title: Impact of the prolonged slow expiratory maneuver on respiratory mechanics in wheezing infants.
abstract: OBJECTIVE
  To evaluate changes in respiratory mechanics and tidal volume (V T) in wheezing infants in spontaneous ventilation after performing the technique known as the prolonged, slow expiratory (PSE) maneuver.
  
  
  METHODS
  We included infants with a history of recurrent wheezing and who had had no exacerbations in the previous 15 days. For the assessment of the pulmonary function, the infants were sedated and placed in the supine position, and a face mask was used and connected to a pneumotachograph. The variables of tidal breathing (V T and RR) as well as those of respiratory mechanics-respiratory system compliance (Crs), respiratory system resistance (Rrs), and the respiratory system time constant (prs)-were measured before and after three consecutive PSE maneuvers.
  
  
  RESULTS
  We evaluated 18 infants. The mean age was 32 ± 11 weeks. After PSE, there was a significant increase in V T (79.3 ± 15.6 mL vs. 85.7 ± 17.2 mL; p = 0.009) and a significant decrease in RR (40.6 ± 6.9 breaths/min vs. 38.8 ± 0,9 breaths/min; p = 0.042). However, no significant differences were found in the variables of respiratory mechanics (Crs: 11.0 ± 3.1 mL/cmH2O vs. 11.3 ± 2.7 mL/cmH2O; Rrs: 29.9 ± 6.2 cmH2O  mL-1  s-1 vs. 30.8 ± 7.1 cmH2O  mL-1  s-1; and prs: 0.32 ± 0.11 s vs. 0.34 ±0.12 s; p > 0.05 for all).
  
  
  CONCLUSIONS
  This respiratory therapy technique is able to induce significant changes in V T and RR in infants with recurrent wheezing, even in the absence of exacerbations. The fact that the variables related to respiratory mechanics remained unchanged indicates that the technique is safe to apply in this group of patients. Studies involving symptomatic infants are needed in order to quantify the functional effects of the technique.
authors.affiliation: Graduate Program in Rehabilitation Sciences, Universidade Nove de Julho – UNINOVE, Nove de Julho University– São Paulo, Brazil. fclanza@uol.com.br
authors.forename: Fernanda de Cordoba
authors.initials: Fde C
authors.lastname: Lanza
authors.forename: Gustavo Falbo
authors.initials: GF
authors.lastname: Wandalsen
authors.forename: Carolina Lopes da
authors.initials: CL
authors.lastname: Cruz
authors.forename: Dirceu
authors.initials: D
authors.lastname: Solé
mesh_terms: D003430:Cross-Sectional Studies; D005105:Expiratory Reserve Volume / Q000502:physiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D026741:Physical Therapy Modalities / Q000009:adverse effects*; D015656:Respiratory Mechanics / Q000502:physiology*; D012135:Respiratory Sounds / Q000175:diagnosis / Q000502:physiology*; D012138:Respiratory Therapy / Q000379:methods*; D013990:Tidal Volume / Q000502:physiology