A breathing system configured to deliver high-flow or bubble CPAP therapy

Abstract

A breathing system including a flow generator can provide bubble CPAP therapy by controlling the pressure of the gas flow delivered to a patient. A controller of the breathing system can control the motor speed of the flow generator to control the pressure of the gas flow. The controller can also detect the presence of bubbles and / or potential leaks in the gas path of the system. The breathing system can include a high-flow breathing system.

Description

[Technical Field]

[0001] The present disclosure relates to methods and systems for delivering respiratory flow therapy to a patient. In particular, the present disclosure relates to using a flow generator to deliver bubble CPAP therapy. [Background technology]

[0002] Respiratory support devices are used to deliver a flow of gas to a user or patient in a variety of settings, such as hospitals, medical facilities, home care, or domestic environments. Respiratory support or respiratory therapy devices (collectively, "respiratory devices" or "respiratory equipment") may be used to deliver supplemental oxygen or other gases along with the gas flow, and / or humidification devices may be used to deliver heated and humidified gas. Respiratory devices may allow for the regulation and control of characteristics of the gas flow, including flow rate, temperature, gas concentration, humidity, pressure, etc. Sensors, such as flow and / or pressure sensors, are used to measure the characteristics of the gas flow. Summary of the Invention [Means for solving the problem]

[0003] Bubble continuous positive airway pressure (CPAP) is a form of respiratory therapy in which a patient (typically an infant) is provided with a flow of gas through a patient interface. The flow of gas is typically provided by a gas source located in the wall of a hospital or clinic, or may be provided by a cylinder of compressed air and / or oxygen, for example, during transport. The patient interface is connected to two conduits: an inhalation conduit and an exhalation conduit. The inhalation conduit provides gas to the patient. The exhalation conduit provides a path for exhaled gas from the patient. The exhalation conduit communicates with a pressure regulator, which is used to set the pressure. The pressure regulator may be a chamber with a column of water in which the end portion of the exhalation conduit is submerged. Exhaled gas is released into the pressure regulator. The exhaled gas being released into the water bubbles into the water, creating a bubbling effect. The patient interface is typically configured to form a seal with the patient's mouth and / or nose. Examples of tight-fitting patient interfaces may include a nasal mask, an oral mask, a full face mask, nasal pillows, or a cannula with tight-fitting nasal prongs.

[0004] In some locations, for example, in some developing countries or remote areas, a wall source may not be available. The present disclosure provides systems and methods for providing bubble CPAP therapy that include a flow generator instead of and / or optionally in addition to a wall source. The flow generator may also include an integrated humidifier for heating and humidifying the gas flow. An example of a flow generator with an integrated humidifier is a high-flow breathing apparatus. A heated breathing tube may also be used with a high-flow breathing apparatus to deliver the gas flow from the humidifier to the patient interface. The flow generator may also include an integrated blender to provide supplemental gases to the gas flow. The flow generator is preferably one that draws in ambient gas, e.g., ambient air, rather than being connected to a gas source, e.g., a gas tank or wall source. The blender allows one or more supplemental gases to be mixed with the drawn-in ambient gas.

[0005] High-flow breathing devices can provide a variety of modes of therapy, such as, but not limited to, high-flow therapy (also known as nasal high-flow therapy or tracheal high-flow therapy), CPAP, bi-level, and bubble CPAP, eliminating the need for patients to switch to different breathing devices when switching between different modes of respiratory therapy (e.g., when the patient's condition changes).

[0006] The high-flow respiratory device can operate in a bubble CPAP therapy mode or a nasal high-flow therapy mode (as described in more detail below). Additionally or alternatively, the high-flow respiratory device can also operate in other high-flow therapy modes, such as tracheal high flow or other high flows. Nasal high flow is delivered through a nasal interface. Tracheal high flow can be delivered by a tracheal interface. Other interfaces, such as an oral interface, may also be possible to provide high flow to the airways via an oral passageway. The described respiratory device can operate in a high-flow therapy mode or a bubble CPAP mode.

[0007] The high-flow breathing apparatus may operate as a flow-controlled device (e.g., the high-flow breathing apparatus may control a blower motor to achieve a target flow), as described in more detail below. The target flow may be a constant flow rate. The target flow may be set by the user or may be based on the device being in a bubble CPAP therapy mode or a nasal high-flow therapy mode. In one example, the controller may include predefined target flow rates for the bubble CPAP therapy mode and the nasal high-flow therapy mode. The predefined target flow rates may be stored in the memory of the controller.

[0008] When operating in bubble CPAP mode, a high-flow respiratory device may control the motor speed of its flow generator, which may be a blower, to deliver a constant flow rate (including a substantially constant flow rate). The respiratory device may monitor the pressure in the breathing circuit (also called the breathing tube or inspiratory conduit) or in the respiratory device's flow path and adjust the target motor speed if the pressure exceeds this limit. The respiratory device may also replace the pressure relief valve in traditional bubble CPAP systems with software control to provide better pressure control over the gas flow. The respiratory device may provide multiple alarms and monitors. For example, the respiratory device may determine whether there is an irregular amount of leakage, an obstruction, intermittent bubbling, suggested and / or automatic flow rate changes, a flow rate that does not meet the required inspiratory volume when the pressure exceeds a threshold, and / or detect whether bubbling is present. The high-flow respiratory device may also further limit the generated pressure to ensure that the pressure delivered to the patient is below a pressure limit. In one example, in bubble CPAP mode, the flow rate may be high.

[0009] The terms breathing apparatus and breathing equipment may be used interchangeably to describe and define the same item.

[0010] The breathing apparatus or breathing device may be part of a breathing system that includes one or more additional components (eg, an inhalation tube, an exhalation tube, a bubbler), as described in more detail below.

[0011] In some forms, a respiratory device configured to deliver respiratory therapy to a patient via a patient interface may include a controller; a blower including a motor, wherein a motor speed of the blower may be controlled by the controller; a pressure sensor configured to measure a pressure of a gas flow downstream of the blower; the controller may be configured to: compare the pressure to a threshold; reduce a target motor speed of the blower in response to the pressure exceeding the threshold; and control the motor speed to achieve a target flow rate in response to the pressure being equal to or less than the threshold.

[0012] In some forms, a respiratory device configured to deliver respiratory therapy to a patient via a patient interface, the device may include: a controller; a blower including a motor, the blower motor speed being controlled by the controller to a target motor speed; the blower may include a pressure sensor configured to measure a pressure of a gas flow downstream of the blower; the controller configured to: compare the pressure to a threshold; reduce a target motor speed of the blower in response to the pressure being above the threshold; and adjust the target motor speed to achieve a target flow rate in response to the pressure being equal to or less than the threshold.

[0013] In some forms, a respiratory device configured to deliver respiratory therapy to a patient via a patient interface, the device may include: a controller; a blower controlled by the controller; a pressure sensor configured to measure the pressure of a gas flow downstream of the blower; the controller configured to: compare the pressure to a threshold; if the pressure is above the pressure threshold, control the blower to reduce the pressure below the threshold; and if the pressure is at or below the threshold, control the blower to achieve a target flow rate.

[0014] In some embodiments, the blower includes a motor.

[0015] In some embodiments, the blower is controlled by controlling one or more of: a motor speed, a motor current, and / or a motor voltage to a target motor speed, a target motor current, and / or a target motor voltage.

[0016] In some embodiments, the target motor speed may be reduced at a constant rate. In some embodiments, the target motor speed may be reduced at a variable rate.

[0017] In some forms, the controller may be configured to continuously reduce the target motor speed until the pressure falls below a threshold value.

[0018] In some forms, the pressure sensor may be an absolute pressure sensor.

[0019] In some forms, the pressure may be measured by taking the difference between the reading of the pressure sensor and the reading of a second pressure sensor, both of which are absolute pressure sensors.

[0020] In some forms, the pressure sensor may be a gauge pressure sensor configured to take the difference between ambient pressure and the pressure downstream of the blower.

[0021] In some forms, the controller can be configured to receive an input of a target flow rate.

[0022] In some forms, the target flow rate can be set by the user.

[0023] In some forms, the device may include an oxygen inlet that is separate from the ambient air inlet.

[0024] In some forms, the blower may be configured to mix ambient air from the ambient air inlet with oxygen from the oxygen inlet.

[0025] In some forms, FdO2 may depend in part on the target flow rate.

[0026] In some forms, the controller may be further configured to control FdO2 by controlling the opening of the oxygen inlet valve.

[0027] In some embodiments, the target flow rate may be constant.

[0028] In some forms, the device may be coupled to a bubbler, and the controller may be configured to detect bubbling by monitoring changes in the flow parameter signal.

[0029] In some forms, the flow parameter signal may include a flow signal, a pressure signal, or a combination thereof.

[0030] In some forms, the change may be a change in amplitude of the flow parameter signal from a threshold value.

[0031] In some embodiments, the changes may be analyzed in the frequency domain.

[0032] In some forms, the controller may be configured to output a warning in response to a lack of foaming for a predetermined period of time.

[0033] In some forms, the controller may be configured to output one or more of the following warnings based on whether foaming is detected: leak, blockage, intermittent foaming, suggested and / or automatic flow rate changes, and / or a flow rate that does not meet the required inspiratory volume.

[0034] In some forms, the device may further include a humidification chamber.

[0035] In some embodiments, the device may further include one or more flow sensors.

[0036] In some forms, the device may be a high-flow breathing device.

[0037] In some embodiments, the system includes a battery.

[0038] In some configurations, the battery is the primary power source for the device.

[0039] In some embodiments, the battery is an auxiliary power source for the device.

[0040] In some embodiments, the device includes a motor speed limit.

[0041] In some embodiments, the motor speed limit is based on the ambient pressure or an ambient pressure.

[0042] In some forms, the system may include any combination of the devices described above. The system may further include an inspiratory conduit for providing gas flow to the patient interface.

[0043] In some forms, the patient interface may form a seal on or around the patient's face.

[0044] In some forms, the patient interface may be configured to connect to an exhalation conduit.

[0045] In some forms, the exhalation conduit may be configured to connect to a bubbler.

[0046] In some forms, the system may not include a pressure relief valve between the blower and the patient interface.

[0047] In some forms, a method of providing bubble CPAP via a patient interface coupled to a respiratory device including a flow generator, the flow generator including a motor in electrical communication with a controller of the respiratory device, the method may include measuring a pressure of a gas flow downstream of the flow generator based on readings from a pressure sensor; comparing the pressure to a threshold; reducing a target motor speed of the flow generator in response to the pressure being above the threshold; and controlling the motor speed to achieve a target flow rate in response to the pressure being equal to or less than the threshold.

