Colonoscopy is a procedure which enables a physician (usually a gastroenterologist) to directly image and examine the entire colon.
It is effective in the diagnosis and/or evaluation of various GI disorders (e.g. colon polyps, colon cancer, diverticulosis, inflammatory bowel disease, bleeding, change in bowel habits, abdominal pain, obstruction and abnormal x-rays or CT scans) as well as in providing therapy (for example, removal of polyps or control of bleeding). It is also used for screening for colon cancer. A key advantage of this technique is that it allows both imaging of abnormal findings and also therapy or removal of these lesions during the same examination. This procedure is particularly helpful for identification and removal of precancerous polyps.
Colonoscopy may be recommended as a screening test for colorectal cancer. Colorectal cancer is the second leading cause of cancer deaths in Australia. Annually, it is estimated that about 17,000 people in Australia are diagnosed with bowel cancer. In the United States, approximately 150,000 new cases of colorectal cancer are diagnosed each year and approximately 50,000 people die from the disease.
It has been estimated that increased awareness and screening through colonoscopy would save the lives of at least half of those patients each year.
About one in 19 men and one in 28 women will develop bowel cancer before the age of 75. It is most common in people over 50, but it can occur at any age.
Colonoscopy may also be recommended by your doctor to evaluate for symptoms such as bleeding and chronic diarrhoea.
Your doctor will tell you what dietary restrictions to follow and what cleansing routine to use. In general, the preparation consists of either consuming a large volume of a special cleansing solution or clear liquids and special oral laxatives. The colon must be completely clean for the procedure to be accurate and complete, so be sure to follow your doctor’s instructions carefully.
If you have any concerns or questions about your bowel preparation, please contact our nurse on (02) 9707-3523.
Most medications can be continued as usual, but some medications can interfere with the preparation or the examination. Inform your doctor about medications you’re taking, particularly aspirin products, arthritis medications, anticoagulants (blood thinners), insulin or iron products, and any vitamins. Also, be sure to mention allergies you have to medications.
Alert your doctor if you require antibiotics prior to dental procedures, because you might need antibiotics before a colonoscopy as well.
If you have any concerns or questions about managing your medications, please contact our nurse on (02) 9707-3523.
Colonoscopy is well-tolerated and rarely causes much pain. You might feel pressure, bloating or cramping during the procedure. Your doctor might give you a sedative to help you relax and better tolerate any discomfort.
You will lie on your side or back while your doctor slowly advances a colonoscope through your large intestine to examine the lining. Your doctor will examine the lining again as he or she slowly withdraws the colonoscope. The procedure itself usually takes 15 to 60 minutes, although you should plan on two to three hours for waiting, preparation and recovery.
In some cases, the doctor cannot pass the colonoscope through the entire colon to where it meets the small intestine. Although another examination might be needed, your doctor might decide that the limited examination is sufficient.
If your doctor thinks an area needs further evaluation, he or she might pass an instrument through the colonoscope to obtain a biopsy (a sample of the colon lining) to be analyzed. Biopsies are used to identify many conditions, and your doctor might order one even if he or she doesn’t suspect cancer. If colonoscopy is being performed to identify sites of bleeding, your doctor might control the bleeding through the colonoscope by injecting medications or by coagulation (sealing off bleeding vessels with heat treatment). Your doctor might also find polyps during colonoscopy, and he or she will most likely remove them during the examination. These procedures don’t usually cause any pain.
Polyps are abnormal growths in the colon lining that are usually benign (noncancerous). They vary in size from a tiny dot to several inches. Your doctor can’t always tell a benign polyp from a malignant (cancerous) polyp by its outer appearance, so he or she might send removed polyps for analysis. Because cancer begins in polyps, removing them is an important means of preventing colorectal cancer.
Your doctor might destroy tiny polyps by fulguration (burning) or by removing them with wire loops called snares or with biopsy instruments. Your doctor might use a technique called “snare polypectomy” to remove larger polyps. That technique involves passing a wire loop through the colonoscope and removing the polyp from the intestinal wall using an electrical current. You should feel no pain during the polypectomy.
Your physician will explain the results of the examination to you, although you’ll probably have to wait for the results of any biopsies performed.
If you have been given sedatives during the procedure, someone must drive you home and stay with you. Even if you feel alert after the procedure, your judgment and reflexes could be impaired for the rest of the day. You might have some cramping or bloating because of the air introduced into the colon during the examination. This should disappear quickly when you pass gas.
You should be able to eat after the examination, but your doctor might restrict your diet and activities, especially after polypectomy.
Colonoscopy and polypectomy are generally safe when performed by doctors who have been specially trained and are experienced in these procedures.
One possible complication is a perforation, or tear, through the bowel wall that could require surgery. Bleeding might occur at the site of biopsy or polypectomy, but it’s usually minor. Bleeding can stop on its own or be controlled through the colonoscope; it rarely requires follow-up treatment. Some patients might have a reaction to the sedatives or complications from heart or lung disease.
Although complications after colonoscopy are uncommon, it’s important to recognize early signs of possible complications. Contact your doctor if you notice severe abdominal pain, fever and chills, or rectal bleeding of more than one-half cup. Note that bleeding can occur several days after the procedure.