A patient ventilator secretion management system is disclosed. The system has a valve with an input in pneumatic communication with a therapeutic breathing gas source. The valve has variable positions, each of which corresponds to a specific flow rate of gas being output therefrom. A patient ventilation interface is in pneumatic communication with the valve over a gas delivery circuit. A controller in communication with the valve regulates the position thereof. The controller sequentially switches the valve from one of the variable positions to another to output a first range of fluctuating flow rates of gas for delivery to the patient ventilation interface during at least a selected one of patient expiratory and inspiratory phases.