A consultation with a stethoscope on top of it Endoscopy
Flexible Sigmoidoscopy
Why is a flexible sigmoidoscopy performed?

Your doctor may recommend you have a flexible sigmoidoscopy if you have any of the following problems:

  • Bleeding from the bowel
  • A change in bowel habit
  • Diarrhoea or constipation
  • Rectal or anal pain
  • Inflammatory bowel disease (ulcerative colitis
    or Crohn’s disease)
  • Previous polyps or bowel cancer
  • Haemorrhoids
A flexible sigmoidoscopy is a procedure which allows your specialist to see inside the rectum and lower part of your large bowel (sigmoid colon) and examine the lining of the bowel directly. This is performed using a narrow flexible tube called a colonoscope which has a light source and camera in the tip that captures images of the inner lining of your bowel. The colonoscope is placed into your anus (bottom) and the doctor slowly advances into the rectum and lower colon while viewing the images on a video screen.
What is the preparation for a flexible sigmoidoscopy?

It is important that the bowel is completely empty for the procedure to be accurate, thorough and safe . Preparation for sigmoidoscopy usually requires the use of one or two enemas administered by a nurse at the clinic just prior to your procedure. This will allow you to empty all faecal material from your lower bowel and enable the doctor to get good views of the lining of your bowel. Sometimes dietary modifications and laxatives are also required. Specific written instructions will be given to you by the Cambridge Specialist Centre.

Inform your specialist prior to the Flexible Sigmoidoscopy if you have any of the following:

  • Allergy to any medication or anaesthetic
  • Diabetes
  • Heart or lung problems including pacemakers and artificial heart valves
  • Artificial joint replacements
  • Are pregnant or breast-feeding
  • Take blood-thinning medications (these may need to be stopped prior to the procedure)
  • Take iron supplements (these need to stop one week before the colonoscopy). Iron can produce black stool which can coat the lining of the bowel, reducing visibility.
  • Unless otherwise instructed, continue taking any regularly prescribed medication.

What happens on the day of your flexible sigmoidoscopy?

After arrival to the Cambridge Specialist Centre you will be admitted by a nurse and you will see the specialist performing the procedure to discuss and sign a consent form. You will then be asked to change into a hospital gown. An enema will be administered by a nurse which should make you need to pass a bowel motion. The nurse will assess whether a second enema is needed to ensure the lower bowel is clear of faecal residue.

The flexible sigmoidoscopy will be performed in a fully equipped examination room in our endoscopy suite. Intravenous medication to make you sleepy can be used for the procedure but it is not usually required. You will be assisted and observed by two endoscopy nurses throughout the procedure and your heart rate and oxygen levels will be monitored. In most instances you will be lying on your left side with your knees drawn up toward the chest. Your specialist will insert the colonoscope through the anus and gently advance through the lower part of your bowel. Carbon dioxide is used to inflate the bowel to provide better views. You may experience a sensation of fullness, bloating, pressure or cramping as the scope moves inside.

As the instrument is withdrawn, a careful examination is made of the lining of the colon. Tissue samples may be taken with tiny biopsy forceps inserted through the scope. Polyps may be removed with snares, and photographs may be taken. The procedure generally takes about 10-15 minutes but could be longer particularly if you require any endoscopic treatment during the test.

What happens after a flexible sigmoidoscopy?

After your flexible sigmoidoscopy you will be wheeled into the recovery room where you will rest. If you have received intravenous sedation you will be required to be in the recovery room for at least one hour after the procedure. When you wake up your specialist will discuss your examination results with you and a written summary will be given to you for your reference.

A light snack will be served before you leave the Cambridge Specialist Centre. You are able to return to your normal diet following discharge.

If you have received sedation you must have someone to take you home after the test and stay with you, as you will be drowsy. This generally wears off after a few hours. You will not be allowed to drive a car, operate machinery or make any important decisions for 24 hours as your judgement and reflexes may be impaired.

The sedation may also affect your ability to recollect details of the colonoscopy. You should stay off work the day of your procedure but can resume normal activities the following day.

Results

Flexible sigmoidoscopy findings may include the following

  • Inflammation and ulceration
  • Polyps. These are small growths on the inner lining of the bowel. Most polyps are benign (not cancerous), but some polyps are precancerous.
  • Diverticulosis (abnormal ‘pouches’ in the lining of the intestine)
  • Lower gastrointestinal bleeding
  • Cancer / tumour

Any tissue samples are sent to the pathology department for examination under a microscope. These results will be sent to your specialist and GP within 5-7 days. A typed report of your procedure will also be sent to your GP. You may be asked to make a follow-up appointment with your specialist to discuss your results.

Patients who have polyps removed which are precancerous are usually asked to return for a colonoscopy so that the entire bowel can be visualised. More vigorous colon cleansing is required for colonoscopy. Removal of all precancerous polyps during colonoscopy has been shown to reduce the risk of colon cancer.

Safety and Risks

A flexible sigmoidoscopy is generally a very safe and simple test. Complications are rare but may include:

  • Perforation (tearing) of the bowel wall, which may require a repair
    operation (fewer than 1 out of 1,000 tests).
  • Heavy or persistent bleeding from biopsy or polyp-removal sites (1 out of 1,000 tests).
  • Adverse reaction to sedative medication, causing breathing problems or low blood pressure (4 out of 10,000 tests).
  • Missed polyps or lesions in the bowel.
  • Nausea, vomiting, bloating or anal irritation.

Contact Us

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