Gas exchange parameters for the prediction of obstructive sleep apnea in infants

Study Objectives: Sleep laboratory polysomnography is the gold standard for obstructive sleep apnea (OSA) diagnosis in infants, but its access remains limited. Oximetry-capnography is another simple and widely used tool that can provide information on the presence of desaturations and alveolar hypoventilation. However, its reliability is debated. This study aimed at examining its use in determining OSA severity in infants. Methods: This retrospective study was conducted in a sleep unit in a tertiary hospital in infants < 4 months old with clinical signs of OSA or Pierre Robin sequence who underwent a 1-night polysomnography coupled with oximetry-capnography. Results: Among the 78 infants included (median [interquartile range] age: 61 [45-89] days at polysomnography), 44 presented with Pierre Robin sequence and 34 presented with isolated airway obstruction. The clinical, sleep, and respiratory characteristics were not significantly different between the 2 subgroups. In the entire cohort, 63.5% had severe OSA. The median obstructive apnea-hypopnea index was 14.5 (7.4-5.9) events/h, peripheral oxygen saturation (SpO(2)) was 97.4% (96.5-98.1%), and transcutaneous carbon dioxide pressure (PtcCO(2)) was 41.1 mmHg (38.3-44.9). The optimal threshold to predict an obstructive apnea-hypopnea index > 10 events/h was 6 events/h for an oxygen desaturation index >= 3% (sensitivity, 95.7%; specificity, 51.9%) and 2 events/h for an oxygen desaturation index >= 4% (sensitivity, 95.7%; specificity, 48.1%). Conclusions: Whereas transcutaneous capnography does not appear to be sufficient in predicting severe OSA in infants < 4 months old with Pierre Robin sequence or clinical signs of OSA, oximetry may be a useful alternative for the screening of severe OSA in infants in the absence of polysomnography.