Nocturnal oximetry in children with obstructive lung disease or sleep‐disordered breathing

Abstract Objectives Although progress has been made in the standardized interpretation of nocturnal oximetry in children with obstructive sleep‐disordered breathing (SDB), no evidence exists on oximetry abnormalities in other respiratory disorders. We aimed to compare obstructive lung disease (OLD) and SDB regarding nocturnal oximetry parameters. Methods We analyzed oximetry recordings from children with (i) OLD (obliterative bronchiolitis; cystic fibrosis); (ii) snoring and adenotonsillar hypertrophy (SDB); and (iii) no respiratory disorder (controls). The three groups were compared regarding: (i) oxygen desaturation of hemoglobin index (SpO 2 drops ≥3%/h‐ODI3) and (ii) basal SpO 2 (average SpO 2 between SpO 2 drops). The associations of oximetry parameters (natural logarithm) with study group were tested using linear regression including age as covariate. Results Data of 16 subjects with OLD (median age: 7.3 years; Q25, Q75: 5.4, 12), 22 children with SDB (6.3 years; 4, 9) and 22 controls (6.8 years; 5.6, 10.3) were analyzed. Children with OLD or SDB had significantly lower basal SpO 2 than controls (91.9% [90.8, 93.4] vs 96.3% [96, 97.4] vs 97.6% [97.1, 97.9]; P < 0.01). No subjects in the SDB or control groups had basal SpO 2 < 95%. Children with SDB had significantly higher ODI3 than children with OLD or controls [8.4 episodes/h (6.2, 16.6) vs 4.4 episodes/h (3.6, 6.6) vs 2 episodes/h (1.3, 2.7); P < 0.01]. OLD had the greatest negative effect on basal SpO 2 ( R 2 = 0.62; P < 0.001) and SDB the greatest positive effect on ODI3 ( R 2 = 0.34; P < 0.001). Conclusion OLD is associated mostly with reduced basal SpO 2 , whereas SDB is characterized by elevated ODI3.