Colonoscopy is the flexible telescopic examination of the bowel. It can allow diagnosis by direct visualization of the lining and additionally biopsies can be taken to aid diagnosis. Colonoscopy can also be therapeutic since if polyps of the bowel are found, then these can be removed using the colonoscopy. So that we can see the bowel adequately obviously the bowel must be emptied with ‘bowel preparation’. The procedure is uncomfortable however, and thus you will be sedated and will not be aware during the procedure, although it is not performed under a general anaesthetic. Whilst the procedure is performed as a ‘day case’ not requiring an overnight hospital stay, the drugs used to sedate are very powerful and you should not drive nor operate machinery for 24 hours afterwards, and will need someone to collect and escort you home.
Are there any alternatives?
The other way to examine the bowel is with a CT pneumocolon. This involves the same bowel preparation but not sedation. Air is introduced into the back passage and CT scan X rays taken. The ‘pictures’ provide a permanent record but fine details and small polyps may be missed particularly if the bowel cleansing is not ideal. Obviously biopsies cannot be taken and if polyps are seen then they have to be removed by colonoscopy. However, colonoscopy can be hampered by severe diverticular disease or a very tortuous colon, and these sometimes prevent a full examination of all of the bowel necessitating a ‘completion CT pneumocolon.
What is the procedure for bowel preparation and colonoscopy?
Good bowel preparation is vital for a successful colonoscopy, which will otherwise be a waste of time. The Moviprep is designed to give you profuse diarrhoea to empty your bowel, and in doing so can give abdominal cramps. You should avoid becoming dehydrated. The preparation starts the day before the procedure:
On the day before your appointment:
Have a meal at mid-day and something light e.g.: Tea and toast in the afternoon, but after 6pm absolutely no solid food, thick or milky liquids until after the procedure. You should drink plenty of clear fluid (including fruit squash, not pure fruit juice or canned fizzy drinks. You may drink clear soup e.g.: Consommé, tea and coffee with a normal amount of milk). At 6 pm take one dose of Moviprep by mixing sachet A and B with one litre of water and add some fruit squash for taste, and drink this over the next hour to 7pm. During the evening from 7 to 10pm drink approximately 1-2 glasses of liquid (half a pint) per hour. It may be sensible to use Vaseline around your bottom in view of the diarrhoea.
On the day of the appointment:
Continue to abstain from eating. At 6 am take the second dose of Moviprep mixing exactly as before with water, and continue to drink fluids up until two hours before your appointment. Do not eat or drink within 2 hours since sedation may be dangerous with a full stomach. Stop all fluids at 10am
What if I take other medicines?
If you take fibre supplements (Fybogel, Regulan, Normacol) then stop these 5 days before. If you take drugs to thin the blood then you need to be sure that the doctor is aware of this. Special arrangements will be made for warfarin, and aspirin can usually be stopped two days before the procedure. Otherwise take all other drugs as usual, and if fasting then take them in a minimum of water. If you have doubts then contact my office during working hours, or the hospital. If you are diabetic you will probably have to avoid insulin or tablets but you must inform the doctor who will advise you. Any drug allergies should be reported when you attend for the procedure.
Are there any complications of colonoscopy?
All invasive procedures can have complications, but thankfully these are rare. You could be over sedated, but we monitor you very carefully and have reversal antidotes available. In approximately one in every 1500 colonoscopies we could inadvertently perforate the bowel with the scope and this would require an operation to repair the perforation. This perforation rate increases slightly when removing polyps, and additionally there could be bleeding requiring operation/ transfusion in every 100 polypectomies. Dehydration or fluid overload can follow the bowel preparation.
Please note if your colonoscopy is booked at The Cavell Hospital, as part of the preadmission procedure you will receive a call from the hospital to carry out a pre admission questionnaire. Please adhere to the timings given to you by Mr Warren for your bowel preparation and admission time.
Any questions and preauthorisation always contact my office 07501 113244(not the hospital)
If post operatively you experience any problems please contact my office on 07501 113244 during office hours. Out of office hours please contact either the Wellington Hospital on 0207 483 5148 The Kings Oak Hospital on 0208 370 9500 or The Cavell Hospital on 0208 366 2122 and ask to be put through to the ward