title: Impact of the prone position in an animal model of unilateral bacterial pneumonia undergoing mechanical ventilation.
abstract: BACKGROUND
  The prone position (PP) has proven beneficial in patients with severe lung injury subjected to mechanical ventilation (MV), especially in those with lobar involvement. We assessed the impact of PP on unilateral pneumonia in rabbits subjected to MV.
  
  
  METHODS
  After endobronchial challenge with Enterobacter aerogenes, adult rabbits were subjected to either "adverse" (peak inspiratory pressure = 30 cm H2O, zero end-expiratory pressure; n = 10) or "protective" (tidal volume = 8 ml/kg, 5 cm H2O positive end-expiratory pressure; n = 10) MV and then randomly kept supine or turned to the PP. Pneumonia was assessed 8 h later. Data are presented as median (interquartile range).
  
  
  RESULTS
  Compared with the supine position, PP was associated with significantly lower bacterial concentrations within the infected lung, even if a "protective" MV was applied (5.93 [0.34] vs. 6.66 [0.86] log10 cfu/g, respectively; P = 0.008). Bacterial concentrations in the spleen were also decreased by the PP if the "adverse" MV was used (3.62 [1.74] vs. 6.55 [3.67] log10 cfu/g, respectively; P = 0.038). In addition, the noninfected lung was less severely injured in the PP group. Finally, lung and systemic inflammation as assessed through interleukin-8 and tumor necrosis factor-α measurement was attenuated by the PP.
  
  
  CONCLUSIONS
  The PP could be protective if the host is subjected to MV and unilateral bacterial pneumonia. It improves lung injury even if it is utilized after lung injury has occurred and nonprotective ventilation has been administered.
authors: Université de Bourgogne, Faculté de Médecine, Dijon, France.
authors: Sylvain
authors: S
authors: Ladoire
authors: Laure-Anne
authors: LA
authors: Pauchard
authors: Saber-Davide
authors: SD
authors: Barbar
authors: Pierre
authors: P
authors: Tissieres
authors: Delphine
authors: D
authors: Croisier-Bertin
authors: Pierre-Emmanuel
authors: PE
authors: Charles
mesh_terms: D000818:Animals; D023381:Endpoint Determination; D021902:Enterobacter aerogenes; D004756:Enterobacteriaceae Infections / Q000382:microbiology / Q000503:physiopathology; D006439:Hemodynamics / Q000502:physiology; D007249:Inflammation / Q000473:pathology; D016209:Interleukin-8 / Q000378:metabolism; D008168:Lung / Q000382:microbiology / Q000473:pathology; D008170:Lung Compliance / Q000502:physiology; D008297:Male; D018410:Pneumonia, Bacterial / Q000382:microbiology / Q000473:pathology / Q000503:physiopathology*; D011175:Positive-Pressure Respiration; D016684:Prone Position / Q000502:physiology*; D011659:Pulmonary Gas Exchange; D011817:Rabbits; D012121:Respiration, Artificial; D016683:Supine Position / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D016209:Interleukin-8; D014409:Tumor Necrosis Factor-alpha