A Meta-analysis of Clinical Screening Tests for Obstructive Sleep Apnea

Abstract

OBSTRUCTIVE sleep apnea (OSA) affects 2–4% of the population1 in the United States and is now considered a significant risk factor for perioperative morbidity and mortality.2,3 The risks of OSA in the general population are well known and include hypertension,4 coronary artery disease,5,6 stroke,7 pulmonary hypertension,8 sudden cardiac death,9 and deep vein thrombosis,10 to name a few that directly impact on perioperative outcome. Overnight polysomnography is the standard for diagnosis of OSA, but its value in the management of patients scheduled to undergo surgery is reduced by significant issues with resource availability.11 Full polysomnography involves an overnight stay in a designated sleep laboratory with multichannel monitoring to measure electro-oculogram, chin and leg electromyography, electro-oculography, chest and abdominal respiratory effort, nasal airflow via a thermistor and/or nasal cannula, oxygen saturation, and heart rate monitoring, in addition to several sleep architecture measures. Traditionally, the apnea-hypopnea index (AHI) or the respiratory disturbance index has been used as a measure of the presence of OSA and its severity. Accepted diagnostic thresholds for OSA have varied between AHI values of 5 or more per hour1,12 and 10 or more per hour.13