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Flexible Sigmoidoscopy

What is a Flexible Sigmoidoscopy?

A Flexible Sigmoidoscopy is a procedure that allows us to examine the lining of the lower part of the colon (large bowel). It is useful in diagnosing a range of symptoms and for monitoring pre-existing conditions.

A flexible tube called a colonoscope which is about the size of your index finger, is passed through your back passage and manoeuvred around the colon by a specially trained doctor or nurse, called an endoscopist. The lining of the bowel is examined thoroughly by the endoscopist throughout the procedure to help determine a cause for your symptoms.

Preparing for your procedure

In order to perform the examination accurately, your rectum and lower bowel must be empty. Your bowel preparation will be sent to you separately from this information pack. Along with the preparation will be instructions on how to prepare for this test. It is crucial that you follow the instructions on diet, fasting and how to take the bowel preparation. This will ensure the preparation works well, we get the best possible views of the colon and we do not have to rebook the procedure.

You will receive a consent form, a health questionnaire and additional documentation in the post. These can also be downloaded below. Please follow the Low Residue Diet Sheet, which we recommend starting 3 days before the procedure (Note: This may be different to the guidance in the bowel preparation instructions). Please inform us if you are unable to take all of the bowel preparation or if you are sick whilst taking the preparation.

Please make yourself familiar with the consent form and make sure you have this with you to complete with the nurse before your procedure. Please also complete the health questionnaire prior to arriving for your procedure.

Any regular medication may be taken on the morning of the procedure, with a very small amount of water. If you are on anticoagulant or antiplatelet medication, please read our leaflet, Anticoagulant & Antiplatelet Advice, available below. If you are on iron tablets, please stop taking them 7 days before the test. If you are taking the oral contraceptive pill, additional precautions should be taken for 7 days following taking the bowel preparation.If you have been prescribed antibiotics for diverticulitis SINCE your GP or doctor referred you for this procedure, please call the bookings team on 0333 202 3187 for advice. Please bring with you a list of all current medications.

Please drink plenty of additional water on the lead up to the test, this will improve the effectiveness of the preparation and keep you hydrated. You can keep having sips of water up until 2 hours before your procedure.

What to expect on the day

What happens before your procedure?

When you arrive at the unit, please report to reception. You will be asked to take a seat in the waiting area until the admissions nurse is ready to see you. Although we endeavor to see you at your allotted appointment time, we do sometimes experience delays in our list. Thank you for being patient, the reception staff and admissions nurse will be able to keep you updated on any delays.

In the admissions room, the nurse will take some information from you relating to your procedure and talk you through what to expect during your appointment. The procedure will be explained to you, along with the risks, benefits and alternatives of the procedure. Once they are satisfied you understand what is going to happen, they will sign your consent form with you. This is a good opportunity to ask any questions you may have regarding the examination.

Most people decide they do not need sedation or choose Entonox (Gas & Air) for the procedure. If you feel there is a need, there is an option of a sedative injection as well. You will be given a pair of shorts to put on (you will keep your top on) and a basket to put your belongings in. If you decide to have a sedative injection, a cannula will be inserted into your arm or your hand. You will remain here until the procedure room is ready for you. All of your belongings will either stay with you or remain in your pod area.

Please Note: Although the examination takes 20-30 minutes, please expect to be at the clinic for about 1 – 2 hours, due to the time it takes to get you admitted and then discharged after your examination. This does vary from clinic to clinic, but the admitting nurse will be able to give you a better idea on the day. Please bear this in mind when organising people to collect you. 

What happens during your procedure?

You will be taken to the procedure room where the nursing staff will introduce themselves, along with the Endoscopist if you have not met them previously.

The endoscopist will talk to you about your reasons for having the procedure. You may want to tell them about any symptoms you have been having and how long they have been occurring.

The nurse will put a monitor on your finger and a blood pressure cuff on your arm, this is so that we can monitor your observations throughout the procedure. You will then position yourself on the trolley (lying down on your left-hand side initially). If you are having sedation, it will be given at this point.

It takes approximately 2 minutes for the sedation to take effect. If you have not opted for sedation, you will be shown how to use Entonox, gas & air, as an alternative pain relief.

