Colonoscopy is the examination of the large bowel (colon) and rectum to detect any abnormalities. A long, flexible camera with a light on the end is inserted through the back passage (anus). Images are then transmitted to a video monitor for the doctor to view. If an abnormality, such as a polyp, is detected, it will usually be removed at the same time. Tissue samples (biopsy) of abnormal areas of the bowel are sometimes taken and sent for analysis.
Why do I need to have a colonoscopy?
There are a number of reasons why it may be recommended that you undergo a colonoscopy examination. These include:
- To investigate symptoms or changes in bowel habits, such as passing of blood from the rectum, abdominal pain, constipation, or loose motions.
- To screen for large bowel cancer if you are considered at risk. Please discuss with your doctor whether you may benefit from a screening colonoscopy, especially if you are over 60.
- To monitor for colon polyps if you have had these removed before
Preparing for your colonoscopy:
- Medications – Please ensure that we have a full list of your medications at least a week before your colonoscopy, as these may need adjusting or stopping altogether.
Medications containing iron need to be stopped one week before the test and blood thinning medications, such as warfarin and clopidogrel, may need to be stopped or adjusted temporarily.
- Dietary changes – The day before your colonoscopy it is best to avoid solid foods and consume only liquids to minimise solid materials in the colon.
- Laxatives – You will be given instructions to take laxatives starting the day before your procedure. This is to clean out the bowel so that it can be viewed as clearly as possible. Depending on the time of your colonoscopy you will take the laxatives on the night before and/or the morning of the procedure.
What happens during a colonoscopy?
Colonoscopy is usually done as a day procedure. While in the endoscopy room you will lie on your side. You will be given a sedative to relax through a cannula placed in the back of your hand. You will not be totally asleep.
The colonoscope will be passed through the back passage to begin the inspection of the large bowel. Air will be introduced through the colonoscope to aid full inspection of the bowel. Mr Agwunobi will view the magnified images on a monitor and will be able to identify any abnormality. Most colonoscopies are normal, so try not to worry.
Sometimes we may need to take tissue samples (biopsy) to help confirm a suspected diagnosis. Any colonic polyps, identified during the procedure, are usually removed at the same time.
Colonoscopy examinations usually take approximately 20 -30 minutes.
What happens after the colonoscopy?
You will return to the recovery room, where you will closely monitored until most of the sedative effects have worn off. You will then return to your room with instructions on when you can start eating and drinking again.
Mr Agwunobi will visit you to give you your test results. If you have had any sedatives you may not remember everything and having a relative or a friend present may be useful. We will also write to you to confirm what we have discussed.
If tissue samples were taken the results may take another week to come back, at which time you will be notified. Copies of the test results and any ongoing recommendations will also be sent to your GP.
You will then be ready to go home. Please ensure that you have someone to collect you from the hospital if you have had sedation. Stay at home for the rest of the day to recuperate and do not operate any fine machinery or sign important documents for 24 hours.
Are there any complications associated with colonoscopy?
Complications following colonoscopy are very rare but can sometimes occur. These may be related to the sedatives affecting your breathing and/or oxygen levels in the blood, especially in the elderly and those who have pre-existing heart or lung problems.
Very occasionally, a colonoscopy may cause a small tear in the large bowel or bleeding from the site of a biopsy. If you experience any of the following within 48 hours, please contact your doctor immediately:
- Acute abdominal pains, especially associated with fever
- Excessive bleeding from the back passage
Please ensure you consult a healthcare professional before making decisions about your health.