A colonoscopy may be performed to screen for colon cancer and evaluate many problems, including:
In order to have a successful view of the interior of the colon, it must be completely cleaned. To prepare for the test, your physician will prescribe dietary, medication and social behavior modifications.
What is a colonoscopy?
A Colonoscopy is typically an outpatient procedure that allows your physician to examine the inside of the colon (large intestine or large bowel) and rectum. Your gastroenterologist may perform the procedure to diagnose and treat, when possible, certain diseases of the lower gastrointestinal (GI) tract, including the rectum and colon. During a colonoscopy, your physician uses a Colonoscope, also called an Endoscope, which is a long, flexible, tubular instrument that is about the width of an average pea, that transmits an image of the lining of the colon on a viewing monitor so the physician can examine it for any abnormalities. The Colonoscope is inserted through the rectum and advanced to the other end of the large intestine. (see diagram below)
You will be asked to stop any prescribed blood thinners five (5) days before your procedure. Acetaminophen (Tylenol) may be continued or used as a pain reliever. You will also be asked limit or eliminate high fiber foods for at least two (2) days before your procedure, including: salads, nuts or seeds of any kind, and any food with a peel or skin (examples include: popcorn, peanuts, fennel seeds, poppy seeds, sesame seeds, grapes, beans, tomatoes, green peas, corn, blueberries, raspberries, watermelon etc). Additionally, you will be required to adhere to a full "clear" liquid diet on the day before your procedure. We will cover the restrictions of a full "clear" liquid diet in the prep section of this site. There are several colonoscopy preparation medications that your doctor may prescribe, and each come with detailed instructions about the cleanse preparation. Whatever method of preparation is prescribed, you should follow the instructions given by your physician or their assistant, exactly as given, or the procedure could be unsuccessful and may have to be repeated. If your physician or his assistant has notified you that blood work is required, please complete at least 2 days prior to your procedure. You will also be advised to refrain from smoking, especially on the day of your procedure. The longer you refrain from smoking, the greater your chances are of avoiding anesthesia-related complications.
How long does a colonoscopy take?
A Colonoscopy can take anywhere from 15 minutes to an hour.
During the Procedure
If you have not already done so, you will have an opportunity to discuss this procedure with your physician or nurse. You will be asked if you are allergic to any medications. At this time, if applicable, also inform the nurse if there is a possibility of pregnancy. Prior to the procedure, you will be taken on a hospital bed into the endoscopy suite (procedure room) and connected to the vital monitoring devices to measure heart rhythm and blood pressure as well as oxygen in the blood. You will be asked to turn onto your left side and bend your knees slightly. Once you are comfortable, anesthesia (sedation) is administered through an intravenous line by the Anesthesiologist.
When you are properly relaxed, the colonoscope will be inserted into the rectum and advanced through your colon (large intestine) (see diagram). Once your physician has reached the Cecum (the tip of the colon or the last portion of the small intestine), a photo is taken of the Cecum and the colonoscope is slowly withdrawn while the lining of your bowel is carefully examined. During the withdrawal process, if the physician identifies any tissue that may be abnormal, a small amount of the tissue can be removed for microscopic analysis (this is called a biopsy) and abnormal growths, or polyps, can be identified and removed (this technique is referred to as a polypectomy). Biopsy and/or polypectomy specimens are sent to the laboratory for examination by a Pathologist. Results are typically available within 7-10 business days and you will be notified either by phone with the findings or by an email instructing you to visit the patient portal for a copy of your results.
After the Procedure
After your procedure, your vitals will be monitored and you will be cared for in a recovery area until most of the effects of the sedation have worn off. At this time, your physician will inform you, or a family member, about the results of your procedure and will provide any additional information you need to know. You may experience light abdominal cramping, bloating, and gas after your procedure. These symptoms should disappear within 24 hours or less. You MUST have someone to drive you home, as the medication given for sedation will not allow you to drive for 12 hours. Due to the effects of the sedation, you are advised:
Not to return to work for the remainder of the day of your procedure
Not to operate any machinery (for 12-24 hours)
Not to drink alcohol (for 12-24 hours)
The answer to this question depends on your risk factors for developing Colorectal Cancer. If you are 50 years or older, with no personal or family history of polyps or cancer, then your first colonoscopy should be at age 50. For African Americans, you should begin screening for colorectal cancer at age 45. If your initial colonoscopy is normal, you should repeat the procedure every 10 years until at least the age of 75. If you or one of your first degree relatives (parent, sibling or child) has or has previously had colorectal cancer or polyps, your risk for developing colorectal cancer increases. When this is the case, you may need to begin screening at an earlier age and you will need to repeat the procedure more frequently, depending on how prevalent your personal or family history is. The average risk of colorectal cancer in the US is about 6%. That means 6 out of every 100 people are at risk of developing colorectal cancer in their lifetime. If you have a parent with colorectal cancer over age 50, your own risk increases from 6% to about 15%. If that parent was younger than 50 when they were diagnosed, your risk increases to around 24%. If you have two (2) relatives with colorectal cancer, for example, an aunt and one of your parents, your risk is around 24%. The younger that the relative is affected, the higher your risk and the earlier you should begin colonoscopy screening. If you have had colon cancer previously, you should repeat your colonoscopy every 2-3 years. If you have had precancerous polyps removed from your colon previously, you will require regular surveillance colonoscopies, the frequency is determined by the number and size of the polyps removed. Other risk factors for increased colonoscopy intervals include, inflammatory bowel disease (IBD - Crohn's or Ulcerative Colitis), genetic or hereditary syndromes including, Lynch Syndrome, Hereditary Nonpolyposis Colorectal Cancer and Familial Adenomatous Polyposis (FAP).