How to interpret polysomnography.

A 5-year-old child presents to a paediatric clinic with their parents because of concerns about snoring, which is loud, every night and associated with respiratory pauses. This has been present for 6 months. Can clinical evaluation diagnose sleep-disordered breathing in children or are further investigations required? Should further investigations include oximetry or polysomnography? If a polysomnogram is performed, how are the results interpreted? In this paper we describe the indications for polysomnography, outline the parameters measured and decode a clinical polysomnography report.