Assisted and Spontaneous Modes

  • Jean-Michel Arnal


In pressure support mode, flow curve informs about the patient effort and the patient-ventilator synchrony. Observation of flow and pressure curves at the onset of inspiration assesses the patient-ventilator synchrony to trigger the breath and help to optimize inspiratory trigger setting. Observation of the initial increase in flow informs about the setting of pressure rise time. Flow during insufflation informs about the patient’s effort and the adequacy of cycling setting. Observation of pressure and flow at the end of insufflation helps to optimize the expiratory trigger sensitivity. In volume assist control mode, pressure curve informs about the adequacy of inspiratory flow setting.

Supplementary material

Video 4.1

PS (AVI 13838 kb)

Video 4.2

Ineffective effort in PS (AVI 347930 kb)

Video 4.3

Autotriggering in PS (AVI 235030 kb)

Video 4.4

Double trigger in PS (AVI 255763 kb)

Video 4.5

Expiratory trigger sensitivity (AVI 576042 kb)

Video 4.6

Volume assist control (AVI 317975 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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