Advice after your nerve block for surgery
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Introduction
We have given you this factsheet because you have an appointment for a CT enterography scan. Please make sure you read this information and follow the instructions carefully before your procedure. If you have any further questions, please speak to a member of your healthcare team who will be pleased to advise you.
The procedure involves a computerised tomography (CT) scanner taking images of your abdomen and pelvis. These images are cross-sectional (like slices) and are used to produce 2D and 3D images of the small bowel. The small bowel is normally collapsed and as such difficult to assess on CT. For us to be able to distend and therefore visualise the lumen of the bowel adequately we will ask you to drink a liquid solution containing Mannitol as part of the examination. Mannitol as well as retaining fluid within the small bowel also has certain imaging characteristics which allow for easy visualisation of any small bowel abnormalities.
Before your appointment
Please let us know if:
- you normally require the Vascular Access Team for injections
- you have limited mobility and will require assistance to get on and off the scanner.
- you will need an interpreter. We are not able to use family members or friends to interpret.
- there is any possibility that you may be pregnant.
- If you suffer from diabetes, bring any medication you take and something to eat with you for after the scan. Please also notify the department so an early appointment can be made for you.
In order to make your appointment run more smoothly, please let us know if any of these apply, in advance, by calling our bookings team (contact details are displayed on the main Radiology page).
Food and Drink
To prepare your small bowel for the study, you must not eat anything for at least 6 hours prior to your scan, and may only drink clear fluids (eg squash or black tea/coffee).
On Arrival
Please arrive 60 minutes before your scan time.
On arrival in the department you should check in at the reception desk. Bring this letter with you and be prepared to confirm your details with the receptionist. All patients from 12-55 years of age (regardless of gender) who will undergo a Radiology procedure will be asked about the possibility of them being pregnant.
You will be asked to drink (750ml) of Mannitol solution (this is a water based solution which can be flavoured with either orange, lemon or blackcurrant squash if you prefer). This must be consumed over a period of 45 minutes. It is important that the entire small bowel is adequately distended and therefore ask you to drink the liquid at a steady rate over this time period. This helps enlarge the small bowel and provide better pictures. However, this can cause symptoms of nausea, bloating and diarrhoea which may last for up to 24 hours. You may wish to take this into account when planning what to do in the couple of hours immediately after your scan. It is also important to drink plenty of water following your scan.
If you have difficulty drinking the fluid or feel nauseous please contact a member of staff.
The procedure
- A Radiographer or Health Care Professional will call you from the waiting room for your CT scan.
- We will ask you a series of questions to make sure the scan is safe and can then go ahead.
- A small needle (cannula) will be placed into your arm, in preparation for your scan.
- There may be breathing instructions for you to follow; these may require you to hold your breath for up to 10 seconds. If you struggle to hold your breath for this long or find it difficult lying flat on your back, then let the Radiographers know when you arrive.
- You will also be given a bowel-relaxing injection (Buscopan) via this needle; this helps to reduce the movement of your bowel during the scan, making the images clearer to aid diagnosis. As a result of this muscle relaxant, you may experience some blurring of vision but the effects of Buscopan are short lived. You are advised not to drive until any effects have worn off. In the very unlikely event that you develop painful, blurred vision in one or both eyes following the examination, you must attend the emergency department.
- The radiographers will be in the CT control room but you will be able to talk to them via an intercom, and they will be watching you all the time.
- During the scan the contrast dye will be injected via the cannula in the arm. Some patients may experience a general sensation of warmth or a metallic taste in your mouth. These sensations are normal and pass within minutes.
- Following the scan you will be asked to remain in the department for 10-15 minutes. After this time we will remove the cannula and you can leave the department.
After the Examination
You will be free to resume your normal daily activities
The Results
The results of your scan will not be given to you immediately after the scan. The images are interpreted by a Radiologist (doctor specializing in medical imaging) and sent back to your Consultant or GP who referred you for the scan. The result will be sent to your referring Doctor. This can take up to 4 weeks
Are there any risks?
- There is exposure to X-ray radiation during the procedure. However, the amount of radiation you will receive is kept to as low as reasonably possible.
- Some people may have a rare allergic reaction to the x-ray contrast. We will go through a safety checklist before the procedure to identify if you are at increased risk. A hot flush, feeling of passing urine and metallic taste are common side effects of the x-ray contrast.
- No test is always 100% accurate and both CT enterography can miss small bowel abnormalities
Other side effects that may occur include:
- Painful, blurred vision of one or both of your eyes. This is a rare side effect from the muscle relaxant (Buscopan). If you experience this, you must attend hospital immediately.
- Abdominal discomfort. This should get better as you move around and start to eat.
Contact us
If you have any queries relating to this information, please contact the Radiology service.
About this information
Service:
Radiology
Reference:
PILS-CT.5
Approval date:
2 October 2024
Review date:
2 October 2027
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Important note
This page provides general information only. It is developed by clinical staff and is reviewed regularly every 3 years for accuracy. For personal advice about your health, or if you have any concerns, please speak to your doctor.