Fig. 4: Polysomnography findings.

Recording summary of a two-month-old infant with position dependent obstructive sleep apnea. The infant first slept supine followed by recording in a side position. Obstructive and mixed apneas occurred almost entirely in the supine-sleeping position during REM sleep. In the second horizontal panel, one vertical bar presents one event. Brown vertical shadow bars cover periods of wakefulness with unreliable signal recording. BP blood pressure. Values calculated from pulse transit time. EtCO₂ end-tidal carbon dioxide, Resp_freq breathing frequency, SpO₂ Desat pulse oximeter oxyhemoglobin desaturation ≥3%, TcCO₂ transcutaneous carbon dioxide.