ABR Hearing Test Under Sedation for Babies and Children

Children’s Services Colchester Hospital Children’s Ward Tel: 01206 746208 or 746209

Children’s Elective Care Unit Tel: 01206 744237

More Information

ABR stands for auditory brainstem response, which is a test used to estimate a child’s hearing.

Further testing under sedation is needed to ascertain if your child has a hearing loss.

You will be asked to attend the Children’s Elective Care Unit so that your child can be prepared for the test. Your appointment letter will give you details of times and there is a map on the back page of this leaflet.

On arrival you will meet your nurse, who will explain what will happen during the procedure. A doctor will see you and your child to ensure he or she is fit for sedation. They will discuss consent with you.

By law we must obtain written consent before some procedures. Staff will explain all the risks, benefits and alternatives before they ask you to sign a consent form. If you are unsure about any aspect of the proposed treatment, please do not hesitate to ask to speak to the doctor or nurse who is caring for your child.

Sedative drugs are used to induce a deep sleep so that a planned medical procedure can be carried out.

To record the electrical response we need your child to be sleeping soundly, as the ear’s response to a sound is very tiny and can easily be hidden by the movement of nearby muscles.

In a very small number of children, sedation may not be effective in inducing sleep. If this occurs it will not be possible for the procedure to be carried out and we will discuss with you the options for alternative investigations.

It is important that your child does not have anything to eat or drink before the sedation is given. Sedation is more effective if it is given on an empty stomach. It is essential that you do not give your child food or milk drinks up to six hours before sedation. They can drink clear fluids (water- based drinks like weak squash), however, up to one hour beforehand. Babies may have breast milk up to four hours before sedation. If you do not follow these instructions your child’s procedure may need to be cancelled.

Your child is given medicine to drink about one hour before the procedure, which induces sleep. It is important that the whole dose is taken for it to be effective. The nurse will support you in helping your child to swallow the medicine.

The nurse will check your child’s breathing and use a machine to measure oxygen levels. This will continue until your child wakes up. Most children wake up after several hours but others need longer to recover. They may feel drowsy and sleepy for several hours.

When your child begins to wake up, initially he or she may be unsteady on his or her feet and will require supervision.

Children are generally sleepier than usual for up to 24 hours after sedation, so please arrange to take your child home by car or taxi.

If your child is not feeling nauseous, offer something to eat.

Milk may be offered if your child does not feel sick or has not vomited.

If your child is difficult to wake or you are worried about how sleepy they are, place them on their side and ring your GP for advice.

Do not let your child ride a bike, go swimming or do sports for 24 hours. Do not send your child to nursery or school for 24 hours.

If your child is on any medication, continue to give this as normal.

Your child may have mood changes, which can make him or her irritable. This is temporary. Keep a close watch until he or she is back to normal.

Too much sedation may affect your child’s breathing. For this reason every child is weighed and the dose of medicine is calculated for your child’s individual requirements.

Your child is also at risk of injury from falling as he or she may be unsteady on his or her feet when they wake up. Your child will need careful supervision, therefore, immediately after the procedure and for the following 24 hours.

The audiologist will put three sticky jelly pads on your child’s head (one on the forehead and one behind each ear). The pads are attached to recording wires to record the electrical signals from the ear being tested. The sounds will be presented to your child’s ear through small earplugs to test each ear separately. The test takes 1-2 hours to complete.

To help us with the placement of the sticky pads please avoid using any oils or lotions at bathtime before your appointment.

Please do not bring any other children with you to this appointment, due to the length of time it will take and the need for quiet while testing.

Your child must stay on the Elective Care Unit until he or she is fully awake and has had something to eat and drink. This will be at least two hours after the sedation is given.

The audiologist may tell you about the recording of the hearing test when it is finished. Your consultant will discuss the results at your next appointment.

If you have any further concerns or questions, please contact us on 01206 744237.

Wristbands are used to identify hospital inpatients. When your child is in hospital it is essential that he or she is given and wears their wristband, which carries his or her name, date of birth, NHS number and hospital number. This ensures that staff can identify your child correctly and give them the right care.

When your child attends hospital you will be asked for his or her NHS number and other information, such as your address.

Please be patient with this procedure as it is to ensure our records are kept up to date and to protect your child’s safety.

If you do not know his or her NHS number, please don’t worry, he or she will still receive care.

To find out how to give us feedback on your visit or healthcare experience, please visit and search for ‘PALS’ or ‘Your views matter’, or speak to a member of staff on the ward or department you are in.