Objective To systematically review the efficacy of noninvasive positive pressure ventilation (NPPV) by helmet in adults with acute respiratory failure. Methods Randomized controlled trials (RCTs) or cohort studies about noninvasive positive pressure ventilation (NPPV) by helmet in adults with acute respiratory failure were retrieved in PubMed, The Cochrane Library (Issue 11, 2016), Web of Science, EMbase, CBM, CNKI and WanFang Data databases from inception to November 2016. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Stata 12.0 software was then used to perform meta-analysis. Results A total of eight studies were included. The results of meta-analysis showed that, NPPV by helmet could significantly reduce the carbon dioxide partial pressure (cohort study: SMD=–0.46, 95%CI –0.75 to –0.18, P=0.001), tracheal intubation rate (RCT: OR=0.36, 95%CI 0.17 to 0.77, P=0.008) and hospital mortality (RCT: OR=0.48, 95%CI 0.24 to 0.98, P=0.044), improve the positive end expiratory pressure (RCT: SMD=1.27, 95%CI 0.87 to 1.67, P<0.05) and respiratory status (RCT: SMD=–0.45, 95%CI –0.81 to –0.08,P=0.017). There was no significant difference in the duration of NPPV(cohort study: OR=–0.20, 95%CI –0.50 to 0.09, P=0.177; RCT: OR=–0.24, 95%CI –0.86 to 0.38, P=0.445). Conclusion NPPV by helmet can reduce the carbon dioxide partial pressure, tracheal intubation rate, hospital mortality and improve the positive end expiratory pressure, respiratory status. But the effects in the duration of NPPV and oxygenation index are uncertain. Due to limited quality and quantity of the included studies, more high quality studies are needed to verify above conclusion.
ObjectiveTo evaluate the effect of prone position ventilation on mortality in ARDS patients by cumulative meta-analysis.MethodsDatabases including PubMed, EMbase, Web of Science, The Cochrane Library, CBM, CNKI, VIP, WanFang Data were searched from inception to September 30th, 2016 to collect randomized controlled trials (RCTs) about prone position ventilation in ARDS patients. Two reviewers independently screened literature, extracted data, and assessed the risk of bias of included studies. In accordance with the published literature or published in chronological order, cumulative meta-analysis was performed using Stata12.0 software, and the trial sequencing analysis (TSA) method was used to assess the reliability and authenticity of the results.ResultsA total of 9 RCTs involving 2 359 patients were included. The cumulative meta-analysis results showed that the prone position ventilation could reduce the mortality in ARDS patients (OR=0.60, 95%CI 0.40 to 0.90). The TSA results showed that the definite conclusion had been obtained before the desired amount of information had been reached.ConclusionThe current evidence shows that prone position ventilation is associated with decreased mortality in ARDS patients. Due to limited quality and quantity of included studies, the above results are needed to validate by more studies.