Colonoscopy is an endoscopic procedure that visually examines the entire
colon. The preparation is with an oral solution that removes the waste
from the colon. The inside of the colon is then examined for any abnormalities
that may exist. During this procedure, polyps may be safely removed.
This procedure is commonly performed for evaluation of abnormal radiographic
studies, removal of polyps, assessment of bleeding and screening for
Colonsocopy is indicated for patients with inflammatory bowel disease,
GI hemorrhage, polyp removal, screening for colon cancer and evaluation
of abnormal x-rays of the GI tract.
Other Methods of Evaluation
An alternative exam to assess the colon is the barium enema. CT scans
of the abdomen and pelvis are useful but do not always provide sufficient
information about the colon itself. CT scans are not a good test for
looking at tubular structures. They are, however, excellent tests for
looking at structures surrounding the colon and intestines.
Before the Procedure (Preparation)
An oral laxative solution is given the day before the procedure. This
will cleanse the waste from the colon. It is important that the preparation
be followed completely. This procedure examines the inside of the colon.
Thus, if feces are retained, or the preparation is inadequate, areas
of the colon that may be of importance to your health may be missed
or misinterpreted. Usually the preparations given for these are excellent.
If you have specific difficulties with laxatives or the preparations,
please inform your physician beforehand so that alternatives can be
Please make sure that your physician knows well beforehand if you are
taking any blood thinners. Specific instructions regarding the preparation
are available in the section regarding preparations for procedures.
Risks of the Procedure:
Colonsocopy is a safe and highly effective technique. In experienced
hands, this procedure has the following risks:
Allergic reaction to a medication
Perforation of the Colon
Bleeding can occur up to 10 days after the procedure. The chance of
bleeding will increase depending upon the number, location and size
of polyps (if any) which are removed. Some patients have bleeding from
hemorrhoids after the procedure.
An allergic reaction to a medication can occur. This is usually identified
early since blood pressure, heart rate, oxygen saturation and general
clinical condition are monitored during the entire procedure.
Perforation of the colon occurs when a hole is put through the colon.
This can be associated with removal of polyps or simply passing the
endoscope through the colon. This complication will usually result in
a patient being treated in the operating room.
When all patients are included and all of the above are also included,
the chance that one of the above complications will occur is about 1/1,000
Overall, colonoscopy is a well tolerated procedure that has many benefits
and few complications when done for appropriate reasons by an experienced
In general, this procedure takes approximately 30 to 45 minutes to
perform when done by a trained gastroenterologist. The procedure may
take longer depending upon the intervention that may be required for
any individual patient.
During the procedure, a fiber optic endoscope will be inserted into
the anus. The scope will then be advance through the inside of the colon
to the cecum (last part of the colon). Inspection, removal of polyps,
etc. usually occur during withdrawal of the endoscope.
Patients undergoing this procedure usually receive a combination of
intravenous anesthetics. These are usually Demerol (meperidine), Versed
(midazolam) or Fentanyl. The exact combination, dose and frequency of
each of these are individualized for each patient. In most cases, patients
do not remember their procedure or are adequately sedated such that
the discomfort is well tolerated.
During the procedure, the nurse assisting your physician with the procedure
will continuously monitor your heart rate, oxygen saturation and blood
pressure. Thus, should any difficulties occur, your physician and his
team will be aware of the change quickly.