The large intestine, or colon, has four sections:
ascending colon - extends upward on the right side of the abdomen
transverse colon - extends from the ascending colon across the body to the left side
descending colon - extends from the transverse colon downward on the left side
sigmoid colon - named because of its S-shape; extends from the descending colon to the rectum
The rectum joins the anus, or the opening where waste matter passes out of the body.
Colorectal cancer screening guidelines for early detection from the American Cancer Society recommend that beginning at age 50, both men and women should follow one of the examination schedules below:
Persons with any of the following colorectal cancer risk factors should begin screening procedures at an earlier age and be screened more often:
A colonoscopy may be used to examine colon polyps, tumors, ulceration, inflammation, diverticula (pouches), strictures (narrowing), and foreign objects within the colon. It may also be used to determine the cause of unexplained chronic diarrhea or gastrointestinal bleeding or to evaluate the colon after cancer treatment.
Colonoscopy may be indicated when the results of a barium enema and/or sigmoidoscopy warrant further examination of the colon.
There may be other reasons for your physician to recommend a colonoscopy.
As with any invasive procedure, complications may occur. Complications related to colonoscopy include, but are not limited to, the following:
If you are pregnant or suspect that you may be pregnant, you should notify your physician.
There may be other risks depending upon your specific medical condition. Be sure to discuss any concerns with your physician prior to the procedure.
Certain factors or conditions may interfere with a colonoscopy. These factors include, but are not limited to, the following:
Your physician will explain the procedure to you and offer you the opportunity to ask any questions that you might have about the procedure.
You will be asked to sign a consent form that gives your permission to do the test. Read the form carefully and ask questions if something is not clear.
You will be asked to fast for eight hours before the procedure, generally after midnight. You may be given additional instructions about a special diet for one to two days prior to the procedure.
If you are pregnant or suspect that you are pregnant, you should notify your physician.
Notify your physician if you are sensitive to or are allergic to any medications, latex, tape, and anesthetic agents (local and general).
Notify your physician of all medications (prescribed and over-the-counter) and herbal supplements that you are taking.
Notify your physician if you have a history of bleeding disorders or if you are taking any anticoagulant (blood-thinning) medications, aspirin, ibuprofen, or other medications that affect blood clotting. It may be necessary for you to stop these medications prior to the procedure.
Your physician will instruct you about specific ways to prepare your bowel for the test. You may be asked to take a laxative, undergo an enema, use a rectal laxative suppository, and/or drink a special fluid that helps prepare your bowel.
Patients with diseases of the heart valves may be given antibiotics before the procedure.
A sedative and pain medication will be given to provide relaxation and drowsiness before the procedure. You will need someone to drive you home afterward.
Based upon your medical condition, your physician may request other specific preparation.
A colonoscopy may be performed on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your physician's practices.
Generally, the colonoscopy follows this process:
After the procedure, you will be taken to the recovery room for observation. Your recovery process will vary depending upon the type of sedation that is given. Once your blood pressure, pulse, and breathing are stable and you are alert, you will be taken to your hospital room or discharged to your home. Colonoscopy is usually done on an outpatient basis.
You may be asked to fast for a few hours and avoid foods high in fiber content for the first 24 hours after the procedure.
You may experience flatulence (passing of gas) and gas pains after the procedure. This is normal. Walking and moving about may help to ease any discomfort.
The first bowel movement after a colonoscopy may contain dark red or maroon-colored blood clots.
Alcohol should be avoided for at least 24 hours after sedation. You may be encouraged to drink extra fluids to make up for the water lost during preparation for the procedure.
Notify your physician about any of the following:
Following a colonoscopy, your physician may give you additional or alternate instructions after the procedure, depending on your particular situation.
You will not be able to drive following the procedure, so plan on having someone with you to take you home.
The content provided here is for informational purposes only, and was not designed to diagnose or treat a health problem or disease, or replace the professional medical advice you receive from your physician. Please consult your physician with any questions or concerns you may have regarding your condition.
This page contains links to other Web sites with information about this procedure and related health conditions. We hope you find these sites helpful, but please remember we do not control or endorse the information presented on these Web sites, nor do these sites endorse the information contained here.
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