RT Journal Article SR Electronic T1 A Hands-free, Oral, Positive Expiratory Pressure Device for Exertional Dyspnea and Desaturation in COPD JF Respiratory Care FD American Association for Respiratory Care SP respcare.10278 DO 10.4187/respcare.10278 A1 Muhammad Ahsan Zafar A1 Ashley Cattran A1 Rachel Baker A1 Roman Jandarov A1 Ralph J. Panos YR 2022 UL http://rc.rcjournal.com/content/early/2022/09/23/respcare.10278.abstract AB