[0048] In some forms, a method of providing bubble CPAP via a patient interface coupled to a respiratory device including a flow generator, the flow generator including a motor in electrical communication with a controller of the respiratory device, the controller configured to control the motor to a target motor speed, the method may include measuring a pressure of a gas flow downstream of the flow generator based on a reading from a pressure sensor; comparing the pressure to a threshold; reducing the target motor speed of the flow generator in response to the pressure being above the threshold; and adjusting the target motor speed to achieve the target flow rate in response to the pressure being equal to or less than the threshold.

[0049] In some forms, a method of providing bubble CPAP via a patient interface coupled to a respiratory device including a flow generator, the flow generator including a blower, and optionally the blower including a motor in electrical communication with a controller of the respiratory device, the controller configured to control the motor to a target motor speed, the method may include measuring a pressure of a gas flow downstream of the flow generator based on a reading from a pressure sensor; comparing the pressure to a threshold; if the pressure is above the pressure threshold, controlling the blower to reduce the pressure below the threshold; and if the pressure is equal to or less than the threshold, controlling the blower to achieve the target flow rate.

[0050] In some embodiments, the blower is controlled by controlling one or more of: a motor speed, a motor current, and / or a motor voltage to a target motor speed, a target motor current, and / or a target motor voltage.

[0051] In some embodiments, the target motor speed may be reduced at a constant rate. In some embodiments, the target motor speed may be reduced at a variable rate.

[0052] In some forms, the method may include continually decreasing the target motor speed until the pressure falls below a threshold value.

[0053] In some forms, the pressure sensor may be an absolute pressure sensor.

[0054] In some forms, the measurement may include taking the difference between a reading of the pressure sensor and a reading of a second pressure sensor, both of which are absolute pressure sensors.

[0055] In some forms, the pressure sensor may be a gauge pressure sensor configured to take the difference between ambient pressure and the pressure downstream of the flow generator.

[0056] In some embodiments, the target flow rate may be constant.

[0057] In some forms, the method can include receiving an input of a target flow rate.

[0058] In some forms, the target flow rate can be set by the user.

[0059] In some forms, the control may include implementing a PID controller to determine the desired motor speed based on the difference between the target flow rate and the flow rate delivered to the patient as measured by one or more flow sensors.

[0060] In some forms, the device may include an oxygen inlet that is separate from the ambient inlet.

[0061] In some forms, the flow generator may be configured to mix ambient air from the ambient air inlet with oxygen from the oxygen inlet.

[0062] In some forms, FdO2 may depend in part on the target flow rate.

[0063] In some forms, the method may further include controlling the FdO2 by controlling the opening of an oxygen inlet valve.

[0064] In some forms, the method may further include detecting bubbling in a bubbler coupled to the respiratory device by monitoring a change in the flow parameter signal.

[0065] In some forms, the flow parameter signal may include a flow signal, a pressure signal, or a combination thereof.

[0066] In some forms, the change may be a change in amplitude of the flow parameter signal from a threshold value.

[0067] In some embodiments, the changes may be analyzed in the frequency domain.

[0068] In some forms, the method may further include outputting a warning in response to a lack of foaming for a predetermined period of time.

[0069] In some forms, the method may further include outputting one or more of the following warnings based on whether foaming is detected: leak, blockage, intermittent foaming, suggested and / or automatic flow rate changes, and / or a flow rate that does not meet the required inspiratory volume.

[0070] In some forms, the device may further include a humidification chamber.

[0071] In some embodiments, the device includes a battery.

[0072] In some configurations, the battery is the primary power source for the device.

[0073] In some embodiments, the battery is an auxiliary power source for the device.

[0074] In some embodiments, the device includes a motor speed limit.

[0075] In some embodiments, the motor speed limit is based on the ambient pressure or an ambient pressure.

[0076] In some forms, the device may be included in a breathing system that includes a patient interface, and the system does not include a pressure relief valve between the flow generator and the patient interface.

[0077] In some forms, a respiratory device may be coupled to the inhalation conduit to provide a flow of gas to the patient interface.

[0078] In some forms, the patient interface may form a seal on or around the patient's face.

[0079] In some forms, the patient interface may be configured to connect to an exhalation conduit.

[0080] In some forms, the exhalation conduit may be configured to connect to a bubbler.

[0081] In some forms, a respiratory system configured to deliver bubble CPAP therapy to a patient via a patient interface may include a respiratory device including: a controller, a blower including a motor, the blower motor speed of which may be controlled by the controller, the blower configured to generate a flow of gas to the patient at a target flow rate, and a housing enclosing the controller and the blower; an inspiratory conduit for providing the gas flow to the patient interface; and an expiratory conduit having a proximal end and a distal end, the proximal end coupled to the patient interface and the distal end submerged at a predetermined depth in the water column.

[0082] In some forms, the system may further include a pressure sensor configured to measure the pressure of the gas flow downstream of the blower, and the controller may be configured to: compare the pressure to a threshold; reduce a target motor speed of the blower in response to the pressure exceeding the threshold; and control the motor speed to achieve the target flow rate in response to the pressure being equal to or less than the threshold.

[0083] In some forms, a respiratory system configured to deliver bubble CPAP therapy to a patient via a patient interface may include a respiratory device including: a controller; a blower including a motor, wherein the blower motor speed may be controlled by the controller to a target motor speed, the blower configured to generate a flow of gas to the patient at a target flow rate, and a housing enclosing the controller and the blower; an inspiratory conduit for providing the gas flow to the patient interface; and an expiratory conduit having a proximal end and a distal end, the proximal end coupled to the patient interface and the distal end submerged at a predetermined depth in the water column.

[0084] The blower includes an inlet that draws in ambient air and forces it toward the patient via the patient conduit (i.e., inhalation conduit). A controller controls the blower to a target motor speed or a target flow rate, or both. The controller preferably provides a control signal to control, i.e., vary, the current, voltage, or power provided to the blower motor to achieve the target motor speed or target flow rate. The breathing system may also optionally include a supplemental gas inlet for receiving a supplemental gas, such as oxygen. The blower is configured to receive and mix the ambient gas and the supplemental gas.

[0085] In some forms, the system may further include a pressure sensor configured to measure the pressure of the gas flow downstream of the blower, and the controller may be configured to: compare the pressure to a threshold; reduce a target motor speed of the blower in response to the pressure exceeding the threshold; and adjust the target motor speed to achieve the target flow rate in response to the pressure being equal to or less than the threshold.

[0086] In some forms, the system may further include a pressure sensor configured to measure the pressure of the gas flow downstream of the blower, and the controller may be configured to: compare the pressure to a threshold; if the pressure is above the pressure threshold, control the blower to reduce the pressure below the threshold; and if the pressure is below the threshold, control the blower to achieve the target flow rate.

[0087] In some embodiments, the blower is controlled by controlling one or more of: a motor speed, a motor current, and / or a motor voltage to a target motor speed, a target motor current, and / or a target motor voltage.

[0088] In some embodiments, the target motor speed may be reduced at a constant rate. In some embodiments, the target motor speed may be reduced at a variable rate.

[0089] In some forms, the controller may be configured to continuously reduce the target motor speed until the pressure falls below a threshold value.

[0090] In some forms, the pressure sensor may be an absolute pressure sensor.

[0091] In some forms, the pressure may be measured by taking the difference between the reading of the pressure sensor and the reading of a second pressure sensor, both of which are absolute pressure sensors.

[0092] In some forms, the pressure sensor may be a gauge pressure sensor configured to take the difference between ambient pressure and the pressure downstream of the blower.

[0093] In some embodiments, the target flow rate may be constant.

[0094] In some forms, the controller can be configured to receive an input of a target flow rate.

[0095] In some forms, the target flow rate can be set by the user.

[0096] In some forms, the device may include an oxygen inlet that is separate from the ambient inlet.

[0097] In some forms, the blower may be configured to mix ambient air from the ambient air inlet with oxygen from the oxygen inlet.

[0098] In some forms, FdO2 may depend in part on the target flow rate.

[0099] In some forms, the controller may be further configured to control FdO2 by controlling the opening of the oxygen inlet valve.

[0100] In some embodiments, the system may include a bubbler, which contains the water column.

[0101] In some forms, the controller may be configured to detect foaming by monitoring changes in the flow parameter signal.

[0102] In some forms, the flow parameter signal may include a flow signal, a pressure signal, or a combination thereof.

[0103] In some forms, the change may be a change in amplitude of the flow parameter signal from a threshold value.

[0104] In some embodiments, the changes may be analyzed in the frequency domain.

[0105] In some forms, the controller may be configured to output a warning in response to a lack of foaming for a predetermined period of time.

[0106] In some forms, the controller may be configured to output one or more of the following warnings based on whether foaming is detected: leak, blockage, intermittent foaming, suggested and / or automatic flow rate changes, and / or a flow rate that does not meet the required inspiratory volume.

[0107] In some forms, the patient interface may form a seal on or around the patient's face.

[0108] In some forms, the device may further include a humidification chamber.

[0109] In some embodiments, the device may further include one or more flow sensors.

[0110] In some forms, the system may not include a pressure relief valve between the blower and the patient interface.

[0111] In some forms, the device may be a high-flow breathing device.

[0112] In some embodiments, the device includes a battery.

[0113] In some configurations, the battery is the primary power source for the device.

[0114] In some embodiments, the battery is an auxiliary power source for the device.

[0115] In some embodiments, the device includes a motor speed limit.

[0116] In some embodiments, the motor speed limit is based on the ambient pressure or an ambient pressure.

[0117] In some embodiments, a breathing system configured to deliver high-flow therapy or bubble CPAP therapy includes: a breathing device including a flow generator; a humidifier in fluid communication with the flow generator; a controller that electronically controls the flow generator; and an inhalation conduit in fluid communication with the humidifier, wherein the breathing device is switchable between a high-flow therapy mode and a bubble CPAP therapy mode, wherein in the high-flow therapy mode, the breathing device is configured to deliver high-flow therapy, and in the bubble CPAP therapy mode, the breathing device is configured to deliver bubble CPAP therapy.

[0118] In some forms, the high flow therapy is nasal high flow therapy.

[0119] In some forms, the respiratory device includes a housing, and the flow generator and humidifier are incorporated into the housing. A controller is also positioned within the housing. The humidifier may include a heating plate and a humidification chamber. The heating plate is positioned within the housing. The housing defines a chamber space, and the heating plate is within the chamber space. The humidification chamber is removably positioned on the heating plate. The housing includes a gas outlet, and the inhalation conduit is connectable to the outlet.

