Colonoscopy is advised for all average-risk patients, age 50 and older, as a method of colon cancer screening. The procedure is preformed using a colonoscope, a long flexible tube that permits visualization of the lining of the large bowel utilizing a video monitor. The instrument is inserted via the rectum and guided through the length of the colon. If the doctor sees a suspicious area, a biopsy can be done to make a diagnosis.
Reasons for Colonoscopy
Colonoscopy is a valuable tool for the diagnosis and treatment of many diseases of the large intestine. Indications for this procedure include:
- the detection and removal of polyps, surveillance for new polyps in individuals with a past history of polyps, or cancer of the colon.
- those at risk for the development of polyps or colon cancer (such as individuals with a family history of colon cancer).
- assessment of abnormalities of the large bowel detected on another study.
- rectal bleeding.
- changes in bowel habit.
- inflammatory bowel disease.
- therapeutic intervention such as in the setting of rectal bleeding, strictures of the colon, or abnormal lesions.
- distention of the large bowel.
- abdominal pain.
Age-appropriate patients not experiencing any of the above gastrointestinal issues may want to take advantage of our Open Access Colonoscopy program to schedule a colonoscopy procedure, usually without the need for a pre-procedure consultation.
Polyp Removal (polypectomy)
During the course of the examination, a polyp may be found. Polyps are abnormal growths of tissue which vary in size from a tiny dot to several inches. If your doctor feels that removal of the polyp is indicated, he will pass a wire loop or snare through the colonoscope and sever the attachment of the polyp from the intestinal wall by means of an electrical current. You should feel no pain during removal of the polyp. Polyps are usually removed because they can cause rectal bleeding, potentially grow larger and develop into cancerous growths, or contain cancer. Although the majority of polyps are benign (non-cancerous), a small percentage may contain an area of cancer in them or may develop into cancer. Removal of colon polyps is an important means of prevention and cure of colon cancer, which is the second leading cause of cancer death in the United States.
Preparation for the Procedure
Specific instructions will be provided to you regarding cleansing the bowel in anticipation of the colonoscopy examination. It is very important that the instructions be followed as outlined in order to ensure a well-prepared colon which will facilitate the colonoscopy.
Please bring a list of medications you currently take and dosage of these drugs, and inform your physicians of any allergies you have to medications. If you are taking aspirin, coumadin, or blood thinners, please notify your doctor as the use of these drugs may need to be modified or discontinued temporarily.
A companion must accompany you to the examination because you will be given medications to sedate you during the procedure. You will feel drowsy and consequently you will need someone to take you home since driving an automobile is not allowed after the procedure. Even though you may not feel tired, your judgment and reflexes may not be normal.
What to Expect During the Procedure
A small catheter for intravenous (IV) medicines will be placed in an arm vein prior to the procedure. Sedating medicine will be injected through this catheter that will make you relaxed and sleepy. For some patients, deep sedation, where the patient is completely asleep, is utilized for the procedure. You will be placed in a comfortable position on your left side and the doctor will examine the rectum gently with a lubricated, gloved finger. The colonoscope will then be placed into your rectum and advanced to permit examination of the colon. You may feel some cramping or gas from air that is introduced during the procedure, although air can be suctioned from the colon during the examination. There may also be some discomfort as the instrument negotiates turns or bends In the colon. You may be placed into a different position during the examination (such as on your back) in order to facilitate passage of the instrument through the entire large bowel. The nurse who assists the doctor during this procedure may also compress the abdomen with his or her hand in order to reduce looping of the colonoscope and facilitate passage of the instrument through the colon.
The examination usually takes approximately 30 minutes to complete, however, more or less time may be utilized depending upon the specific colon anatomy and whether biopsies, polyp removal, or specific intervention is indicated.
Recovery from Colonoscopy
You will be kept in the endoscopy recovery area until most of the effects of the medication have worn off (30 – 60 minutes). You may feel somewhat bloated after the examination because of air that was introduced to perform the examination. You will be able to resume your diet after the examination but you may receive special dietary guidelines based upon the findings of the colonoscopy or if a polyp is removed. The findings of the examination will be reviewed with you and additional recommendations, if necessary, will be discussed.
Risks of Colonoscopy
Colonoscopy and polypectomy are safe and are associated with very low risk. One possible complication is perforation in which a tear through the wall of the bowel may allow leakage of intestinal fluids. This complication usually requires surgery for treatment. Bleeding may occur from the site of biopsy or polyp removal. It is usually minor and stops on its own or can be controlled by cauterization (application of an electrical current) through the colonoscope. Rarely transfusions or surgery are required. Irritation of a vein at the site where medications were administered may also occur. Drug reactions may also occur despite careful review of an individual’s medical history. Finally, like any test, pathology may be missed in a small number of cases leading to an error in diagnosis.