Patent ID: 6948497

Claim:
A pressure support system comprising: a pressure generating system adapted to generate a flow of breathing gas; a patient circuit having a first end coupled to an outlet of the pressure generating system and a second end; a patient interface device coupled to the second end of the patient circuit; a sensor operatively coupled to the pressure generating system or the patient circuit so as to monitor patient breathing; processing means, operatively coupled to the sensor and the pressure generating system, for (1) causing the pressure generating system to apply the flow of breathing gas to an airway of a patient at an inspiratory positive airway pressure during at least a portion of an inspiratory phase, wherein the inspiratory positive airway pressure is provided at a level relative to an ambient atmospheric pressure that is sufficient to prevent airway obstruction during at least a portion of such a patient's inspiratory breathing cycle, and for (2) adjusting the pressure of the flow of gas in the patient's airway to synchronize the application of positive pressure to such a patient's airway with an occurrence of alternating inspiratory and expiratory phases of such a patient's respiration in a manner to maintain the positive pressure in the patient's airway during a sequence of the inspiratory and expiratory phases, with the magnitude of the positive pressure during at least a portion of each expiratory phase being less than the magnitude of the positive pressure during at least a portion of the immediately preceding inspiratory phase.