[0120] In the high flow therapy mode, the system includes a loose-fitting patient interface coupled to the inhalation conduit.

[0121] In the high flow therapy mode, the system includes a loose-fitting patient interface coupled to the inhalation conduit.

[0122] In some forms, the loose patient interface may be a nasal cannula.

[0123] In some forms, during use, the nasal cannula is positioned on the user's face to deliver gas to the user's nostrils.

[0124] In a bubble CPAP therapy mode, the system includes a tight fitting patient interface coupled to an inspiratory conduit, an expiratory conduit coupled to the tight fitting patient interface, and the expiratory conduit coupled to a pressure regulator to regulate pressure within the patient interface and / or the patient's airway.

[0125] In some embodiments, the pressure regulator includes a chamber with a water column and the expiratory conduit is submerged in the water column, the pressure delivered to the user being defined or set by the depth to which the expiratory conduit is submerged in the water column.

[0126] In some embodiments, the inhalation conduit is common to both the high-flow therapy mode and the bubble CPAP therapy mode.

[0127] In some forms, the controller includes a high flow therapy control program associated with a high flow therapy mode.

[0128] In some forms, the controller includes a bubble CPAP therapy control program associated with a bubble CPAP therapy mode.

[0129] In some embodiments, the controller is configured to select and activate a program corresponding to the selected mode of operation.

[0130] In some embodiments, each program defines operating parameters.

[0131] In some forms, the operating parameters may include one or more of a motor speed or a pressure limit (eg, a pressure cap).

[0132] In some forms, the operating parameters may include one or more alarm conditions.

[0133] In some forms, the one or more alarm conditions may include a lack of bubbles in a bubble CPAP therapy mode.

[0134] In some forms, the operating parameters may define a humidity level.

[0135] In some forms, the operating parameters may be one or more temperature or dew point set points for controlling the humidifier.

[0136] In some forms, the humidity level provided during the high flow mode may be higher than the humidity level provided during the bubble CPAP therapy mode.

[0137] In some forms, the operating parameters may also define flow limits in each mode.

[0138] In some forms, the controller is configured to detect bubbling of the bubbler, and if bubbling is detected, the controller selects a bubble CPAP therapy mode.

[0139] In some forms, the controller automatically switches modes when the bubbler is detected by bubbling.

[0140] In some forms, the user may select (optionally via a user interface) a high-flow therapy mode or a bubble CPAP therapy mode.

[0141] In some forms, the controller is configured to detect foaming by monitoring changes in the flow parameter signal.

[0142] In some embodiments, the flow parameter signal includes a flow signal, a pressure signal, or a combination thereof.

[0143] In some embodiments, the change is a change in amplitude of the flow parameter signal from a threshold value.

[0144] In some embodiments, the changes are analyzed in the frequency domain.

[0145] In some configurations, the same inhalation conduit can be used for both bubble CPAP and high-flow modes. The use of the same inhalation conduit for both modes reduces the number of components that need to be replaced when changing modes. Furthermore, this common inhalation conduit allows the same breathing device, with a blower and humidifier integrated into the housing, to be used for both bubble CPAP and high-flow modes. Furthermore, the integrated humidifier and blower within a common housing makes transitioning between bubble CPAP and high-flow modes simpler because a single device can be used, rather than the unique configuration of several components required in prior art systems. The present system provides a single breathing device that can be used to deliver both bubble CPAP and high-flow therapy, while only the interface needs to be replaced. There is no replacement of gas supply components; that is, there is no replacement of gas supply components, since a common breathing device can be used to deliver humidified gas.

[0146] In some forms, a high flow therapy mode kit for use with respiratory equipment includes one or more of: a non-contact patient interface, an inspiratory conduit.

[0147] In some forms, the high flow therapy mode kit is used in a high flow therapy mode (as described elsewhere herein).

[0148] In some forms, a bubble CPAP therapy mode kit for use with a respiratory device includes one or more of: a tight-fitting patient interface, an inhalation conduit, an exhalation conduit, and / or a bubbler.

[0149] In some forms, the bubble CPAP therapy mode kit is used in a bubble CPAP therapy mode (as described elsewhere herein).

[0150] These and other features, aspects, and advantages of the present disclosure will be described with reference to the drawings of several embodiments, which are intended to illustrate some embodiments generally and not to limit the disclosure. [Brief explanation of the drawings]

[0151] [Figure 1] 1 shows a schematic diagram of a conventional mechanism for using a respiratory device to provide bubble CPAP. [Figure 2] 1 shows a schematic representation of a respiratory apparatus with a flow generator for providing bubble CPAP. [Figure 3A] 1 illustrates a schematic representation of a high-flow respiratory system configured to provide respiratory therapy to a patient. [Figure 3B] FIG. 1 is a perspective front view of an exemplary high flow breathing apparatus with a humidification chamber in place. [Figure 3C] FIG. 3C is a perspective rear view of the breathing apparatus of FIG. 3B. [Figure 4] 3C illustrates an exemplary sensing chamber of the respiratory device of FIG. 3B. [Figure 5] 1 shows an exemplary block diagram for motor control in a respiratory device with a flow generator providing bubble CPAP. [Figure 6] 1 shows an exemplary flow chart for detecting foaming when providing bubble CPAP. [Figure 7] 1 shows a respiratory device having a high flow therapy controller program and a bubble CPAP therapy controller program. DETAILED DESCRIPTION OF THE INVENTION

[0152] While several examples are described below, those skilled in the art will recognize that the disclosure extends beyond the specifically disclosed examples and / or uses, and obvious modifications and equivalents thereof, and therefore, the scope of the disclosure disclosed herein is not intended to be limited to any particular examples described below.

[0153] Bubble CPAP therapy can cause changes or oscillations in the pressure of gas delivered to a patient connected to a positive pressure ventilation device. By submerging one end of the expiratory conduit in a water column, the resulting bubbles cause changes or ripples in the pressure of the gas delivered to the patient. The bubble CPAP system also provides a method for varying the average pressure of gas delivered to the patient by varying the level to which the end of the expiratory conduit is submerged in the water column. The level to which the end of the expiratory conduit is submerged can be kept constant to maintain the average pressure of gas delivered to the patient.

[0154] As shown in FIG. 1 , a conventional respiratory system for delivering bubble CPAP therapy may provide humidified and pressurized gas to a patient 119 through a patient interface, such as a mask 128 connected to an inhalation conduit 121 in FIG. 1 . The inhalation conduit 121 is connected to an outlet 112 of a humidification chamber 110 containing a volume of water 115. The volume of water 115 in the humidification chamber 110 is heated by a heating plate 113 located within the device housing 114, and water vapor begins to fill the volume of the chamber 110 above the water level. The water vapor may heat and humidify a flow of gas (e.g., air) delivered to the chamber 110 from a wall source 118 (see FIG. 1 ) through the inlet 116 of the chamber 110. The heated and humidified gas is exhausted from the outlet 112 of the humidification chamber 110 to the inhalation conduit 121. The inhalation conduit 121 may include a heater, such as heater wire 120 of FIG. 1, which heats the walls of the conduit to promote a substantially constant humidity profile along the inhalation conduit 121 and therefore reduce condensation of humidified gas within the inhalation conduit 121. The device may provide power to heat the inhalation conduit 121 and heating plate 113, such as with input from one or more sensors in the system, as described in more detail below.

[0155] The humidified gas may pass through an inhalation conduit 121 to a patient interface, such as a mask 128 attached to and / or fitted around the mouth, nose, and / or nares of the patient 119. The inhalation conduit 121 provides the patient 119 with a flow of gas, which may be ambient air, oxygen, a mixture of the two, or a mixture of ambient air and one or more supplemental gases. The gas may include a medication, which may be added by nebulization. The flow of gas through the inhalation conduit 121 may be delivered at a substantially constant flow rate in a bubble CPAP system. As shown in FIG. 1 , in the system, the flow of gas is provided by a wall source 118. The wall source 118 may deliver gas at a target flow rate to maintain the flow of gas delivered to the patient.

[0156] 1, excess gas may flow through an expiratory conduit 130 to a pressure regulator 134, which in the illustrated example is a bubbler. In a bubble CPAP system, the expiratory conduit 130 may terminate in an open end 136. This end 136 may be submerged in a volume of water 138 contained within the bubbler 134.

[0157] The bubbler can regulate pressure by submerging the terminal end 136 of the expiratory conduit 130 to a desired depth below a water level 140 in a volume of water 138. The terminal end 136 can also optionally be located on a short conduit that can be incorporated into the end of the expiratory conduit 130. The bubbler can function as a pressure regulator by venting gas whenever the pressure exceeds a desired level, maintaining the average or mean pressure at a target level. Bubble CPAP systems can also include a pressure relief valve 146 for venting excess gas when the pressure exceeds a desired level. The bubbler can also introduce oscillations in pressure, which can be clinically beneficial. Bubble CPAP therapy can reduce the incidence of acute lung injury and bronchopulmonary dysplasia compared to intubation and / or mechanical ventilation.

[0158] Overview of an Exemplary Flow Therapy Device FIG. 2 illustrates an exemplary respiratory apparatus including a flow generator 218 (also referred to as a blower, but which may include other types of flow generators disclosed herein) configured to provide bubble CPAP. Using a flow generator to generate a flow of gas may allow the respiratory apparatus to be used to provide bubble CPAP without a wall source, such as in situations where a wall source is not available. Furthermore, using a flow generator, e.g., a blower, within the respiratory apparatus allows the respiratory apparatus to draw in ambient air and provide it as the flow of gas for bubble CPAP. This makes the respiratory apparatus simpler and less expensive to use because there is no requirement for a gas reservoir or gas source, e.g., a wall source. Furthermore, a respiratory apparatus including a flow generator, e.g., a blower, is advantageous because ambient air is provided to the patient, eliminating the risk of running out of gas. This ensures that therapy is not interrupted due to a depleted gas source, since ambient air is plentiful. By incorporating a humidifier and, optionally, a supplemental gas blender into the flow generator (e.g., by incorporating the oxygen inlet port 358′ shown in FIG. 3C ), fewer separate components are required for the system, thereby simplifying its mechanism. Furthermore, the system occupies less space because there are fewer separate components connected by tubing. The described respiratory apparatus with an integrated humidifier and, optionally, an integrated supplemental gas blender, may occupy less space and reduce additional interconnecting tubing. Furthermore, the flow generator, integrated humidifier, and supplemental gas blender may be controlled by a single controller, thereby allowing for additional monitoring and control of various flow parameters, as will be described further. Furthermore, a respiratory apparatus including a flow generator may be capable of administering other forms of therapy, such as nasal high-flow therapy, thereby making it easier to transition between different types of respiratory support as the patient's condition changes and may also reduce the number of required consumable parts; for example, a common heated breathing tube may be used across multiple therapies, while only the patient interface needs to be replaced.

