What is a Colonoscopy?

A colonoscopy is performed to examine the colon (also known as the large intestine or bowel) and the rectum. Referrals for colonoscopies are made to detect any abnormalities or conditions of the colon. As a result, colonoscopies can save lives by diagnosing and identifying diseases before they become severe or even fatal. This procedure is typically performed by gastroenterologists who specialise in the gastrointestinal system (including the stomach, intestines, liver, etc.). A camera is attached to the end of a long and flexible tube called a colonoscope to observe inside the stomach.

What does a Colonoscopy Detect?

In Australia, one of the most common reasons for undergoing a colonoscopy is to screen for bowel cancer (also known as colorectal cancer). According to the Australian Institute of Health and Welfare statistics, this condition is the 4th most common and the 2nd most deadly cancer in the country. GPs will typically refer those at increased risk of developing bowel cancer or experiencing relevant symptoms to undergo a colonoscopy test. Additionally, colonoscopies may also detect:

Pre-Cancerous Colon polyps
Diverticulitis
Crohn's Disease
Ulcerative Colitis

When is a Colonoscopy Recommended?

Colonoscopies are general recommended by GPs for several reasons, including:

The presence of blood in your poo which can either be obvious to the naked eye or can be detected in small amounts not seen by the naked eye via a stool test
Persistent abdominal pain and cramps
Bleeding from the anus, especially after emptying into a toilet
Experiencing a change to your normal bowel habit
Having a high risk of developing bowel cancer (e.g. symptoms, family and past history of this condition, etc.)
Further investigations required by gastroenterologists or other specialists

Colonoscopy vs. Endoscopy

Both colonoscopies and endoscopies help detect abnormalities within the body. At the end of each instrument is a camera that visually shows the doctor what is occurring within the body. As noted above, the colonoscopy enters from the rectum before entering the large intestine and colon. On the other hand, an endoscopy is inserted into the throat before entering stomach, oesophagus and small intestine. A capsule endoscopy can also be performed by ingesting a small capsule which contains a mini camera.

Colonoscopy Procedure

Generally, 3 stages need to be followed during a colonoscopy, which includes:

Colonoscopy Prep / Preparation

Before the procedure, you will need to undergo the process of preparing the bowel. Different hospitals and specialists will recommend different preparation protocols. It's advised to read your preparation instructions at least two weeks earlier to ensure a successful colonoscopy. Certain dietary changes and medications may be prescribed to ensure that the bowel is emptied for inspection. There may also be a period where food and certain liquids need to be avoided before the procedure. Additionally, laxatives may also be prescribed to ensure that the bowel has been cleared.

Foods to avoid before colonoscopy procedure

Guidance about what to eat before colonoscopy will be provided before the procedure. Easily digestible foods should be prioritised at least a few days beforehand. For example, white bread, dairy and refined cereals are encouraged as opposed to foods that are harder to break down, such as nuts, whole grains and raw fruit or vegetables. Solid foods should be avoided on the day before the colonoscopy. Opting for liquid options, such as broths, fruit juices and popsicles are advised. On the day of the surgery, only clear liquids should be consumed to keep hydrated. More specific instructions may be provided depending on your gastroenterologist's preferences and your requirements.

During the Colonoscopy

During the procedure, in most cases, you will be sedated and asleep. This is to ensure that the procedure is as seamless and pain-free as possible. You will be required to lie on your left side with the knees tucked into the chest for this assessment. The long-tubular colonoscopy will enter the large intestine through the rectum. As the colonoscope enters the bowel, the operator will direct the camera inside the colon to inspect for any abnormalities.

How Long Does A Colonoscopy Take?

Typically the procedure itself will only take roughly 20-30 minutes.

After the colonoscopy

After the procedure, you may be required to stay on-site as the sedatives wear off. Initially, you may begin to feel some discomfort, cramping and bloating in the abdomen. As you regain consciousness, the doctor will briefly go over the colonoscopy's findings and whether further investigations are required. A follow-up with your doctor may be scheduled to interpret the results. Most people will recover quickly and be able to return home on the day of the procedure. However, there may be some residual discomfort and grogginess. Consequently, it may be more convenient and safer to arrange a ride home through family, friends or a taxi. Does a Colonoscopy Hurt? Generally, it's uncommon to experience noticeable pain after colonoscopy assessments. The colon does not have pain receptors and consequently will unlikely experience pain afterwards (even after removing polyps and biopsies). Air may be used to inflate the colon during the procedure, so there may be some temporary discomfort and bloating.

Colonoscopy Risks

Colonoscopies are generally well tolerated and safe procedures. However, there are some risks associated with this procedure and should only be performed when necessary. Examples of these risks include:

- Diverticulitis - inflammation and/or infection of the colon
- Perforation and internal bleeding
- Adverse reaction to the anaesthetic and/or sedatives
- Infections, such as E.Coli
- Dehydration during the preparation phase due to dietary changes.
- Abdominal pain

What is Colonoscopy? Examination of the Colon