TY - JOUR T1 - Forced Oscillation Technique calculates optimum EPAP as sleep stage and body position change JF - European Respiratory Journal JO - Eur Respir J DO - 10.1183/13993003.congress-2020.1276 VL - 56 IS - suppl 64 SP - 1276 AU - Chuck Cain AU - Sidney Cannon-Bailey AU - Jim Mckenzie AU - Michael Kissel AU - Bill Hardy AU - Parul Nisha Y1 - 2020/09/07 UR - http://erj.ersjournals.com/content/56/suppl_64/1276.abstract N2 - Rationale: Expiratory Flow Limitation (EFL) is present in some patients with COPD. EFL is correlated with dyspnea, and diminished exercise tolerance. The degree of EFL varies with body position, for example. In this study, EFL during sleep using a non-invasive ventilator (NIV) applying the Forced Oscillation Technique (FOT) was explored.Methods: An unreleased noninvasive ventilator (BiPAP A40, Philips Respironics, USA) in S/T mode, PEEP range 4 -20 cmH2O, and pressure support of 6 cmH2O was used with FOT to estimate EFL and automatically adjust PEEP (PEEPopt) overnight. Eight participants (mix of NIV naïve and hypercapnic NIV users) with COPD identified to have EFL were studied with overnight polysomnography (PSG). PEEPopt was analyzed in each sleep stage and body position.Results: Total sleep time averaged 237 minutes, average time in N1=38, N2=124, N3=30, and REM=45 minutes. There tended to be a negative correlation between sleep stage and PEEPopt (-0.23 overall) and a positive correlation with PEEPopt and body position (higher in supine, 0.31 overall). Figure 1 shows data for individual patients and a representation of sleep stage and body position with PEEPopt.Conclusion: PEEPopt was lower as patients entered deeper sleep stages and varied with body position. The variability of EFL and PEEPopt overnight based on sleep stage and body position show the need for auto-titrating PEEPopt to treat EFL through the night.FootnotesCite this article as: European Respiratory Journal 2020; 56: Suppl. 64, 1276.This abstract was presented at the 2020 ERS International Congress, in session “Respiratory viruses in the "pre COVID-19" era”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only). ER -