[0159] The breathing system of FIG. 2 may differ from the conventional bubble CPAP mechanism of FIG. 1 in that the gas flow is provided by a blower 218 integrated into at least the equipment housing 214. The system of FIG. 2 may also optionally include a supplemental gas source (e.g., an oxygen tank, an oxygen blender coupled to a flow meter, etc.) to control the oxygen concentration in the gas flow delivered to the patient 119. The supplemental gas source may be connected to the equipment housing 214 and / or the blower 218 (e.g., at the supplemental gas inlet). The supplemental gas source may also be configured to provide other types of supplemental gas, such as nitrogen. The supplemental gas source may be connected to an internal blender that blends the supplemental gas with ambient air to provide the gas flow to the patient. The concentration of the supplemental gas introduced into or present in the gas stream may be controlled. The system may include a temperature sensor, such as the temperature sensor 144 of FIG. 1, in the inspiratory conduit 121. The temperature sensor 144 may be coupled to and in electrical communication with a controller located within the equipment housing 214.

[0160] In some embodiments, the blower is configured to receive and mix the ambient gas and the supplemental gas.

[0161] The breathing system of Figure 2 may include a high-flow system. A schematic diagram of a high-flow system 10 is provided in Figure 3A. The breathing system 10 may include a main equipment housing 100. The main equipment housing 100 may include a flow generator 11, which may be in the form of a motor / impeller arrangement (such as a blower), an optional humidifier or humidification chamber 12, a controller 13, and a user interface 14. The user interface 14 may include a display and one or more input devices, such as one or more buttons, a touchscreen, a combination of a touchscreen and one or more buttons, etc. The controller 13 may include one or more hardware and / or software processors and may be configured or programmed to control components of the respiratory apparatus, including but not limited to, operating the flow generator 11 to generate a flow of gas for delivery to the patient, operating the humidifier 12 (if present) to humidify and / or heat the gas flow, receiving user input from a user interface 14 for reconfiguration and / or user-defined operation of the respiratory system 10, and outputting information to a user (e.g., on a display), which may be a patient, a healthcare professional, etc.

[0162] Continuing with reference to FIG. 3A , the patient breathing conduit 16 is coupled to a gas flow outlet 21 of the main equipment housing 100 of the respiratory system 10 and may be coupled to a patient interface 17. The patient interface may be a non-sealing interface, such as a nasal cannula with a manifold 19 and nasal prongs 18, to deliver high-flow therapy. The nasal cannula does not seal perfectly against the user's nares, allowing exhaled gases to leak around the nasal prongs when the user exhales. The patient breathing conduit 16 may also be coupled to a sealing interface, such as a face mask, oral-nasal mask, nasal mask, nasal pillow mask, or nasal cannula, to deliver bubble CPAP. The patient interface may also optionally include an endotracheal tube, a tracheostomy interface, or the like.

[0163] The gas flow is generated by the flow generator 11 and may be humidified before being delivered to the patient through the patient interface 17 via the patient conduit 16. The controller 13 may control the flow generator 11 to generate a gas flow at a desired rate and / or one or more valves to control the mixture of air and oxygen or other breathable gas. The controller 13 may control a heating element (if present) in the humidification chamber 12 to heat the gas to a desired temperature and / or achieve a desired level of temperature and / or humidity for delivery to the patient. The patient conduit 16 may have a heating element 16a, e.g., a heater wire, for heating the gas flow passing to the patient. The heating element 16a may also be under the control of the controller 13. The heating element 16a heats the gas to reduce and / or prevent condensation within the patient conduit 16.

[0164] System 10 may use one or more ultrasound transducers, one or more flow sensors, such as a thermistor flow sensor, one or more pressure sensors, one or more temperature sensors, one or more humidity sensors, or other sensors in communication with controller 13 to monitor gas flow characteristics and / or operate system 10 to provide a suitable therapy. Gas flow characteristics may include gas concentration, flow rate, pressure, temperature, humidity, etc. Sensors 3a, 3b, 3c, 20, 25, such as pressure, temperature, humidity, and / or flow sensors, may be located at various locations within main equipment housing 100, patient conduit 16, and / or patient interface 17. Controller 13 may receive output from the sensors to assist the controller in determining a suitable target temperature, flow rate, and / or pressure gas flow to operate respiratory system 10 to provide a suitable therapy. Providing a suitable therapy may include meeting the patient's required inspiration volume. Suitable therapy flow rates, such as high flow therapy flow rates and / or flow rates that meet or exceed the patient's required inspiratory volume, are described below.

[0165] System 10 may include a wireless data transmitter and / or receiver, or transceiver 15, allowing controller 13 to wirelessly receive data signals 8 from motion sensors and / or control various components of system 10. Additionally or alternatively, data transmitter and / or receiver 15 may transmit data to a remote server or allow remote control of system 10. In one example, the remote server may record patient usage data, such as usage of a bubble CPAP system or usage of a high-flow system. Usage may include usage time and / or flow rate and humidity levels (e.g., dew point). System 10 may also include wired connections, for example, using cables or communication lines, allowing controller 13 to receive data signals 8 from motion sensors and / or control various components of system 10.

[0166] The system 10 may be powered from a mains voltage.

[0167] In some embodiments, the system may include an auxiliary power source (eg, a battery).

[0168] In some embodiments, the system may include a battery. The battery may provide the primary power source for the system or may act as a backup power source when the primary power source is unavailable. This is advantageous because it allows therapy to occur continuously, i.e., gas may continue to be delivered to the patient even if mains power is lacking or unavailable. This is advantageous because therapy may be maintained for a period of time for neonates or infants, thereby reducing the chance of physiological deterioration or injury to these patients due to loss of therapy.

[0169] The battery may increase the portability of the system, allowing it to be used in situations where mains voltage power is not available.

[0170] High-flow therapy, as described herein, shall be given its typical ordinary meaning as understood by those skilled in the art, thereby generally referring to a respiratory assistance system that delivers a targeted flow of humidified respiratory gas through an intentionally loose patient interface, generally at a flow rate intended to meet or exceed the patient's inspiratory flow rate. Typical patient interfaces include, but are not limited to, nasal or tracheal patient interfaces. Typical flow rates for adults often range from about 15 liters per minute to about 60 liters per minute or more. Typical flow rates for pediatric patients (such as neonates, infants, and children) often range from about 1 liter per minute per kilogram of patient weight to about 3 liters per minute per kilogram of patient weight or more. High-flow therapy may also, optionally, include gas mixture compositions containing supplemental oxygen and / or the administration of therapeutic medications. High-flow therapy is often referred to as nasal high flow (NHF), humidified high-flow nasal cannula (HHFNC), high flow nasal oxygen (HFNO), high flow therapy (HFT), or tracheal high flow (THF), among other common names.

[0171] As used herein, "high flow" therapy may refer to the administration of gases to a patient's airways at a relatively high flow rate, optionally meeting or exceeding the patient's required maximum inspiratory capacity. Some exemplary flow rates used to achieve "high flow" may be any of the flow rates listed below. For example, in some forms, for an adult patient, "high flow therapy" may refer to the delivery of one or more gases to a patient at a flow rate of about 10 liters per minute (10 LPM) or greater, e.g., from about 10 LPM to about 100 LPM, or from about 15 LPM to about 95 LPM, or from about 20 LPM to about 90 LPM, or from about 25 LPM to about 85 LPM, or from about 30 LPM to about 80 LPM, or from about 35 LPM to about 75 LPM, or from about 40 LPM to about 70 LPM, or from about 45 LPM to about 65 LPM, or from about 50 LPM to about 60 LPM. In some embodiments, for neonatal, infant, or pediatric patients, "high flow therapy" can refer to the delivery of one or more gases to a patient at a flow rate of greater than 1 LPM, e.g., from about 1 LPM to about 25 LPM, or from about 2 LPM to about 25 LPM, or from about 2 LPM to about 5 LPM, or from about 5 LPM to about 25 LPM, or from about 5 LPM to about 10 LPM, or from about 10 LPM to about 25 LPM, or from about 10 LPM to about 20 LPM, or from about 10 LPM to 15 LPM, or from about 20 LPM to 25 LPM. High flow therapy devices for adult, neonatal, infant, or pediatric patients can deliver one or more gases to a patient at a flow rate of from about 1 LPM to about 100 LPM, or any of the subranges outlined above.

[0172] 3B and 3C show an exemplary respiratory device of the respiratory system 10. The device may include a housing 300 enclosing a flow generator. The flow generator may include a motor and / or sensor module. The motor and / or sensor module may be permanently attached to the main housing 300. The motor and / or sensor module may also optionally be removable from the main housing 300. The housing 300 may include a humidifier or humidifier chamber space 318 for receiving a removable humidifier chamber 310. The removable humidifier chamber 310 contains a suitable liquid, such as water, for heating and humidifying gases delivered to the patient. The humidifier chamber 310 may be fluidly coupled to the device housing 300 with a linear sliding motion into the chamber space 318. A gas outlet port 322 may establish fluid communication between the motor and / or sensor module and the inlet 306 of the chamber 310.

[0173] The heated and humidified gas flows out the outlet 308 of the chamber 310 and into the humidified gas return 340, which may include a removable elbow. The removable elbow may further include a patient outlet port 344 for coupling to an inhalation conduit, such as the inhalation conduit 16 of FIG. 3A, to deliver gas to the patient interface 17. The gas outlet port 322, the humidified gas return 340, and the patient outlet port 344 may each include a seal, such as an O-ring seal or a T-seal, to provide a sealed gas passage between the device housing 300, the humidification chamber 310, and the inhalation conduit. The floor of the chamber space 318 within the housing 300 may include a heater arrangement, such as a heating plate or other suitable heating element(s), to heat water in the humidification chamber 310 for use during the humidification process. The elbow may include one or more integrated sensors. For example, the elbow may include a pair of embedded temperature sensors.

