What is colonoscopy?
Colonoscopy is a procedure used to examine the inside of the large bowel known as the colon. The colonoscope is a flexible tube with a tiny video camera on the end; this allows us to see the picture from the tip, on a monitor screen. An alternative method for looking at the bowel is Barium enema X-ray but colonoscopy is more accurate. Only colonoscopy can be used to take biopsies or remove polyps.
Preparation for your Colonoscopy.
For successful colonoscopy the bowel must be empty and clean so that we can see and not miss any problems present. If you are prone to constipation start Movicol, 3 days before the procedure, and 1-3 sachets a day. You can buy this at the chemist without a script.
All patients having colonoscopy start the preparation as per Moviprep Bowel Preparation instructions. i.e. no solid food, clear fluids only, 1 day before the test. There is an additional leaflet for this.
Carefully follow the bowel preparation instructions from us.
On the day of the test you may drink water, maximum 200 ml per hour but stop 3 hours before the test. Important medications, e.g. blood pressure pills can be taken with a small sip of water 4 hours before the test. Diabetics should notify this surgery prior to the test as you may need to adjust your diabetes medication dose.
If you have any important medical problems or you wish to discuss the test prior to the procedure day, you can have a consultation with Dr Hing or Dr Shew.
You should arrange for someone to take you home after the test. In view of sedation used for the test you can not drive a car for 24 hours.
What happens during colonoscopy?
An anaesthetist will give you sedatives via a small cannula in the back of your hand. It will make you sleepy and affects your memory. It is not the same as a general anaesthetic but gives adequate relief of pain. We will tell you some of your results on the same day.
The colonoscope is carefully manoeuvred from the rectum to the end of the colon called the caecum. Sometimes it is not possible to safely get all the way around as the bowel is too loopy. Air is pumped in to open the bowel so we can see the lining; this can cause a little discomfort during or after the test. Passing flatus or wind helps.
If needed, photographs or small biopsies can be taken, the latter are sent to the laboratory to be analysed. You cannot feel the biopsies being taken. Polyps (wart like growths from the bowel lining) if not too large can be removed during the procedure. Most polyps can be burnt off and retrieved by using a wire snare at the base of the polyp and applying an electrical current. You can not feel this being done. It is advisable to remove polyps, as they are precursors to bowel cancer. When you sign the consent form for colonoscopy you will also be consenting to polyp removal if necessary.
All equipment is high level disinfected or steam sterilised in accordance to The Australian and New Zealand Standards AS/NZS 4187:2014 and the NSW Ministry of Health Infection Control Policy and the Gastroenterological Society of Australia guidelines.
Safety and risks
With any medical procedure complications can occur. For inspection of the bowel alone, complications of colonoscopy are uncommon, occurring in less than 1 in 3,000 tests. The most important risk is perforation (making a hole in the bowel) which may need an operation. Major bleeding is rare. A reaction to the sedation can occur but all patients are watched very closely, a mask gives oxygen and a small probe monitors the pulse rate. This risk is increased in patients with severe heart or lung problems.
When polyps are removed there is a slightly higher risk of perforation or bleeding. A number of rare side effects can occur with any endoscopic procedure and can be discussed if you wish.
You should also consider the risk associated with not having the test eg. missing a serious problem that can be treated as soon as possible.
The sedation is very effective at reducing any discomfort, however it can affect your memory for some time afterwards. If you do not remember your talk with the doctor, ring him the next day or make an appointment to come back in.
Because of the sedation you should not: drive, use machinery, go back to work or sign legal documents until the next day.
In the rare event you have any: severe pain in the abdomen, especially if it is not getting better, bleeding or other symptoms that worry you, contact us immediately or go to hospital.