Colonoscopy for diagnosis of intestinal symptoms

Colonoscopy is the visual inspection of the entire colon and rectum with a steerable flexible 160 cm instrument.  Biopsies (tissue samples) can be taken and colon polyps removed through the instrument.  Occasionally, the physician will actually enter the end of the small bowel to assess its lining as part of the examination.  Colonoscopy takes anywhere from 15 minutes to one hour to perform, depending upon the nature of the individual colon being examined.  A full cleansing of the colon is required the day before in order to provide the clearest view for the examiner and to optimize safety during polypectomy.  A fluid only diet is begun a couple of days before the procedure as well (see patient instructions).

Short-acting intravenous conscious sedation is generally given with colonoscopy in order to reduce discomfort (see conscious sedation).  The patient is awake, but sleepy, and is carefully monitored by Pezim Clinic staff during and following the procedure.  Most patients are ready to leave the Clinic one and one-half hours after they arrive, but must not drive for the remainder of the day because of the effects of the sedation.

Colonoscopy is a low risk procedure, but it is not zero risk.  The risk of perforation of the bowel by the colonoscope is 1 in 3,000.  Risk of damage or bleeding during removal of a polyp is 1 in 500.  There is no radiation with colonoscopy although some physicians occasionally take simple x-rays to determine the position of the scope if they are having difficulty.

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