The present disclosure discloses a method and apparatus for testing vital capacity. The method comprises: measuring a static pressure P.sub.0 of a pressure hole inner cavity of a mobile device; wherein the pressure hole is communicated with the exterior and is purposely disposed on the mobile device or is an already-designed opening; obtaining an air pressure P(t) at each moment by blowing air towards the pressure hole; obtaining an air flow speed v(t) corresponding to each moment according to a correspondence relation formula between the air flow speed v(t) and a pressure differential P(t)−P.sub.0; and obtaining vital capacity Vc of the subject according to a correspondence relationship between a measurement time t and the air flow speed v(t). The technical solution obtains the vital capacity of the subject according to the correspondence relationship between the air flow speed and the measurement time, can effectively improve the vital capacity measurement precision, does not cause damages to related components of the testing apparatus, and is completely different from the solution of using a microphone to measure the vital capacity in the prior art.

Sleep apnea can be treated using positive airway pressure. Methods and systems for determining a level of airway obstruction allow beneficial adjustments to the level of expiratory positive airway pressure used to treat a subject.

Sleep apnea can be treated using positive airway pressure. Methods and systems for determining a level of airway obstruction allow beneficial adjustments to the level of expiratory positive airway pressure used to treat a subject.

A system that determines one or more sleep phenotyping parameters of a subject. In one embodiment, the system comprises a sleep sensor, a stimulus generator, and a processor. The sleep sensor generates signals that convey information related to the physiological functions that indicate the sleep stage of the subject. The stimulus generator provides a stimulus to the subject that enables information related to the sleep phenotyping parameters to be determined. The processor receives the signals generated by the sleep sensor and is in operative communication with the stimulus generator. The processor (i) determines, based on the signals received from the sleep sensor, whether a trigger condition related to the current sleep stage of the subject is satisfied, (ii) controls the stimulus generator to provide the stimulus to the subject if the trigger condition is satisfied, and (iii) quantifies the response of the subject to the stimulus.

Systems and methods for detecting a worsening of patient's heart failure condition based, at least in part, on an increasing trend in a representative rapid shallow breathing index (RSBI) value over multiple days. The RSBI value may be a minimum RSBI, and more particularly may be a minimum RSBI value determined for an afternoon portion of each of the multiple days. The minimum RSBI value measured during an afternoon portion of the day may be more sensitive to changes in a patient's respiration, particularly when a patient is expected to be more active, and thus, may more readily exhibit an increasing trend when patient's heart failure is in decline.

A controller or processor(s) implements detection of respiratory related conditions, such as asynchrony, associated with use of a respiratory treatment apparatus or ventilator. Based on data derived from sensor signals associated with the respiratory treatment, the detector may evaluate a feature set of detection values to determine whether or not an asynchrony occurs in a breath of the patient's respiratory cycle such as by comparing the values against a set of thresholds. Different events may also be identified based on the particular feature set and threshold(s) involved in the detection processing. Automated determination of feature sets may also be implemented to design different asynchrony event classifiers. The methodologies may be implemented by computers or by respiratory treatment apparatus. The detection of such asynchrony events can then also serve as part of control logic for automated adjustments to the control parameters of the respiratory treatment generated by the respiratory treatment apparatus.

A controller or processor(s) implements detection of respiratory related conditions, such as asynchrony, associated with use of a respiratory treatment apparatus or ventilator. Based on data derived from sensor signals associated with the respiratory treatment, the detector may evaluate a feature set of detection values to determine whether or not an asynchrony occurs in a breath of the patient's respiratory cycle such as by comparing the values against a set of thresholds. Different events may also be identified based on the particular feature set and threshold(s) involved in the detection processing. Automated determination of feature sets may also be implemented to design different asynchrony event classifiers. The methodologies may be implemented by computers or by respiratory treatment apparatus. The detection of such asynchrony events can then also serve as part of control logic for automated adjustments to the control parameters of the respiratory treatment generated by the respiratory treatment apparatus.

A single respiratory cycle flow limitation detection method is disclosed. A patient gas delivery signal is received from one or more sensors in pneumatic communication with a ventilation source and a patient ventilation interface to a patient airway. The patient gas delivery signal is representative of a measure of therapeutic gas being delivered to the patient airway at a given time instant, and spans the single patient respiratory cycle. A second derivative of the patient gas delivery signal is generated and a total number of zero crossings therein are counted. These zero crossings are representative of an inflection change in the patient gas delivery signal. A flow limitation indication corresponding to the identified flow limitation is generated when there are at least two zero crossings in the second derivative of the patient gas delivery signal. An angle of deformation representing early, late, or mid-cycle obstruction onsets is generated.

A single respiratory cycle flow limitation detection method is disclosed. A patient gas delivery signal is received from one or more sensors in pneumatic communication with a ventilation source and a patient ventilation interface to a patient airway. The patient gas delivery signal is representative of a measure of therapeutic gas being delivered to the patient airway at a given time instant, and spans the single patient respiratory cycle. A second derivative of the patient gas delivery signal is generated and a total number of zero crossings therein are counted. These zero crossings are representative of an inflection change in the patient gas delivery signal. A flow limitation indication corresponding to the identified flow limitation is generated when there are at least two zero crossings in the second derivative of the patient gas delivery signal. An angle of deformation representing early, late, or mid-cycle obstruction onsets is generated.

A nasal delivery device for and a method of delivering a substance to a nasal cavity of a subject, the delivery device comprising: a delivery unit for delivering a flow entraining a substance to one nostril of a subject, the delivery unit including a nosepiece for fitting to a nostril of the subject; and a flow resistor unit for fitting to the other nostril of the subject, the flow resistor unit including a progressive resistor for progressively providing an increasing flow resistance to the delivered flow.