Objective: To determine reference values for pulse oximeter saturation (SpO(2)) variables and desaturation event indices in healthy term neonates during their first 5 days of life, and to compare two definitions for the identification of desaturation events.
Design: Observational study (case series). Setting Maternity ward, Department of Neonatology, University Children's Hospital, Tuebingen, Germany.
Patients: 209 healthy term neonates (50% boys), median (minimum-maximum) age 2 (0-5) days.
Main outcome measures: SpO(2) variables (eg, median SpO(2)) and desaturation events obtained by motion-resistant pulse oximetry (VitaGuard 310; Getemed, incorporating Masimo SET). Desaturation events were identified based either on a good signal quality (SIQ) provided by the device or on the combination of a good SIQ and an undisturbed pulse waveform (SIQ+PW). Desaturation event indices were calculated as desaturation events divided by hour of artefact-free recording time.
Results: The mean (SD) of the obtained median SpO(2) was 97.3% (1.4%). There were 36 (17%) subjects with desaturation events to <80% SpO(2) based on SIQ, and 26 (12%) based on SIQ+PW. Median desaturation event rate to <80% SpO(2)/h (75th centile; 95th centile; maximum) was 0 (0; 0.6; 2.3) based on SIQ, and 0 (0; 0.4; 1.7) based on SIQ+PW.
Conclusions: Desaturation events to <80% SpO(2) were rare in our sample of healthy term neonates during their first 5 days of life. Analysis of SIQ alone could be a quick and simple alternative to traditional analysis of PW. The presented reference values may be used for clinical decision making.