Your doctor has ordered an endoscopic examination of your large intestines, or colon. During this procedure, a flexible tube (colonoscope) is passed through the rectum and advanced through the colon. The instrument lets the doctor view the lining of the colon. Photographs may also be taken. The instrument also allows for the biopsy of colon tissue or the removal of growths (polyps). A biopsy is taken for many reasons and does not necessarily mean that cancer is suspected.
Preparing for the procedure
It is important that you have nothing to eat for approximately six hours before the examination or as directed by your physician; you may have clear beverages only up to two hours before the procedure.
Proper cleansing of the colon is essential to give a clear view. Several methods are available. Your doctor will decide which one is best for you. If you are not able to finish your preparation as instructed, please call your doctor.
On the day of the procedure
All patients having a colonoscopy must bring one responsible companion. This person will stay in the waiting room and drive you home. If you cannot arrange for a companion, the procedure may need to be rescheduled.
A nurse will bring you to the pre-procedure area to take your blood pressure and pulse rate, ask questions about your medical history, including any allergies to medications, and answer any questions you may have. You will be asked to remove your clothing and put on a hospital gown. Please read the consent form and sign it. This authorizes the doctor to perform the procedure.
An intravenous line, or IV, will be inserted now for medicines that are often given during the procedure. These will include sedatives that will help you feel comfortable and relaxed.
You will be moved to a procedure room. Usually a colonoscopy is done with the patient on the left side. Your vital signs will be checked throughout the procedure and oxygen will be administered.
A colonoscopy is usually well tolerated and rarely causes much pain. The lubricated flexible colonoscope will be gently introduced into your rectum. It may cause feelings of pressure, bloating or cramping during the procedure. This is due to air inserted into the colon through the instrument. To ease the passage of the colonoscope, you may need to change position or have gentle pressure applied to your abdomen. A biopsy (sample of the colon lining) may be taken for microscopic examination. Colon polyps can be biopsied or removed entirely. You will not feel any sensation or discomfort during a biopsy or polyp removal.
The examination usually takes 20 to 40 minutes.
After the procedure
After the colonoscopy, you will be taken to the recovery area to rest until most of the sedative has worn off, usually 30 to 45 minutes. A bloating sensation is normal and will disappear quickly with the passage of gas.
Because you may still feel drowsy by the end of the procedure, the doctor may wait to explain the findings to you. The doctor may discuss the results of your test with your companion unless instructed otherwise. Before you go home, you will receive written instructions about caring for yourself.
Endoscopy is safe. Many people do not even recall the procedure because of the sedatives. Complications during a colonoscopy are very rare. The major potential complications are perforation (tear in the intestinal lining) or bleeding which may rarely require either blood transfusion or surgery. Other possible risks include a reaction to the sedatives and complications from heart or lung disease. The vein where the medicine was injected may be irritated. This can cause a tender lump that should go away within a few days.
Colorectal cancer is the third leading cause of cancer death in both men and women in the United States. Because many people experience no symptoms during the early stages, early detection through regular screenings is the best way to improve the chance of successful treatment. Anyone who is 50 or older or has a family history of colon cancer could be at risk.