KOLOREKTUM.CZ | COLORECTAL CANCER SCREENING [ISSN 1804-0888]
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For the public COLORECTAL SCREENING What should I expect? Screening colonoscopy

Screening colonoscopy

The screening colonoscopy is definitely much more reliable than the faecal occult blood test (FOBT). A colonoscopic examination even allows the removal of suspect outgrowths (polyps) from the intestinal wall, which could later turn into carcinomas. However, colonoscopy is not very popular among the public and many patients are very afraid of it. But these fears are often groundless. First of all, it must be taken into consideration that each person has another pain threshold. For this reason, some people don’t have any problems with colonoscopy, while others consider it to be a very disagreeable procedure. The combination of analgesics and sedatives, however, make the whole procedure bearable even for more sensitive individuals. (General anaesthesia can be also used as a last resort.)

Colonoscopy is usually done as an outpatient or day case. It is a routine test which is commonly done. You will usually be given a sedative to help you to relax. This is usually given by an injection into a vein in the back of your hand. The sedative can make you drowsy but it does not “put you to sleep”. It is not a general anaesthetic.

You lie on your side on a couch. The operator will gently push the end of the colonoscope into your anus and up into the colon. The operator can look down the colonoscope and inspect the lining of the colon. Also, modern colonoscopes transmit pictures through a camera attachment onto a TV monitor for the operator to look at.

Air is passed down a channel in the colonoscope into the colon to make the inside lining easier to see. This may cause you to feel as if you want to go to the toilet (although there will be no faeces to pass). The air may also make you feel bloated, cause some mild “wind pains”, and may cause you to pass wind. This is normal and there is no need to be embarrassed as the operator will expect this to happen.

The operator may take biopsies of some parts of the inside lining of the colon – depending on why the test is done. This is painless. The biopsy samples are sent to the lab for testing, and to look at under the microscope. Also, it is possible to remove polyps which may be found by an instrument attached to a colonoscope. At the end of the procedure the colonoscope is gently pulled out.

A colonoscopy usually takes about 20-30 minutes. However, you should allow at least two hours for the whole appointment to prepare, give time for the sedative to work, for the colonoscopy itself, and to recover. A colonoscopy does not hurt, but it can be a little uncomfortable, particularly when the colonoscope is first passed into the anus.

You might also want to have a look at our interactive guide to colorectal cancer screening.

Last updated on 2 February 2015