title: Effects of frequency and inspiratory plateau pressure during recruitment manoeuvres on lung and distal organs in acute lung injury.
abstract: OBJECTIVE
  To evaluate the effects of frequency and inspiratory plateau pressure (Pplat) during recruitment manoeuvres (RMs) on lung and distal organs in acute lung injury (ALI).
  
  
  METHODS
  We studied paraquat-induced ALI rats. At 24 h, rats were anesthetized and RMs were applied using continuous positive airway pressure (CPAP, 40 cmH(2)O/40 s) or three-different sigh strategies: (a) 180 sighs/h and Pplat = 40 cmH(2)O (S180/40), (b) 10 sighs/h and Pplat = 40 cmH(2)O (S10/40), and (c) 10 sighs/h and Pplat = 20 cmH(2)O (S10/20).
  
  
  RESULTS
  S180/40 yielded alveolar hyperinflation and increased lung and kidney epithelial cell apoptosis as well as type III procollagen (PCIII) mRNA expression. S10/40 resulted in a reduction in epithelial cell apoptosis and PCIII expression. Static elastance and alveolar collapse were higher in S10/20 than S10/40.
  
  
  CONCLUSIONS
  The reduction in sigh frequency led to a protective effect on lung and distal organs, while the combination with reduced Pplat worsened lung mechanics and histology.
authors.affiliation: Laboratory of Pulmonary Investigation, Instituto de Biofísica Carlos Chagas Filho, C.C.S., Universidade Federal do Rio de Janeiro, Ilha do Fundão, Rio de Janeiro, RJ 21941-902, Brazil.
authors.forename: Paula W
authors.initials: PW
authors.lastname: Steimback
authors.forename: Gisele P
authors.initials: GP
authors.lastname: Oliveira
authors.forename: Andréia F
authors.initials: AF
authors.lastname: Rzezinski
authors.forename: Pedro L
authors.initials: PL
authors.lastname: Silva
authors.forename: Cristiane S N B
authors.initials: CS
authors.lastname: Garcia
authors.forename: Graziela
authors.initials: G
authors.lastname: Rangel
authors.forename: Marcelo M
authors.initials: MM
authors.lastname: Morales
authors.forename: José R
authors.initials: JR
authors.lastname: Lapa E Silva
authors.forename: Vera L
authors.initials: VL
authors.lastname: Capelozzi
authors.forename: Paolo
authors.initials: P
authors.lastname: Pelosi
authors.forename: Patricia R M
authors.initials: PR
authors.lastname: Rocco
mesh_terms: D055371:Acute Lung Injury / Q000139:chemically induced*; D000825:Animal Structures / Q000293:injuries*; D000818:Animals; D017209:Apoptosis / Q000502:physiology; D045422:Continuous Positive Airway Pressure / Q000009:adverse effects* / Q000379:methods; D006801:Humans; D017063:Outcome Assessment, Health Care; D011650:Pulmonary Alveoli / Q000473:pathology; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D011999:Recruitment, Neurophysiological / Q000502:physiology*; D015656:Respiratory Mechanics; D055397:Ventilator-Induced Lung Injury