title: Effects of systematic prone positioning in hypoxemic acute respiratory failure: a randomized controlled trial.
abstract: BACKGROUND
  A recent trial showed that placing patients with acute lung injury in the prone position did not increase survival; however, whether those results hold true for patients with hypoxemic acute respiratory failure (ARF) is unclear.
  
  
  OBJECTIVE
  To determine whether prone positioning improves mortality in ARF patients.
  
  
  METHODS
  Prospective, unblinded, multicenter controlled trial of 791 ARF patients in 21 general intensive care units in France using concealed randomization conducted from December 14, 1998, through December 31, 2002. To be included, patients had to be at least 18 years, hemodynamically stable, receiving mechanical ventilation, and intubated and had to have a partial pressure of arterial oxygen (PaO2) to fraction of inspired oxygen (FIO2) ratio of 300 or less and no contraindications to lying prone.
  
  
  METHODS
  Patients were randomly assigned to prone position placement (n = 413), applied as early as possible for at least 8 hours per day on standard beds, or to supine position placement (n = 378).
  
  
  METHODS
  The primary end point was 28-day mortality; secondary end points were 90-day mortality, duration of mechanical ventilation, incidence of ventilator-associated pneumonia (VAP), and oxygenation.
  
  
  RESULTS
  The 2 groups were comparable at randomization. The 28-day mortality rate was 32.4% for the prone group and 31.5% for the supine group (relative risk [RR], 0.97; 95% confidence interval [CI], 0.79-1.19; P = .77). Ninety-day mortality for the prone group was 43.3% vs 42.2% for the supine group (RR, 0.98; 95% CI, 0.84-1.13; P = .74). The mean (SD) duration of mechanical ventilation was 13.7 (7.8) days for the prone group vs 14.1 (8.6) days for the supine group (P = .93) and the VAP incidence was 1.66 vs 2.14 episodes per 100-patients days of intubation, respectively (P = .045). The PaO2/FIO2 ratio was significantly higher in the prone group during the 28-day follow-up. However, pressure sores, selective intubation, and endotracheal tube obstruction incidences were higher in the prone group.
  
  
  CONCLUSIONS
  This trial demonstrated no beneficial outcomes and some safety concerns associated with prone positioning. For patients with hypoxemic ARF, prone position placement may lower the incidence of VAP.
authors.affiliation: Service de Réanimation Médicale, Hôpital De La Croix-Rousse, Lyon, France. claude.guerin@chu-lyon.fr
authors.forename: Claude
authors.initials: C
authors.lastname: Guerin
authors.forename: Sandrine
authors.initials: S
authors.lastname: Gaillard
authors.forename: Stephane
authors.initials: S
authors.lastname: Lemasson
authors.forename: Louis
authors.initials: L
authors.lastname: Ayzac
authors.forename: Raphaele
authors.initials: R
authors.lastname: Girard
authors.forename: Pascal
authors.initials: P
authors.lastname: Beuret
authors.forename: Bruno
authors.initials: B
authors.lastname: Palmier
authors.forename: Quoc Viet
authors.initials: QV
authors.lastname: Le
authors.forename: Michel
authors.initials: M
authors.lastname: Sirodot
authors.forename: Sylvaine
authors.initials: S
authors.lastname: Rosselli
authors.forename: Vincent
authors.initials: V
authors.lastname: Cadiergue
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Sainty
authors.forename: Philippe
authors.initials: P
authors.lastname: Barbe
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Combourieu
authors.forename: Daniel
authors.initials: D
authors.lastname: Debatty
authors.forename: Jean
authors.initials: J
authors.lastname: Rouffineau
authors.forename: Eric
authors.initials: E
authors.lastname: Ezingeard
authors.forename: Olivier
authors.initials: O
authors.lastname: Millet
authors.forename: Dominique
authors.initials: D
authors.lastname: Guelon
authors.forename: Luc
authors.initials: L
authors.lastname: Rodriguez
authors.forename: Olivier
authors.initials: O
authors.lastname: Martin
authors.forename: Anne
authors.initials: A
authors.lastname: Renault
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Sibille
authors.forename: Michel
authors.initials: M
authors.lastname: Kaidomar
mesh_terms: D000208:Acute Disease; D000368:Aged; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000628:therapy*; D007442:Intubation, Intratracheal; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000209:etiology; D016684:Prone Position; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000009:adverse effects; D012131:Respiratory Insufficiency / Q000150:complications / Q000628:therapy*; D012306:Risk; D016683:Supine Position; D016019:Survival Analysis