title: Effect of noninvasive positive pressure ventilation on mortality in patients admitted with acute respiratory failure: a meta-analysis.
abstract: OBJECTIVE
  To critically appraise and summarize the trials examining the addition of noninvasive positive pressure ventilation to standard therapy on hospital mortality and need for endotracheal intubation in patients admitted with acute respiratory failure.
  
  
  METHODS
  We searched MEDLINE (1966 to September 1995) and key references were searched forward using the Scientific Citation Index (SCISEARCH). Bibliographies of all selected articles and review articles were examined. Authors of all selected and review articles were contacted by letter to identify unpublished work.
  
  
  METHODS
  a)
  
  
  METHODS
  patients with acute respiratory failure; b) intervention: noninvasive positive pressure ventilation; c) outcome: mortality and/or endotracheal intubation; and d) design: randomized, controlled study. Two of us independently selected the articles for inclusion; disagreements were settled by consensus. Seven (three unpublished) of 212 initially identified studies were selected.
  
  
  METHODS
  Two authors independently extracted data and evaluated methodologic quality of the studies.
  
  
  RESULTS
  Noninvasive positive pressure ventilation was associated with decreased mortality (odds ratio = 0.29; 95% confidence interval 0.15 to 0.59) and a decreased need for endotracheal intubation (odds ratio = 0.20; 95% confidence interval 0.11 to 0.36). Sensitivity analysis suggested a greater benefit of noninvasive positive pressure ventilation in patients with chronic obstructive pulmonary disease (COPD). The inclusion/exclusion of unpublished trials did not influence these results.
  
  
  CONCLUSIONS
  The addition of noninvasive positive pressure ventilation to standard therapy in patients with acute respiratory failure improves survival and decreases the need for endotracheal intubation. However, this effect is restricted to patients whose cause of acute respiratory failure is an exacerbation of COPD. Further research is warranted to determine whether noninvasive positive pressure ventilation confers benefit in patients without COPD who have acute respiratory failure.
authors.affiliation: Division of Critical Care Medicine, University of Western Ontario, London Health Sciences Centre, Canada.
authors.forename: S P
authors.initials: SP
authors.lastname: Keenan
authors.forename: P D
authors.initials: PD
authors.lastname: Kernerman
authors.forename: D J
authors.initials: DJ
authors.lastname: Cook
authors.forename: C M
authors.initials: CM
authors.lastname: Martin
authors.forename: D
authors.initials: D
authors.lastname: McCormack
authors.forename: W J
authors.initials: WJ
authors.lastname: Sibbald
mesh_terms: D000208:Acute Disease; D006801:Humans; D007442:Intubation, Intratracheal; D008173:Lung Diseases, Obstructive / Q000150:complications / Q000628:therapy; D011175:Positive-Pressure Respiration; D016032:Randomized Controlled Trials as Topic; D015203:Reproducibility of Results; D012131:Respiratory Insufficiency / Q000209:etiology / Q000401:mortality* / Q000628:therapy*