0894 COMPARISON OF OVERNIGHT OXIMETRY DOWNLOAD WITH POLYSOMNOGRAPHY IN CHILDREN

Abstract

Introduction: The diagnosis of obstructive sleep apnoea (OSA) in children is challenging given the high prevalence (2–3%), the significant associated morbidity and the resource intensity of the Polysomnography (PSG) which remains the gold standard. The limited availability of PSG often results in a delay in diagnosis and management of significant OSA. The aim of this study is to evaluate the reliability of the overnight oximetry download as a screening tool for the diagnosis of OSA in children. Methods: A retrospective analysis of all children with clinical suspicion of OSA who underwent an overnight oximetry download and a subsequent PSG in a tertiary Paediatric Hospital from January 2014 to April 2016. The oximetry was reported based on McGill Scoring System and the diagnosis of OSA was based on mixed obstructive apnoea hypopnoea index (MOAHI). Results: During the study period, 110 patients had overnight oximetry download as well as PSG. Sixty-one children (56%) had normal, 30 (27%) had mildly abnormal and 19 (17%) had moderately/severely abnormal oximetry. Sixty-four percent of children with normal oximetry did not have OSA on PSG. Of the children with severely abnormal oximetry, 100% had severe OSA on PSG. The overall sensitivity and specificity of oximetry for identification of OSA were 63% and 78% respectively. The overall positive and negative predictive values (PPV and NPV) were 78% and 64%, respectively. The sensitivity and specificity of moderate/severe abnormal oximetry for diagnosis of moderate/severe OSA were 59% and 100%, respectively. PPV and NPV of moderate/severe abnormal oximetry were 100% and 78%, respectively. Conclusion: Children with moderate/severe abnormal oximetry do not need a PSG to diagnose OSA. They can be treated based on the oximetry result. However, a normal oxim