Abstract: A respiratory assistance device is disclosed. There is a variable speed blower with an output, and a patient ventilation interface configured for fitment on a patient respiratory passageway. A gas passage conduit couples the output of the blower to the patient ventilation interface. A pilot line from the gas passage conduit is coupled to a piloted exhalation valve of the patient ventilation interface. A pressure sensor measures a mask pressure in the patient ventilation interface, and a blower speed sensor measures a speed of the blower. A pressure controller in communication with the pressure sensor and the blower speed sensor detects a patient inspiratory phase and a patient expiratory phase from at least one of the measured speed of the blower and a set speed of the blower. The pressure controller adjusts an operating speed of the blower and actuates the piloted exhalation valve based upon the measured mask pressure.

Abstract: A wake-to-sleep transition for a subject is detected based on responsiveness to breathing cues provided to the subject. A pressurized flow of breathable gas to the airway of subject having one or more gas parameters that are adjusted to provide breathing cues to the subject. Based on a detected conformance of the respiration of the subject to the breathing cues, a determination is made as to whether the subject is awake or asleep.

Abstract: The lung compliance of a subject that is at least partially self-ventilating is determined. The quantification of lung compliance may be an estimation, a measurement, and/or an approximate measurement. The quantification of lung compliance may be enhanced over conventional techniques and/or systems for quantifying lung compliance of self-ventilating subjects in the lung compliance may be quantified relatively accurately without an effort belt or other external sensing device that directly measures diaphragmatic muscle pressure, and without requiring the subject to manually control diaphragmatic muscle pressure. Quantification of lung compliance may be a useful tool in evaluating the health of the subject, including detection of fluid retention associated with developing acute congestive heart failure.

Abstract: The lung compliance of a subject that is at least partially self-ventilating is determined. The quantification of lung compliance may be an estimation, a measurement, and/or an approximate measurement. The quantification of lung compliance may be enhanced over conventional techniques and/or systems for quantifying lung compliance of self-ventilating subjects in the lung compliance may be quantified relatively accurately without an effort belt or other external sensing device that directly measures diaphragmatic muscle pressure, and without requiring the subject to manually control diaphragmatic muscle pressure. Quantification of lung compliance may be a useful tool in evaluating the health of the subject, including detection of fluid retention associated with developing acute congestive heart failure.