Colonoscopy is a safe, minimally-invasive procedure used to examine the entire length of the colon (or large intestine) using a camera-mounted flexible tube inserted through the anus. It is capable of detecting very small lesions or abnormalities (less than 5mm in diameter) and allows the examiner to sample suspect tissue for biopsy as well as remove polyps or growths. Still photos are also captured and saved for use in diagnosis.
It is commonly used to screen for colon polyps and colon cancer, and can also employed to investigate gastrointestinal bleeding, unexplained anemia, persistent diarrhea, inflammatory bowel diseases (such as colitis or Crohn’s), abdominal pain, blood in the stool, or abnormalities found on a colon x-ray or CAT scan.
People who have had previous incidence of colon polyps or cancer, a family history of colon cancer, or who are 50 years of age or older should consult with their physician to discuss an appropriate schedule for regular colonscopies as an aid in early diagnosis.
Complications of the procedure are generally limited to perforation (a puncture or small hole) as well as bleeding and/or infection if a biopsy is performed, all of which are very rare. Reaction to the sedatives or medication used is also a possibility, so it is important to discuss your prior medical history with your doctor.
What to Expect
The colon must be completely empty in order to get clear and accurate results. This usually involves ingesting only liquids for one to three days prior to the procedure and may include enemas, laxatives, or a bowel irrigation. You will also need to discontinue some medications such as aspirin, blood thinners, insulin, arthritis medication, and iron supplements. Inform your doctor of your medical history, current medications, and any allergies (especially to pain medications and antibiotics). You will be given specific instructions before your scheduled test which must be followed exactly; see “Colonoscopy Preparation” below for more information.
Prior to the start of the procedure, an IV will be started for sedative and pain medicine; this will make you feel relaxed and drowsy. A monitor will also be set up to observe you vital signs. You will lie on your left side with your knees drawn up to your chest. After a rectal exam to check for blockages, the colonoscope is gradually inserted through the anus into your colon. When the end of the scope reaches the start of your small bowel, it will slowly be drawn back through. Generally, it is easier to examine the colon as the scope is being withdrawn so this portion of the exam may go slower. During the exam, air may be blown into the colon to improve the camera’s view. The entire procedure will last anywhere from 15 minutes to an hour.
When the colonoscopy is over, you will be monitored as the effects of any medications you were given wear off. Side effects may include cramping or a bloated feeling, both of which are mild and are usually relieved by passing gas. You will be required to have someone else drive you home from the test. Generally you can resume eating right away, but if you have had any polyps or tissue removed for biopsy, your doctor might want you to follow a restricted diet for a few days.
Colonoscopy preparation using Colyte (GoLytely or NuLytely)
Please follow these instructions to the letter. If you have any questions about these directions, talk to your doctor beforehand.
The day before your colonoscopy
Breakfast: Enjoy a light breakfast which can include coffee, eggs, white bread, juice, or low-fiber cereal (such as rice krispies). Do not have oatmeal. One 8-ounce can of Ensure or Boost is suggested as well, but do not take Ensure Plus or Boost with Fiber.
In the morning, mix the Colyte (GoLytely or Nulytely) with the accompanying flavor packs according to the instructions. Do not refrigerate.
Lunch: This meal can same foods as breakfast as well as liquids as you desire. Appropriate liquids include jello, popsicles, Italian ice, soup (only clear soup without vegetables or noodles; plain chicken broth is fine), soda, Gatorade, coffee, tea, water, and juices (with no pulp). You can have any liquid through which you can see light along with a very light meal. Make sure none of the liquids are red or purple in color.
For the rest of the day you should consume liquids only (as described above). You will need to ingest 8 ounces of clear liquid at 2:00 pm, 3:00 pm, and 4:00 pm.
At 6:00 pm, start drinking the Colyte (GoLytely or NuLytely), in increments of one glass (8 ounces) every 10 minutes. It is best to drink the whole glass rapidly, rather than sipping small amounts continuously. You may refrigerate it at this point, or add ice to the glass if it makes it taste better. If necessary, you can take 2 to 3 hours to finish, but CONTINUE DRINKING UNTIL THE BOTTLE IS EMPTY.
Feelings of bloating and/or nausea are common after the first few glasses of Colyte (GoLytely or NuLytely) because of the large volume of fluid ingested. This is temporary, however, and will disappear once bowel movements begin.
Bowel movements should occur about one hour after the first glass of Colyte (GoLytely or NuLytely) is ingested. They will continue periodically for approximately 1-2 hours after you finish drinking the last glass. By this time, the stool liquid should be clear. You may drink as much water as you like until midnight.
After midnight, you should not drink anything else. You may take medications if they have been approved by the doctor. Aspirin, Motrin, Nuprin, Advil, Alka-Seltzer, and vitamin E should be discontinued five days prior to the procedure. Tylenol is permitted.