Colonoscopy

This is a procedure which allows the doctor to see inside your large bowel and examine the surfaces directly and take biopsies (samples of tissue) if needed.

The colonoscope is a flexible plastic-coated tube approximately 1cm in diameter which has a tiny camera (video chip) attached that sends images to a video monitor. Special instruments can be passed down the endoscope to obtain a biopsy (a tiny tissue sample) and to remove polyps. The colonoscope is completely cleaned and disinfected between each patient to avoid the risk of transmission of serious diseases.

Before the procedure you will need to follow a special diet and take some laxatives (medicine to make you go to the toilet). Detailed instructions will be given. The bowel needs to be completely clear for the examination to be safe and accurate. Therefore it is important that the instructions you are given are followed carefully. You will be given a sedative (medicine that will make you sleepy but is not a general anaesthetic). The tube is passed into the rectum (bottom) and gently moved along the large bowel. The procedure takes from 15 - 30 minutes. Your oxygen levels and heart rhythm are monitored throughout. The procedure is performed in a day stay operating theatre.

Patients undergoing colonoscopy sometimes experience a feeling of wind pain
or cramp as the endoscope goes around the corners in the bowel. This discomfort is not for the duration of the colonoscopy. It is important following a colonoscopy to pass the wind that may be trapped in the bowel.

After the procedure you will be observed for 30 - 60mins - your total stay at the clinic is usually 2 hours. When you are awake your specialist will discuss your examination results with you. Sometimes you do not clearly remember the discussion or even that the specialist spoke to you (due to the sedative) and hence a written summary will also be given to you for your reference. A detailed report will also be sent from your specialist to your GP or referring doctor.

A light snack will be served before you leave the clinic. You must not drive following the procedure and it is recommended that you have someone stay with you the night of the procedure. You may return to a normal diet immediately following discharge, unless directed otherwise. It is important to rehydrate following the procedure - drink plenty of fluids. Most people are able to resume normal activities the following day.

Serious complications of colonoscopy are rare, at less than one in 3,000 examinations. Rare problems are an allergic reaction to the sedative, bleeding after removal of a polyp and perforation (tearing) of the bowel wall. The most common problem is intolerance to the bowel preparation. Some people develop dizziness, headaches or vomiting.

Colonoscopy is considered to be a very accurate test. However, there is a small risk that an abnormality may not be detected.

Laboratory results from any biopsies taken will be sent to your GP or referring doctor and the clinic for your specialist to review (can take up to 5 days).

For further information about the colonoscopy procedure see Endoscopy Auckland or MercyAscot Endoscopy.