Polysomnography (sleep study)
Polysomnography (sleep study)
A polysomnogram (sleep study) is the gold-standard test for the investigation of breathing problems during sleep.
Key points to remember about polysomnography
- a polysomnogram (sleep study) is the gold-standard test for the investigation of breathing problems during sleep
- it requires attaching small sensors to your child's head, face and chest
- it takes 1 to 2 hours to place all the sensors but does not hurt
- your child will usually need to sleep the night with the sensors in place, either on a hospital ward or special sleep unit
- you stay with your child throughout the process - both to support your child and help staff keep the sensors in place
What is polysomnography?
A polysomnogram (also known as a sleep study) is the gold-standard test for the investigation of children or adults who have breathing problems during sleep (such as obstructive sleep apnoea).
It involves sleeping with multiple sensors (as many as 30) attached to the person's body. This provides information about the quality of sleep and can detect problems that occur with a person's breathing while they are asleep.
Sometimes abbreviated studies using fewer sensors (such as an 'oximetry' or a 'cardio-respiratory' study) may be adequate, avoiding the need for a full polysomnogram.
See the page about snoring or noisy breathing.
What happens during polysomnography?
A sleep study involves measuring your child's sleep and breathing patterns. This requires attaching small sensors to your child's head, face and chest. These sensors stick to the skin and are connected to monitors by thin wires. A sensor at the nose measures whether there are any pauses in your child's breathing and bands around the chest and tummy measure how hard your child is trying to breathe.
It takes 1 to 2 hours to place all the sensors but does not hurt.
Your child will usually need to sleep the night with the sensors in place, either on a hospital ward or special sleep unit or, in rare cases at home. An audio and video recording of their sleep will usually take place at the same time.
You stay with your child throughout the process - both to support your child and help staff keep the sensors in place.
While polysomnography doesn't hurt, some children find the sensors uncomfortable and young children may find them distressing. Like many tests in childhood, they can be a challenge to perform for both staff and family.
Sometimes doctors will ask for a finger prick blood test the following morning.
Nurses or sleep scientists will remove the sensors after your child has woken the next day.
Polysomnography provides a great deal of information about sleep and breathing and takes several hours to analyse fully. You may receive interim results the same day, but it may be a week or two before the study is fully analysed and reported.
How can you help prepare your child for polysomnography?
You can help prepare your child by explaining what is going to happen and reassuring them that you will stay with them while they have the test. It is really helpful if you can take something with you for your child to do while the sensors are being attached (such as a favourite toy or book or tablet activity). Taking their own pyjamas, a favourite pillow or blanket may make your child feel more relaxed when sleeping in a strange place. You can spend the night with your child, and this is recommended so that your child has the best possible sleep and doctors can get the most information from the test.
Are there any risks from polysomnography?
There is little risk involved. Very occasionally a child's skin may react to the tapes or sensors resulting in a short-term rash. Polysomnography itself is painless but may be uncomfortable and sometimes your child needs a blood test in the morning as part of the assessment.