Oximetry for suspected obstructive sleep apnea-Does removal of awake data affect the result?

Frequency of dips below 90% on overnight oximetry can be used to estimate severity of obstructive sleep apnea (OSA) in children. Movement can result in artifact on oximetry recordings. Clinicians may therefore be tempted to remove periods of wakefulness from the recording to improve accuracy, but removal of such periods of potential artifact is time consuming. The aim of this study was to determine whether removing periods of wakefulness had a significant impact on analysis of overnight oximetry. Children aged 2-18 years (N = 108) with suspected OSA underwent overnight simultaneous oximetry and actigraphy at home on a single night. Actigraphy defined awake periods were "trimmed" from the oximetry data and oximetry variables compared between full and trimmed analysis. There was a statistically but not clinically significant difference between the full and trimmed data for mean SpO2 , minimum SpO2 , 4% desaturation index, and 3% desaturation index (all P < 0.05). There was no difference between the two analyses for median SpO2 or the frequency of dips below 90%, 85%, or 80%. In conclusion, removal of periods of wakefulness at the start and end of overnight oximetry recordings does not affect the result in the context of testing for suspected OSA in children. Pediatr Pulmonol. 2016;51:1409-1413.