[0174] As shown in FIG. 3C , the device may include an arrangement for enabling the flow generator to deliver air, oxygen (or an alternative supplemental gas), or a suitable mixture thereof, to the humidification chamber 310 and thereby to the patient. This arrangement may include an air inlet 356′ in the rear wall 322 of the housing 300. The device may include a separate oxygen inlet port 358′. In the illustrated form, the oxygen inlet port 358′ may be positioned adjacent one side of the housing 300 at its rear end. The oxygen port 358′ may be connected to an oxygen source, such as a tank, or an oxygen blender. The oxygen inlet port 358′ may be in fluid communication with a valve. The valve may preferably be a solenoid valve capable of controlling the amount of oxygen added to the gas flow delivered to the humidification chamber 310.

[0175] The housing 300 may include a suitable electronic board, such as a sensing circuit board. The electronic board may include or be in electrical communication with suitable electrical or electronic components, such as, but not limited to, a microprocessor, capacitors, resistors, diodes, operational amplifiers, comparators, and switches. One or more sensors may be used in conjunction with the electronic board. Components of the electronic board (such as, but not limited to, one or more microprocessors) may perform the function of the controller 13 of the respiratory apparatus. One or both of the electronic boards may be in electrical communication with the electrical components of the system 10, including, but not limited to, a display unit and user interface 14, motors, valves, and heater plates, to operate the motors to provide the desired gas flow rate, humidify and heat the gas stream to the appropriate levels, and supply the appropriate amount of oxygen (or an alternative supplemental gas) to the gas stream.

[0176] As mentioned above, operational sensors, such as flow, temperature, humidity, and / or pressure sensors, may be located at various locations within the respiratory equipment, patient conduit 16, and / or cannula 17. An electronics board may be in electrical communication with these sensors. Output from the sensors may be received by the controller 13 to assist the controller 13 in operating the respiratory system 10 to deliver optimal therapy, including meeting required inspiratory volumes. One or more sensors (e.g., Hall-effect sensors) may be used to measure the motor speed of the flow generator motor. The motor may include a brushless DC motor, from which motor speed may be measured without the use of a separate sensor. For example, during operation of a brushless DC motor, back-EMF may be measured from the non-energized windings of the motor, from which motor position may be determined, which may then be used to calculate motor speed. Additionally, a motor driver may be used to measure motor current, which may be used together with the measured motor speed to calculate motor torque. The motor may also include a low-inertia motor.

[0177] Room air can enter the flow generator through an inlet port, such as air inlet port 356' in FIG. 3C. The flow generator can operate at a motor speed greater than 1,000 RPM and less than 30,000 RPM, greater than 2,000 RPM and less than 21,000 RPM, greater than 4,000 RPM and less than 15,000 RPM, or any of the values ​​between these values. Operation of the flow generator mixes the gases entering the flow generator, e.g., the motor and / or sensor chamber, through the inlet port. Using the flow generator as a mixer can reduce pressure drops that might otherwise occur in systems with separate mixers, such as static mixers including baffles, because mixing requires energy.

[0178] As shown in FIG. 4 , the mixed air may exit the flow generator and enter a flow path 402 in a sensor chamber 400, which may be located in a motor and / or sensor module. A sensing circuit board 404 including a sensor, such as an ultrasonic sensor 406 and / or a heated thermistor flow sensor, may be positioned within the sensor chamber 400 such that the sensing circuit board is at least partially immersed in the gas flow. At least a portion of the sensor on the sensing circuit board may be positioned within the gas flow to measure gas properties within the flow. After passing through the flow path 402 in the sensor chamber 400, the gas may exit to the humidification chamber 310.

[0179] Positioning the sensor downstream of the flow generator may increase the accuracy of measurements, such as measurements of gas component concentrations, including oxygen concentration, compared to systems in which the sensor is positioned upstream of the flow generator and / or mixer. Such positioning may provide a repeatable flow profile. Furthermore, positioning the sensor downstream of a combined flow generator and mixer avoids the effects of pressure drops that would otherwise occur when sensing occurs upstream of a flow generator and a separate mixer. Also, by immersing at least a portion of the sensing circuit board and sensor in the flow path, the sensor, which is immersed in the flow, may increase measurement accuracy because it is subject to the same conditions, e.g., temperature and pressure, as the gas flow and therefore better represents the gas flow characteristics.

[0180] As shown in Figure 4, the flow path 402 can have a curved shape. The flow path 402 can be configured to have a curved shape without sharp turns. The flow path 402 can have curved ends with straight sections between the curved ends. A curved flow path shape can reduce the pressure drop of the gas flow without reducing flow measurement sensitivity by partially coinciding the flow path with the measurement area to form the measurement portion of the flow path.

[0181] The sensing circuit board 404 may include sensors, such as acoustic transmitters and / or receivers, humidity sensors, temperature sensors, thermistors, etc. Gas flow rate may be measured using at least two different types of sensors. The first type of sensor may include a thermistor, which can determine the flow rate by monitoring heat transfer between the gas flow and the thermistor. A thermistor flow sensor can drive a thermistor at a constant target temperature within the flow as the gas flows around and past the thermistor. The sensor can measure the amount of power required to maintain the thermistor at the target temperature. The target temperature may be configured to be higher than the temperature of the gas flow, such that more power is required to maintain the thermistor at the target temperature at higher flow rates.

[0182] The thermistor flow sensor may also maintain multiple (e.g., two, three, or more) constant temperatures on the thermistor to prevent the difference between the target temperature and the gas flow temperature from becoming too small or too large. Multiple different target temperatures can make the thermistor flow sensor accurate across a large temperature range of gas. For example, the thermistor circuit may be configured to switch between two different target temperatures so that the temperature of the gas flow always falls within a certain range (e.g., not too close and not too far) of one of the two target temperatures. The thermistor circuit may be configured to operate at a first target temperature of about 50°C to about 70°C, or about 66°C. The first target temperature may be associated with a desired flow temperature range of about 0°C to about 60°C, or about 0°C to about 40°C. The thermistor circuit may be configured to operate at a second target temperature of about 90°C to about 110°C, or about 100°C. The second target temperature can be related to a desired flow temperature range of about 20°C to about 100°C, or about 30°C to about 70°C.

[0183] The controller may be configured to adjust the thermistor circuit to vary between at least a first target temperature mode and a second target temperature mode by connecting or bypassing resistors in the thermistor circuit. The thermistor circuit may be arranged in a Wheatstone bridge configuration including a first voltage divider arm and a second voltage divider arm. The thermistor may be located in one of the voltage divider arms. More details about thermistor flow sensors are described in International Publication No. WO2018052320A2, the entire contents of which are incorporated herein by reference.

[0184] A second type of sensor may include an acoustic (e.g., ultrasonic) sensor assembly. Acoustic sensors, including acoustic transmitters and / or receivers, may be used to measure the time of flight of acoustic signals to determine the velocity and / or composition of gases, which may be used in flow therapy devices. In one ultrasonic sensing (including ultrasonic transmitters and / or receivers) topology, a driver causes a first sensor, e.g., an ultrasonic transducer, to generate an ultrasonic pulse in a first direction. A second sensor, e.g., a second ultrasonic transducer, receives the pulse and provides a measurement of the time of flight of the pulse between the first and second ultrasonic transducers. Using this time-of-flight measurement, the speed of sound in the gas flow between the ultrasonic transducers can be calculated by a processor or controller of the respiratory device. The second sensor may also transmit, and the first sensor may receive, the pulse in a second direction opposite the first direction, providing a second measurement of the time of flight, allowing a characteristic of the gas flow, e.g., flow rate or velocity, to be determined. In another acoustic sensing topology, acoustic pulses transmitted by an acoustic transmitter, e.g., an ultrasonic transducer, can be received by an acoustic receiver, such as a microphone. A more detailed acoustic flow sensor is described in WO2017095241A3, which is incorporated herein by reference in its entirety. Acoustic pulses can be transmitted along a gas flow path, thereby allowing the acoustic sensor to be used to measure the flow rate or velocity of the gas.

[0185] Readings from both the first and second types of sensors can be combined to determine a more accurate flow measurement. For example, a previously determined flow rate and one or more outputs from one of the types of sensors can be used to determine a predicted current flow rate. The predicted current flow rate can then be updated using one or more outputs from the other end of one of the first and second types of sensors to calculate a final flow rate.

[0186] The breathing system may be configured to provide high-flow or bubble CPAP therapy.

[0187] The respiratory device may be switchable between a high flow therapy mode and a bubble CPAP therapy mode.

[0188] In the high flow therapy mode, the respiratory device is configured to provide high flow therapy.

[0189] In the bubble CPAP therapy mode, the respiratory device is configured to provide bubble CPAP therapy.

[0190] High flow therapy is nasal high flow therapy.

[0191] In the high flow therapy mode, the system includes a loose-fitting patient interface coupled to the inhalation conduit 121 .

[0192] The loose patient interface may be a nasal cannula.

[0193] In use, the nasal cannula is positioned on the user's face to deliver gas to the user's nostrils.

[0194] In the bubble CPAP therapy mode, the system includes a tight fitting patient interface coupled to an inhalation conduit 121 and an exhalation conduit 130 coupled to the tight fitting patient interface.

[0195] The expiratory conduit 130 is coupled to a pressure regulator to regulate the pressure within the patient interface and / or the patient's airway.

[0196] As explained in more detail above, the pressure regulator includes a chamber with a column of water, and the expiratory conduit 130 is submerged in the column of water. The pressure delivered to the user is defined or set by the depth to which the expiratory conduit 130 is submerged in the column of water.

[0197] The inhalation conduit 121 may be common to both the high flow and bubble CPAP therapy modes.

[0198] The same inhalation conduit that can be used in both modes reduces the number of components that need to be replaced when changing modes.

[0199] Furthermore, this common inhalation conduit allows the same respiratory device, including a blower and humidifier integrated into the housing, to be used for both bubble CPAP and high-flow modes. Furthermore, the integrated humidifier and blower within a common housing makes the transition between bubble CPAP and high-flow modes simpler, as a single device can be used rather than a unique configuration of several components as required in prior art systems.

[0200] The system provides a single breathing apparatus that can be used to deliver both bubble CPAP therapy and high-flow therapy, requiring only interface changes: no changes to gas delivery components, i.e., no exchange of gas delivery components, as the common breathing apparatus can be used to deliver humidified gases.

[0201] As shown in FIG. 7, the controller 13 may include a high flow therapy control program 210 associated with a high flow therapy mode.

[0202] As shown in FIG. 7, the controller 13 may include a bubble CPAP therapy control program 211 associated with the bubble CPAP therapy mode.

[0203] In some embodiments, the high-flow therapy mode may use a high-flow therapy controller. Optionally, the high-flow therapy controller may be configured to execute high-flow therapy control program 210.

