Advertisement

Technical Aspects of Patient-Ventilator Interactions

  • R. M. Kacmarek
  • H. Cohen
  • R. L. Goulet
Conference paper

Abstract

It has become increasingly clear that during patient-initiated volume-limited mechanical ventilatory assistance numerous factors can affect patient synchrony with the mechanical ventilator, the two most important being inspiratory trigger sensitivity and peak inspiratory flow. Decreasing inspiratory trigger sensitivity requires a greater system pressure change resulting in greater patient effort to initiate a mechanical breath [1, 2]. This greater effort reflects an increase in ventilatory drive, for there is good correlation between mouth occlusion pressure (P 0.1) and the pressure required to trigger a mechanical breath [3]. In addition, Gurevitch and Gelmont [4] recently noted an increased delay in establishing system pressure during mechanical volume-limited breaths as trigger sensitivity is decreased.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Christopher KL, Neff TA, Bowman JL et al. (1985) Demand and continuous flow intermittent mandatory ventilation systems. Chest 87:625–630PubMedCrossRefGoogle Scholar
  2. 2.
    Marini JJ, Capps JS, Culver BH (1985) The inspiratory work of breathing during assisted mechanical ventilation. Chest 87:612–618PubMedCrossRefGoogle Scholar
  3. 3.
    Fernandez R, Benito S, Sanchis J, Milie-Emili J, Net A (1988) Inspiratory effort and occlusion pressure in triggered mechanical ventilation. Intensive Care Med 14:650–653PubMedGoogle Scholar
  4. 4.
    Gurevitch MJ, Gelmont D (1989) Importance of trigger sensitivity to ventilator response delay in advanced COPD with respiratory failure. Crit Care Med 17:354–359PubMedCrossRefGoogle Scholar
  5. 5.
    Marini JJ, Rodriguez RM, Lamb V (1986) The inspiratory workload of patient-initiated mechanical ventilation. Am Rev Respir Dis 134:902–909PubMedGoogle Scholar
  6. 6.
    Marini JJ, Smith TC, Lamb VJ (1988) External work output and force generation during synchronized intermittent mechanical ventilation. Am Rev Respir Dis 138:1169–1179PubMedGoogle Scholar
  7. 7.
    Gibney RTN, Wilson RS, Pontoppidan H (1982) Comparison of work of breathing on high gas flow and demand valve. Chest 82:692–695PubMedCrossRefGoogle Scholar
  8. 8.
    Viale JP, Annat G, Bertrand O (1985) Additional inspiratory work in intubated patients breathing with continuous positive airway pressure systems. Anesthesiology 63:536–539PubMedCrossRefGoogle Scholar
  9. 9.
    Henry WC, West GA, Wilson RA (1983) A comparison of the oxygen cost of breathing between a continuous-flow CPAP system and a demand-flow CPAP system. Respir Care 28:1273–1281PubMedGoogle Scholar
  10. 10.
    Katz JA, Kraemer RW, Gjerde GE (1985) Inspiratory work and airway pressure with continuous positive pressure delivery systems. Chest 88:519–526PubMedCrossRefGoogle Scholar
  11. 11.
    Hirsch CA, Kacmarek RM, Stanek K (1988) Mechanical ventilator demand-valve function with and without continuous positive airway pressure (CPAP) and pressure support (PS) (abstract). Respir Care 33:908Google Scholar
  12. 12.
    Samodelov LF, Falke KJ (1988) Total inspiratory work with modern demand valve devices compared to continuous flow CPAP. Intensive Care Med 14:632–639PubMedCrossRefGoogle Scholar
  13. 13.
    Bolder PM, Healy TEJ, Bolder AR et al. (1986) The extra work of breathing through adult endotracheal tubes. Anesth Analg 65:853–859PubMedCrossRefGoogle Scholar
  14. 14.
    Shapiro M, Wilson RK, Casar G et al. (1986) Work of breathing through different sized endotracheal tubes. Crit Care Med 14:1028–1031PubMedCrossRefGoogle Scholar
  15. 15.
    Kacmarek RM (1988) The role of pressure support ventilation in reducing work of breathing. Respir Care 33:99–120Google Scholar
  16. 16.
    Braschi A, Sala Gallini G, Rodi G et al. (1989) Relationship between sensitivity of the expiratory trigger and breathing pattern during pressure support ventilation (abstract). Am Rev Respir Dis 139:A361Google Scholar
  17. 17.
    Li-Ing H, MacIntyre NR (1989) Pressure supported breaths: ventilatory effects of breath initiation and breath termination design characteristics. Crit Care Med 17:S26CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1992

Authors and Affiliations

  • R. M. Kacmarek
  • H. Cohen
  • R. L. Goulet

There are no affiliations available

Personalised recommendations