Colonoscopy

Colonoscopy

Colonoscopy is a procedure done under sedation which allows the doctor to see inside your large bowel (colon) and examine the lining of it directly, using a colonoscope (a long, thin flexible tube which has a light source and camera built into it). The colonoscope is placed into your rectum (bottom) and the doctor then guides it around your large bowel while viewing the images on a video screen.

The doctor will look for any areas that seem abnormal and will take biopsies (small samples of tissue) if needed. Removal of polyps and treatment of bleeding or piles can also be undertaken. Any tissue samples that are taken are sent to the laboratory for examination.

Your doctor may suggest you have a colonoscopy if you have experienced any of the following problems:

  • Changes in bowel habit
  • diarrhoea or constipation
  • Bleeding from the bowel, either seen or unseen (occult)
  • Anaemia
  • Abdominal pain
  • Family history of bowel cancer
  • Previous treatment for polyps or bowel cancer
  • Ulcerative colitis or Crohns disease

Rarely complications can occur after a colonoscopy. They can include:

  • Perforation (tearing) of the bowel wall by the colonoscope which can cause leakage into the abdomen, especially after endoscopic therapies such as biopsies, polypectomy, diathermy or dilatations
  • Bleeding may occur from the site of the biopsy or polyp removal
  • Allergic reaction to the sedative
  • A polyp or lesion can be missed

If you would like further clarification of these complications please discuss them with your specialist or nurse.

What Happens?

It is important that the bowel is completely empty of faecal material for the procedure to be thorough and safe. If it is not entirely clean certain areas may be obscured. The preparation for a colonoscopy procedure will involve making changes to your diet for three days prior to the procedure. We will send you specific information with the bowel preparation you have to drink, however be prepared to be at home from 3pm the day before your procedure to start the bowel preparation (laxative). This will allow you to empty all faecal material from your bowel and enable the doctor to get clear views of the lining of your bowel wall. All the instructions are given in a written patient information brochure and phone support is available.

In addition, it is important to inform Waitemata Endoscopy prior to your procedure if you have any of the following:

  • An allergy or bad reaction to medicines or anaesthetics
  • Take medication to thin your blood including dabigatran/pradaxa, warfarin or aspirin
  • Prolonged bleeding/clotting disorders or excessive bleeding
  • Diabetes
  • Heart and lung problems including artificial heart valves and pacemakers
  • Artificial hip or knee joint replacements
  • If you are pregnant or breast-feeding

On admission into Waitemata Endoscopy your medical history is recorded by a nurse and further information given in the form of a patient DVD. A consent form is discussed and signed indicating that you understand the procedure and complications involved and consent to have the procedure performed.

In the examination room you will be given medication (a sedative and a pain medication) to make you sleepy and drowsy. This will be given by a small injection into a vein in your arm or hand. The colonoscopy can take 15 to 60 minutes and you will be assisted and observed by two nurses. Your heart rate and oxygen levels will be monitored during the procedure. The colonoscope is gently inserted into the bowel which is inflated with C02 to obtain a good view.

After the procedure you will be taken into the recovery area to sleep off the sedative. The endoscopy nursing staff will continue to monitor you until you are awake enough to get dressed and be given light refreshments. Because you will have been given sedation you are not allowed to drive a car, operate machinery or make any important decisions for 12 hours as the sedation will impair your reflexes and judgement. Therefore you will need to arrange for someone else to drive you home and it is recommended to have an adult with you at home afterwards. You are not able to take public transport alone.

If biopsies or polyps are taken for examination, your GP and specialist will be sent the results within 5 to 7 working days. A medical typed report of the procedure will be sent to your GP and specialist. Follow-up information and recommendations will be given by the specialist prior to discharge from Waitemata Endoscopy.

For a copy of our brochure, please download the PDF here.