Long-term reduction of hyperinflation in stable COPD by non-invasive nocturnal home ventilation

Objective: The rote of non-invasive positive pressure ventilation (NPPV) in stable COPD with chronic ventilatory failure remains controversial. The impact of long-term home nocturnal NPPV treatment on deflation has not yet been evaluated in detail. Methods: Retrospective explorative study of 46 patients with stable COPD undergoing NPPV treatment. Effects of NPPV on bodyplethysmographic parameters, blood gas tensions and inspiratory muscle function after 6.2 ( +/- 1.7) and 12.7 ( +/- 2.1) months of treatment. Further, evaluation of 1-year survival, compliance and ventilation parameters. Results: One-year survival was 89.1%. The effectiveness of ventilation was proven by a significant reduction in nocturnal and daytime POCO2. We observed a decrease in the ratio of residual volume (RV) to total lung capacity (TLC) on the average of 5.2 +/- 9.8% (or 15.2 +/- 29.7% pred.; P < 0.01) at six and 3.9 +/- 9.0% (or 12.9 +/- 18.6% pred.; P < 0.001) at 12 months. As a consequence, we found significant improvements in inspiratory capacity (IC), vital capacity (VC) and forced expiratory volume in one second (FEV1). For patients with the most severe hyperinflation (RV/TLC > 75%), we found a significant positive correlation between inspiratory positive airway pressure (IPAP) and reductions in PaCO2 (r = 0.56; P < 0.05) and RV/TLC (r = 0.50; P < 0.05). Conclusions: In severe hypercapnic stable COPD long-term nocturnal NPPV can reduce hyperinflation with sustained improved daytime blood gas parameters. (c) 2005 Elsevier Ltd. Alt rights reserved.