title: Expiratory peak flow and respiratory system resistance in mechanically ventilated patients undergoing two different forms of manually assisted cough.
abstract: OBJECTIVE
  Mechanical ventilation is associated with retained airway secretions. Manually assisted cough contributes to the displacement of bronchial mucus, whereas positive end-expiratory pressure increases collateral ventilation and maintains airway patency. This study aimed to assess the effects of manually assisted cough, either alone or added to increased positive end-expiratory pressure and inspiratory time (optimized manually assisted cough), on the expiratory peak flow and respiratory system mechanics in mechanically ventilated patients.
  
  
  METHODS
  In this controlled and randomized clinical trial, respiratory mechanics and expiratory peak flow were assessed in male and female patients undergoing either tracheal suctioning alone, manually assisted cough followed by tracheal suctioning or optimized manually assisted cough followed by tracheal suctioning.
  
  
  RESULTS
  Thirty-five patients completed the trial. Respiratory system resistance was significantly reduced after optimized manually assisted cough (16.0 ± 3.6 versus 12.4 ± 3.1 cmH2O/L/s; p = 0.04). The expiratory peak flow during optimized manually assisted cough was significantly higher in comparison with the values observed during manually assisted cough (112.3 ± 15.6 versus 95.8 ± 18.3 Lpm; p < 0.05). Both values were significantly higher than the values observed in the group undergoing tracheal suctioning alone (52.0 ± 7.6 Lpm; p < 0.001).
  
  
  CONCLUSIONS
  Optimized manually assisted cough increases the expiratory peak flow in comparison with manually assisted cough; in addition, this procedure reduces respiratory system resistance.
authors.forename: Aline Rafaele Barros
authors.initials: AR
authors.lastname: Silva
authors.forename: Sandra Adriano
authors.initials: SA
authors.lastname: Fluhr
authors.forename: Andrezza de Lemos
authors.initials: Ade L
authors.lastname: Bezerra
authors.forename: Marco Aurélio de Valois
authors.initials: MA
authors.lastname: Correia Júnior
authors.forename: Eduardo Ériko Tenório de
authors.initials: EÉ
authors.lastname: França
authors.forename: Flávio Maciel Dias de
authors.initials: FM
authors.lastname: Andrade