Sigmoidoscopy

What is a Sigmoidoscopy?

Sigmoidoscopy is a minimally invasive diagnostic procedure that allows our specialist gastroenterologists to examine the rectum and the lower portion of your large bowel (sigmoid colon) using a thin, flexible endoscope. While a full colonoscopy examines the entire colon, sigmoidoscopy focuses only on the lower 40-60cm of the bowel, where many common conditions develop.

Sigmoidoscopy can detect certain conditions at an early stage and radically improve the outcome of treatment. An Imperial College study discovered that screening of this kind led to 56% fewer cancers in the lower bowel, and the risk of dying from these cancers dropped by two-thirds (66%) in those being screened. (https://news.cancerresearchuk.org/2017/02/22/a-one-off-bowel-scope-helps-prevent-bowel-cancer-but-its-taking-time-to-reach-everyone-eligible/)

This targeted examination is particularly valuable for investigating symptoms affecting the lower digestive system and can often provide definitive answers in a shorter, more comfortable procedure than a full colonoscopy. At LivingCare, we perform sigmoidoscopy at both our Leeds and Sheffield locations, ensuring convenient access to expert care across Yorkshire. 

Our consultants typically recommend sigmoidoscopy when you experience:

• Bleeding (bright red or dark blood in stool) or unexplained iron deficiency
• Changes to your bowel habits over more than two weeks
• Unexplained diarrhoea or constipation, or unusual discharge
• Persistent lower abdominal cramping or feeling of incomplete emptying
• Unintentional weight loss

You are recommended for a sigmoidoscopy if you have specific medical concerns. If your family has a history of colorectal cancer or inflammatory bowel disease, you may want the peace of mind that screening can offer. You can also use a sigmoidoscopy to monitor conditions like ulcerative colitis or to track your recovery from colon cancer treatment. Additionally, a sigmoidoscopy is a helpful tool to investigate unexplained rectal symptoms or test results from a stool test.

Studies show that flexible sigmoidoscopy can detect up to 75% of colorectal abnormalities in the examined area, making it a highly effective diagnostic tool for lower bowel conditions. With LivingCare, you’ll typically discuss your results immediately and receive any biopsy results in 7-10 days.

How a Sigmoidoscopy Works 

Our specialists use state-of-the-art, flexible endoscopes with high-definition cameras and LED lighting. They are skinny: around 12mm wide and 60cm long. Despite their size, these advanced instruments deliver exceptional image quality while remaining comfortable for patients. 

Step-by-step procedure:

1. You'll be positioned comfortably on your left side with your knees drawn up
2. The endoscope is gently inserted through the rectum using careful, controlled movements
3. The flexible tube is slowly guided around the natural curves of your sigmoid colon
4. Visualisation: A small amount of air is introduced to gently open the bowel walls for clear viewing
5. Your consultant methodically examines the bowel lining, looking for any abnormalities. Any findings are documented with high-resolution images for your records
6. The endoscope is carefully withdrawn while conducting a final examination

Additional procedures may be necessary, such as biopsy collection, where small tissue samples are taken painlessly for laboratory analysis. A sigmoidoscopy can also be used to remove small polyps using specialised instruments, treat bleeding areas, or remove small lesions.

What to Expect When Receiving a Sigmoidoscopy

Before Your Appointment

What to eat

Starting 48 hours before your appointment, you must avoid high-fibre foods, including whole grains, nuts, seeds, and raw vegetables, and foods with skins – like tomatoes, grapes and peas. 

You should choose low-fibre alternatives, like white bread instead of wholemeal, and white rice instead of brown rice. You should also choose white meat, fish and eggs instead of red meat. 

Managing your medications

Stop taking iron supplements 5 days before the sigmoidoscopy. You can continue taking other essential medications unless your doctor advises you not to. If you take blood thinners, you may need to adjust them. LivingCare will discuss this with you and discuss any diabetes medications or insulin requirements. 

Preparing for the procedure 

We'll provide specific instructions for bowel preparation, typically involving drinking clear liquids only for 12-24 hours before the procedure, and taking prescribed solutions to help clear the lower bowel. We’ll give you a detailed timeline for all these steps. 

During Your Appointment

Comfort Options:

• No sedation: Most patients (approximately 80%) find the procedure comfortable without sedation
• Mild sedation: Available if you prefer to be more relaxed during the procedure
• Local anaesthetic gel: Used to make insertion more comfortable

Procedure Timeline:

• Check-in and preparation: 15-20 minutes
• Actual procedure: 5-20 minutes (average 10 minutes)
• Recovery (if sedated): 30-60 minutes
• Total visit time: 1-2 hours

After Your Appointment 

If you underwent the procedure without sedation, you can resume normal activities immediately. If you took sedation, you’ll need to stay in the recovery area for monitoring for 30-60 minutes, and have someone to drive you home. You should rest for the remainder of the day and avoid alcohol for 24 hours.

Risks and Complications of a Sigmoidoscopy

A Sigmoidoscopy is considered a safe test. However, being aware of the risks and side effects is important.

Common, Minor Effects (experienced by some patients):

• Mild cramping during air insertion (temporary)
• Slight bloating for a few hours
• Minimal spotting if biopsies are taken

Serious Complications (less than 1 in 5,000 procedures):

• Bowel perforation (tear in the bowel wall)
• Significant bleeding requiring intervention
• Reaction to sedation (if used)

How to Recover Following a Sigmoidoscopy

Resume normal eating immediately unless advised otherwise. You may return to work the same day if you did not have sedation. However, if you had sedation, you should wait until the next day before you return to work. You can go back to normal activities and exercise after 24 hours. 

References

1. British Society of Gastroenterology. (2024). Sigmoidoscopy Guidelines and Patient Information.
2. NHS (2024). Sigmoidoscopy
3. Royal College of Surgeons. (2024). Lower GI Endoscopy Guidelines.
4. European Society of Gastrointestinal Endoscopy. (2024). Quality Standards for Sigmoidoscopy.