We believe that preventing colorectal cancer (and not just finding it early) should be a major reason for getting tested. Finding and removing polyps keeps some people from getting colorectal cancer.
The American Cancer Society “Guidelines for the Early Detection of Cancer” recommend, beginning at age 50, both men and women at average risk for developing colorectal cancer should use one of the screening tests below:
Colonoscopy every 10 years
Flexible sigmoidoscopy every 5 years*
Double-contrast barium enema every 5 years*
CT colonography (virtual colonoscopy) every 5 years*
*Colonoscopy should be done if test results are positive
People at increased or high risk
If you are at an increased or high risk of colorectal cancer, you should begin colorectal cancer screening before age 50 and/or be screened more often. The following conditions make your risk higher than average:
A personal history of colorectal cancer or adenomatous polyps
A personal history of inflammatory bowel disease (ulcerative colitis or Crohn’s disease)
A strong family history of colorectal cancer or polyps
A known family history of a hereditary colorectal cancer syndrome such as familial adenomatous polyposis (FAP) or hereditary non-polyposis colon cancer (HNPCC)
The colon must be free of solid matter for the test to be performed properly. The day prior to the procedure, the patient is required to follow a clear-liquid only diet. Examples of clear fluids are jello, fruit juices (without pulp, ex. apple, white grape juice), sports drinks (Gatorade, Power Aid, etc.), water, beef and/or chicken broth/Bouillon, popsicles, tea (no milk/cream), or coffee (no milk/cream). It is very important that the patient remain hydrated. The patient should avoid liquids with red or purple dyes.
The day before the colonoscopy, the patient also starts their bowel preparation (typically Suprep or Golytely/Nulytely). Suprep is the most common bowel prep that we use. The patient drinks the 16 oz. solution at 6 pm the night prior to their procedure followed by 2 more 16 oz. containers of water. The morning of the procedure they drink another 16 oz. solution of Suprep followed by water. The timing of the morning dose depends on the time of your colonoscopy.
Since the goal of the preparation is to clear the colon of solid matter, the patient should plan to spend the day at home in comfortable surroundings with ready access to toilet facilities. A soothing salve such as petroleum jelly applied after cleaning the anus will improve patient comfort.
We also ask patients to skip aspirin or aspirin-like medications (Excedrin, Ibuprofen, Advil, Aleve, Motrin, Fish oil, Vitamin E, or Any blood thinner) one week prior to the procedure to avoid the risk of bleeding if a polypectomy is performed during the procedure.
During colonoscopy, patients lie on their left side on an examination table. During the procedure the patient is given sedation intravenously, employing agents such as fentanyl and midazolam. The average person will receive a combination of these two drugs. Deeper sedation may be required in some cases. The doctor and medical staff monitor vital signs and attempt to make patients as comfortable as possible.
The first step is usually a digital rectal examination, to examine the tone of the sphincter, to determine if the preparation has been adequate, and to perform a prostate examination. The doctor inserts a long, flexible, lighted tube called a colonoscope, or scope, into the anus and slowly guides it through the rectum and into the colon. The bowel is insufflated with air or carbon dioxode to maximize visibility. A small camera mounted on the scope transmits a video image from inside the large intestine to a computer screen, allowing the doctor to carefully examine the intestinal lining. The doctor may ask the patient to move periodically so the scope can be adjusted for better viewing.
Once the scope has reached the opening to the small intestine, it is slowly withdrawn and the lining of the large intestine is carefully examined again. Bleeding and puncture of the large intestine are possible but uncommon complications of colonoscopy.
An advantage of colonoscopy over less invasive tests, is the ability to perform therapeutic interventions during the test. A polyp is a growth of excess of tissue that can develop into cancer. Polyps are common in adults and are usually harmless. However, most colorectal cancer begins as a polyp, so removing polyps early is an effective way to prevent cancer. If a polyp is found, it can be removed by one of several techniques (a snare device, cautery, and/or biopsy forceps).
The doctor can also take samples from abnormal-looking tissues during colonoscopy. The procedure, called a biopsy, allows the doctor to later look at the tissue with a microscope for signs of disease.
On average, the procedure takes 30–60 minutes, depending on the indication and findings. With multiple polypectomies or biopsies, procedure times may be longer.
Cramping or bloating may occur after the procedure. The sedative takes time to completely wear off. Typically patients spend about 30-60 minutes in the recovery area prior to going home. Full recovery is expected by the next day. Discharge instructions should be carefully read and followed. We require that patients have a person with them to help them home afterwards. Driving is not permitted for 24 hours after colonoscopy to allow the sedative time to wear off.