[0204] In some embodiments, the bubble CPAP therapy mode may use a bubble CPAP therapy controller. Optionally, the bubble CPAP therapy controller may be configured to execute a bubble CPAP therapy control program 211.

[0205] The controller 13 is configured to select and apply the program 210, 211 corresponding to the selected operating mode.

[0206] Each of the high flow therapy control program 210 and the bubble CPAP therapy control program 211 defines corresponding operating parameters.

[0207] In some forms, the operating parameters may include one or more motor speeds or pressure limits (e.g., upper pressure limits), as described in more detail below.

[0208] The operating parameters may include one or more alarm conditions.

[0209] The one or more alarm conditions may include a lack of bubbles in a bubble CPAP therapy mode.

[0210] In some embodiments, an alarm may be activated when a lack of effervescence is detected for more than a threshold period.

[0211] The operating parameters may define a humidity level.

[0212] The operating parameters may be one or more temperature or dew point set points for controlling the humidifier.

[0213] The humidity level provided during the high flow mode may be higher than the humidity level provided during the bubble CPAP therapy mode.

[0214] The operating parameters may also define flow limits corresponding to each mode.

[0215] The controller may be configured to detect bubbling of the bubbler, and if bubbling is detected, the controller selects a bubble CPAP therapy mode.

[0216] The controller may select a bubble CPAP therapy mode once bubbling is detected for a predetermined period of time.

[0217] The controller may, once bubbling is detected (optionally for a predetermined time), present a message to the user to consider changing the mode to bubble CPAP therapy mode.

[0218] The controller may automatically switch the mode to bubble CPAP therapy mode if the bubbler is detected by bubbling.

[0219] The user may select (optionally via a user interface) a high flow therapy mode or a bubble CPAP therapy mode.

[0220] The detection of foaming may be as described elsewhere herein.

[0221] Control of FdO2 As mentioned above, the flow generator can be used as a mixer for oxygen and / or other breathable gases. A flow generator that draws in ambient air can mix the air with oxygen from an oxygen source, which can be from a high pressure or low pressure source.

[0222] When receiving oxygen from a low-pressure source, which may include an oxygen canister or tank, a wall source, or an oxygen concentrator, the respiratory device may receive a constant flow of oxygen. This oxygen may then be mixed with ambient air. The percentage of oxygen (FdO2) in the gas delivered to the patient may depend on the set flow rate of oxygen from the low-pressure source and the total flow rate generated by the device. The device may measure the FdO2 and display it on a display.

[0223] When receiving oxygen from a high-pressure source, which may include an oxygen canister or tank, an oxygen wall source, or an oxygen concentrator, the device can control the flow rate of oxygen by controlling a valve to the oxygen inlet port described herein. FdO2 can depend on the flow rate of oxygen through the valve (which may further depend on the valve's opening state) and the total flow rate generated by the device. A user, such as a clinician, can set a target FdO2 on the user interface of the display, and the device then controls the valve opening based on the target FdO2 and the measured FdO2 to achieve the desired oxygen percentage. Oxygen concentration can be measured by various sensors, such as the ultrasonic sensor described above. Exemplary methods for measuring oxygen concentration are described in more detail in International Publication No. WO 2013151447 A1, the contents of which are incorporated herein by reference in their entirety.

[0224] Flow Control As mentioned above, bubble CPAP generally involves delivering a constant flow of gas to a patient.

[0225] In some forms, the parameters of the blower and / or motor may be controlled by the flow generator to maintain the flow rate at a desired level.

[0226] For example, the flow generator (or eg, a controller) may control one or more of the motor speed, motor current, and / or motor voltage to a target motor speed, target motor current, and / or target motor voltage.

[0227] In some forms, example respiratory devices disclosed herein may measure the flow rate of gas and, based at least in part on the flow rate measurement, control the motor speed of the flow generator to maintain a constant flow rate at a desired level.

[0228] The flow generator may, for example, control the motor speed of the motor to a target motor speed. The motor speed may correspond to a desired flow rate, i.e., a target flow rate. In one example, the motor speed is a control parameter because feedback from the motor speed may be read more quickly by the controller compared to feedback from a sensor, e.g., a flow sensor downstream of the blower, allowing the controller to achieve a faster response. Alternatively, the controller may use flow readings from the flow sensor to control the motor.

[0229] The controller controls the blower to a target motor speed or a target flow or both. The controller preferably provides a control signal to control or vary the current or voltage or power supplied to the blower motor to achieve the target motor speed or target flow rate.

[0230] As a further alternative, the controller may control the motor using a combination of motor speed and flow rate. In this example, the controller may control the motor using feedback from the motor speed readings and flow readings from the flow sensor to achieve a target motor speed and / or target flow rate.

[0231] Measurement of flow rate may be performed using one or more flow sensors. As mentioned above, examples of sensors capable of measuring gas flow rate include ultrasonic sensors and heated thermistors. Ultrasonic sensors may provide a faster signal but are generally less accurate than heated thermistors. Heated thermistors may provide a more accurate signal but may not respond to small, rapid changes in flow. In the nasal high flow systems described herein, the flow sensor flow signal needs to be filtered before being used to control the flow generator. This is because a patient receiving nasal high flow may cause changes in flow by coughing, talking, repositioning the cannula, etc. In this case, it may be desirable for the device to not make sudden changes to motor speed based on these events.

[0232] However, these patient-induced fluctuations in flow are less common when implementing bubble CPAP. Therefore, flow control can be designed to be more responsive, accounting for small leaks in the system, partial blockages, and / or dynamic changes in the patient's respiratory volume requirements. Flow control can be achieved by using a shorter filter in the flow measurement than in nasal high-flow therapy. Additionally and / or alternatively, the controller can use flow measured by an ultrasonic sensor to provide a much faster signal. Additionally and / or alternatively, the controller can use a combination of flow measured by an ultrasonic sensor and a heated thermistor. The controller can use the ultrasonic sensor to detect higher frequency changes in flow and the heated thermistor to compensate for less accurate measurements made by the ultrasonic sensor, which may be less accurate than when measured by a heated thermistor. The controller can also use one or more sensors of other types to measure flow and / or pressure. The pressure and / or flow sensor can include a single sensor.

[0233] Once the system controller receives a flow signal from one or more flow sensors disclosed herein, the controller can measure the flow rate from the flow signal. The system controller can determine the difference between the target flow rate and the measured flow rate. The difference can be input to a PID controller. The PID controller can output a command to vary the motor speed of the flow generator based on the input. In one example, the PID controller can output a current or voltage or power to the motor to control the motor speed.

[0234] Control of flow rate may also be based on pressure measurements. In conventional bubble CPAP systems, a pressure relief valve may be placed between the flow source and the patient. The pressure relief valve is a passive valve that may open at a set pressure to release a portion of the gas flow, thereby limiting the pressure of the gas delivered to the patient.

[0235] By using a flow generator to provide the gas flow, the pressure limit can be implemented via software in the flow generator motor speed. The high-flow systems described herein may not include an additional valve for venting excess flow. Controlling the motor speed may provide more precise control of pressure than venting gas through a pressure relief valve, because the flow generator motor speed can be controlled directly based on the measured pressure. Use of a breathing system (i.e., breathing equipment) with a flow generator as described herein does not require a pressure relief valve, because the flow generator can be controlled to slow down the motor speed to generate less pressure if a pressure limit is reached. The system is simplified and requires fewer components because it does not require a pressure relief valve and does not require a gas source.

[0236] FIG. 5 shows an example block diagram of motor control by the appliance controller. The appliance controller may receive input 502 from one or more pressure sensors. The controller may measure the pressure delivered to the patient from the pressure sensor input. The pressure sensor may be located downstream of the flow generator. For example, the pressure sensor may be located at or near the patient interface. The pressure sensor may also be located immediately after the flow generator. The pressure delivered to the patient may be determined by taking the difference between ambient pressure and the absolute pressure downstream of the flow generator. The pressure delivered to the patient may be estimated by measuring the pressure in the main appliance housing downstream of the flow generator and calculating the pressure drop along the inspiratory conduit. One or more pressure sensors may also be located elsewhere in the gas flow. Pressure measurements may also, optionally, be calculated, at least in part, based on the flow rate. The pressure sensor may include a gauge pressure sensor, or alternatively, two absolute pressure sensors. The gauge pressure sensor may directly measure the difference between the absolute pressure downstream of the flow generator and ambient pressure. In a system with two absolute pressure sensors, one sensor may be located downstream of the flow generator to measure the absolute pressure downstream of the flow generator, and the other sensor may be located at a different point to measure the ambient pressure. The controller may determine the pressure delivered to the patient by determining the difference between the pressure measurements made by the two absolute pressure sensors.

[0237] In decision logic 504, the controller may compare the measured pressure (e.g., as described above) to a predetermined pressure limit. The pressure limit may be set to exceed the maximum pressure to which the bubbler can be set. In some forms, the bubbler may be set to a maximum pressure of approximately 10 cmH2O, and the pressure limit for pressure control may be set to, for example, approximately 12 cmH2O, approximately 13 cmH2O, approximately 14 cmH2O, approximately 15 cmH2O, approximately 16 cmH2O, approximately 17 cmH2O, or approximately 18 cmH2O.

[0238] The pressure limit may be based on ambient pressure.

[0239] The relationship between the pressure limit and the ambient pressure may be linear or non-linear.

[0240] The pressure limit may be based on a fixed amount or percentage above ambient pressure.

[0241] A pressure limit that is based on ambient pressure allows for compensation for ambient pressure, which can be important in bubble CPAP systems when the maximum bubbler pressure is achieved by ambient pressure, so the effect of ambient pressure can be incorporated into the determination of the pressure limit.

[0242] In some embodiments, the pressure limit may be based on a predetermined ambient pressure (eg, a preset, unmeasured ambient pressure).

[0243] The pressure limit may be set by the user.

[0244] If the measured pressure falls below a limit value, the controller may adjust the motor speed based on the output of a flow-based PID controller 506 described herein. The controller may input the difference between the target or set flow rate (as set by a user) and the measured flow rate into the PID controller. The controller may output as output 510 the motor speed determined by the PID controller configured to maintain the target flow rate.

[0245] If the measured pressure exceeds the pressure limit, the controller may execute a pressure upper limit algorithm 508. The pressure upper limit algorithm 508 may slow the target motor speed according to a set amount, a set deceleration rate, a variable deceleration rate, or using pressure-based PID control. The controller may output the reduced motor speed as the control output 510. The target motor speed is reduced with each iteration of the motor control as shown in FIG. 5 until the measured pressure falls below the pressure limit. The target motor speed may be reduced at a constant rate or a variable rate.

