The impact of central and obstructive respiratory events on cerebral oxygenation in children with sleep disordered breathing

Both central and obstructive respiratory events are features of sleep disordered breathing. The repetitive hypoxia associated with obstructive events is believed to underpin the adverse neurocognitive and cardiovascular sequelae of this disorder, however whether central events contribute to this has not been investigated. To compare changes in cerebral and peripheral oxygenation, blood pressure and heart rate, associated with central and obstructive events in children aged 3-6 and 7-12 years. Sixty children referred for suspected sleep disordered breathing underwent overnight polysomnography. Beat-by-beat analysis determined changes from baseline in cerebral oxygenation, peripheral oxygen saturation, fractional tissue oxygen extraction, pulse transit time (a surrogate measure of blood pressure change), and heart rate, associated with central and obstructive respiratory events, during NREM and REM sleep. Eight hundred ninty-two events were analyzed: 493 central and 399 obstructive. Central events had a greater % change from baseline in cerebral oxygenation and heart rate nadir compared with obstructive events and these were greater in NREM compared with REM sleep. The 3- to 6-year-old children experienced a greater % change in TOI compared with the 7-12 year olds, while % change in heart rate was greater in 7-12 year olds. Central respiratory events had similar falls in cerebral oxygenation and heart rate to obstructive events and should be considered when examining the sequelae of sleep disordered breathing, particularly as central events are common in children with sleep disordered breathing.