Abstract â–¡ 175

Is polysomnography (PSG) needed for all children suspected of OSA? This report assesses the potential utility of nocturnal oximetry for diagnosing pediatric OSA. The PSG determined mixed/obstructive apnea/hypopnea index (MOAHI) ≥ 1/hr defined OSA. A physician, blinded to clinical and PSG information, classified each oximetry as normal, inconclusive, or abnormal. It was then compared to the PSG diagnosis. Each oximetry was classified using the following criteria: 1) a desaturation was defined as a decrease in SaO2 of ≥ 4% ;2) an abnormal oximetry had ≥ 3 desaturation clusters and ≥ 3 desaturations < 90%; 3) a normal oximetry had no desaturation clusters and no desaturation < 90%;. Results: Of 485 patients, 349 were referred for evaluation of OSA, were eligible for inclusion in the study, and had complete data available. Oximetry trend and events graphs were classified as abnormal in 93, normal in 95, and inconclusive in 161. The positive predictive value (PPV) of oximetry was 97% (90/93); the sensitivity of oximetry was only 43% (90/210). A normal or inconclusive oximetry did not rule out OSA: negative predictive value (NPV) of oximetry was 53%. Amongst 257 patients without major medical diagnoses other than adenotonsillar hypertrophy (ATH), oximetry had a PPV of 100%, and a sensitivity of 43%; 92 patients with other medical problems, oximetry had a PPV of 86%, and a sensitivity of 42.%. Conclusion: For a child suspected of having OSA, an abnormal nocturnal oximetry tracing has at least a 97% PPV. Oximetry could: 1) be the definitive diagnostic test for straightforward OSA due to ATH or 2) quickly and inexpensively identify children with a history suggesting sleep disordered breathing who would require PSG to elucidate the type and severity. (Figure)

figure 1