Nasal ventilation in COPD exacerbations: early and late results of a prospective, controlled study.

Noninvasive positive pressure mechanical ventilation (NIPPV) in exacerbated chronic obstructive pulmonary disease (COPD) has been investigated early and after 1 yr of follow-up. To this end, 30 patients were enrolled in a prospective, controlled trial: 15 had early administration of NIPPV (Group A), 15 had medical therapy only (Group B); assignment was made on the basis of equipment availability only. In-hospital mortality, need for endotracheal intubation and mean length of hospitalization were lower in Group A, though the difference was not statistically significant. Arterial oxygen tension in arterial blood (Pa,O2), carbon dioxide tension in arterial blood (Pa,CO2) and HCO3- improved significantly in both groups from admission to discharge: 45.8+/-8.6 versus 64.9+/-10.0; 59.4+/-11.8 versus 48.6+/-7.3; 34.3+/-4.3 versus 30.1+/-3.4 in group A; 49.2+/-11.4 versus 60.9+/-8.2; 52.6+/-15.9 versus 44.4+/-8.7; 31.7+/-5.9 versus 28.0+/-3.6 in group B, respectively, p<0.05 for all comparisons; pH, percentage forced expiratory volume in one second (FEV1) and tidal volume (VT) improved significantly in patients of group A only: 7.36+/-0.04 versus 7.41+/-0.02; 39.8+/-13.6 versus 49.4+/-11.7; 0.71+/-0.3 versus 0.84+/-0.4, respectively, p<0.05. During follow-up, 3, 6, and 12 months survival rates were significantly higher in Group A than in Group B (p<0.02). Hospital new admissions over 1 yr were more frequent in Group B (n=6, incidence rate: 0.216%) than in Group A (n=4, incidence rate: 0.084%). Therefore, noninvasive positive pressure mechanical ventilation may be added to "conventional" medical therapy in exacerbated chronic obstructive pulmonary disease.