colonoscopy shows something abnormal? If your doctor thinks an area of the
bowel needs to be evaluated in greater detail, a forceps instrument is passed through the
colonoscope to obtain a biopsy (a sample of the colon lining). This specimen is submitted to
the pathology laboratory for analysis. If polyps are found, they are generally removed. None of
these additional procedures typically produce pain. Remember, the biopsies are taken for
many reasons and do not necessarily mean that cancer is suspected.
What are polyps and why are they removed? Polyps are abnormal growths from the lining of
the colon which vary in size from a tiny dot to several inches. The majority of polyps are benign
(noncancerous) but the doctor cannot always tell a benign from a malignant (cancerous) polyp
by its outer appearance alone. For this reason, removed polyps are sent for tissue analysis.
Removal of colon polyps is an important means of preventing colorectal cancer. Tiny polyps
may be totally destroyed by fulguration (burning), but larger polyps are removed by a technique
called snare polypectomy. The doctor passes a wire loop (snare) through the colonoscope and
severs the attachment of the polyp from the intestinal wall by means of an electrical current.
You should feel no pain during the polypectomy. There is a small risk that removing a polyp will
cause bleeding or result in a burn to the wall of the colon, which could require emergency
What happens after a colonoscopy? After colonoscopy, your physician will explain the results
to you. If you have been given medications during the procedure, someone must accompany
you home from the procedure because of the sedation used during the examination. Even if
you feel alert after the procedure, your judgment and reflexes may be impaired by the sedation
for the rest of the day, making it unsafe for you to drive or operate any machinery. You are not
permitted to drive for 24 hours following a colonoscopy. You may have some cramping or
bloating because of the air introduced into the colon during the examination. This should
disappear quickly with passage of flatus (gas). Generally, you should be able to eat after
leaving the procedure, but your doctor may restrict your diet and activities, especially after
What are the possible complications of colonoscopy? Colonoscopy and polypectomy are
generally safe when performed by physicians who have been specially trained and are
experienced in these endoscopic procedures. One possible complication is a perforation or
tear through the bowel wall that could require surgery. Bleeding may occur from the site of
biopsy or polypectomy. It is usually minor and stops on its own or can be controlled through the
colonoscope. Rarely, blood transfusions or surgery may be required. Other potential risks
include a reaction to the sedatives used and complications from heart or lung disease.
Localized irritation of the vein where medications were injected may rarely cause a tender lump
lasting for several weeks, but this will go away eventually. Applying hot packs or hot moist
towels may help relieve discomfort. Although complications after colonoscopy are uncommon,
it is important for you to recognize early signs of any possible complication. Contact your
physician who performed the colonoscopy if you notice any of the following symptoms: severe
abdominal pain. fever and chills, or rectal bleeding. Bleeding can occur several days after