title: Mechanisms of the effects of prone positioning in acute respiratory distress syndrome.
abstract: BACKGROUND
  Prone positioning has been used for many years in patients with acute respiratory distress syndrome (ARDS). The initial reason for prone positioning in ARDS patients was improvement in oxygenation. It was later shown that mechanical ventilation in the prone position can be less injurious to the lung and hence the primary reason to use prone positioning is prevention of ventilator-induced lung injury (VILI).
  
  
  METHODS
  A large body of physiologic benefits of prone positioning in ARDS patients accumulated but these failed to translate into clinical benefits. More recently, meta-analyses and randomized controlled trial in a specific subgroup of ARDS patients demonstrated that prone positioning can improve survival. This review covers the effects of prone positioning on oxygenation, respiratory mechanics, and VILI.
  
  
  CONCLUSIONS
  We conclude with the effects of prone positioning on patient outcome, in particular on survival.
authors.affiliation: Service de Réanimation Médicale, Hôpital de la croix-rousse, CHU de Lyon, Bâtiment R, 2ème étage, 103 Grande rue de la croix-rousse, 69004, Lyon, France, claude.guerin@chu-lyon.fr.
authors.forename: C
authors.initials: C
authors.lastname: Guerin
authors.forename: L
authors.initials: L
authors.lastname: Baboi
authors.forename: J C
authors.initials: JC
authors.lastname: Richard
mesh_terms: D003422:Critical Care; D006801:Humans; D016684:Prone Position / Q000502:physiology*; D012128:Respiratory Distress Syndrome / Q000503:physiopathology*