The What, Why and How of A Colonoscopy
Charles Barkley, former NBA star, was to have a televised colonoscopy as part of the upcoming "Stand Up to Cancer" event that will be simulcast on CBS, NBC and
Via Sports Media Watch, Dan Gross at the Philadelphia Daily News reported that Charles Barkley, former NBA star, was to have a televised colonoscopy as part of the upcoming "Stand Up to Cancer" event that will be simulcast on CBS, NBC and ABC, on 5 Sept 08. As I don’t live in the States and know NBA as much as my readers know about Tai-Chi, I have yet to find out whether the procedure or the broadcast actually took place. Nonetheless, the colonoscopy is relevant even to you. This article explains the what, why and how of a colonoscopy.
What is a colonoscopy?
A colonoscopy allows the surgeon or gastroenterologist to look inside the entire large bowel (includes cecum, colon and rectum). The procedure will help detect presence of inflamed tissue, abnormal growths, and ulcers. It is most often performed to screen for cancer in the colon and rectum. It is also used to investigate for causes of changes in bowel habits, abdominal pain, rectal bleeding, and weight loss.
What is the colon?
The colon, or large bowel, is the last portion of your digestive tract. The colon is an elastic muscular tube that starts at the end of the small intestine and ends at the rectum and anus. It is about 1.3m long. It helps the digestive tract is to store unabsorbed waste of food and absorb fluids before the waste is excreted as stool.
Bowel Preparation
You will be given instructions to explain what to do to prepare for your colonoscopy. Your colon must be completely empty for the colonoscopy to be safe and accurate. To prepare for the procedure you will have to follow a low residue diet on day 1 of your bowel preparation and then a liquid diet on day 2. Low residue diet means no fruit, vegetables, meat (with the exception of fish) is allowed. The liquid diet should be clear and not contain food colorings, and may include plain coffee, tea, juice, broth, and gelatin.
Thorough cleansing of the bowel is necessary on the night prior to the colonoscopy. You are asked to take a laxative to achieve this. While this laxative used to be 2 liters of a liquid, this has now been replaced by a 90cc volume of a laxative liquid. You have to inform your doctor about your medical conditions that require medications including aspirin, arthritis drugs, blood thinners, diabetic drugs and iron supplements. You also need to inform your doctor about your medical conditions including heart disease, lung disease, or any medical condition that may need special attention. You must also arrange for someone to accompany you home. Make sure you don’t drive or operate machines after being sedated for the procedure.
The Procedure
For the colonoscopy, you will lie on your left side on the examining table. You will be given an intravenous pain killer and a sedative to lessen your discomfort and apprehension. Your doctor and his staff will monitor your vital signs and make sure you are OK throughout the procedure.
The doctor will then insert a 2m long, bandable, tube (called a colonoscope) into your rectum. This is gently manipulated up to the top of your colon. The scope transmits the image inside your colon onto a video screen. Because of the sedative used, most patients do not remember the procedure afterwards.
Abnormal growths in your colon, including polyps are removed using tiny tools passed through the scope. Most polyps are benign (not cancerous). However, some of these, especially the larger ones, can turn into cancer. The polyps are sent for testing. By identifying and removing polyps, a colonoscopy prevents large bowel cancers from forming.
The doctor can also remove tissue samples to test in the lab for diseases of the colon (biopsy). In addition, if any bleeding occurs in the colon, the doctor can pass a laser, heater probe, electrical probe, or special medicines through the scope to stop the bleeding. The tissue removal and treatments to stop bleeding usually do not cause pain. In many cases, a colonoscopy allows for accurate diagnosis and treatment of colon abnormalities without the need for a major operation. Bleeding and puncture of the colon are possible but uncommon complications of a colonoscopy. A colonoscopy usually takes 30 to 60 minutes. Some cramping or bloating of the abdomen is common following the procedure. You will need to sleep off your sedation for 1 to 2 hours before you are allowed to go home.
The Post-operative Night
Rarely, symptoms including severe abdominal pain, fever, bleeding in stools, sweating and dizziness may occur afterward. Should these happen, contact your surgeon or gastroenterologist immediately. Most patients recover fully within one day to resume their usual activities.
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