[0246] In some embodiments, the pressure upper limit algorithm 508 may reduce the target motor speed (eg, as part of a proportional control) in proportion to the amount the measured pressure exceeds the pressure limit.

[0247] In some embodiments, the pressure upper limit algorithm 508 may slow down the target motor speed to reduce the measured pressure below the pressure limit within a predetermined period of time. For example, the pressure upper limit algorithm 508 may slow down the target motor speed to reduce the measured pressure below the pressure limit within about 2 to about 20 seconds, or within about 5 to about 15 seconds, or within about 10 seconds.

[0248] In some embodiments, the set deceleration rate of the target motor speed may be set high enough to reduce the measured pressure below the pressure within a predetermined time.

[0249] Additionally and / or alternatively, the device may output a visual, audible, and / or tactile alarm when the measured pressure exceeds a threshold value.

[0250] In some forms, the device may prevent the motor from exceeding a set speed, further preventing too high a pressure from being delivered to the patient. The motor speed limit may act as a fail-safe in situations where one or more sensors output false pressure readings and / or are otherwise defective. That is, two checks may be available to prevent the pressure of the gas flow from exceeding a predetermined maximum. One check may be an upper pressure limit. The other check may be a maximum motor speed limit if the pressure sensor reading is erroneous.

[0251] In some embodiments, the motor speed limit may vary.

[0252] The motor speed limit may be based on ambient pressure, which allows, for example, the motor speed limit to take into account, for example, the altitude of the equipment.

[0253] The relationship between the motor speed limit and the ambient pressure may be linear or non-linear.

[0254] In some embodiments, the motor speed limit may be a first motor speed (eg, 10,000 RPM) when the ambient pressure is a first ambient pressure (eg, about 101 kPa (ie, about sea level)).

[0255] In some embodiments, the motor speed limit may be a second motor speed (e.g., about 15,000 RPM) when the ambient pressure is a second ambient pressure (e.g., about 79.5 kPa (i.e., about 2000 meters above sea level) or, for example, about 70.1 kPa (i.e., about 3000 meters above sea level).

[0256] The motor speed limit may vary between a first motor speed and a second motor speed between a first ambient pressure and a second ambient pressure.

[0257] In some embodiments, the motor speed limit may be further based on the ambient temperature.

[0258] Foam detection The flow generator of a high-flow device may also be configured to detect the presence of bubbles in the bubbler. Bubbles can be useful in indicating that the system is operating correctly. For example, a temporary lack of bubbles may indicate that the patient's peak inspiratory flow rate exceeds the flow rate delivered by the device at that moment. Furthermore, a prolonged lack of bubbles may indicate a leak in the gas path, e.g., in the breathing circuit.

[0259] Foaming may be detected by detecting the presence of oscillations in pressure and / or flow. In breathing systems where the flow rate is controlled by an appliance controller, the controller may determine the presence of foaming using a pressure signal input, for example, from a pressure sensor as disclosed herein.

[0260] FIG. 6 shows an exemplary flowchart for determining whether bubbling can be detected. While a pressure signal is used as an example in FIG. 6, the flowchart can also be applied to flow signals and / or combinations of pressure and flow signals. In step 602, the controller can receive a pressure signal from a pressure sensor. In step 603, the pressure signal can optionally be filtered so that the measured amplitude is the amplitude of the actual pressure signal. In step 604, the controller can determine the amount of variation in the pressure signal from an average value of the pressure of the gas flow delivered to the patient (e.g., as measured by one or more pressure sensors disclosed herein). In steps 606 and 608, the controller can determine whether oscillations are present in the pressure signal. Oscillation is present if the amount of variation exceeds a certain magnitude 606 and a certain frequency 608. For example, the pressure signal can be filtered using a high-pass filter with a cutoff frequency of about 5 Hz or a band-pass filter with a cutoff frequency of about 5 Hz to about 20 Hz. The certain magnitude (e.g., as measured peak-to-peak) can be about 0.25 cmH2O. The threshold magnitude may be a single threshold or may vary depending on the set flow rate or pressure. If such oscillations are present, the controller may output an indication in step 610 that foaming is considered to be occurring. In the example provided herein, if oscillations are present in the filtered signal with a magnitude greater than approximately 0.25 cmH2O (e.g., measured peak-to-peak), the controller may determine that foaming is detected. The controller may determine that foaming cannot be determined if the magnitude is less than approximately 0.25 cmH2O. Alternatively, the controller may analyze the power spectrum in the frequency domain. If there is sufficient power in that frequency band, the controller may determine that foaming is detected. Otherwise, the controller may determine that foaming is not detected. The controller may then return to step 602. If the change is less than or equal to the magnitude limit in step 606 and / or if the change is less than or equal to the frequency limit in step 608, the controller may return to step 602 and repeat the foaming detection process.The controller may optionally output a visual, audible, and / or tactile alarm of the absence of foaming in steps 612, 614.

[0261] The controller may also optionally monitor the duration for which no foaming is considered to be present, and if no foaming is detected for a predetermined duration, for example, about 5 seconds, about 10 seconds, about 15 seconds, about 20 seconds, or longer, the controller may optionally output a message instructing the user to check for leaks in the gas path of the breathing system.

[0262] Terminology While the present disclosure has been described in terms of several embodiments and examples, those skilled in the art will understand that the present disclosure extends beyond the specifically disclosed embodiments to other alternative embodiments and / or uses, as well as obvious modifications and equivalents thereof. Moreover, while several variations of the embodiments of the present disclosure have been shown and described in detail, other modifications that are within the scope of the present disclosure will be readily apparent to those skilled in the art. It is also contemplated that various combinations or subcombinations of specific features and aspects of the embodiments may be made and still fall within the scope of the present disclosure. For example, features described above in connection with one embodiment may be used with different embodiments described herein, and the combinations will still fall within the scope of the present disclosure. It should be understood that various features and aspects of the disclosed embodiments may be combined with or substituted for one another to form various aspects of the embodiments of the present disclosure. Therefore, it is not intended that the scope of the present disclosure herein be limited to the specific embodiments described above. Therefore, unless otherwise specified or clearly contradictory, each embodiment of the present invention may include, in addition to its essential features described herein, one or more features, as described herein, from each of the other embodiments of the present invention disclosed herein.

[0263] It is understood that any feature, material, property, or group described in connection with a particular aspect, embodiment, or example applies to any other aspect, embodiment, or example described in this section or elsewhere in this specification, unless inconsistent. All features disclosed herein (including any accompanying claims, abstracts, and drawings), and / or all steps of any method or process so disclosed, may be combined in any combination, except combinations in which at least some of such features and / or steps are mutually exclusive. The scope of protection is not limited to the details of any of the above-described embodiments. The scope of protection extends to any novel, or any novel combination of, features disclosed herein (including any accompanying claims, abstracts, and drawings), or to any novel, or any novel combination of steps of any method or process so disclosed.

[0264] Furthermore, certain features that are described in this disclosure in the context of separate implementations may also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation may also be implemented in multiple implementations, separately or in any suitable subcombination. Furthermore, while features may be described above as taking on certain combinations, one or more features from a claimed combination may, in some cases, be deleted from the combination, and the combination may be claimed as a subcombination or a variation of the subcombination.

[0265] Furthermore, while operations may be shown in the figures or described herein in a particular order, such operations need not be performed in the particular order or sequence shown, nor may all operations be performed to achieve a desired result. Other operations not shown or described may be incorporated into the example methods and processes. For example, one or more additional operations may be performed before, after, simultaneously with, or between any of the described operations. Furthermore, operations may be rearranged or reordered in other implementations. Those skilled in the art will recognize that in some embodiments, the actual steps performed in the described and / or disclosed processes may differ from those shown in the figures. Depending on the embodiment, some of the steps described above may be removed, and others may be added. Furthermore, features and attributes of the specific embodiments disclosed above may be combined in different ways to form additional embodiments, all of which are within the scope of the present disclosure. It should also be understood that the separation of various system components in the above-described implementations does not require such separation in all implementations, and that the described components and systems may generally be incorporated together in a single product or packaged in multiple products.

[0266] For purposes of this disclosure, certain aspects, advantages, and novel features have been described herein. Not necessarily all such advantages may be achieved in accordance with any particular embodiment. Thus, for example, one skilled in the art will recognize that the present disclosure may be embodied or practiced to achieve one advantage or group of advantages as taught herein, without necessarily achieving other advantages as may be taught or suggested herein.

[0267] Conditional language used herein, such as, among others, "can," "could," "might," "may," "for example," and the like, is intended to generally convey that some embodiments include certain features, elements, and / or steps, while other embodiments do not, unless specifically stated otherwise or understood otherwise within the context in which it is used. Thus, such conditional language is not intended to imply in any way that features, elements, and / or steps are generally required in one or more embodiments, or that one or more embodiments necessarily include logic for determining whether those features, elements, and / or steps are included or performed in any particular embodiment, with or without other input or prompt. The terms "comprising," "including," "having," and the like are synonymous, used inclusively without restriction, and do not exclude additional elements, features, acts, operations, etc. Also, the term "or" is used in its inclusive sense (and not its exclusive sense); when used, for example, to connect a list of elements, the term "or" means one, some, or all of the elements in the list.

[0268] Connecting language such as "at least one of X, Y, and Z," unless specifically stated otherwise, is generally understood in the context in which it is used to convey that an item, term, etc. can be either X, Y, or Z. Thus, such connecting language does not generally imply that some embodiments require the presence of at least one X, at least one Y, and at least one Z.

[0269] As used herein, language of degree, such as the terms "approximately," "about," "nearly, entirely," and "substantially," refers to a value, amount, or characteristic that is close to a stated value, amount, or characteristic and still performs a desired function or achieves a desired result. For example, the terms "approximately," "about," "nearly, entirely," and "substantially" can refer to an amount that is within less than 10%, less than 5%, less than 1%, less than 0.1%, and less than 0.01% of the stated amount. As another example, in some embodiments, the terms "nearly parallel, entirely parallel" and "substantially parallel" refer to a value, amount, or characteristic that deviates from exact parallelism by 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, 0.1 degrees, or less, etc.

[0270] Any methods disclosed herein need not be performed in the order listed. The methods disclosed herein include some actions performed by a practitioner; however, they may also include any third-party command of those actions, either express or implied. For example, an action such as "controlling motor speed" includes "commanding control of motor speed."

