The Basics of Colonoscopy
How Is a Colonoscopy Performed?
The colonoscopy should be performed by an experienced doctor and last approximately 30-60 minutes. You will receive medication to make you feel relaxed. You will be asked to lie on your left side on the examining table. During a colonoscopy, the doctor uses a colonoscope, a long, flexible, tubular instrument about 1/2 inch in diameter that transmits an image of the lining of the colon on a screen so the doctor can examine it for any abnormalities. The colonoscope is inserted through the rectum and advanced to the other end of the large intestine.
The scope bends, so the doctor can move it around the curves of your colon. You may be asked to change position occasionally to help the doctor move the scope. The scope also blows air into your colon, which expands the colon and helps the doctor to see.
You may feel mild cramping during the procedure. You can reduce the cramping by taking several slow, deep breaths during the procedure. When the doctor has finished, the colonoscope is slowly withdrawn while the lining of your bowel is carefully examined.
During the colonoscopy, if the doctor sees something that may be abnormal, small amounts of tissue can be removed for analysis (called a biopsy) and abnormal growths, or polyps, can be identified and removed. In many cases, colonoscopy allows accurate diagnosis and treatment without the need for a major operation.
What Happens After a Colonoscopy?
After you have a colonoscopy:
- You will stay in a recovery room for about 30 minutes for observation.
- You may feel some cramping or a sensation of having gas, but this usually passes quickly.
- You will need to have someone drive you home, as it is unsafe to drive or operate machinery for about 8 hours after the procedure (due to the sedative medication given).
- You can resume your normal diet.
Read your discharge instructions carefully. Certain medications, such as blood-thinning agents, may need to be avoided temporarily if biopsies were taken or polyps were removed.
Warning About Colonoscopy
Bleeding and puncture of the colon are rare but possible complications of colonoscopy. Call your doctor right away if you have: