Colonoscopy

What is a colonoscopy?

A colonoscopy is where the doctor uses an instrument called a colonoscope to look at the inside of the lining of your large bowel. This is done to see if there are any growths, polyps, cancers, or diseases in your bowel. A colonoscope is a long, thin, flexible tube with a tiny camera and light attached, which allows the doctor to see the pictures of the inside of our bowel on a video screen. The scope bends so that the doctor can move it around the curves of your colon and blows air into your bowel so that the doctor can see better. As a result, you might feel slight pressure, bloating, or cramping after the procedure.

Additionally, this instrument can be used to remove or burn growths, polyps or take biopsies. This procedure starts from your back passage (rectum) and goes to the right side of your bowel (ascending colon). You will lie on your side or back while your doctor slowly passes the colonoscope along your large bowel to look at the bowel lining. The doctor will examine the lining again as the colonoscope is taken out. It may take between 15 — 50 min, and samples of the bowel may need to be removed for pathology tests. The procedure requires sedation by an anesthesiologist.

What are the risks of this procedure?

There are risks and complications with this procedure. They include but are NOT limited to the following:

Common risks and complications include:

  • Mild pain and discomfort in the abdomen for 1 to 5 days after the procedure. This usually settles with walking and moving to get rid of the trapped air.
  • Nausea and vomiting
  • Faintness or dizziness, especially when you start moving around.
  • Headache, pain, redness or bruising at the sedation injection site.
  • Muscle aches and pains.
  • Allergy to medications given at the time of the procedure.

Uncommon risks and complications include:

  • About 1 in every 1000 patients will accidentally get a hole (perforation) to the bowel, causing leakage of bowel contents into the abdomen. Surgery may be needed to repair the hole.
  • About 1 in every 100 patients will experience a significant bleed from the bowel where the polyp was removed. Further endoscopies, a blood transfusion or an operation, may be necessary.
  • Not being able to see the entire bowel. This can happen if your bowel is not completely clean or the colonoscope could not be passed to the end of your large bowel.
  • Missed polyps, growths or bowel disease.
  • Heart and lung problems such as heart attaché or vomit in the lungs causing pneumonia. Emergency treatment may be necessary.
  • Change of anaesthetic from sedation to general anaesthetic.
  • "Dead arm" type feeling in any nerve due to positioning with the procedure — usually temporary.
  • An existing medical condition that you may already have could get worse.

Rare risks and complications include:

  • Bacteraemia (infection of the blood). This will need antibiotics.
  • Stroke resulting in brain damage.
  • Anaphylaxis (severe allergy) to medication given at the time of the procedure.
  • Death as a result of complications to this procedure is very rare.

What are polyps and why are they removed?

Polyps are fleshy growths in the bowel lining, and they can be as small as a tiny dot or up to several centimetres in size. They are not usually cancer but can grow into cancer over time. Taking polyps out is an important way of preventing bowel cancer. The doctor usually removes a polyp during a colonoscopy, using a wire loop to remove the polyp from the bowel wall. An electric current is sometimes also used, and this is not painful.

Will I get the results straight away?

You will need to phone the practice a few days after your procedure and speak to my secretary who will give you the results if they are available. You will also need to book a follow-up appointment for two weeks after your procedure.

What if I don't have the procedure?

Your symptoms may worsen, and the doctor will not be able to diagnose abdominal pain and discomfort.

What are your responsibilities:

You are less at risk of problems if you do the following:

  • Bring all your prescribed drugs, over the counter, herbal remedies and supplements and show your doctor what you are taking. Tell your doctor about any allergies or side effects you may have.
  • Do not drink any alcohol and stop recreational drugs 24 hours before the procedure. If you have a drug habit, please tell the doctor.
  • If you take Warfarin, Persantin, Clopidogrel (Plavix or Iscover), Asasantin or any other drug used to thin your blood, ask your doctor if you should stop taking it before the procedure as it may affect your blood clotting. DO NOT stop taking them without asking your doctor.
  • Tell your doctor if you have:
    • Had heart valve replacement surgery
    • Received previous advice about taking antibiotics before a dental treatment or a surgical procedure.

Preparation for the procedure:

  • Black tarry stools or bleeding from the back passage.
  • A fever
  • Sharp chest or throat pains

Your colon must be completely clean for the procedure to be accurate and complete, so be sure to follow your instructions carefully otherwise, you may need to have the test again. In addition, iron tablets need to be stopped at least one week before your procedure. See this pdf for full instructions.

Are there other tests I can have instead?

There are several tests that can be performed, such as a:

  • Flexible sigmoidoscopy and double-contrast barium enema.

Usually, both would be needed for your doctor to consider that your bowel has been thoroughly investigated.

  • CT Colonoscopy.

A colonoscopy will still be required if some pathology is found.

What can I expect after the colonoscopy?

You will be in the recovery area or ward until your sedation wears off. Your doctor will tell you when to eat and drink after the procedure or ask the nurse. Most times, this is straight after your procedure. You might experience some cramping, pain or bloating due to the air pumped into your bowel during the procedure. This should go away when you pass wind. No driving is allowed 24h after the procedure due to the sedation.

Notify the hospital emergency department straight away if you have:

  • Severe ongoing abdominal pain
  • Have redness, tenderness or swelling for more than 48 h where you had the injection for sedation either in your hand or arm.