Colonoscopy in Sydney

What a colonoscopy is

A colonoscopy is an examination of the whole large bowel with a flexible camera about the thickness of a finger, passed through the anus and around the colon. The bowel has to be empty for it to work, which is what the preparation is for.

The reason it is worth doing is that it is not only a camera. Anything suspicious that is found can usually be dealt with in the same sitting. Polyps are removed as they are found, biopsies are taken where needed, and larger or more difficult growths can often be taken out endoscopically rather than surgically.

Reasons a colonoscopy is recommended include a positive screening test, rectal bleeding, a persistent change in bowel habit, iron deficiency anaemia, a family history of bowel cancer, surveillance after previous polyps or cancer and assessment or monitoring of inflammatory bowel disease.

Preparing for a colonoscopy

Most people find the preparation the hardest part, and most people also find it is less bad than they expected. It is not painful. It is a day of staying near a bathroom.

Practical questions about referrals, waiting times and what to bring are answered on the patient questions page.

The days before

For several days beforehand, a low-fibre diet: no wholegrains, nuts, seeds, dried fruit or raw fruit and vegetables. Red and purple foods and drinks are avoided because the colouring can be mistaken for blood.

The day before

No solid food. Clear fluids only, which include clear broth, black tea and coffee, clear juice, sports drinks and icy poles. The preparation solution itself is usually taken in two parts, half in the evening before and half around six hours before the procedure. Split dosing like this cleans the bowel better than taking it all at once, which matters, because a poorly prepared bowel can hide the very thing the test is looking for. Several preparations are used in Australia, including Moviprep, Plenvu, Picoprep and the Glycoprep range. You will be told which one to use and exactly when to start.

Medications

Some medicines need to stop before the procedure and some do not. Iron tablets are usually stopped about a week beforehand because they darken the stools, which makes the lining harder to see. Fibre supplements stop a couple of days before. Diabetes medication needs adjusting for a day without food.

Blood thinners and antiplatelet medicines need a plan agreed with the endoscopist before the day, not a general rule, because the right answer depends on which drug it is and why you are taking it. Low-dose aspirin is the one that is usually continued. Never stop a blood thinner on your own.

If you take a medicine whose generic name ends in “flozin”, it stops three days before. Examples in Australia include Forxiga, Jardiance and Steglatro, and the combination tablets Xigduo, Jardiamet, Segluromet, Glyxambi, Qtern and Steglujan. Other brands of the same medicines exist, so check the generic name rather than this list. They are taken for type 2 diabetes, and also for heart failure and kidney disease, so some people take one without thinking of themselves as having diabetes. Combined with the very low carbohydrate intake of a bowel preparation they can cause ketoacidosis, a dangerous build up of acid in the blood, and it can happen while the blood sugar reading still looks normal. The last dose is three days before the procedure, with none on the two days before or on the morning itself.

Anyone taking a diabetes medicine should check their blood sugar through the clear fluid day and keep a clear juice or cordial on hand, one that is not artificially sweetened, in case it drops. Keep to the colours the preparation instructions allow.

Tell the rooms early if you take a GLP-1 medicine, which patients commonly know as Ozempic, Wegovy or Mounjaro. These slow stomach emptying, so food can still be present after the usual fast. The usual instruction is clear fluids only for the 24 hours before the procedure, then nothing by mouth for the last six hours.

On the day

Clear fluids are allowed until two hours before the procedure, then nothing by mouth at all. If you take a GLP-1 medicine, the stricter fasting times above apply instead. You will need someone to take you home, and you cannot drive yourself or travel alone on public transport afterwards.

Sedation is standard in Australia and it is deep sedation rather than a general anaesthetic. Most people are vaguely aware of being in the room and remember very little. The procedure itself usually takes between 20 and 45 minutes. After it you stay in recovery for an hour or two while the sedation wears off.

For 24 hours afterwards, no driving, no operating machinery, no alcohol and no signing legal documents. Most people are back to their usual routine the next day, apart from driving.

You will normally be told what was found before you leave. If biopsies were taken or polyps removed, the pathology takes one to three weeks, and those results are best gone through at a follow-up appointment rather than read cold.

Polyps and what happens when one is found

A polyp is a growth on the bowel lining. Adenomas and sessile serrated lesions are precancerous: left long enough, any of them can turn into cancer, and there is no way to tell which ones will, so they are removed. Small hyperplastic polyps in the rectum and lower colon carry no meaningful cancer risk. Removing the precancerous ones is what makes colonoscopy preventive rather than just diagnostic.

Small polyps are removed as they are found. Larger and flatter ones, the sort that used to mean an operation and part of the bowel being taken out, can often be removed endoscopically instead, by endoscopic mucosal resection (EMR). The best method for a particular polyp is discussed after the colonoscopy, and the removal is arranged as a planned procedure. A/Prof Kariyawasam completed an advanced therapeutic endoscopy fellowship at Concord Hospital and has published on endoscopic resection of large and complex lesions. A small number of polyps are better suited to endoscopic submucosal dissection (ESD), which he does not perform, and those patients are referred to a colleague who does. There is more on the page about polyp removal and EMR.

When the next colonoscopy is due

This depends on what was found, and the intervals come from the national surveillance guidelines rather than from a practice's own preference. As a broad guide:

• One or two small adenomas with no concerning features: five to ten years for most people, or a return to the home screening test after four years
• Three or four small adenomas: five years
• An adenoma 10 mm or larger, adenomas with higher-risk features or five to nine small adenomas: usually three years
• Ten or more adenomas: one year
• A large flat lesion removed in pieces: a check at around six months, or about twelve months if it came out in one piece
• After surgery for bowel cancer: at one year, then at longer intervals

These are guidelines rather than rules, and the interval for any individual takes account of what was found, how well the bowel was prepared, family history and general health. There is a fuller explanation, including the serrated lesion intervals and how Australia compares with the American, European and British guidelines, on the surveillance intervals page.

You should leave with a clear answer about when your next one is due. If you do not have one, ask.

If you are on a surveillance program, a screening kit in between adds nothing. The colonoscopy is already looking for what the kit is looking for.

What are the risks

Colonoscopy is a common procedure in Australia, with around one million performed each year, and serious complications are uncommon. They are not zero, and the honest figures are these.

• A tear in the bowel wall: around one in 1,000 and more likely where a polyp has been removed than where the examination is purely diagnostic.
• Bleeding needing treatment: somewhere between one in 100 and one in 200 after a polyp is removed, and higher where a large polyp has been taken out in pieces.
• Death from a complication: in the order of one in 20,000, concentrated in older patients and those with other serious illness.
• A missed lesion. No colonoscopy finds everything, and how much is missed varies a great deal from one examination to another. Pooled across tandem studies, where people had two examinations in succession, around a quarter of small polyps were missed on the first. What brings that down is well established: thorough bowel preparation, turning the camera back on itself to see behind the folds in the right colon and in the rectum, taking enough time on the way out, and an unhurried examination by an experienced endoscopist.

Set against that, the procedure finds and removes growths that would otherwise have had years to become something worse. For most people being investigated for a symptom or a positive screening test, that balance is not a close call, but it is a conversation worth having rather than a form to sign.

After the procedure, some bloating and wind is normal and settles within hours. Significant abdominal pain, heavy bleeding, fever or vomiting are not normal. If any of those happen, contact the rooms or the hospital where the procedure was done, and if it is severe, go to an emergency department.

How much does a colonoscopy cost in Sydney?

Costs depend on where the procedure is done and on your cover, and anyone quoting a single national figure is guessing. What you are entitled to is a clear answer before you book, not after.

The fees and rebates page sets out how the billing is put together, why a procedure generates several separate accounts and what you are entitled to be told before you agree to anything.

In the public system a colonoscopy is free, and the wait depends on how urgently the referral is categorised. In the private system, Medicare pays a rebate against the relevant item number, private health insurance covers the hospital or day surgery component depending on your policy, and there may be an out-of-pocket amount for the proceduralist and the anaesthetist. Many insured patients pay nothing out of pocket. Some pay a gap.

Before the procedure the rooms will give you the item numbers and a written estimate of any out-of-pocket cost, including the anaesthetist's fee, which is billed separately. Take that to your health fund and ask them to confirm what they will pay. If you do not have cover, ask for the self-funded price in writing. Phone the rooms. Nobody should be finding out what a procedure costs after they have had it.

What makes one colonoscopy better than another

Two colonoscopies are not the same test. How much of the bowel was seen, how clean it was, and how long the examiner spent looking on the way out all change what is found, and all of it is written down. Patients are entitled to ask about any of it.

• Was the whole colon reached? The report should say the caecum or terminal ileum was reached, and there should be a photograph. Accredited practice in Australia is benchmarked at 90 per cent or better.
• How good the preparation was. Most reports give a Boston Bowel Preparation Scale score. Six or more out of nine is adequate. Less than that and the next one should be sooner than the standard interval.
• How long the withdrawal took. Six minutes is the accepted minimum for the inspection on the way out. Longer inspection finds more.
• Detection rates. Endoscopists who hold recertification through the Conjoint Committee are audited on how often they find adenomas and serrated lesions. Any recertified endoscopist has those numbers and can be asked for them.

A/Prof Viraj Kariyawasam is a consultant gastroenterologist and hepatologist with specialist registration in gastroenterology and hepatology. He completed an advanced therapeutic endoscopy fellowship and holds recognition from the Conjoint Committee for the Recognition of Training in Gastrointestinal Endoscopy, the body that certifies endoscopy training in Australia. He is recertified in adult colonoscopy under the Recertification in Colonoscopy Program, which is assessed every three years against audited performance measures, and his recertification runs to 12 May 2029. This can be checked on the GESA register of recertified colonoscopists.

Procedures are performed at Norwest Private Hospital, Macquarie University Hospital, Pennant Hills Day Surgery. Consultations are in Norwest, Rouse Hill, Pennant Hills and Macquarie Park.