What is Colonoscopy
Colonoscopy
is a procedure used to examine or inspect the bowel and allow for
procedures to be carried out through the colonscope. These procedures
may include taking small tissue samples (biopsy) and removal of polyps.
An alternative method of examining the large bowel is a barium enema.
Colonoscopy has the advantage over barium enema in that it is more
accurate and allows biopsies and removal of polyps at the same time.
How are you prepared
Prior
to the colonoscopy, you will be provided with a preparation kit
containing full instructions. For a few days before the procedure, you
will need to follow a Low Residue Diet. The night before, you will need
to take laxatives and on that evening or morning of the procedure, you
will need to drink a quantity of salty tasting solution which completely
cleanses the colon.
You will
be given sedation via a vein in the arm during the procedure to make you
more comfortable and usually these drugs are administered by an
anaesthetist.
Special Considerations
Uncommonly,
x-ray screening is used during the procedure. Therefore female patients
should advise the nursing staff if there is any possibility of
pregnancy.
You should advise the nursing staff if you are sensitive(allergic) to any drug or other substance.
Medications
You
should cease iron tablets and drugs to stop diarrhoea four days before
the procedure. It is also desirable that you are not taking Aspirin or
N.S.A.I..Dās (arthritis tablets). If you are on these medications, you
should discuss the matter with your doctor. You should also inform your
doctor if you are taking blooding thinning tablets, have heart valve
disease or have a pacemaker implanted. The effect of the oral
contraceptive may by lost as a result of the bowel preparation.
What do we do ?
The
colonoscope is a long and highly flexible tube about the thickness of
your index finger. It is inserted through the rectum into the large
intestine to allow inspection of the whole of the large bowel.
As
a cancer of the large bowel arises from the pre-existing polyps (a
benign wart-like growth) it is advisable that if any polyps are found
they should be removed at the time of the examination. Most polyps can
be burnt off (Polypectomy) by placing a wire snare around the base and
applying an electric current.
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Safety and Risks
Serious complications of colonoscopy are uncommon. Most surveys report complications in 1 in 1,000 examinations or less.
Complication
which can occur include intolerance to the bowel preparation solution
or reaction to the sedatives used. Perforation (making a hole in the
bowel) or major bleeding from the bowel is extremely rare but if it
occurs may require surgery.
When
procedure such as removals of polyps are carried out at the time of the
examination there is a slightly higher risk of perforation or bleeding
from the site where the polyp has been removed.
Complications
of sedation are uncommon and are usually avoided by administrating
oxygen during the procedure and monitoring oxygen levels in the blood.
Rarely however in patients with severe cardiac or chest disease, serious
sedation reactions can occur.
A
number of rare side effects can occur with any endoscopy procedure.
Death is a remote possibility with any interventional procedure. If you
wish to have full details of rare complications, you should indicate to
your doctor before the procedure that you wish for all possible
complications to be fully discussed..
Because
of the cancer risk, it is recommended that all polyps found at the time
of the colonoscopy be removed. However, it may not be possible to
discuss the removal with you at the time of the examination as you will
be sedated. Therefore, if you agree to the polyps being removed during
the procedure, please sign the consent form. If you have any queries or
reservations about this, please inform your doctor.
In the unlikely event of haemorrhage occurring, blood transfusion may be necessary.
Afterwards
The
sedative painkiller you are given before the procedure is very
effective in reducing the discomfort. However, it may also effect your
memory for a short period afterwards. Even when the sedative appears to
have worn off, you may find you are unable to recall details of your
discussion with the doctor. For this reason a relative or friend should
come with you if possible. If you do not recall discussions following
the procedure you should contact your doctor. Lastly you should not
drive that day.
If you have any
severe abdominal pain , bleeding from the back passage, fever or other
symptoms that cause you concern, you should contact your doctor
immediately.