The colonoscopy is one of the primary diagnosis and treatment tools for gastroenterologists when it comes to treating several health conditions. Here, a colonoscope is used which is a long, flexible, tubular instrument that transmits an image of the lining of the colon. This is so that medical professionals can examine it for any abnormalities.


The device is inserted through the rectum and guided through to the end of the large intestine.


Primarily used to detect bowel or colorectal cancer and for the detection and removal of bowel polyps, thousands of individuals in Australia undergo this procedure every year. This blog looks at the basic facts concerning the colonoscopy and patient preparatory information.


Preparation for a colonoscopy


Preparation time for a colonoscopy often begins as early as 7 days prior to the procedure. Careful preparation is necessary to ensure that the gut is as visible as possible for accurate diagnosis and treatment.


Bowel preparation guidelines may differ between each facility. The general process is that patients change their diet before the colonoscopy, avoiding high-fibre food items including brown rice, pasta, fruit, bran, cereals, nuts and seeds and anything else noted by the doctor.


Low-fibre items such as white rice, white bread, yoghurt, cheese, potato, and pumpkin may be recommended instead.

Patients will also be prescribed certain laxatives that need to be taken 12 to 18 hours before the colonoscopy. This helps clear the bowel, allowing gastroenterologists to get a clear view of the colon during the colonoscopy.

In certain cases, an enema may be used to clear the bowel. Here, a liquid that washes out the lower part of the bowel is inserted into the rectum. The matter is then passed into the toilet along with faeces.

In the last 12 to 24 hours before the procedure, patients are required to depend on fluids alone, including water, broth, black tea and coffee, and fruit juice without pulp.


Day of the procedure


On the day of the procedure, patients are asked to lie down on a bed after wearing a medical gown. After a standard consent form is signed, the IV is inserted into the arm for sedation. This is generally administered by professional anaesthetists.

The gastroenterology specialist will then carry out the colonoscopy, as explained to each patient and attempt to either diagnose or treat certain conditions.

Following the procedure, patients will be given food and asked to rest. Many are briefed about the results of the colonoscopy and given further medical advice on medication that can be resumed, provided patients were on medication before the procedure.

Patients will need to be driven home by a relative or friend, as it is dangerous to drive while recovering from the effects of an anaesthetic.

Post-procedure guidelines


After a colonoscopy procedure, patients may report grogginess for a few hours. Individuals under the effect of anaesthesia must refrain from driving, operating heavy machinery, and signing legal documents up to 24 hours after the colonoscopy.

Regular eating habits can be resumed, although patients are likely to experience temporary bloating and gas. If pain or bleeding is experienced, individuals must contact the hospital where the procedure was performed. If this takes place after hours, visiting an ER is necessary.


Alternative diagnostic tools


A virtual colonoscopy is where an MRI or CT scanner is used to create images of the colon and rectum and display them on a screen. This is also referred to as a CT colonography.

While this is an alternative diagnostic tool, a traditional colonoscopy is preferred because it is more accurate and allows for polyp removal and biopsy extraction. A virtual colonoscopy is performed in scenarios where a standard colonoscopy is not possible.


Experienced gastroenterology specialists are qualified to perform a colonoscopy procedure


The diagnosis and recovery relating to several gastroenterological conditions rest on the success of a colonoscopy procedure. Patients who have been asked to undergo this minor procedure must consult specialists with expert knowledge on conducting this exam and analysing the results.

Dr Suhirdan Vivekanandarajah is a trained interventional gastroenterology specialist and hepatologist in Sydney. For further information about a colonoscopy and to register for the procedure itself, individuals can visit his site.

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