Colonoscopy is a diagnostic test in which a flexible lighted tube is inserted through the anus to examine the colon. Its value is that it gives the highest detection rates for diagnosing sources of hidden or obvious rectal bleeding. Colonoscopy is also performed to diagnose abdominal pain, check for diverticulosis and its complications, and to follow patients with inflammatory diseases of the colon.

Colonoscopy can be therapeutic when a polyp is found. Removal of polyps is now known to help to prevent colon cancer from occurring. Polyps may be removed by instruments inserted through the colonoscope. Superficial bleeding blood vessels, which cause hidden or obvious bleeding, may also be treated with the colonoscope.

There are two unusual complications of colonoscopy. Bleeding may occur. This often is after treatment of a polyp, biopsy of a tumor, or treatment of a bleeding superficial blood vessel. Occasionally hospitalization and further treatment is necessary for heavy bleeding with a rare need for blood transfusion or surgery. Although the colonoscope is flexible, it may at times not be able to pass through the colon. This occurs if the colon is extensively coiled. These coils may be scarred into loops, which cannot be unfolded especially in some patients who have had prior abdominal surgery or abdominal inflammation causing illnesses. When this situation is found, the procedure is stopped. Complete colonoscopy is not possible in every patient. Almost all people who have had surgery or inflammations have uncomplicated colonoscopy. An unusual complication is for the colonoscope to perforate one of the colon coils. This complication can require operation to repair, although many patients can seal a perforation spontaneously with several days of hospital care.

Prior to colonoscopy you will be given instructions in how to clean out your colon. If the colon is not clean, colonoscopy loses its value because abnormalities may be hidden by stool.

In most cases, intravenous fluids and sedation are given during colonoscopy. Most patients sleep during the procedure and have no memory of the procedure having been performed. Explanations as to the findings are best given on another day, because frequently you will not have a complete memory of what you have been told. Please call the doctor’s office with any questions. You should not drive on the day that sedation is given because your reflexes will be slower. You should plan on resting at home after the procedure.

After the procedure you will be allowed to eat. You should follow your appetite and if you do not feel like eating solids, you should stay on liquids until your appetite returns.

Passage of large amounts of gas by rectum and passage of traces of blood are normal occurrences after colonoscopy. The colonoscope puts air in the colon so that the walls may be more completely examined. Because of the cleaning out of the colon, it is usual to not expect a bowel movement for several days after the procedure.

If you have further questions, please discuss them with the doctor.