Pressure regulated volume control
Pressure regulated volume control (PRVC) is a ventilator mode where the breaths are delivered mandatorily to assure preset volumes, with a constant inspiratory pressure continuously adapting to the patient's condition. The flow pattern is decelerating. This mode is a form of assist control mode of ventilation, the breaths can either be ventilator initiated or patient initiated. This mode combines the advantages of volume controlled and pressure controlled ventilation.
How the ventilator achieves PRVC mode
The first breath delivered to the patient is a volume controlled breath. The measured plateau pressure is used as the pressure level for the next breath. The pressure is constant during the set inspiratory time and the flow is decelerating. The set tidal volume is achieved by automatic, breath-by-breath pressure regulation. The ventilator will adjust the inspiratory pressure control level, according to the mechanical properties of the airways/lung/thorax, to the lowest possible level to guarantee the preset tidal volume. If the measured tidal volume increases above the preset, the pressure level decreases in steps of maximum 3 cmH2O (300 Pa) between consecutive breaths until the preset tidal volume is delivered. Maximum available pressure level is 5 cmH2O (500 Pa) below a preset upper pressure limit.