A respiratory assistance apparatus has a gases inlet configured to receive a supply of gases, a blower unit configured to generate a pressurized gases stream from the supply of gases; a humidification unit configured to heat and humidify the pressurized gases stream; and a gases outlet for the heated and humidified gases stream. A flow path for the gases stream extends through the respiratory device from the gases inlet through the blower unit and humidification unit to the gases outlet. A sensor assembly is provided in the flow path before the humidification unit. The sensor assembly has an ultrasound gas composition sensor system for sensing one or more gas concentrations within the gases stream.

The invention relates to a method of determining water level in a humidifier chamber that is part of a humidified gases delivery apparatus and system. The method comprising the steps of delivering power to a heater plate, varying the power delivered to the heater plate, measuring the rate of change of temperature and determining the level of water based on the heating characteristics of the volume of water within the chamber, in particular determining the level of water within the chamber based on the rate of change of temperature and the supplied power.

Systems and method for conducting respiratory therapy in a respiratory system can adjust a flow of respiratory gases to a patient based upon a detected patient breath cycle. The respiratory system can include a non-sealed patient interface. The respiratory system can be configured to deliver a high flow therapy. A patient breath cycle may be determined using one or more measured parameters, such as a flow rate, a blower motor speed, and/or a system pressure. A flow source may be adjusted to have a phase matching that of the patient's breath cycle, such that flow in increased in response to the patient inhaling, and decreased in response to the patient exhaling.

A CPAP machine includes a housing, an air pipe, a blower, and a sensor S. The housing includes a first opening and a second opening. The air pipe is disposed in the housing, and has an inlet port continuous with the first opening, and an outlet port. The sensor S measures a temperature or a humidity of a gas that flows through an internal space of the air pipe. The air pipe includes a box that protrudes outward from a wall of the air pipe and a wall disposed in the box. The wall is disposed in the box to define a space continuous with the internal space of the air pipe, a space, and a space that connects the space and the space to each other. The sensor S is disposed at a wall of the box.

A device (102) provides respiratory treatment for SDB (including mild OSA) and other respiratory conditions. A flow generator warms and humidifies gas at controlled flow levels. For example, the device (102) delivers breathable gas to the upper airway at flow rates of about 10-35 Liters/minute. Levels of flow rate, temperature and/or humidification of the device may be automatically adjusted in response to the detection of SDB events. The device may also automatically deliver adjustments of any of the levels in accordance with detected phases of respiratory cycles. In some embodiments, the device automatically delivers distinct levels to either of the nares based on independent control of flow to each nare. A warm-up procedure controls temperature and humidity at a desired target during a ramp-up of flow to the set therapy level. A cool-down procedure controls temperature above the dewpoint to avoid condensation internal to the device and patient interface.

The gases temperature supplied to a patient when the patient is undergoing treatment such as oxygen therapy or positive pressure treatment for conditions such as Obstructive Sleep Apnea (OSA) or Chronic Obstructive Pulmonary Disease (COPD) is often measured for safety and to enable controlling of the humidity delivered to the patient. The invention disclosed is related to measurement of properties, particularly temperature (thermister 23), of gases flowing through a heated tube (3), supplying gases to a patient, which utilises the heating wire (21, 28) within the tube.

Environmental characteristics or scenes of habitable environments (e.g., hotel or motel rooms, spas, resorts, cruise boat cabins, offices, hospitals and/or homes, apartments or residences, or other spaces or sub-spaces) are controlled to facilitate certain activities of a user in the environment by increasing focus, preparing for sleep, directing movement, masking ambient noise, and improving air quality, among others. Controllable characteristics include, for example, lighting, CO.sub.2/O.sub.2 levels, humidity levels, sound, aroma, and air temperature. Controls are provided for the occupant and/or facility personnel to select activities or scenes, or sensors detect the activity and implement an appropriate scene.

A respiratory humidification system humidifies a flow of respiratory gases supplied to a user. The system can include a main housing that receives a humidification chamber, a heating plate included in the main housing and positioned to contact the humidified chamber and transfer heat to the humidifier chamber, and a heating element that provides heat to the heating plate. The heating element can include a temperature sensor disposed in a central region of the heating element. Disposing the temperature sensor in the central region can reduce a likelihood that conductors of the heating element will cause an incorrect temperature measurement by the temperature sensor.

Sleep apnea can be treated with pressure support therapy using a target pressure level. Detected respiratory events during consecutive multi-session testing period are compared to determine statistical metrics covering gradual changes in therapy efficiency. Adjustments to the target pressure level are based on changes in variability, and maybe made in between therapy sessions.

A reservoir configured to retain a volume of liquid for use in an apparatus for humidifying a flow of pressurized air comprises a base portion and a lid portion. The reservoir may be configured to improve its level of thermal contact to the heater plate using the flow of pressurized air. The reservoir may be configured to improve thermal contact between the reservoir and the heater plate by pre-compression upon engagement of the reservoir with the humidifier. The reservoir may comprise a removable intermediate portion, which may include the inlet tube and/or the outlet tube, for improved access for cleaning. The reservoir may also be configured to prevent overfilling. Overfill prevention features in the reservoir may include defined flow egress paths and/or formation of air locks.