Physicians use a colonoscope to look inside the large intestine (colon) from the anal opening (rectum) all the way up to the lower end of the small intestine in order to detect polyps or precancerous growths of the lining of the intestine. It can also look for sources of bleeding, inflammation, and ulcers. Conscious sedation is used for this procedure. You will be completely relaxed and feel no sensation.
Preparing for a Colonoscopy
Your colon must be completely empty for the exam to be thorough and safe. Your doctor will give you preparation (prep) instructions. It is very important to follow these carefully. Upon your arrival to the endoscopy suite, you will be interviewed by a nurse. Be sure to tell your nurse if you were unable to complete the prep as ordered. It is very important to know this before the procedure. You may have to follow a liquid diet for 1-2 days prior to the test, and stay away from fibrous foods (fruits, salads, seeds) for 3 days prior to the test.
The prep involves taking a bowel-cleansing agent or laxative (usually in liquid form) the day before the test. These are available at the local drug store and your doctor will recommend the right type to use. This agent will cause a number of bowel movements until you are passing almost clear liquids from the bowel. You may not eat or drink after midnight unless taking the laxative prescribed.
Check with your doctor when booking the test, about taking other prescribed medicines especially blood thinning medicines, aspirin and other anti-inflammatory medicines, as sometimes these are held up to five days before the test.
You should arrive one hour before your exam appointment. Go to the Outpatient Surgery Unit located just inside the hospital's main entrance. Please be sure that you have arranged for someone to drive you home as you cannot drive yourself after the exam. When you check in, you will have the chance to talk with a nurse about your medical history and medications.
Before the procedure, an IV (intravenous line) will be placed in your arm so that the sedative and pain medicine can be given to keep you comfortable. You will lie on your left side for the exam. The doctor will insert a long thin flexible, lighted tube into your rectum, and slowly guide it to the end of the large bowel. A tiny television lens on the scope sends a picture to a TV screen, so the doctor can see the lining of the colon. For better viewing, the endoscope delivers air to inflate your colon (the colon deflates like a balloon when it is empty). You may be asked to move into a different position at times to assist the movement of the scope (although because of your sedation, you may not remember this later. The exam takes approximately 30-60 minutes.
If polyps (or tiny growths) are seen, they can be removed using tiny instruments placed through the flexible scope. Some small tissue samples (biopsies) are usually taken and sent to the hospital laboratory for testing. Any minor bleeding is controlled using a cauterizing instrument or medication through the scope.
Complications are rare, but may include perforation, (puncture) or bleeding of the colon. Gas-like cramping can occur during or after the exam and can be relieved by letting the air escape freely from the rectum.
Following your exam, you will remain to recover for about an hour. You should not drive or operate major equipment for at least 24 hours after your exam. We ask that you do not wear jewelry, but you may wear dentures and hearing aids. Plan to take it easy for the rest of the day. You will be able to eat after the test.