Gastroenterology - Colonoscopy

A colonoscopy is a test which allows the endoscopist to look at the lining of the colon (large bowel).

Your stay on the endoscopy unit could be up to 2 hours or more depending on individual recovery time, also please note that your appointment time is only your admittance time.

A colonoscopy is done by passing a long flexible tube (endoscope) which is approximately the thickness of your index finger, into the bowel via the anus (back passage). Air is then passed into the bowel to give a clear view of the lining. This may cause ‘wind’ like discomfort, but it should not last long.

You may also get the sensation that you want to go to the toilet but as the bowel is empty there is no danger of this happening. You may pass some wind, but although this is embarrassing, remember it is normal and the staff understand what is causing it.

There may be periods of discomfort as the tube goes around bends in the bowel. Usually these will ease once the bend has been passed. If you are finding the procedure more uncomfortable than you would like, please let the nurse/doctor know and you may be given some more sedative or analgesia.

In order to make the procedure easier you may be asked to change position (for example roll onto your back). However, if you make it clear that you are too uncomfortable the procedure will be stopped.

The examination usually takes about 30 minutes although it can sometimes take longer.

During the procedure

In some cases it may be necessary to take small samples of tissue (biopsies) using tiny forceps, which are then sent to the laboratory for testing. The taking of biopsies is usually painless and very safe.

It may be necessary for the endoscopist to remove polyps from the lining of the bowel. These polyps are projections of tissue, which grow on the lining of the bowel and are removed using a small wire loop. Removing polyps is usually painless.

What are the possible risks?

Complications can develop during or after the procedure. Every effort is made to prevent, recognise and treat these.

• Colonoscopy procedures carry a small risk (1 in 1000 cases) of haemorrhage (bleeding) or perforation (tear) to the bowel. These are more likely to occur after the removal of a polyp
• Risk of stoma formation because of surgery if complications occur due to a perforation
• Slight rectal bleeding is normal following biopsies and should settle down over the next 24 hours
• Sometimes the base of a polyp can bleed; this can usually be stopped through the colonoscope (although you may require hospital admission)
• Occasionally we need to readmit a patient who has bled at home and requires further treatment in hospital
• Another rare complication is an adverse reaction to the intravenous sedative and analgesic drugs
• Although colonoscopy is a relatively safe procedure, rare deaths resulting from complications have been reported. Any worries you may have about this can be discussed in detail with your GP or endoscopist performing the procedure

If you are going abroad within two weeks of your colonoscopy advise the nurse on admission OR if you are having a planned polypectomy please contact the endoscopy unit prior to your appointment.

What are the benefits?

This test gives a direct view of the lining of the large bowel. We can take samples of the bowel lining for examination under the microscope. We can snare and remove polyps.

Alternatives

• CT colonography may be done as an alternative, but sample tissues cannot be taken during this procedure
• X-rays and scans might be required at other stages in your investigation

If you have any further questions or require any further information, then we can discuss this with you at your next hospital visit.

Bowel preparation

You will need to collect your bowel preparation approximately 7 days before your procedure from the hospital you are attending. You will be given instructions both written and verbally. It is important that you understand this information as your bowel needs to be as clean as possible. If it is not done correctly, it could result in you having to undergo the procedure again. If your bowel preparation is given to you at clinic and you are unsure about how to take it, then please do not hesitate to contact the endoscopy unit for further instruction. Please bring your appointment letter and laxative letters with you when you collect your bowel preparation.
 
It is important to follow the instructions given to you on collection of your bowel preparation, or this could result in your procedure being cancelled on the day due to poor bowel preparation. Please note:

1. You are only allowed clear fluids whilst taking bowel preparation (NO food) and;
2. You need to stop drinking any fluids for 4 hours before your appointment time

Medication

• If you take anticoagulant treatment e.g Warfarin please contact your consultant or the anticoagulant clinic that deals with your medication
• If you take Clopidogrel please contact your consultant or the endoscopic unit for specific instructions
• Please make sure that the doctor requesting the procedure and the one performing the procedure are both aware that you have been on anticoagulants and what instructions you have been given regarding this medication
• If you are diabetic on medication or insulin please contact your Diabetic Nurse for specific instructions
• If you take iron tablets stop taking them one week before the test
• If you are taking Codeine tablets please avoid taking them unless they are essential one week before the test
• If you have a latex allergy then please contact the relevant Booking & Scheduling Team as your admission date/time will be affected

You must keep taking any essential prescribed tablets unless advised otherwise.
 
Colonoscopy can be performed with or without sedation.

You will be offered sedation and pain relief (analgesia) for this examination in order to help you relax. This involves a drug being given through a needle (usually in the back of the hand).

If you decide to have sedation, please be aware that it is only a conscious sedation, not a general anaesthetic. Sedation will only make you feel drowsy and not put you to sleep, but if you are given sedation for your own safety please comply with the following:

• After the test you will spend approximately 1 hour on the unit recovering from the procedure
• You need a responsible person to accompany you home and stay with you for at least 24 hours after the sedation, as the sedation can remain in the bloodstream for this length of time. If you are a main carer, please arrange an alternative carer
• If you wish to have sedation and have no-one to be with you for the 24 hours after the procedure then you must mention this when you confirm the appointment (alternative arrangements may be required)
• You must not sign any legal documents for at least 24 hours
• You must not return to work, drive or drink alcohol for at least 24 hours after the sedation
• For some patients, sedation is not advised. The doctor performing the examination will discuss this with you
• You can also have the procedure without sedation and carry on your normal daily activities if you prefer
• Entonox may be offered as an alternative for suitable patients. This allows you to carry on with your normal activities including driving after 30 minutes

What do I need to bring with me?

Please bring any medication and a medication list with you on the day of your procedure. You may need to take your medication during your stay. You may bring your dressing gown and slippers.

Contact details:

Fairfield General Hospital - 0161 778 3341
Rochdale Infirmary - 01706 517550
The Royal Oldham Hospital - 0161 627 8513
Salford Royal Hospital - 0161 206 5959
Community Diagnostic Centre (CDC) Oldham - 0161 778 5615
Booking & Scheduling Team (Fairfield, Rochdale and Oldham Only) - 01706 906788
Booking & Scheduling Team (Salford only) - 0161 778 5402