COLONOSCOPY/FLEXIBLE SIGMOIDOSCOPY PATIENT INFORMATION
What is a colonoscopy/flexible sigmoidoscopy?
A colonoscopy is a test which allows Professor Scholefield to look directly at the lining of all of the large bowel (colon). A flexible sigmoidoscopy is limited to approximately 50 cm. In order to do either test, a colonoscope is passed through the anus into the large intestine.
The colonoscope is a long flexible tube (about the thickness of your little finger) with a bright light at the end. Looking down the tube, Professor Scholefield will get a clear view of the lining of the colon and can check whether or not any disease is present.
Sometimes a biopsy is taken – a sample of tissue for analysis in the lab – the tissue is removed painlessly though the endoscope using very fine forceps.
It is also possible to remove polyps during the procedure. Polyps are abnormal projections of tissue, which the lab will examine in more detail.
What should you expect?
To allow a clear view, the colon must be completely empty of waste material. If it is not, certain areas may be obscured and the test may have to be repeated, you will therefore be asked to take all of your bowel prep and considerably increase your intake of clear fluids on the day before your examination, which will help clear your bowel. Whilst this is unpleasant, it is very important. The instruction sheet that you will be given will not only explain clearly how and when to take the bowel prep, but also when you should stop eating and what you can drink. Please adhere strictly to these instructions.
All medication should be taken as normal, including on the day of the procedure. The exception to this is if you are diabetic. Please ensure Professor Scholefield has discussed with you what you should do with your medication.
You will be asked to undress in your room and to put on a hospital gown, leaving your shoes on. Make-up and nail varnish must be removed prior to the test. You may also be asked to remove any jewellery in case a special piece of equipment, called a diathermy unit, is used.
Prior to the procedure Professor Scholefield will check that you understand what is involved and answer any questions you may have to ensure that you understand the test and its implications. If you have any worries or questions at this stage don’t be afraid to ask. You will then be asked to sign a consent form, which allows the test to be done.
During the test
In the endoscopy room you will be made comfortable on the trolley, resting on your left side, the endoscopy staff will stay with you throughout the procedure.
Professor Scholefield will give you an injection into your hand/arm to make you feel sleepy and related. It is not designed to “knock you out” and therefore you will be vaguely aware of the procedure happening. However, it does have the effect of making you fairly drowsy and forgetful, so most people have little if any recall of the event.
The endoscopy staff will clip a small prove to your finger to monitor your pulse and blood oxygen levels during the examination.
When the tube has been gently inserted through the anus into the large bowel, air will be passed through it to distend the colon to give a clearer view of the lining, this may be somewhat uncomfortable and cause some wind like pains, but they will not last.
You may get the sensation of wanting to go to the toilet, but as the bowel is empty, there is no danger of this happening. You may pass some wind but, although this may be embarrassing, remember that we do understand what is causing it.
You may be given oxygen via a nasal cannula (short tube that sits at the “entrance” to your nostrils) or facemask at a very low rate. This is routine.
The test may take up to 30 minutes (colonoscopy) and up to 10 minutes (flexible sigmoidoscopy) to examine all the areas of the colon carefully.
When the examination is finished, the tube is removed quickly and easily.
What complications can happen?
A colonoscopy is a safe procedure, a flexible sigmoidoscopy even safer.
Significant complications from the sedation affecting the heart and breathing occur in less than 1 in 2000 procedures.
The risk of a perforation (hole) of the colon is quoted at approximately 1 in 2000 procedures, higher when a polyp is being removed (1 in 500).
Occasionally bleeding can occur from a biopsy site or when a polyp has been removed. This usually stops spontaneously. Occasionally local diathermy (burning) to the bleeding point is required. This is not something that you would feel or even be aware of.
The most common “complication” is that that the procedure is not completed. This may be due to technical reasons (some colons are particularly tortuous with very sharp angulations which the scope simply cannot get round); due to disease blocking safe progression of the scope; or due to patient discomfort despite sedation. Should this happen, an alternative investigation will be requested, usually a barium enema X-ray. When possible this will be done on the same day as to avoid a second lot of bowel preparation.
Complications are rare but we are obliged to warn you of the risks.
After the test
You will be transferred into your bed and then into the recovery room for 10-15 minutes, where your blood pressure and pulse will be monitored.
You may feel a little bloated with wind pains but these usually settle quickly and you will then be transferred back to your room.
After you have slept off the sedation, you will be given sips of water and then you can eat and drink normally.
Occasionally wind pains/abdominal discomfort can persist for several days. This is unusual, but can be uncomfortable. Should this occur, bed rest is recommended. If you have concerns, you can always telephone the hospital at any time.
When do I know the result?
In many cases Professor Scholefield will be able to tell you the results straight after the test, or if you have been sedated, as soon as you are awake. However, if a sample (biopsy) has been taken for examination, the results may take several days. It is a good idea to have someone with you when Professor Scholefield speaks to you after the test since if sedation has been used, people often find they forget everything that has been said to them. Many do not recollect having the test at all.
It is usually for a follow up appointment to be arranged a week or two after the investigation to discuss the results in more detail, and of course to address the underlying problems which led to the test being done in the first place.
If you are going home after the test it is ESSENTIAL that someone comes to pick you up.
Once home it is important to rest quietly for the remainder of the day.
Sedation lasts longer than you think, so if you have been given an injection during the examination you should NOT:
• Drive a car
• Operate machinery
• Drink alcohol
The effects of the test and injection should have worn off by the next day when most patients are able to resume normal activities.