Background: Non-invasive positive pressure ventilation (NPPV) has been widely used to alleviate signs and symptoms of respiratory distress due to cardiogenic pulmonary edema. NPPV prevents alveolar collapse and helps redistribute intra-alveolar fluid, improving pulmonary compliance and reducing the pressure of breathing.
Objectives: To determine the effectiveness and safety of NPPV in the treatment of adult patients with cardiogenic pulmonary edema.
Search strategy: We undertook a comprehensive search of the following databases in April 2005: CENTRAL, MEDLINE, EMBASE, CINAHL, DARE and LILACS. We also reviewed reference lists of included studies and contacted experts, equipment manufacturers, and the Cochrane Heart Group. We did not apply language restrictions.
Selection criteria: We selected blinded or unblinded randomized or quasi-randomized clinical trials, reporting on adult patients with acute or acute-on-chronic cardiogenic pulmonary edema and where NPPV (continuous positive airway pressure (CPAP)) and/or bilevel NPPV plus standard medical care was compared with standard medical care alone.
Data collection and analysis: Two authors independently selected articles and abstracted data using a standardized data collection form. We evaluated study quality with emphasis on allocation concealment, adherence to the intention-to-treat principle and losses to follow-up.
Main results: We included 21 studies involving 1,071 participants. Compared to standard medical care, NPPV significantly reduced hospital mortality (RR 0.6, 95% CI 0.45 to 0.84) and endotracheal intubation (RR 0.53, 95% CI 0.34 to 0.83) with numbers needed to treat of 13 and 8, respectively. We found no difference in hospital length of stay with NPPV, however, intensive care unit stay was reduced by 1 day (WMD -1.07 days, 95% CI -1.60 to -0.53). Compared to standard medical care, we did not observe significant increases in the incidence of acute myocardial infarction with NPPV during (RR 1.24, 95% CI 0.79 to 1.95) or after (RR 0.82, 95% CI 0.09 to 7.54) its application.
Authors' conclusions: NPPV, especially CPAP, in addition to standard medical care is an effective and safe intervention for the treatment of adult patients with acute cardiogenic pulmonary edema.