Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2011;15(1):R6.
doi: 10.1186/cc9403. Epub 2011 Jan 6.

An updated study-level meta-analysis of randomised controlled trials on proning in ARDS and acute lung injury

Fekri Abroug  1 , Lamia Ouanes-Besbes, Fahmi Dachraoui, Islem Ouanes, Laurent Brochard
Affiliations
Meta-Analysis

An updated study-level meta-analysis of randomised controlled trials on proning in ARDS and acute lung injury

Fekri Abroug et al. Crit Care. 2011.

Abstract

Introduction: In patients with acute lung injury (ALI) and/or acute respiratory distress syndrome (ARDS), recent randomised controlled trials (RCTs) showed a consistent trend of mortality reduction with prone ventilation. We updated a meta-analysis on this topic.

Methods: RCTs that compared ventilation of adult patients with ALI/ARDS in prone versus supine position were included in this study-level meta-analysis. Analysis was made by a random-effects model. The effect size on intensive care unit (ICU) mortality was computed in the overall included studies and in two subgroups of studies: those that included all ALI or hypoxemic patients, and those that restricted inclusion to only ARDS patients. A relationship between studies' effect size and daily prone duration was sought with meta-regression. We also computed the effects of prone positioning on major adverse airway complications.

Results: Seven RCTs (including 1,675 adult patients, of whom 862 were ventilated in the prone position) were included. The four most recent trials included only ARDS patients, and also applied the longest proning durations and used lung-protective ventilation. The effects of prone positioning differed according to the type of study. Overall, prone ventilation did not reduce ICU mortality (odds ratio = 0.91, 95% confidence interval = 0.75 to 1.2; P = 0.39), but it significantly reduced the ICU mortality in the four recent studies that enrolled only patients with ARDS (odds ratio = 0.71; 95% confidence interval = 0.5 to 0.99; P = 0.048; number needed to treat = 11). Meta-regression on all studies disclosed only a trend to explain effect variation by prone duration (P = 0.06). Prone positioning was not associated with a statistical increase in major airway complications.

Conclusions: Long duration of ventilation in prone position significantly reduces ICU mortality when only ARDS patients are considered.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Flow diagram of the meta-analysis.
Figure 2
Figure 2
Cumulative meta-analysis of prone ventilation on intensive care unit mortality. The first row shows the effect based on one study, the second row shows the cumulative effects based on two studies, and so on. CI, confidence interval.
Figure 3
Figure 3
Effects of prone ventilation on intensive care unit mortality. Point estimates (by random-effects model) are reported separately for the groups of studies that included both acute lung injury (ALI) and acute respiratory distress syndrome patients (ARDS), those that included only ARDS patients, and the pooled overall effects of all meta-analysis-included patients. CI, confidence interval.
Figure 4
Figure 4
Meta-regression analysis of effects of prone duration (actually applied in included studies) on mortality. Log odds ratio plotted according to prone duration with the summary fixed-effects meta-regression (z = -1.88; P = 0.06). Each study is represented by a circle proportional to its weight in the meta-analysis reflecting the greatest impact on the slope of the regression line.
Figure 5
Figure 5
Incidence of major airway complications. CI, confidence interval.
See this image and copyright information in PMC

References

    1. Gattinoni L, Tognoni G, Pesenti A, Taccone P, Mascheroni D, Labarta V, Malacrida R, Di Giulio P, Fumagalli R, Pelosi P, Brazzi L, Latini R. Effect of prone positioning on the survival of patients with acute respiratory failure. N Engl J Med. 2001;345:568–573. doi: 10.1056/NEJMoa010043. - DOI - PubMed
    1. Guerin C, Gaillard S, Lemasson S, Ayzac L, Girard R, Beuret P, Palmier B, Le QV, Sirodot M, Rosselli S, Cadiergue V, Sainty JM, Barbe P, Combourieu E, Debatty D, Rouffineau J, Ezingeard E, Millet O, Guelon D, Rodriguez L, Martin O, Renault A, Sibille JP, Kaidomar M. Effects of systematic prone positioning in hypoxemic acute respiratory failure: a randomized controlled trial. JAMA. 2004;292:2379–2387. doi: 10.1001/jama.292.19.2379. - DOI - PubMed
    1. Voggenreiter G, Aufmkolk M, Stiletto RJ, Baacke MG, Waydhas C, Ose C, Bock E, Gotzen L, Obertacke U, Nast-Kolb D. Prone positioning improves oxygenation in post-traumatic lung injury - a prospective randomized trial. J Trauma. 2005;59:333–341. doi: 10.1097/01.ta.0000179952.95921.49. discussion 341-343. - DOI - PubMed
    1. Curley MA, Hibberd PL, Fineman LD, Wypij D, Shih MC, Thompson JE, Grant MJ, Barr FE, Cvijanovich NZ, Sorce L, Luckett PM, Matthay MA, Arnold JH. Effect of prone positioning on clinical outcomes in children with acute lung injury: a randomized controlled trial. JAMA. 2005;294:229–237. doi: 10.1001/jama.294.2.229. - DOI - PMC - PubMed
    1. Abroug F, Ouanes-Besbes L, Elatrous S, Brochard L. The effect of prone positioning in acute respiratory distress syndrome or acute lung injury: a meta-analysis. Areas of uncertainty and recommendations for research. Intensive Care Med. 2008;34:1002–1011. doi: 10.1007/s00134-008-1062-3. - DOI - PubMed

LinkOut - more resources