Colonoscopy is a procedure that enables your surgeon to examine the lining of the colon and rectum. It is usually done in the hospital or an endoscopic procedure room on an outpatient basis. A soft, bendable tube about the thickness of the index finger is gently inserted into the anus and advanced into the rectum and the colon.
Why is a Colonoscopy performed?
A colonoscopy is usually done
- as part of a routine screening for cancer,
- in patients with known polyps or previous polyp removal,
- before or after some surgeries,
- to evaluate a change in bowel habits or bleeding or
- to evaluate changes in the lining of the colon known as inflammatory disorders.
What preparation is required?
The rectum and colon must be completely emptied of stool for the procedure to be performed. In general, preparation consists of consumption of Prepkit C. This pack contains 1 sachet of Glycoprep and 2 sachets of Picoprep.
Your surgeon and his staff will provide you with instructions regarding the cleansing routine necessary for the colonoscopy.
Follow your surgeon’s instructions carefully. If you do not complete the preparation, it may be unsafe to perform the colonoscopy and the procedure may have to be rescheduled. If you are unable to take the preparation, contact your surgeon.
Most medications can be continued as usual. Medication use such as aspirin, Vitamin E, non-steroidal anti-inflammatories, blood thinners and insulin should be discussed with your surgeon prior to the examination as well as any other medications you might be taking. It is essential that you alert your surgeon if you require antibiotics prior to undergoing dental procedures, since you may also require antibiotics prior to colonoscopy.
You will most likely be sedated during the procedure and an arrangement to have someone drive you home afterward is imperative. Sedatives will affect your judgment and reflexes for the rest of the day. You should not drive or operate machinery until the next day.
What can be expected during a Colonoscopy?
The procedure is usually well tolerated, but there is often a feeling of pressure, gassiness, bloating or cramping at various times during the procedure. Your surgeon will give you medication through a vein to help you relax and better tolerate any discomfort that you may experience. You will be lying of your side or your back while the colonoscope is advanced through the large intestine. The lining of the colon is examined carefully while inserting and withdrawing the instrument. The procedure usually lasts for 15 to 60 minutes. In rare instances the entire colon cannot be visualized and your surgeon may request an additional test such as a barium enema or a CT colonography.
What if Colonoscopy shows an abnormality?
If your surgeon sees an area that needs more detailed evaluation, a biopsy may be obtained and submitted to a laboratory for analysis. A biopsy is performed by placing a special instrument through the colonoscope. Most polyps can be removed at the time of the colonoscopy. The majority of polyps are benign (non-cancerous), but your surgeon cannot always tell by the appearance alone. They can be removed by burning (fulgurating) or by a wire loop (snare).
It may take your surgeon more than one sitting to do this if there are numerous polyps or if the polyps are very large. Sites of bleeding can be identified and controlled by injecting certain medications or coagulating (burning) the bleeding vessels. Biopsies do not imply cancer, however, removal of a colonic polyp is an important means of preventing colon and rectal cancer.
What happens after Colonoscopy?
Your surgeon will explain the results to you after your procedure or at your follow up visit. You may have some mild cramping or bloating from the air that was placed into the colon during the examination. This should quickly improve with the passage of the gas. You should be able to eat normally the same day and resume your normal activities after leaving the hospital. Do not drive or operate machinery until the next day, as the sedatives given will impair your reflexes.
If you have been given medication during the procedure, you will be observed until most of the effects of the sedation have worn off (1-2 hours). You will need someone to drive you home after the procedure. If you do not remember what your surgeon told you about the examination or follow up instructions. Call your surgeon’s office that day or the next to find out what you were supposed to do.
If polyps were found during your procedure, you will need to have a repeat colonoscopy. Your surgeon will decide on the frequency of your colonoscopy exams.
If the surgeon finds haemorrhoids or piles during the procedure he will also band them with rubber bands during the procedure. The ischaemic haemorrhoid will then slough off after a period of time.
What complications can occur?
Colonoscopy complications include bleeding from the site of a biopsy or polypectomy and a tear (perforation) through the lining of the bowel wall. The risk of a perforation is 1:1000. Other complications of the procedure include the possibility of missed polyps or other lesions.
Should a perforation occur, it may be necessary for your surgeon to perform abdominal surgery to repair the intestinal tear. Blood transfusions are rarely required. A reaction to the sedatives can occur. Irritation to the vein that medications were given is uncommon, but may cause a tender lump lasting a few weeks. Warm, moist towels will help relieve this discomfort.
It is important to contact your surgeon if you notice symptoms of severe abdominal pain, fevers, chills or rectal bleeding of more than one-half cup. Bleeding can occur up to several days after a biopsy.