EVALUATION OF RESPIRATORY SLEEP EVENTS USING CHILDHOOD PULSE TRANSIT TIME

摘要

Pulse transit time (PTT) is a non-invasive measure and has shown potential to estimate breathing effort variations in response to involuntarily changes of the upper airway in adults during sleep. The objectives of this study were to assess the capability of PTT to classify respiratory sleep events as either central or obstructive in nature and its sensitivity to detect both apnoeas and hypopnoeas. 291 respiratory events occurred in 24 routine overnight polysomnographic (PSG) studies performed on children (19 male and 5 female, mean age 6.7years). PTT measurements were evaluated against the corresponding PSG results pre-scored by 2 blinded observers. Obstructive events showed a mean change of 5.35% (p < 0.05), with ±11.54ms standard deviation (SD) and maximal change of 12.94% (p < 0.05) from baseline PTT value during tidal breathing. Central events showed a mean 1.42% (p > 0.05) change, with ±3.00ms SD and maximal change of 1.98% (p > 0.05). PTT was able to categorise central and obstructive respiratory events accordingly, including hypopnoeas. Hence, PTT shows promises to differentiate respiratory events accordingly in absence of motion artefacts and can be a useful tool in a simplified ambulatory screening system for children for sleep-disordered breathing investigation.