Having an endoscopic ultrasound

Endoscopic ultrasound

Preparing for your endoscopic ultrasound

As soon as you receive the date of your procedure:

  • make a note of the date of your appointment
  • arrange for an adult to take you home after your appointment and stay overnight if you plan or have been advised to have sedation

If you do not organise a suitable escort or have not arranged for someone to collect you, we will not be able to give you sedation and your procedure might be cancelled.

Stopping eating and drinking

To make sure the endoscopist has a clear view, your stomach must be completely empty. 

Do not eat anything for 6 hours before your appointment, or drink anything for 4 hours before. You may have small sips of water for up to 2 hours before.

Medicine instructions

We might need to give you special instructions if any of these applies to you. Tell the nursing staff as soon as you receive your appointment date, if you:

  • take medicines to thin your blood or to prevent blood from clotting (anticoagulants or antiplatelets, such as warfarin, rivaroxaban, dabigatran or clopidogrel). You do not need to call if you only take aspirin
  • take sedatives or chronic pain medicines
  • have diabetes and are on insulin
  • have any allergies to any medicines
  • are allergic to latex
  • take any regular medicines including ones you buy from a shop or pharmacy (and any herbal or homeopathic medicines). 

If these instructions are not followed, your procedure will be cancelled and rebooked for another day.

On the day of your procedure

Please be prepared to be with us for the whole morning or afternoon (depending on your appointment time).

Wear loose-fitting clothes on the day of the test. 

Remember, do not eat anything for 6 hours before your appointment, or drink anything for 4 hours before. You may have small sips of water for up to 2 hours before.

Regular medicines can be taken in the morning with a small sip of water. You can take all of your other medicines as normal, unless you have been told otherwise by the doctor or endoscopist.

When you arrive

Once you book in at reception, take a seat in the waiting room. We ask you about your medical history. Please tell us if you have had any reactions or allergies to other examinations in the past.

We also ask you to complete a health questionnaire which will help to speed up your admission or pre-assessment. This can be filled in on the day of your admission in reception.

Your endoscopist (the doctor or nurse doing the procedure) explains more about the procedure and answers any questions.

Once you are ready we take you to a waiting area.

You might be asked to remove your shoes, loosen any tight clothing and remove any false teeth or glasses. You can change into a gown is you wish. You might want to bring your dressing gown and slippers with you (we do supply non slip socks). 

You will need to take off all your jewellery, so it’s best if you leave any valuables at home as we cannot be responsible for any valuables in the unit. You will need to keep your belongings with you at all times.

All metal needs to be removed as we use an instrument that uses an electrical current to stop any bleeding.

Please be prepared to be with us for the whole morning or afternoon (depending on your appointment time).

Our endoscopists are usually running up to 5 procedure rooms at the same time, so sometimes another patient who arrived after you may be called in before you are. This does not mean you have been forgotten, but that the other person is on a different list to you. We do everything we can to avoid keeping you waiting and will keep you updated, but because every procedure takes a different time to complete, it’s hard to give exact timings.

We also deal with emergencies in the department. This means we might have to ask you to wait. We are sorry if this happens, but please be patient and check at the reception desk if you are concerned.

Having sedation

If you are having sedation, we insert a small needle into your arm or hand and give an injection through this in the procedure room. You can also have an injection of painkillers.

Sedation is medicine that makes you feel relaxed and sleepy but does not put you to sleep. You will be able to respond to the doctor or nurse. You might not remember the procedure afterwards. 

During the procedure

We give you a local anaesthetic spray to numb the back of your throat. You might have the sensation of gagging and retching as this is a natural reflex of the endoscope touching the back of the throat.

You will be placed on your left side on a trolley. To keep your mouth slightly open, a mouthpiece will be placed between your teeth which might be held in place by nurse. The ultrasound scope will be gently inserted into your mouth and passed down into your stomach. If you have too much saliva in your mouth, the nurse will clear this using a sucker (like at the dentist).

Sometimes a tissue sample (biopsy) will be taken for analysis. The tissue is taken through the endoscope using tiny forceps or a fine needle. 

The test usually takes 15 to 30 minutes. When the examination is finished, the endoscope will be removed quickly and painlessly.

After your procedure

You will be taken to the recovery area. If you have had sedation, you will need to rest quietly until your observations (heart rate, blood pressure, pulse) are stable, which is usually 1 to 3 hours.

When you are stable we will take you to the discharge waiting area. Your cannula will be removed.

You will not be able to eat or drink anything until your swallow reflex returns which usually takes about 45 minutes. After this, you can eat and drink as normal, unless the doctor or nurse tells you otherwise.

You will probably have a sore throat for the rest of the day and this is normal.

We will discuss your procedure, outcome and next steps with you before your discharge and give you a copy of your report.  

You will be able to leave hospital after you are stable (at least 1 to 3 hours after your procedure). A doctor will check you to make sure you are fit to leave.

If you had sedation, you must have someone to escort you home and stay with you overnight. They should come with you for the appointment or be contactable by phone when you are ready to leave.

If you cannot arrange for someone to collect you and stay with you overnight, please contact us to discuss alternative arrangements.

Resource number: 0451/VER8
Last reviewed: February 2023
Next review: May 2024

Contact us

If you need to change or cancel your appointment, please call 020 7188 8887.

Contact the endoscopy unit for advice from Monday to Friday, 9am to 5pm.

Nurse in charge: 020 7188 7188 ext 54059

St Thomas' reception desk: 020 7188 7188 ext: 54046

In an emergency, out of hours (6pm until 8am the next day and on Saturday or Sunday). Phone 020 7188 7188 and ask to be put through to the on-call gastroenterology registrar.

Do you have any comments or concerns about your care?

Contact our Patient Advice and Liaison Service (PALS)

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