Objective To determine reference values for pulse oximeter saturation (SpO₂) 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 SpO₂ variables (eg, median SpO₂) 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 SpO₂ was 97.3% (1.4%). There were 36 (17%) subjects with desaturation events to <80% SpO₂ based on SIQ, and 26 (12%) based on SIQ+PW. Median desaturation event rate to <80% SpO₂/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% SpO₂ 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.