Idealized pressure–time and flow–time graphs for mechanical ventilation. Note that the plateau pressure can be measured when flow returns to zero.
PIP peak inspiratory pressure, Pplat plateau pressure
Trigger and cycle variables for each of the most common types of conventional mechanical ventilation
Idealized pressure–time and flow–time graphs with PEEP set above zero for volume-controlled modes of ventilation
Idealized pressure–time and flow–time graphs with PEEP set above zero for pressure-controlled modes of ventilation
Idealized pressure–time graph for controlled mandatory ventilation (CMV) with PEEP set above zero. In this mode of ventilation, each breath is triggered after a specified time has elapsed. The breaths can be delivered in either volume controlled (shown) or pressure controlled (not shown), depending on the ventilator settings
Idealized pressure–time graph for assist control ventilation (ACV) with PEEP set above zero. In this mode of ventilation, each breath is triggered either due to patient initiation (asterisks) or after a specified time has elapsed (no asterisks). The breaths in ACV can be delivered in either volume controlled (shown) or pressure controlled (not shown), depending on the ventilator settings
Idealized pressure–time graph for intermittent mandatory ventilation (IMV) with PEEP set above zero. In this mode of ventilation, each set breath is triggered after a specified time has elapsed. In addition, the patient can breathe spontaneously between these machine- triggered breaths. The spontaneous breaths create a small relative negative pressure that are depicted in this graph and noted with asterisks. The machine-triggered breaths in IMV can be delivered in either volume controlled (shown) or pressure controlled (not shown), depending on the ventilator settings
Idealized pressure–time graph for synchronized intermittent mandatory ventilation (SIMV) with PEEP set above zero. In this mode of ventilation, each set breath (or mandatory breath) is synchronized to a patient trigger after a specified time has elapsed. In addition, the patient can breathe spontaneously between the mandatory breaths. The spontaneous breaths create a small relative negative pressure that are depicted in this graph and noted with asterisks. The mandatory breaths in SIMV can be delivered in either volume controlled (shown) or pressure controlled (not shown), depending on the ventilator settings
Idealized pressure–time graph for synchronized intermittent mandatory ventilation (SIMV) with PEEP set above zero. In addition, pressure support is being applied to the additional patient-initiated breaths between the mandatory breaths
Idealized pressure–time graph for pressure support ventilation (PSV) with PEEP set above zero. In this mode of ventilation, each breath is triggered by the patient
Reference:
Layon, A. Joseph, Andrea Gabrielli, and William Friedman. Textbook Of Neurointensive Care. London: Springer London, 2013. Print.
Peripheral Brain 