Colonoscopy Health Article

Preparation

The doctor should be notified if the patient has allergies to any medications or anesthetics, has any bleeding problems, or if a female patient is pregnant. The doctor should also be informed of all the medications that the patient is currently taking and if he or she has had a barium x-ray examination recently. The doctor may instruct the patient not to take certain medications, like aspirin and anti-inflammatory drugs that interfere with clotting, for a period of time prior to the procedure. If the patient has had heart valves replaced or a history of an inflammation of the inside lining of the heart, the doctor should be informed, so that appropriate antibiotics can be administered to prevent any chance of infection. The risks of the procedure will be explained to the patient before performing the procedure and the patient will be asked to sign a consent form.

It is important that the colon be thoroughly cleaned before performing the examination. Hence, before the examination, considerable preparation is necessary to clear the colon of all stool. The patient will be asked to refrain from eating any solid food for 24-48 hours before the test. Only clear liquids such as juices, broth, and gelatin are recommended. The patient is advised to drink plenty of water to avoid dehydration.

The day before the test, the patient will have to drink a special cleansing solution or take a strong laxative that the doctor has prescribed. The patient will also be given specific instructions as to how to use an enema, as a warm water enema may be necessary the next morning.

On the morning of the examination, one or two enemas of warm tap water may have to be taken. Generally, the procedure has to be repeated until the return from the enema is clear of stool particles. The patient is instructed not to eat or drink anything. The preparatory procedures are extremely important because the colon must be thoroughly clean for the exam to be performed.

Aftercare

After the procedure, the patient is kept under observation until the effects of the medications wear off. The patient will not be able to drive immediately after the procedure and can generally resume a normal diet and usual activities unless otherwise instructed. The patient will be advised to drink lots of fluids to replace those lost by laxatives and fasting.

For a few hours after the procedure, the patient may feel groggy. There may be some abdominal cramping and a considerable amount of gas may be passed. If a biopsy was performed or a polyp was removed, there may be small amounts of blood in the stool for a few days. If the patient experiences severe abdominal pain or has persistent and heavy bleeding, it should be brought to the doctor's attention immediately.

Risks

The procedure is considered safe. Very rarely (2 in 1, 000 cases) there may be a perforation (a hole) in the intestinal wall. Heavy bleeding due to the removal of the polyp or from the biopsy site occurs very infrequently (1 in 1, 000 cases). Infections due to a colonoscopy are also extremely rare. Patients with artificial or abnormal heart valves are usually given antibiotics before and after the procedure to prevent an infection.

Normal results

The results are said to be normal if the lining of the colon is a pale reddish pink and there are no abnormal looking masses that are found in the lining of the colon.

Abnormal results

Abnormal results would imply that polyps or other suspicious-looking masses were detected in the lining of the intestine. Polyps can be removed during the procedure and tissue samples can be biopsied. If cancerous cells are detected in the tissue samples, then a diagnosis of colon cancer is made. The pathologist analyzes the tumor cells further to estimate the aggressiveness of the tumor and the extent of spread of the disease.

Abnormal findings also could be due to inflammatory bowel diseases such as ulcerative colitis or Crohn's disease. A condition called diverticulosis, in which many small fingerlike pouches protrude from the colon wall, may also be identified.

Resources

BOOKS

Berkow, Robert et al., eds. Merck Manual of Diagnosis and Therapy, 17th edition. Rahway, NJ: Merck Publishing Group, 1999.

Fauci, Anthony S. "Gastrointestinal Endoscopy." In Harrison's Principles of Internal Medicine, 14th edition. New York, NY: The McGraw-Hill Companies, 2000.

Pfenninger, John L. Procedures for Primary Care Physicians, 2nd edition. St. Louis: Mosby, Inc. 2000.

Stauffer, Joseph and Joseph C. Segen. The Patient's Guide to Medical Tests. New York: Facts On File, 1997.

ORGANIZATIONS

American Cancer Society (National Headquarters). 1599Clifton Road, N.E. Atlanta, Georgia 30329. (800) 227-2345. <http://www.cancer.org>

American Gastroenterological Association. 7910 Woodmont Ave., Seventh Floor, Bethesda, MD 20814. Phone: (301) 654-2055. www.gastro.org.

Cancer Research Institute (National Headquarters). 681 Fifth Avenue, New York, N.Y. 10022. (800) 992-2623. <http://www.cancerresearch.org>

National Cancer Institute. 9000 Rockville Pike, Building 31, Room 10A31, Bethesda, Maryland, 20892. (800) 422-6237. <http://www.icic.nci.nih.gov>

Society of American Gastrointestinal Endoscopic Surgeons (SAGES). 2716 Ocean Park Boulevard, Suite 3000, Santa Monica, CA 90405. (310) 314-2404. <http://www.sages.org>

United Ostomy Association, Inc. (UOA). 19772 MacArthur Blvd., Suite 200, Irvine, CA 92612. (800) 826 0826. <http://www.uoa.org.>

Lata Cherath, Ph.D.