title: Prone positioning in severe acute respiratory distress syndrome.
abstract: BACKGROUND
  Previous trials involving patients with the acute respiratory distress syndrome (ARDS) have failed to show a beneficial effect of prone positioning during mechanical ventilatory support on outcomes. We evaluated the effect of early application of prone positioning on outcomes in patients with severe ARDS.
  
  
  METHODS
  In this multicenter, prospective, randomized, controlled trial, we randomly assigned 466 patients with severe ARDS to undergo prone-positioning sessions of at least 16 hours or to be left in the supine position. Severe ARDS was defined as a ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen (FiO2) of less than 150 mm Hg, with an FiO2 of at least 0.6, a positive end-expiratory pressure of at least 5 cm of water, and a tidal volume close to 6 ml per kilogram of predicted body weight. The primary outcome was the proportion of patients who died from any cause within 28 days after inclusion.
  
  
  RESULTS
  A total of 237 patients were assigned to the prone group, and 229 patients were assigned to the supine group. The 28-day mortality was 16.0% in the prone group and 32.8% in the supine group (P<0.001). The hazard ratio for death with prone positioning was 0.39 (95% confidence interval [CI], 0.25 to 0.63). Unadjusted 90-day mortality was 23.6% in the prone group versus 41.0% in the supine group (P<0.001), with a hazard ratio of 0.44 (95% CI, 0.29 to 0.67). The incidence of complications did not differ significantly between the groups, except for the incidence of cardiac arrests, which was higher in the supine group.
  
  
  CONCLUSIONS
  In patients with severe ARDS, early application of prolonged prone-positioning sessions significantly decreased 28-day and 90-day mortality. (Funded by the Programme Hospitalier de Recherche Clinique National 2006 and 2010 of the French Ministry of Health; PROSEVA ClinicalTrials.gov number, NCT00527813.).
authors.affiliation: Réanimation Médicale, Hôpital de la Croix-Rousse, Hospices Civils de Lyon; Université de Lyon; and Creatis INSERM 1044, Lyon, France. claude.guerin@chu-lyon.fr
authors.forename: Claude
authors.initials: C
authors.lastname: Guérin
authors.forename: Jean
authors.initials: J
authors.lastname: Reignier
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Richard
authors.forename: Pascal
authors.initials: P
authors.lastname: Beuret
authors.forename: Arnaud
authors.initials: A
authors.lastname: Gacouin
authors.forename: Thierry
authors.initials: T
authors.lastname: Boulain
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Mercier
authors.forename: Michel
authors.initials: M
authors.lastname: Badet
authors.forename: Alain
authors.initials: A
authors.lastname: Mercat
authors.forename: Olivier
authors.initials: O
authors.lastname: Baudin
authors.forename: Marc
authors.initials: M
authors.lastname: Clavel
authors.forename: Delphine
authors.initials: D
authors.lastname: Chatellier
authors.forename: Samir
authors.initials: S
authors.lastname: Jaber
authors.forename: Sylvène
authors.initials: S
authors.lastname: Rosselli
authors.forename: Jordi
authors.initials: J
authors.lastname: Mancebo
authors.forename: Michel
authors.initials: M
authors.lastname: Sirodot
authors.forename: Gilles
authors.initials: G
authors.lastname: Hilbert
authors.forename: Christian
authors.initials: C
authors.lastname: Bengler
authors.forename: Jack
authors.initials: J
authors.lastname: Richecoeur
authors.forename: Marc
authors.initials: M
authors.lastname: Gainnier
authors.forename: Frédérique
authors.initials: F
authors.lastname: Bayle
authors.forename: Gael
authors.initials: G
authors.lastname: Bourdin
authors.forename: Véronique
authors.initials: V
authors.lastname: Leray
authors.forename: Raphaele
authors.initials: R
authors.lastname: Girard
authors.forename: Loredana
authors.initials: L
authors.lastname: Baboi
authors.forename: Louis
authors.initials: L
authors.lastname: Ayzac
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D011175:Positive-Pressure Respiration / Q000379:methods; D016684:Prone Position; D011446:Prospective Studies; D012128:Respiratory Distress Syndrome / Q000401:mortality / Q000628:therapy*
chemical_list: D010100:Oxygen