Snoring and obstructive sleep apnoea

What are snoring and sleep apnoea in children?

When a child falls asleep, the muscles in the body relax. Relaxation of the muscles in the throat can narrow the breathing passage. For most children, there is still plenty of space to breathe easily.

Snoring is the sound generated by vibration of the relaxed muscles of the throat.

A majority of these children have ‘simple snoring’ — that is, they may snore heavily but it is not associated with significant blockage or obstruction to their breathing passages or disturbance in their sleep pattern.

A small number of children (just under 2 in 100) have obstructive sleep apnoea (OSA). This occurs when relaxation of the throat muscles leads to temporary blockage of the breathing passage (apnoeas). When this happens, the brain sends a signal to partly (or fully) waken the child, to allow the muscles to tense up and open the breathing passage so their breathing returns to normal. Once they fall into a deeper sleep, the muscles relax again leading to a cycle of sleep – obstruction – wake – normal breathing (often seen as a gasp for air).

Much less commonly, some children have periods where they have pauses in their breathing at night because the part of the brain that controls breathing is not working properly. This is called ‘central apnoea’, and is sometimes seen in children with medical conditions affecting the brain and nervous system.

What causes OSA in children?

Anything leading to narrowing of the upper breathing passage (airway) can lead to OSA.

Some of the risk factors are:

• enlarged adenoids or tonsils
• obesity
• changes in the head and face proportions (seen in some syndromes such as Down’s syndrome and achondroplasia)
• problems in the nervous system and muscle leading to low tone, such as in cerebral palsy
• metabolic syndromes, such as glycogen storage diseases

What problems can snoring and sleep apnoea cause?

Most of the problems related to snoring and sleep apnoea are a related to a disturbance in sleep which leads to a poor quality of sleep. Children may sleep for a good number of hours, but because of a poor quality of sleep this may not be enough to keep up with their development needs.

If severe, sleep apnoea can put strain on the heart that would need to work harder to pump blood.

The problems you may notice include:

• tiredness during the day
• difficulty waking up in the morning
• need for naps during the day
• hyperactivity or poor behaviour
• poor concentration
• lack of energy
• irritability
• poor appetite
• poor weight gain
• bed wetting

Some children may have sleep apnoea without any obvious day time symptoms.

More recently it is now understood that snoring without sleep apnoea can also suffer from consequences of disturbed sleep, including poor concentration and mild educational difficulties.

How can I tell if my child has sleep apnoea?

The most common symptom you may notice is significant snoring.

Additionally, you may notice some (or all) of the following:

• breath-holding
• gasping for air
• frequent waking from sleep
• sweating
• unusual head positioning such as head and neck stretched out (that may help to open the airway better)
• sucking-in of the chest or at the front of the neck (a sign of increase in their work of breathing)

It is helpful to try and record a video of your child sleeping if you notice one of the above, which can help your doctor in making the diagnosis.

How will my doctor make the diagnosis of sleep apnoea?

In clinic

With some experience it is possible for doctors to make the diagnosis by taking a good history and examining your child in clinic. A video of your child sleeping can be very helpful.

For some children with mild symptoms, or those with severe symptoms and complex medical problems, your doctor may consider sleep testing to help confirm the diagnosis and check the severity of sleep apnoea.

Sleep testing

Oxygen level monitoring (overnight oximetry)

This is a simple sleep study that can often be done at home. It uses a simple finger probe connected to a machine that records your child’s oxygen levels. This data is then analysed by the sleep team. Drops in your child’s oxygen levels (desaturations) during sleep are often a marker of sleep apnoea.

This is a useful screening tool, and an ‘abnormal’ study, with multiple desaturations, can confirm that there is a problem.

On the other hand, a ‘normal’ study, may miss some children with mild sleep apnoea. In such cases, the study results are usually interpreted along with the child’s history and clinical findings.

Complex sleep study (polysomnography or PSG)

A PSG is a more detailed sleep study done over one or two nights that usually requires for your child to be admitted to the Sleep Department. It involves monitoring a number of different things during sleep, including:

• oxygen and carbon dioxide levels
• heart beat
• blood pressure
• air flow at the nose or mouth
• leg and body movements
• brain activity (EEG) in some cases

This test provides more detailed information about your child’s sleep, and is usually reserved for either very young children or those with complex medical problems.

The main limitation of all sleep testing is that sleep apnoea can fluctuate and these tests provide a ‘snapshot’ of your child’s sleep, which may not be necessarily representative of your child’s average sleep.

How can sleep apnoea be treated?

Treatment for snoring and sleep apnoea depends on the underlying problem, and needs to be individualised to each child.

A number of children may have short periods of snoring and sleep apnoea associated with nose and throat infections, with temporary enlargement of tonsils and adenoids and a blocked nose. If the sleep returns to normal after the infection resolves then usually no treatment is required.

If the problems are long standing, than there are some medical and surgical options for treatment.

Conservative or medical treatment

A number of children with sleep apnoea will eventually grow out of their symptoms as their body grows and their throat enlarges, while their tonsils and adenoids shrink. It may be challenging knowing when this improvement will happen, but often a period of waiting of up to 6 months may be reasonable to allow for this, depending on how bad the symptoms are.

Sometimes the reason for the blockage or obstruction may be due to swelling or inflammation of the lining of the nose, often related to allergies. In such situations a combination of a non-drowsy anithistamine by mouth and a steroid spray to the nose can help reduce the swelling in the lining of the airway and improve sleep quality.

Surgical treatment

In a majority of children, sleep apnoea is due to enlargement of the tonsils, the adenoids or both. If there has been no improvement with conservative treatment, then surgery is usually effective in improving their symptoms, even in children with complex medical problems that may contribute to their sleep apnoea.

In infants and very young children, removing just the adenoids (‘adenoidectomy’) may be enough to improve symptoms. In older children and when the tonsils are enlarged, removal of both tonsils and adenoids (‘adenotonsillectomy’) may be necessary. Deciding which procedure is needed would be tailored to each child’s needs.

Other treatments

Some children may continue to have symptoms of sleep apnoea, even after removing adenoids and tonsils. Further treatment may need to be considered on an individual basis, with involvement of different teams of specialists. This would include children’s lung (respiratory) specialists who will usually help organise a complex sleep study and may consider support for breathing at night with a mask secured over the nose, the mouth or both. This mask is connected to a machine that delivers air under pressure to keep their breathing passage open. This is called ‘continuous positive airway pressure ventilation’ or CPAP.