Copd_a_289755 771..781

1Cologne Merheim Hospital, Department of Pneumology, Kliniken der Stadt Köln gGmbH, Witten/Herdecke University, Cologne, Germany; 2Department of Neurology and Neurophysiology, Helios Hospital Wuppertal, Witten/Herdecke University, Wuppertal, Germany; 3Praxis Pneumologie Solln, Munich, Germany; 4Department of Pneumology, University Medical Hospital, Freiburg, Germany; 5Clinical Trials Unit, Medical Center – University Medical Hospital, Freiburg, Germany Purpose: The impact of oronasal and nasal masks on the quality of nocturnal non-invasive ventilation (NIV) needs to be clarified. This trial was designed to compare the impact of oronasal and nasal masks on the objective quality and subjective acceptance of nocturnal NIV in COPDpatients. Patients and Methods: In a randomized crossover trial, 30 COPD-patients with wellestablished high-intensity NIV (mean inspiratory/expiratory positive airway pressure 26±3/5 ±1 cmH2O, mean respiratory back-up rate 17±1/min) were ventilated for two consecutive nights on oronasal and nasal masks, respectively. Results: Full polysomnography, nocturnal blood gas measurements, and subjective assessments were performed. There was a tendency towards improved sleep efficiency (primary outcome) when an oronasal mask was worn (+9.9%; 95% CI:-0.2%-20.0%; P=0.054). Sleep stages 3/4 were favored by the oronasal mask (+12.7%; 95% CI: 6.0%-19.3%; P=<0.001). Subjective assessments were comparable with the exception of items related to leakage (P<0.05 in favor of nasal masks). The mean transcutaneous PCO2 value for oronasal masks (47.7±7.4 mmHg) was comparable to that of nasal masks (48.9±6.6 mmHg) (P=0.11). There was considerable diversity amongst individual patients in terms of sleep quality and gas exchange following mask exchange. Subjective mask preference was not associated with sleep quality, but with nocturnal dyspnea. Over 40% of patients subsequently switched to the mask that they were not previously accustomed to. Conclusion: In general, oronasal and nasal masks are each similarly capable of successfully delivering NIV in COPD-patients. However, the individual response to different interfaces is extremely heterogeneous, while subjective mask preference is independent from objective measures, but associated with dyspnea. Trial Registration: German Clinical Trials Registry (DRKS00007741).