Obstructive Sleep Apnoea

Question 1

What is obstructive sleep apnoea (OSA)?

Answer 1

Obstructive sleep apnoea (OSA) presents as snoring associated with periods of ineffective breathing of >2 breaths (e.g. breathing at 20/min, this would be 6s).

Question 2

What is the commonest causes of OSA?

Answer 2

The commonest causes of OSA are upper airway obstruction (UAO) due to adenotonsillar hypertrophy or obesity.

Question 3

What is central apnoea?

Answer 3

Central apnoeas are rare and defined by pauses in breathing of >20s in an otherwise well child. They are usually associated with a significant CNS disorder (acute injury or long-standing neurodisability). Very rarely caused by central hypoventilation syndrome.

Question 4

What is OSA syndrome (OSAS)?

Answer 4

OSA syndrome (OSAS) may be due to tonsillar/adenoidal hypertrophy, obesity, macroglossia, or micrognathia. OSAS can cause metabolic, cardiac, and neurocognitive disorders in children if left untreated.

Question 5

What are the clincial features of OSA?

Answer 5

• Snoring and sleep disturbance
• Daytime sleepiness or inattention
• Enuresis
• Only ~15% of snoring children have significant airway obstruction

Question 6

What signs can be found on examination of a child with OSA?

Answer 6

Findings commonly found on physical examination include:

• Symptoms of UAO and OSAS are more likely to be due to adenoidal hypertrophy, rather than just tonsillar hypertrophy
• Middle ear infection and chronic effusion
  
  • These are features associated with adenoidal hypertrophy
• Mouth breathing
  
  • Leading to dry mouth and cracked lips
• FTT and behavioural problems

Question 7

What investigations should be ordered for OSA?

Answer 7

A thorough history and examination should identify children who need further treatment. However, consider the following useful tests:

• Sleep study
• CXR
• ECG

Question 8

Briefly describe the role of sleep study in diagnosing OSA

Answer 8

This could include just overnight SpO2, but to diagnose impaired gas exchange, transcutaneous CO2measurement is necessary as well. In cases of diagnostic difficulty, more extensive polysomnography may be needed, mainly to differentiate OSA from central sleep apnoea.

Question 9

Briefly describe the role of CXR and ECG in diagnosing OSA

Answer 9

To look for secondary right heart cardiac consequences of UAO (e.g. RVH).

Question 10

Briefly describe the management of OSA

Note: medical and surgical

Answer 10

• Medical:
  
  • CPAP for a select group because of often poor adherence
  • Weight loss is recommended for all obese patients
• Surgery
  
  • Adenotonsillectomy (when evidence of airway obstruction)
  • Uvulopalatopharyngoplasty.
  • Tracheostomy (very rare)