Please read this information carefully before coming in for your Natural Sleep Electroencephalography (nsEEG)
What is a natural sleep EEG?
A nsEEG involves recording the electrical signals from the brain, whilst you are awake and asleep. An EEG looks at how the brain is functioning rather than taking images as you would see in a scan. It is a non-invasive, painless procedure and you won’t need to shave or cut your hair.
Why do a nsEEG?
If you have been experiencing possible fits, seizures, faints, or “funny turns” you may be referred for a nsEEG. The nsEEG will assess your ongoing brain activity whilst awake and during sleep.
What happens during a nsEEG?
A nsEEG will take approximately around 90 minutes in total. Your head will be measured, then rubbed gently before 28 small metal electrodes attached to wires are applied using a soluble sticky paste. 2 electrodes will also be applied to your arms or shoulders to measure your heart rate during the EEG. You will be asked to relax on a bed with your eyes closed, the lights will be turned off and you will be allowed to drift off to sleep.
Natural sleep EEG
For this test you do not need to sleep deprive yourself, but we ask you not to nap or have any caffeinated drinks before your visit. Once the recording has finished all electrodes will be removed and your head wiped with warm water. You may still need to wash your hair when you get home.
Preparing for the test
- You must arrive with clean, dry hair free from grease, gel, wax or other hair products. You may wish to bring a comb or brush to tidy your hair after the test.
- You should avoid coffee or other caffeinated drinks before the test as this can affect your ability to fall asleep.
- We advise you have something to eat before coming for the test, preferably within 1.5 hours as you are more likely to sleep if you are full.
- Continue taking all regular medication as normal before the test.
- You will be asked if you understand this information and whether you consent to the test before we start. At your appointment, you are welcome to ask the neurophysiologist doing the test to give you further information or to explain more about the procedure.
When will I get my results?
You will not get your results straight after the test or see a doctor on the day as the nsEEG needs to be fully analysed. A full report will be sent to the GP or consultant who referred you within 2 weeks, they will then contact you to discuss the results. Please note, results are not sent directly to you.
Contact details
This information is intended as a guideline only. If you have any further questions about your test (excluding about results) please contact the department on the numbers below and a member of staff will be happy to help.
Your responsibility as a patient
Outpatient services at North Bristol NHS Trust are in great demand. Even so, every week an average of 600 patients fail to attend, which wastes appointments. Please tell us with as much notice as possible if you no longer need your appointment and we can allocate this to another patient.
What if I am unwell or need to change my appointment?
If you have an infectious condition, such as COVID-19, measles, mumps, chickenpox, flu, stomach upset, have head lice, or are unable to attend your appointment for any other reason, please let us know with as much notice as possible so that your appointment can be rescheduled and offered to someone else.
If you want to change the appointment for a second time, we cannot offer you another date unless there are exceptional circumstances.
What if I don’t attend?
We will assume that you no longer require your appointment, and we will not offer you another one. We will write to the consultant/doctor who referred you and inform them that you did not attend.
© North Bristol NHS Trust. This edition published December 2024. Review due December 2027. NBT003742
