Objective: To provide reference values for pulse oximeter saturation (SpO(2)) in primary school children, measured at home during sleep.
Methods: Recordings of SpO(2) and signal quality from 100 children were randomly selected from a larger population-based sample intended to study the prevalence of sleep-disordered breathing. Recordings were analyzed for the duration of artifact-free recording time (AFRT), minimum SpO(2) (SATmin) and median SpO(2) (SAT(50)), the SpO(2) below which the child spent 5% of AFRT (SAT(5)), and the SpO(2) below which the child spent 10% of AFRT (SAT(10)). In addition, the time in seconds with SpO(2) <or= 90% per hour of AFRT (TI(90)) was calculated, as were the number of falls in SpO(2) by >or= 4% per hour of AFRT (DI(4)), the number of falls in SpO(2) to <or= 90% per hour of AFRT (DI(90)), and the number of falls in SpO(2) to <or= 92% per hour of AFRT (DI(92)).
Results: Ten recordings had to be excluded because of insufficient AFRT (< 5 h). Mean age of the remaining 90 children (54 girls) was 9.3 years (SD, 0.6). Median (range; fifth centile) values for SATmin, SAT(5), SAT(10), and SAT(50) were 93% (76 to 97; 87.5), 97% (88 to 99; 95), 97% (89 to 99; 96), and 98% (94 to 100; 97). Median values (range; 95th centile) for TI(90), DI(4), DI(90), and DI(92) were 0.0 s (0.0 to 5.8; 1.6), 0.8 (0.0 to 6.1; 3.9), 0.0 (0.0 to 1.2; 0.2), and 0.0 (0.0 to 2.0; 0.6).
Conclusion: Baseline SpO(2) values < 97% were uncommon in these children, as were intermittent desaturations to <or= 90%. These data may serve as a basis for the interpretation of clinical recordings of SpO(2) in children referred for sleep-related breathing disorders.