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About your colonoscopy examination

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What is a colonoscopy?

This is a simple examination to view the inside of the colon (large bowel). A camera on a flexible tube will be passed into the anus. The entire large bowel is then visualised, using air or CO2 gas to distend it. For the examination you will be offered a light sedative and painkiller or nitrous oxide (gas and air). The sedative is administered to make you feel relaxed and drowsy, not to put you to sleep. Following the procedure you may feel a little bloated with wind. This is normal.

To enable us to see inside your colon effectively, you will need to take the bowel preparation that comes with this leaflet.

Who will be performing my procedure?

The procedure will be performed by specially trained healthcare professionals. Occasionally, supervised doctors or nurses in training will be performing the procedure. Brighton and Sussex University Hospitals (BSUH) is attached to the Brighton and Sussex Medical School (BSMS) and as such medical students may be observing. If you do not want students present, please inform the nursing staff on your arrival.

Are there any significant risks?

These telescopic examinations are very safe but some risks are associated with the procedure:

These include a reaction to the sedative which can affect 1:2500 people. This may affect your breathing or blood pressure, both of which are closely monitored during any procedure. A tear or perforation in the lining of the bowel can occur in any telescopic test. The national figures for this are 1:1500. If this does occur you will need to be admitted to hospital and may require an operation to repair the tear.

Minor bleeding is common if biopsies or pieces of tissue (polyps) are removed. This bleeding usually stops by itself. More significant bleeding can occur in 1:1000 procedures and may require admission to hospital and a blood transfusion. There is also a risk of small lesions being missed. This is currently quoted as approximately 5%. Specialist equipment and training reduce all these risks considerably. The figures quoted here are national averages and for BSUH are much lower. Please speak to the doctor or nurse performing your procedure if you have any concerns.

What are the benefits?

This procedure allows direct visualisation of your bowel. Biopsies may be taken and polyps removed, if necessary.

Are there any alternatives?

The alternative to colonoscopy would be CT colonography. This is a type of scan which requires you to take mild bowel preparation in order to clear the colon of waste. It does not allow tissue to be sampled or removed.

How do I prepare for my examination?

  • Follow the instructions given to you with the bowel preparation and this leaflet.  The preparation you have been given will give you loose bowel movements, so you will need to go to the toilet frequently. Keep this in mind and plan your day so that you can remain within easy reach of a toilet.
  • It is very important that you read the bowel preparation instructions very carefully. If the large bowel is not cleared effectively, your examination may need to be repeated.
  • Do not take any medicine within an hour of the bowel preparation as it may not be absorbed.
  • Blood thinners: Aspirin 75mg once per day can always be continued. Others e.g. Warfarin, Clopidogrel, Dabigatran, Rivaroxaban can usually be continued for diagnostic tests. If you have/are expecting to have polyps removed contact Endoscopy. Contact Endoscopy if you have not received clear instructions from your consultant or GP.
  • ACE inhibitors: e.g. Perindopril, Captopril, Enalapril, Lisinopril, Ramipril. Do not take on the day of the procedure or the day before.
  • Diuretics / water tablets e.g. Frusemide, Bumetanide. Do not take on the day of the procedure or the day before.
  • Iron tablets: Stop 7 days before the procedure.
  • Constipating agents e.g. Loperamide, Codeine. Stop 5 days before the procedure.
  • Prednisolone: if you take less than 20mg, increase your dose to 20mg the day before, the day of, and the day after the procedure. If you take more than 20mg take your normal dose.
  • Methylprednisolone, Dexamethasone, Hydrocortisone, Addison’s Disease, pituitary patients: contact Endoscopy for individual advice.
  • Contraceptive pill: May not work for a week after bowel preparation. Use other methods.
  • Diabetes medication: If you are a diabetic on medication (insulin or tablets) and need advice, please contact the health professional who looks after you regarding your diabetes. If you do not have a health professional who looks after you regarding your diabetes, please call the hospital on 01273 696955, extension 64205, and speak to one of the Diabetes Nurse Specialists.
  • Pregnancy or breastfeeding:  Contact Endoscopy for individual advice. If you have any enquiries, please contact the endoscopy unit on the numbers shown on the front and back of this booklet.
  • If you have ever been informed that you are at risk from CJD or vCJD for public health purposes, please call us on 01273 696955 extension 64570 (Royal Sussex County Hospital) or 01444 441 881 extension 68187 (Princess Royal Hospital).

What should I bring with me to the unit?

