Procedures / Colonoscopy


This is an examination of your large bowel (colon).  During colonoscopy, you will usually be given sedation and analgesia (pain relief) to make you feel relaxed and drowsy.

This test is a very accurate way of looking at the lining of your large bowel (colon) to establish whether there is any disease present.  This test also allows us to take tissue samples (biopsies) for analysis by the pathology department if necessary.

The instrument used in this investigation is flexible and is called a colonoscope.  Within each scope, there is an illumination channel, which enables light to be directed on to the lining of your bowel, and another which relays pictures back on to a television screen. This enables the endoscopist to have a clear view and to check whether or not disease or inflammation is present.

During the investigation, the endoscopist may need to take some samples from the lining of your colon for analysis.  This is painless.  The samples will be retained.  Any photographs will be recorded in your notes.

Why do I need a colonoscopy?

You may have been advised to undergo this investigation of your large bowel to try and find the cause for your symptoms, help with treatment and, if necessary, to decide on further investigation.  A colonoscopy is used to investigate a variety of symptoms, for example:

  • Persistent diarrhoea
  • Abdominal pain
  • Change in bowel habit
  • Bleeding from the back passage
  • Polyps
  • Strong family history of cancer
  • Follow-up inspection of previous disease
  • Assessing the clinical importance of an abnormality seen on an X-ray.

What preparation do I need to do?

It is advised that you wear loose-fitting clothing, as this is more comfortable for you during and after the test.  Please bring a dressing-gown and slippers if you can.

To allow a clear view during the test, your bowel must be empty.  Therefore it is essential that you follow the bowel preparation instructions.  The instructions are included and the bowel laxative should be started the day before the test.

It is important to increase your intake of clear fluids on the day before your test (examples of clear fluids are included at the back of this booklet).  You may drink water up to 2 hours before your test.  A list of clear fluids is also given in the bowel preparation (MoviPrep) instruction leaflet.

What can I expect after a gastroscopy?

You will be escorted into the procedure room, where the endoscopist and the nurses will introduce themselves and you will have the opportunity to ask any final questions.

The nurse looking after you will ask you to lie on your left side and will place the oxygen monitoring probe on your finger.

The sedative drugs will be administered into a cannula (tube) in your vein.

The colonoscopy involves manoeuvring the colonoscope around the entire length of your large bowel.  There are some bends that occur naturally in the bowel and negotiating these may be uncomfortable for a short period of time but the sedation and analgesia will minimise any discomfort.

Air is gently passed into the bowel during the investigation to ease the passage of the colonoscope.
During the procedure, samples may be taken from the lining of your bowel for analysis in our laboratories.  These will be retained.  Any photographs will be recorded in your notes.

Are there side effects or complications?

Colonoscopy is an invasive investigation and because of this it has the possibility of complications. These are very rare but it is important that we tell you about them, so that you can consider this information before you consent to treatment.

Dr Patodi will have considered the risks carefully.  The risks must be compared to the benefits of having the procedure.  The risks can be associated with the colonoscopy itself and with the administration of the sedation.

    Disclaimer: This article is for information only and should not be used as a substitute for professional medical care by a qualified doctor or other healthcare professional. ALWAYS check with your doctor if you have any concerns about your condition or treatment.

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