Patent ID: 7770578

Claim:
A system for delivering pressurized gas to an airway of a patient comprising: a pressure generating system; a conduit having a first end operatively coupled to the pressure generating system and a second end; a patient interface operatively coupled to the second end of the conduit; a sensor operatively coupled to the pressure generating system, the conduit, or the patient interface, wherein the sensor is adapted to detect a parameter indicative of a patient breathing into the patient interface; and a processor operatively coupled to the sensor and the pressure generating system, wherein the processor determines whether a patient is breathing into the patient interface based on the output of the sensor, wherein the processor is programmed to activate the pressure generating system from a first state in which the pressure generating system does not provide gas to a patient at a treatment pressure to a second state in which the pressure generating system provides a gas to the patient at a first continuous positive airway pressure during inspiratory phases and a third state in which the pressure generating system provides a gas to the patient at a second continuous positive airway pressure during expiratory phases of a respiratory cycle and over multiple successive respiratory cycles, the first continuous pressure different from the second continuous pressure, and wherein the processor causes the pressure generating system to transition from the first state to the second state responsive to a determination that such a patient is breathing into the patient interface.