SUNDAY,SEPTEMBER 25 TH 2011 155. Advances in long-term noninvasive positive pressure ventilation 1430 Respiratory mechanical and cardio-vascular changes during non invasive ventilation in stable COPD patients with chronic hypercapnic respiratory failure: High intensity ventilation vs low intensity ventilation Jozsef Lukacsovits 2 , Annalisa Carlucci 1 , Nicholas Hill, Piero Ceriana 1 , Lara Pisani, Annia Schreiber 1 , Paola Pierucci 1 , Andras Lorx 2 , Gyorgy Losonczy 2 , Stefano Nava 3 . 1 Department of Respiratory Rehabilitation, Fondazione Salvatore Maugeri, Pavia, Italy; 2 Department of Pulmonology, Semmelweis University Budapest, Budapest, Hungary; 3 Respiratory Intensive Care Unit, Azienda Opedaliera Universitaria Sant’ Orsola-Malpighi, Bologna, Italy In a subgroup of stable COPD patients with chronic hypercapnic respiratory failure (HRF) the use of conventional NPPV (Li-NPPV), can improve pulmonary function, gas exchange, and health related quality of life. High-intensity positive pressure ventilation (Hi-NPPV) with higher IPAP (28 cmH20) and respiratory rate (20/min) were recently adopted in order to achieve maximal PaCO2 reduction and has been shown to better improve diurnal blood gas during spontaneous breathing (SB), compared to Li-NPPV. NPPV can provoke alterations in intrapleural pressure and lung volume, which influence the cardio-vascular performance. Our study evaluates the respiratory mechanical (RM) and cardio-vascular (CV) effects of Li-NPPV and HI-NPPV, in 15 stable COPD patients with HRF. We measured the RM and blood gas parameters, in addition non-invasive measurement of CV parameters was per- formed. The data were reported as mean ±SD, and where compared with repeated measures ANOVA. Significant (sgn) increases were observed in pleural pressure, decrease in tans-diaphragmatic pressure and minute diaphragmatic pressure-time product (SB: 323±149; Li-NPPV: 132±139; Hi-NPPV: 40±69 cmH2O·s/min). The PaCO2 showed a sgn. decrease and the pH a sign. increase during either modalities of NPPV. Significant reduction were detected in arterial blood pres- sure, stroke volume, cardiac output (SB: 5.5±1.14; NPPV: 4,7±0.98; Hi-NPPV: 4.00±0.96 l/min) and oxygen transport. The long-term effects of this RM and CV changes are uncertain, accordingly further long-term studies are needed to determine its effect on survival. 1431 Lobar airway resistance and tissue stiffness in hypercapnic COPD patients eligible for NIV treatment Vos Wim 1 , Lieve De Backer 2 , Cedric Van Holsbeke 1 , Jan De Backer 1 , Denise Daems 2 , Wilfried De Backer 2 . 1 Respiratory, FluidDA nv, Kontich, Belgium; 2 Respiratory Medicine, University Hospital Antwerp, Edegem, Belgium Introduction: The internal airflow redistribution under non-invasive ventilation (NIV) is dependent on lobar airway resistance (Raw) and tissue stiffness (S). This study aims to calculate lobar R and S using functional imaging (FI) updated with computational fluid dynamics (CFD). Methods: 20 persistent hypercapnic COPD GOLD III patients, eligible for NIV treatment, undergo a low dose CT scan at FRC and TLC. From these scans airway tree and lobar expansion (=internal flow distribution) are obtained. Also a simultaneous respiratory flow and esophageal pressure (peso) measurement is performed. CFD calculations using the 3D model, measured flow rates and internal 254s Oral Presentation Room 3.2 - 14:45-16:45 Abstract printing supported by . Visit Chiesi at Stand D.30