What is a Colonoscopy?
Colonoscopy is a procedure for diagnosing and treating a variety of problems in the colon and rectum. It is performed using an instrument called a colonoscope which is a flexible tube that is about the thickness of a finger. It is inserted via the rectum into the colon and allows the doctor to carefully examine the lining of the bowel.
If the doctor sees a suspicious area or needs to evaluate an area of inflammation in greater detail, he can pass an instrument through the colonoscope and take a piece of tissue (a biopsy) for examination by a pathology laboratory. Biopsies are taken for many reasons and do not necessarily mean that a cancer is suspected.
What is a Polypectomy?
Polyps are small growths on the lining of the bowel. They are usually benign but occasionally can contain a small area of cancer. Removal is achieved by passing a wire hoop through the colonoscope and snaring the base of the polyp (an electric current may or may not be used to aid the polyp removal. This current cannot be felt and causes no pain).
Is any special preparation needed?
For a successful colonoscopy, the bowel needs to be fully emptied. This will usually mean taking clear liquids as well as a special bowel preparation before the colonoscopy. Your doctor will give you more specific instructions. This preparation can usually be done at home. Failure to carry out the full preparation may result in the cancellation of your colonoscopy.
What happens during a Colonoscopy?
When you arrive for the colonoscopy you will be asked to change into a hospital gown. The examination may be performed with intravenous sedation or a light anaesthetic. Examination of the large bowel lining is made as the instrument is being inserted and again as it is withdrawn. The colonoscopy may take up to 60 minutes especially if polyps are removed.
After the colonoscopy
Following the procedure, you will wake up in the recovery area and once you are fully awake a light meal will be provided. After you have eaten you will be able to go home in the company of another adult. You may not drive yourself home if you have had sedation for the colonoscopy.
Can there be any complications from this procedure?
Colonoscopy and Polypectomy are very safe procedures with very low risk of complications although the following may occur very occasionally:
Depression of breathing may occur with sedation, therefore, the oxygen level in the blood is monitored during the procedure.
Bleeding may occur from the site of the biopsy or polyp removal. It is usually minor and stops on its own or can be controlled by cautery through the colonoscope. Rarely major bleeding can occur either initially or several days later that may require a further colonoscopy or even surgery to stop the bleeding.
Perforation of the colon rarely occurs however this can require abdominal surgery to close the defect in the bowel wall. Great care is taken to avoid this complication.
This is a brief explanation of Colonoscopy/Polypectomy. If you have any questions regarding the procedure, please ask your doctor prior to your procedure.