Role of noninvasive positive-pressure ventilation in postextubation respiratory failure: a meta-analysis.

BACKGROUND There is a need for an intervention that prevents re-intubation in patients who have been weaned off mechanical ventilation. Noninvasive positive-pressure ventilation (NPPV) has been shown to facilitate weaning in mechanically ventilated patients. OBJECTIVES To assess the effect of NPPV on re-intubation rate and intensive care unit and/or hospital mortality in patients with postextubation respiratory failure. METHODS We searched the MEDLINE, EMBASE, OVID, CINAHL, DARE, and CENTRAL databases for relevant studies published from 1980 to 2006, and included randomized controlled trials that evaluated the role of NPPV in patients with postextubation respiratory failure. Independently and in duplicate, two of us abstracted data from these trials. Differences in opinion were settled via consensus or after consultation with a third author. RESULTS Four studies met our inclusion criteria: two used NPPV in the setting of established postextubation respiratory failure, and two used NPPV in patients "at risk" for postextubation respiratory failure. NPPV, compared to the standard medical therapy, did not decrease the re-intubation rate (relative risk [RR] 1.03, 95% confidence interval [CI]0.84-1.25) or intensive care unit mortality (RR 1.14, 95% CI 0.43-3.0) in patients (n = 302) with postextubation respiratory failure. However, in patients (n = 259) who were defined to be at high risk for developing postextubation respiratory failure, NPPV decreased the re-intubation rate (RR 0.46, 95% CI 0.25-0.84) and intensive care unit mortality (RR 0.26, 95% CI 0.1-0.66), but not the hospital mortality (RR 0.71, 95% CI 0.42-1.20). CONCLUSIONS Current evidence suggests that NPPV should be used judiciously, if at all, in patients with postextubation respiratory failure, but it appears to be promising as a prophylaxis to prevent re-intubation in patients "at risk" for developing postextubation respiratory failure.