Obstructive Sleep Apnoea

Question 1

Define Obstructive Sleep Apnoea

Answer 1

irregular breathing at night due to intermittent closure/collapse of the pharyngeal airway causing apnoeic episodes during sleep WITHOUT daytime sleepiness

Question 2

Define obstructive sleep apnoea syndrome

Answer 2

Recurrent episodes of complete or partial obstruction of the upper airway airway during sleep, causing apnoea (complete airflow obstruction with temporary absence or cessation of breathing) or hypopnoea (decreased airflow)

Question 3

What is the aetiology of obstructive sleep apnoea

Answer 3

Dynamic narrowing of the upper airway during sleep
This can be triggered by neuromuscular mechanisms within an anatomically small upper airway
Anatomical narrowing may be mediated by maxillomandibular anomalies or adenotonsillar hypertrophy (most common in children)
Increases in lateral pharyngeal, soft palatal and tongue tissue mass is commonly seen in obesity, which would also narrow the airway

Question 4

What are the risk factors for obstructive sleep apnoea

Answer 4

Obesity
Adenotonsillar hypertrophy
Craniofacial abnormalities e.g.
- Retrognathia (abnormal jaw positioning with mandible set back from the maxilla)
- Micrognathia (undersized lower jaw)
- Cleft palate
Neuromuscular disease e.g. cerebral palsy
Down’s syndrome, achondroplasia, Prader-Willi syndrome

Question 5

What is the epidemiology of obstructive sleep apnoea

Answer 5

Peak incidence between 2-8 years of age
Equal prevalence in boys and girls

Question 6

What are the symptoms of obstructive sleep apnoea

Answer 6

Night:
Loud snoring
Apnoeic episodes (episodic cessation of breathing terminated by a loud snore)
Gasping or choking during sleep
Poor sleep quality
Nocturnal enuresis
Restlessness and sudden arousals from sleep, laboured breathing, unusual sleep posture (for example with neck hyperextended)

Day:
Daytime somnolence or fatigue
Morning headache
Reduce cognitive performance, behavioural problems, hyperactivity
Impaired concentration, reduced school performance
Mouth breathing

Question 7

What are the signs of obstructive sleep apnoea on examination

Answer 7

General: Obese, Mouth breathing, Nasal speech
ENT: Maxillomandibular anomalies, Micrognathia, Retrognathia, Macroglossia

Question 8

What investigations should be done for obstructive sleep apnoea

Answer 8

Ask carers to record a video of sleep

STOP-Bang questionnaire: 8 items to assess snoring, sleeping, apnoea etc.
Epworth Sleepiness Scale: 8 items that assesses daytime sleepiness

Bedside: sats
Other:
- Polysomnography (PSG): monitors O2, sats, airflow + ECG/EMG/chest/abdo movements
- Portable multichannel sleep tests
- Awake or drug-induced sleep fibreoptic endoscopy

Question 9

What Polysomnography (PSG) suggests obstructive sleep apnoea

Answer 9

Occurrence of 15 or more episodes of apnoea or hypopnoea during 1 hour of sleep, on average, indicates significant OSA

Mild: AHI 5–14 per hour.
Moderate: AHI 15–30 per hour.
Severe: AHI more than 30 per hour.

Question 10

What is the management for obstructive sleep apnoea

Answer 10

Nasopharyngeal obstruction + regular snoring → referral to paediatric ENT (ideally within 4 weeks)
Congenital development disorder or associated condition or obesity → referral to paediatritian

Adenotonsillar hypertrophy → Adenotonsillectomy to correct the anatomic obstruction causing symptoms. This procedure is usually curative in children

Second line: CPAP therapy

Question 11

What are the complications of obstructive sleep apnoea

Answer 11

Behavioural problems
Irritability
Reduced concentration
Reduced school performance
Faltering growth (in severe cases)
Pulmonary hypertension
Nocturnal hypoxaemia

Question 12

What is the prognosis for obstructive sleep apnoea

Answer 12

In the majority of cases of uncomplicated OSAS, treatment with adenotonsillectomy resolves symptoms