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Chart & Stethoscope


What is a flexible sigmoidoscopy?

Flexible sigmoidoscopy allows inspection of the lining of the anus, rectum and lower part of the colon. It uses a flexible tube with a ‘video camera’ at the tip. The instrument is about 1cm in diameter. The colon (large intestine) is approximately 1.5 to 1.8 metres in length; a flexible sigmoidoscopy examines only the last 30 to 60 cm.  This last part of the colon, just above the rectum is called the sigmoid colon.

Why have a flexible sigmoidoscopy?

A flexible sigmoidoscopy exam can help your doctor explore possible causes of abdominal pain, rectal bleeding, changes in bowel habits, chronic diarrhea, and other intestinal problems. The procedure is used to look for early signs of colorectal cancer.  In some individuals with a family history, this may also be an appropriate test to check for bowel cancer.

As cancer of the bowel can arise from pre-existing polyps it is recommended that all polyps found at the time of a sigmoidoscopy be removed. Most polyps can be removed (i.e. Polypectomy) during a sigmoidoscopy. If you have any queries or reservations about this, please discuss this with your doctor prior to being sedated.

How is flexible sigmoidoscopy performed?

A sigmoidoscopy is performed under sedation, as a day only procedure. Once anaesthetic sedation is given, the doctor inserts the flexible colonoscope (‘scope’) through the anus and slowly guides it into the colon whilst air is inflated into the bowel to expand it and allow for careful examination. A small camera in the end of the scope transmits a video image to a monitor, allowing the doctor to carefully examine the intestinal lining.

Depending on the findings, biopsies may be taken and sent to pathology. The doctor and medical staff monitor your vital signs during the procedure. The procedure itself takes about 10 to 20 minutes.

How do I prepare for a flexible sigmoidoscopy?

Your doctor will tell you what preparation is required, however as the procedure is performed under sedation, you will need to fast and refrain from drinking for a period of 8 hours prior to the procedure. Usually, an enema (a solution that is inserted into the rectum to clean the lower bowel) is the only preparation required.

What do I do prior to the procedure?

  • Complete and return all pre-admission paperwork well prior to your scheduled appointment; this includes informing the hospital of all medical conditions and any medications or supplements taken regularly;

  • Familiarise yourself with the patient information brochure provided to you prior to your procedure.This provides all the necessary details regarding the hospital facility and what to bring on the day;

  • You will need to fast and refrain from drinking. Have no food or drink for 8 hours prior to your appointment time;

  • Prescribed medications should be taken as per normal with a small sip of water up to 2 hours prior to your procedure. Do not take any medication within 2 hours of arriving for your procedure.

What are the possible complications and associated risks?

Although complications can occur, complications arising from a flexible sigmoidoscopy are very uncommon. The chance of complications depends on the exact type of procedure that is being performed and other factors including your general health. Most surveys report complications of 1 in 1,000 examinations or less.

Perforation (making a hole in the bowel) or major bleeding from the bowel is rare, but if it occurs, you may require surgery. When operations such as removal of polyps are carried out at the time of the examination, there is a slightly higher risk of perforation or bleeding from the removed site. If there is a suspicion of a perforation after your procedure the doctor may decide to transfer you to hospital for further care. If an ambulance is required the associated fees will be payable by you or your health fund.

Extremely rarely, individual patients may also inhale some fluid that may still be present in the stomach (resulting in pneumonia).

Complications that can also occur from a reaction to sedatives used, although they are uncommon. If you wish to have full details of rare complications explained to you in more detail please speak to your doctor prior to the procedure.

What happens after the flexible sigmoidoscopy?

Following the procedure, you will remain in recovery for at least an hour. You will usually be given something light to eat and drink once you are awake. The doctor will then provide you with a brief overview of your results and let you know if you require any follow up appointment at our hospital or with your local GP.

It is very important that you do not try and get out of bed until instructed to do so by nursing staff. You will still be affected by the sedation even after you think it has worn off.  Very rarely you may pass a small amount of blood following the procedure.

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