Obstructive sleep apnoea in children — structured clinical encounter

Station brief (candidate)

You are the paediatric registrar in a general clinic. A 4-year-old boy is referred because he snores loudly every night, with his parents describing pauses in his breathing followed by gasping, and he sleeps restlessly with his neck extended. He is a mouth breather with large tonsils, his weight has drifted from the 50th to the 9th centile over the past year, and preschool report new hyperactivity and inattention. The team asks you to establish the diagnosis, order and interpret the investigations, plan treatment, and address the peri-operative and follow-up considerations. You have 12 minutes with the team and 5 minutes for examiner discussion. [1] [9]

Information available on request

• 4-year-old boy; loud snoring every night with witnessed apnoeas and gasping arousals; restless sleep with neck hyperextension and sweating; secondary enuresis has returned. [1]
• Daytime: hyperactive and inattentive at preschool, irritable, not overtly sleepy. [9]
• Examination: mouth breather with adenoidal facies and hyponasal voice, large obstructing tonsils; weight has fallen from the 50th to the 9th centile; blood pressure normal; no hepatomegaly or right heart signs. [1]
• Pediatric Sleep Questionnaire (on request): elevated, consistent with sleep-disordered breathing. [1]
• Nocturnal pulse oximetry (on request): repeated clusters of desaturation to the low 80s%. [7]
• Polysomnography (on request): obstructive apnoea-hypopnoea index of 12 per hour with associated desaturations — severe OSA. [1]

Tasks

1. Give the diagnosis and the features that support it, and explain why the growth faltering matters. [1]
2. Outline the investigations and what each contributes, including what to do if polysomnography is unavailable. [1] [7]
3. State the first-line treatment and the trial evidence for it. [3]
4. Describe the peri-operative considerations and who is at high risk. [1]
5. Describe the follow-up plan and what predicts residual disease. [6]

Marking anchors

Must-hit

• Diagnoses obstructive sleep apnoea from adenotonsillar hypertrophy on the basis of loud habitual snoring, witnessed apnoeas, restless sleep, mouth breathing with large tonsils, secondary enuresis, faltering growth and behavioural daytime symptoms; explains that OSA causes reversible failure to thrive through increased work of breathing and disrupted growth-hormone secretion. [1] [9]
• Names overnight polysomnography as the gold standard and nocturnal oximetry as the pragmatic rule-in alternative when it is unavailable, correctly stating that a positive clustered-desaturation trace rules in OSA but a normal result does not exclude it. [1] [7]
• States that adenotonsillectomy is first-line and cites the Childhood Adenotonsillectomy Trial's benefits on behaviour, quality of life and polysomnography, with catch-up growth expected after treatment. [3]

Merit

• Identifies the high-risk peri-operative airway (very young age, severe OSA) requiring monitored surgery, overnight admission and cautious opioid use; plans post-operative review with a repeat sleep study for severe disease; and names obesity, severe baseline disease and syndromes as predictors of residual OSA (Bhattacharjee). [1] [6]

Fail

• Reassures the family that the child is a benign snorer and arranges no investigation or treatment despite witnessed apnoeas and faltering growth. [1]
• Discharges a very young child with severe OSA as a routine day-case adenotonsillectomy without monitored recovery. [1]