Sleep EEG for Children

18th, Aug 2014

Dr Deirdre Peake - Consultant Paediatric Neurologist talks to us about EEG tests. EEG helps determine if your childs level of alertness or consciousness is normal, if abnormalities exist, if a patient has a tendency to have seizures or convulsions, and if a patient is likely to have a particular kind of epilepsy.

An EEG determines if the patient’s level of alertness or consciousness is normal, if abnormalities exist in one specific part of the brain, if a patient has a tendency to have seizures or convulsions, and if a patient is likely to have a particular kind of epilepsy.

This blog aims to provide information for parents or carers who are asked to bring a child for a sleep EEG test. It describes what happens before, during and after the test, together with an explanation of any risks. You may wish to discuss the details with your child or let them read the information themselves, as appropriate.

What is an EEG?

An EEG (Electroencephalogram) is a test that measures the electrical activity in the brain, called brain waves. An EEG measures brain waves through small button electrodes that are placed on your child’s scalp.

What is a Sleep Deprived EEG?

If you receive an appointment for your child to have a sleep EEG he/she will be asked to sleep deprive your child and / or will be prescribed melatonin . Useful information can show up during drowsiness or if your child falls asleep during the recording. A video recording will be taken at the same time as the EEG. This is done so that any movements and/or behaviour noted during the recording can be linked to the brain activity seen on the computer.

What should I do before the tests?

For a sleep recording you will be asked to deprive your child of sleep prior to the EEG test. This means that your child will be tired and will hopefully fall asleep during the recording. The amount of sleep deprivation tolerated will vary from child to child. As a guide we suggest:-

Children aged 12 years and over	A full night without sleep is preferable.
Children aged between 6-12 years	Should have at least 6 hours less sleep than usual and should be woken very early on the morning of the appointment.
Children aged between 4-6 years	Should be kept up for 1-2 hours past bedtime and woken 1-2 hours earlier than usual, with a busy morning and lunch as usual.
Babies and children under 4 years	It may be enough to cut out their daytime nap if they have one

We will usually speak to you to discuss your child’s usual sleeping patterns and requirements for sleep deprivation when arranging the timing of the appointment.

In addition please note the following:-

Please ensure that your child’s hair is clean and free from gel/lacquer.
If your child has head lice, please complete treatment before the test.
Your child should take any medication as normal unless otherwise directed by your doctor. It would be helpful if you could bring a list of any medication your child is taking.
Your child should eat as normal.

If you feel your child is likely to fall asleep in the car on the way to hospital it can be helpful to have another adult to travel next to them and keep them alert. Alternatively you could come to the hospital earlier in the day and bring toys/food to keep them busy.

What does the test involve?

As with the routine EEG, the test will be carried out by a Clinical Physiologist who will explain the procedure and take some details of your child’s medical history. These details will be passed on to the Neurophysiologist (specialist doctor) who interprets and reports on the EEG after you have left the department. The electrodes will be applied to your child’s head as before. He/she will then be asked to lie down and close their eyes to encourage sleep. The room will be darkened and your child will be kept warm by a sheet or blanket.

How long will the test last?

Your child’s appointment will last approximately 1½ hours in total with the EEG recording itself taking approximately 45 minutes.

What else may be involved?

As with the routine EEG, your child may be asked to perform the activation procedures (the deep breathing and the flashing lights). Both these procedures are very useful for obtaining further information that does not show up when your child is simply resting. You may choose for your child not to have these carried out, in which case the rest of the test will be carried out as normal.

Are there any risks?

Sleep deprivation is also an activation procedure and all activation procedures carry a small risk or producing a fit in people who are prone to fits. It is important to remember that these activation procedures are far more likely to aid the doctor in reaching a diagnosis. If you are bringing your child by car and have also been sleep deprived we strongly advise that you do not drive because of the danger to yourself and the public. In this case please arrange for someone else to drive you or use public transport.

Are there any alternatives to sleep deprivation?

Melatonin

Melatonin may be prescribed instead or along with sleep deprivation. Melatonin is a naturally occurring hormone found in the pineal gland of the brain and is considered important in the production of sleep. We use a synthetic compound of melatonin that comes in the form of tablets or liquid. Melatonin be used instead of sleep deprivation to try and produce a natural daytime sleep so that a sleep EEG recording can be obtained. Melatonin does not produce heavy sedation and therefore it is not appropriate to use it for this indication (refer to EEG Guidelines for more information). If you have any questions about whether melatonin is appropriate for your child then please discuss with the EEG department or with your Consultant Neurologist.

How is melatonin given?

Melatonin is generally given in tablet or liquid form and is swallowed with a drink. The Melatonin

can also be dissolved in a drink if necessary. Melatonin takes about 20-60 minutes to work. It is

given just as the EEG recording starts or in come cases the child may be allowed to fall asleep

before the electrodes are applied. Melatonin is administered by a nurse in the EEG department but

the child does not have medical or nursing surveillance during the remainder of the test. After the

EEG test is over the child is woken and the electrodes removed. The EEG is then reported in the

usual way.

What happens if melatonin fails to produce sleep?

If sleep is not obtained during the EEG recording then you will be informed. Decisions about how

to proceed depend on the clinical scenario and the question that is being asked of the EEG test.

Consultant Neurologists are available to discuss individual cases if a sleep EEG cannot be obtained.

What happens after the test?

After the electrodes have been removed from your child’s scalp, you will then be free to go home. Your child may still feel sleepy so you should plan a restful day for him/her following the test.

You will not get the results of the test on the same day. The EEG will be analysed by the Clinical Physiologist, and reported by the Consultant. The EEG report will then be sent to the doctor or

Consultant who referred your child.