  • If you are having sedation for your procedure you will need someone to act as an escort and stay with you for the remainder of the day and overnight. Your escort must come up to the unit to collect you. We cannot take you down to meet them.
  • A list of ALL your medication.
  • Your reading glasses.
  • Wear loose and comfortable clothing.
  • Music if you find it relaxing.
  • Do not bring any valuables with you.

Can I park at the hospital?

Parking space at the Royal Sussex County Hospital is very limited, so please set off in plenty of time for your appointment and be prepared to wait in the car park queue. Alternatively, your escort may drop you off at the Millenium Wing and then return to the unit to collect you later.

There is ample parking at the Princess Royal Hospital.

If you have sedation for your procedure and intend to go home by taxi, you will need a responsible adult to accompany you, as taxi companies will not accept responsibility for you travelling alone. Although you may use public transport to come to hospital, we strongly advise you not to travel home by bus or train, following sedation.

What happens when I arrive in reception?

Please report to the desk. Our receptionist will check your details and ask you to take a seat in the waiting room. You will then be called through by a nurse or health care assistant, who will explain the examination to you and ask you some questions about your medical history. If you are having sedation, please ensure that you have your escort’s contact details with you so that we can call them when you are ready to be collected. You will be asked to sign a consent form before the examination. Please see a copy of the form at the back of this booklet. If you have any questions or if there is anything at all that you don’t understand, please ask.

You will have time to recover and will be offered a drink and a biscuit. You will need to rest for the remainder of the day and refrain from smoking and drinking alcohol. If you have a gluten allergy please bring something to eat. If you have had a sedative you must not drive, sign legal documents or operate machinery for 24 hours.

An explanation of the examination findings will be given to you by a nurse or doctor. You may need to make an appointment to see your GP, who will receive a report of the examination within a week.

Will it hurt?

Endoscopic examinations and procedures can be uncomfortable, so we have a variety of interventions at our disposal to make it more comfortable for you. Sedation can be given for colonoscopy. Alternatively we can give you some gas and air (nitrous oxide) if It is very important that you read the bowel preparation instructions very carefully. If the large bowel is not cleared effectively, your examination may need to be repeated.We can also give intravenous pain killers. Please let us know if you are uncomfortable in any way and we will do our best to help you. After a colonoscopy you may suffer from bloating and wind. These effects should disappear after a few days but you will be given written aftercare advice when you go home, which tells you what to do if your symptoms do not settle.

How long will it take?

Examination / procedure times vary. A simple diagnostic examination should take between 10 and 30 minutes but a more complicated examination, involving endoscopic treatment, such as removal of polyps, can take anything from 30 minutes to 90 minutes, or longer. If your examination involves having treatment, your recovery time will also be slightly longer. This is why you should be prepared to be in the unit for possibly 3-4 hours.

When will I get my results?

Results from biopsies taken, or polyps which have been removed, may take up to 8 weeks to come back from the laboratory. The findings are reviewed by your consultant, who will then arrange follow up. This could be a clinic appointment to discuss your results or it could be a letter explaining your results. Please do not phone our recovery area during this time: we are unable to give any biopsy results over the telephone. If you have not heard anything after 8 weeks, and you are worried, please contact your GP, who will be informed of your results.

What do I do if I need to cancel or change my appointment?

If you need to cancel or change your appointment please call us on 0300 303 8517.

Your comments and suggestions

If you have any concerns about your treatment or care, please bring them to our attention. We will do our best to help.

If you feel you would like some support with raising your concerns, the Patient’s Advocate is available to speak on your behalf.

You can contact the Patient’s Advocate by telephone between 10am and 4pm on: 01444 441881, extension 65909 (Princess Royal Hospital) or 01273 696955, extension 64029 or 64588 (Royal Sussex County Hospital), or by email at for either site.

We always welcome new ideas and suggestions. Please let us know if you feel there are ways in which we could improve our service.

Who can I contact for further information and advice?

Thank you for taking the time to read this information: if there is anything at all that you don’t understand, or you have any questions, please ask a nurse at the unit, or call us on 01273 696955, extension 64570 for the Royal Sussex County Hospital and 01444 441881, extension 68187 for the Princess Royal Hospital.

This information is intended for patients receiving care in Brighton & Hove or Haywards Heath.

The information here is for guidance purposes only and is in no way intended to replace professional clinical advice by a qualified practitioner.

Publication Date: October 2021

Review Date: July 2024

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