Which patients with acute exacerbation of chronic obstructive pulmonary disease benefit from noninvasive positive-pressure ventilation? A systematic review of the literature

Background: Over the past decade, noninvasive positive-pressure ventilation (NPPV) in the setting of acute exacerbations of chronic obstructive pulmonary disease (COPD) has increased in popularity. Although several trials have been published on the relative effectiveness of this treatment, apparent inconsistencies in study results remain. Purpose: To assess the effect of NPPV on rate of endotracheal intubation, length of hospital stay, and in-hospital mortality rate in patients with an acute exacerbation of COPD and to determine the effect of exacerbation severity on these outcomes. Data Sources: MEDLINE (1966 to 2002) and EMBASE (1990 to 2002). Additional data sources included the Cochrane Library, personal files, abstract proceedings, reference lists of selected articles, and expert contact. There were no language restrictions. Study Selection: The researchers selected randomized, controlled trials that 1) examined patients with acute exacerbation of COPD; 2) compared noninvasive ventilation and standard therapy with standard therapy alone; and 3) included need for endotracheal intubation, length of hospital stay, or hospital survival as an outcome. Data Extraction: Methodologic quality and results were abstracted independently and in duplicate. Data Synthesis: The addition of NPPV to standard care in patients with an acute exacerbation of COPD decreased the rate of endotracheal intubation (risk reduction, 28% [95% CI, 15% to 40%]), length of hospital stay (absolute reduction, 4.57 days [CI, 2.30 to 6.83 days]), and in-hospital mortality rate (risk reduction, 10% [CI, 5% to 15%]). However, subgroup analysis showed that these beneficial effects occurred only in patients with severe exacerbations, not in those with milder exacerbations. Conclusions: Patients with severe exacerbations of COPD benefit from the addition of NPPV to standard therapy. However, NPPV has not been shown to benefit hospitalized patients with milder COPD exacerbations.