<prompt> All true about pressure control ventilation except-The desired inflation pressure is preselectedThere is accelerating flow rateTidal volume can be variableAlveolar pressure is fixed  <response>: With pressure control ventilation PCV, the desired inflation pressure is preselected, and a decelerating inspiratory flow rate provides high flows at the onset of the lung inflation, to attain the desired inflation pressure quickly. Pressure control modes of ventilation In a pressure controlled mode of ventilation, the inspiratory pressure is the control variable, and is maintained during the inspiratory phase. As a result of this, the pressure waveform is square. This increases the mean airway pressure i.e. the area under the pressuretime graph is greater. During the early inspiratory phase, the ventilator provides a high inspiratory flow rate to rapidly achieve the pressure limit variable PC above PEEP on a SERVO-i. In order to maintain this pressure, the flow rate needs to decrease over the course of inspiration, and it generally takes the shape of a downsloping ramp. During the early inspiratory phase, the ventilator provides a high inspiratory flow rate to rapidly achieve the pressure limit variable . In order to maintain this pressure, the flow rate needs to decrease over the course of inspiration, and it generally takes the shape of a downsloping ramp. 