The endoscopist will apply some lubricating gel to your back passage and perform an examination with his/her finger first. The colonoscope, which has a camera and a light at the end of it, is then passed through your back passage. Slowly, air or carbon dioxide will be passed through the tube into your large bowel to open it up to ensure the endoscopist has clear views of your bowel lining. This may give you a ‘wind like’ pain but this does not usually last long. You may get the sensation of wanting to go to the toilet, but as your bowel is empty, this is unlikely to happen. Please do not feel embarrassed if you must pass wind, this is entirely normal.

The endoscopist may want to give you an intravenous bowel relaxant, called Buscopan, during the procedure. You will be asked to change position at times, this helps to move the scope around the bowel and makes the procedure more comfortable. Sometimes, the endoscopist will need to take biopsies. These are small samples of tissue that are removed painlessly, using small forceps that are passed through the colonoscope. One of the aims of a flexible sigmoidoscopy is to detect polyps, which are growths that can occur on the bowel wall. Some are perfectly innocent, but others can slowly develop into bowel cancer if they are not removed. Removing polyps is a simple and painless procedure, this is termed a polypectomy. If the polyp is large you may have to come back for another procedure with an endoscopist who specialises in the removal of large polyps.

What happens after your procedure?

Once the procedure is completed, you will be taken through into the recovery area, (on the trolley, if you’ve had sedation) and you will be made comfortable.

You may feel a little bloated with wind pains, however, these usually settle quickly once you have passed the wind. If the endoscopist has used a lot of water to flush through the scope into your bowel, you may notice some leakage afterwards. Please do not worry, this is completely normal.

Once the nurse in the recovery area is satisfied you have recovered, you will be offered refreshments. The cannula will be removed after you have had a drink.

Before leaving the endoscopy unit, the results of your procedure will be discussed with you. This is a good opportunity to ask any questions you may have about your results.

The nurse will discuss your aftercare information, including what to expect in the hours and days following your procedure. Once the nurse is happy that you are feeling well and your observations are satisfactory, you will be allowed to get up and go home. You may experience some mild discomfort and bloating following your procedure. You can eat and drink normally immediately after your test. Any biopsies or polyps that have been removed are sent to a laboratory with results taking up to 4 weeks.

If you have had NO sedation or Entonox you may drive after 30 minutes after your procedure and resume normal activities. 

If you have had Entonox ONLY there are no known side effect so you may resume your normal daily activities.

If you have sedation, the effects of the sedation can last for up to 24 hours. Although you may feel recovered, your judgement and reactions may be impaired during this time. It is essential you have someone to take you home and stay with you for the remainder of the day and overnight. It is recommended that you rest quietly for the remainder of the day.

Frequently asked questions

Is there an alternative procedure I could have?

For some conditions it may be possible to perform a CT examination to look at your large bowel. The disadvantage of this procedure is that a biopsy cannot be taken, or a polyp cannot be removed.

Can I have sedation and pain relief?

Intravenous sedation and pain relief are available for patients having this test, should you choose to have it. You can discuss this with the admitting nurse, or you can call us for more information before your procedure.

Please Note the sedation we offer is not a general anaesthetic but is a ‘conscious sedation’ used to relax you. You will not be fully asleep and will still be aware of your surroundings.

Can there be complications or risks?

As with most medical procedures, there are some risks involved. The admissions nurse and the endoscopist will explain this to you. Having a flexible sigmoidoscopy procedure is low risk and complications are uncommon, however, you need to be aware they can happen.

What if my bowel preparation hasn’t worked?

Please be patient. The laxative usually works within a few hours, but this can sometimes take a little longer depending on your age. Once it does start working, please stay close to a toilet as sometimes not warning may be given.

What do I do if I am sick with the preparation?

Please telephone the department if this happens so we can provide further advice.

Will I get my results on the day?

Upon completion of your procedure and once you have recovered, the findings will be discussed with you. If you have had any biopsies taken or polyps removed these will be sent away for testing. You will be given a copy of the procedure report and a copy will also be sent to your GP and your referring doctor.

Patient Information Leaflets

Whilst you will receive paper copies of our patient information leaflets in the post, you can also read them here and/or download them to your device if you wish.