title: Effects of prone and supine position on oxygenation and inflammatory mediator in a hydrochloric acid-induced lung dysfunction in rats.
abstract: OBJECTIVE
  To compare the effectiveness of mechanical ventilation of supine versus prone position in hydrochloric acid (HCl)-induced lung dysfunction.
  
  
  METHODS
  Twenty, adult, male, Wistar-EPM-1 rats were anesthetized and randomly grouped (n=5 animals per group) as follows: CS-MV (mechanical ventilation in supine position); CP-MV (mechanical ventilation in prone position); bilateral instillation of HCl and mechanical ventilation in supine position (HCl+S); and bilateral instillation of HCl and mechanical ventilation in prone position (HCl+P). All groups were ventilated for 180 minutes. The blood partial pressures of oxygen and carbon dioxide were measured in the time points 0 (zero; 10 minutes before lung injury for stabilization), and at the end of times acid injury, 60, 120 and 180 minutes of mechanical ventilation. At the end of experiment the animals were euthanized, and bronchoalveolar lavages (BALs) were taken to determine the contents of total proteins, inflammatory mediators, and lungs wet-to-dry ratios.
  
  
  RESULTS
  In the HCl+P group the partial pressure of oxygen increased when compared with HCl+S (128.0+/-2.9 mmHg and 111.0+/-6.7 mmHg, respectively) within 60 minutes. TNF-alpha levels in BAL do not differ significantly in the HCl+P group (516.0+/-5.9 pg/mL), and the HCl+S (513.0+/-10.6 pg/mL).
  
  
  CONCLUSIONS
  The use of prone position improved oxygenation, but did not reduce TNF-alpha in BAL upon lung dysfunction induced by HCl.
authors.affiliation: Division of Experimental and Technical, UNIFESP, Sao Paulo, Brazil. souza.oliveira@unifesp.br ijuniors@hotmail.com
authors.forename: Wagner Rogério Souza de
authors.initials: WR
authors.lastname: Oliveira
authors.forename: Ivaldo da
authors.initials: Id
authors.lastname: Silva
authors.forename: Ricardo Santos
authors.initials: RS
authors.lastname: Simões
authors.forename: Luiz Fernando Portugal
authors.initials: LF
authors.lastname: Fuchs
authors.forename: Ricardo Martins
authors.initials: RM
authors.lastname: Oliveira-Filho
authors.forename: Itamar Souza de
authors.initials: IS
authors.lastname: Oliveira-Júnior
mesh_terms: D000818:Animals; D006851:Hydrochloric Acid / Q000494:pharmacology; D008171:Lung Diseases / Q000139:chemically induced / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D010100:Oxygen / Q000097:blood; D016684:Prone Position / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012121:Respiration, Artificial; D016683:Supine Position / Q000502:physiology*; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
chemical_list: D014409:Tumor Necrosis Factor-alpha; D006851:Hydrochloric Acid; D010100:Oxygen