Monitoring During Expiration

  • Jean-Michel Arnal


Expiration is usually passive in patients mechanically ventilated. Expiration monitoring relies mainly on the flow curve which depends on the expiratory time constant. Hence monitoring of expiratory flow informs about the patient’s respiratory mechanics. If the expiratory flow does not reach baseline at the end of expiratory time, dynamic hyperinflation is suspected. An end-expiratory occlusion maneuver is used to measure intrinsic PEEP.

Supplementary material

Video 3.1

Flow limitation (AVI 458531 kb)

Video 3.2

Secretions (AVI 400925 kb)

Video 3.3

End-expiratory occlusion in VC (AVI 175117 kb)

Video 3.4

End-expiratory occlusion in PC (AVI 105999 kb)

Video 3.5

AutoPEEP without dynamic hyperinflation (AVI 324888 kb)

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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  • Jean-Michel Arnal
    • 1
    • 2
  1. 1.Service de Réanimation PolyvalenteHopital Sainte MusseToulonFrance
  2. 2.Applied Research and New TechnologyHamilton Medical AGBonaduzSwitzerland

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