[0271] All of the methods and tasks described herein may be performed by a computer system and may be fully automated. The computer system may, in some cases, include multiple separate computers or computing devices (e.g., physical servers, workstations, storage arrays, cloud computing resources, etc.) communicating and cooperating over a network to perform the described functions. Each such computing device typically includes a processor (or multiple processors) that executes program instructions or modules stored in memory or other non-transitory computer-readable storage media or devices (e.g., solid-state storage devices, disk drives, etc.). Various functions disclosed herein may be embodied in such program instructions and / or implemented in the computer system's application-specific circuitry (e.g., ASIC or FPGA). When a computer system includes multiple computing devices, these devices may, but are not necessarily, co-located. The results of the disclosed methods and tasks may be persistently stored by converting physical storage devices, such as solid-state memory chips and / or magnetic disks, to different states. In some embodiments, the computer system may be a cloud-based computer system in which processing resources are shared by multiple separate business entities or other users.

[0272] The scope of the present disclosure is not limited by the specific disclosure of preferred embodiments in this section or elsewhere herein, but may be defined by the claims, as presented in this section or elsewhere herein, or as presented in the future. Claim language is to be interpreted broadly based on the language used in the claims and is not limited to the examples described herein or during prosecution, which examples are to be considered non-exclusive. (Item 1) 1. A respiratory device configured to deliver respiratory therapy to a patient via a patient interface, the respiratory device comprising: controller; a blower including a motor, the motor speed of the blower being controlled by the controller; a pressure sensor configured to measure a pressure of the gas flow downstream of the blower. Includes; The above controller: comparing said pressure to a threshold; In response to the pressure exceeding the threshold, reducing a target motor speed of the blower; and In response to the pressure being less than or equal to the threshold, controlling the motor speed to achieve a target flow rate. 1. A breathing apparatus configured to: (Item 2) Item 14. The respiratory apparatus of item 1, wherein the target motor speed is reduced at a constant rate. (Item 3) Item 14. The respiratory apparatus of item 1, wherein the target motor speed is reduced at a variable rate. (Item 4) 4. The respiratory apparatus of any one of claims 1 to 3, wherein the controller is configured to continuously reduce the target motor speed until the pressure falls below the threshold. (Item 5) 5. The respiratory equipment according to any one of items 1 to 4, wherein the pressure sensor is an absolute pressure sensor. (Item 6) 6. The respiratory apparatus of any one of items 1 to 5, wherein the pressure is measured by taking the difference between the reading of the pressure sensor and the reading of a second pressure sensor, and wherein both the pressure sensor and the second pressure sensor are absolute pressure sensors. (Item 7) 5. The respiratory apparatus of any one of items 1 to 4, wherein the pressure sensor is a gauge pressure sensor configured to take the difference between ambient pressure and the pressure downstream of the blower. (Item 8) 8. The respiratory device of any one of claims 1 to 7, wherein the controller is configured to receive an input of the target flow rate. (Item 9) Item 9. The respiratory device of item 8, wherein the target flow rate is set by a user. (Item 10) 10. The respiratory apparatus of any one of items 1 to 9, comprising an oxygen inlet that is separate from the ambient inlet. (Item 11) Item 11. The respiratory apparatus of item 10, wherein the blower is configured to mix ambient air from the ambient inlet with oxygen from the oxygen inlet. (Item 12) FdO 2 12. The respiratory apparatus of claim 10 or 11, wherein the target flow rate is dependent in part on the target flow rate. (Item 13) The controller further controls the opening of the oxygen inlet valve to control the FdO 2 Item 13. The respiratory apparatus of item 12, configured to control (Item 14) 14. The respiratory device of any one of items 1 to 13, wherein the target flow rate is constant. (Item 15) 15. The respiratory device of any one of claims 1 to 14, wherein the respiratory device is coupled to a bubbler and the controller is configured to detect bubbling by monitoring a change in a flow parameter signal. (Item 16) Item 16. Respiratory apparatus according to item 15, wherein the flow parameter signal comprises a flow signal, a pressure signal, or a combination thereof. (Item 17) 17. A respiratory device according to item 15 or 16, wherein the change is a change in amplitude of the flow parameter signal from a threshold value. (Item 18) 17. Respiratory apparatus according to item 15 or 16, wherein the changes are analysed in the frequency domain. (Item 19) 19. The respiratory apparatus of any one of items 15 to 18, wherein the controller is configured to output a warning in response to a lack of bubbling for a predetermined period of time. (Item 20) 20. The respiratory apparatus of any one of items 15 to 19, wherein the controller is configured to output one or more of the following warnings based on whether foaming is detected: a leak, an obstruction, intermittent foaming, a suggested and / or automatic flow rate change, and / or a flow rate that does not meet the required inspiratory volume. (Item 21) 21. The respiratory apparatus of any one of items 1 to 20, further comprising a humidification chamber. (Item 22) 22. The respiratory apparatus of any one of items 1 to 21, further comprising one or more flow sensors. (Item 23) 23. The respiratory apparatus according to any one of items 1 to 22, wherein the respiratory apparatus is a high-flow respiratory apparatus. (Item 24) 24. The respiratory device according to any one of items 1 to 23, wherein the respiratory device includes a battery. (Item 25) 25. The respiratory device of item 24, wherein the battery is the main power source for the respiratory device. (Item 26) 25. The respiratory device of item 24, wherein the battery is an auxiliary power source for the respiratory device. (Item 27) 27. The respiratory apparatus of any one of items 1 to 26, comprising a motor speed limit. (Item 28) Item 28. The respiratory apparatus of item 27, wherein the motor speed limit is based on ambient pressure. (Item 29) 29. A system comprising the respiratory apparatus of any one of items 1 to 28, further comprising an inhalation conduit for providing the flow of gas to the patient interface. (Item 30) 30. The system of claim 29, wherein the patient interface forms a seal on or around the patient's face. (Item 31) 31. The system of claim 29 or 30, wherein the patient interface is configured for connection to an expiratory conduit. (Item 32) Item 32. The system of item 31, wherein the exhalation conduit is configured to connect to a bubbler. (Item 33) 33. The system of any one of items 29 to 32, which does not include a pressure relief valve between the blower and the patient interface. (Item 34) 1. A respiratory system configured to deliver bubble CPAP therapy to a patient via a patient interface, the respiratory system comprising: 1. A respiratory apparatus comprising: controller; a blower including a motor, the blower motor speed being controlled by the controller, the blower configured to generate a flow of gas to the patient at a target flow rate; and A housing enclosing the controller and the blower breathing equipment, including; an inhalation conduit for providing the flow of gas to the patient interface; an expiratory conduit having a proximal end and a distal end, the proximal end coupled to the patient interface and the distal end submerged at a predetermined depth in a water column; Respiratory system, including: (Item 35) further comprising a pressure sensor configured to measure a pressure of the gas flow downstream of the blower, and the controller: comparing said pressure to a threshold; In response to the pressure exceeding the threshold, reducing a target motor speed of the blower; and In response to the pressure being less than or equal to the threshold, controlling the motor speed to achieve the target flow rate. Item 35. The breathing system of item 34, configured as follows: (Item 36) 36. The respiratory system of claim 35, wherein the target motor speed is reduced at a constant rate. (Item 37) 36. The respiratory system of claim 35, wherein the target motor speed is reduced at a variable rate. (Item 38) 38. A breathing system as described in any one of items 35 to 37, wherein the controller is configured to continuously reduce the target motor speed until the pressure falls below the threshold. (Item 39) 39. The breathing system according to any one of items 35 to 38, wherein the pressure sensor is an absolute pressure sensor. (Item 40) 40. A breathing system according to any one of items 35 to 39, wherein the pressure is measured by taking the difference between the reading of the pressure sensor and the reading of a second pressure sensor, and both the pressure sensor and the second pressure sensor are absolute pressure sensors. (Item 41) 39. A breathing system according to any one of items 35 to 38, wherein the pressure sensor is a gauge pressure sensor configured to take the difference between ambient pressure and the pressure downstream of the blower. (Item 42) 42. A breathing system according to any one of items 34 to 41, wherein the target flow rate is constant. (Item 43) 43. A breathing system as described in any one of items 34 to 42, wherein the controller is configured to receive input of the target flow rate. (Item 44) Item 44. A breathing system as described in item 43, wherein the target flow rate is set by a user. (Item 45) 45. The breathing system of any one of items 34 to 44, comprising an oxygen inlet separate from the ambient air inlet. (Item 46) Item 46. The breathing system of item 45, wherein the blower is configured to mix ambient air from the ambient air inlet with oxygen from the oxygen inlet. (Item 47) FdO 2 47. The breathing system of claim 45 or 46, wherein the target flow rate is dependent in part on the target flow rate. (Item 48) The controller further controls the opening of the oxygen inlet valve to control the FdO 2 Item 48. The breathing system of item 47, configured to control (Item 49) 49. The breathing system according to any one of items 34 to 48, further comprising a bubbler, wherein the water column is contained in the bubbler. (Item 50) Item 50. The respiratory system of item 49, wherein the controller is configured to detect bubbling in the bubbler by monitoring changes in a flow parameter signal. (Item 51) 51. A respiratory system according to item 50, wherein the flow parameter signal comprises a flow signal, a pressure signal, or a combination thereof. (Item 52) 52. A respiratory system according to item 50 or 51, wherein the change is a change in amplitude of the flow parameter signal from a threshold value. (Item 53) 52. The respiratory system according to item 50 or 51, wherein the changes are analyzed in the frequency domain. (Item 54) 54. A breathing system according to any one of items 50 to 53, wherein the controller is configured to output a warning in response to a lack of foaming for a predetermined period of time. (Item 55) 55. A breathing system according to any one of items 50 to 54, wherein the controller is configured to output one or more warnings of: leakage, obstruction, intermittent foaming, suggested and / or automatic flow rate changes, and / or a flow rate that does not meet the required inspiratory volume, based on whether foaming is detected. (Item 56) 56. The respiratory system of any one of items 34 to 55, wherein the patient interface forms a seal on or around the patient's face. (Item 57) 57. The breathing system of any one of items 34 to 56, wherein the breathing apparatus further comprises a humidification chamber. (Item 58) 58. The breathing system of any one of items 34 to 57, wherein the breathing apparatus further comprises one or more flow sensors. (Item 59) 59. The breathing system of any one of items 34 to 58, wherein the breathing system does not include a pressure relief valve between the blower and the patient interface. (Item 60) 60. The breathing system according to any one of items 34 to 59, wherein the breathing apparatus is a high-flow breathing apparatus. (Item 61) 61. The respiratory system of any one of items 34 to 60, wherein the respiratory equipment includes a battery. (Item 62) Item 62. A breathing system according to item 61, wherein the battery is the main power source for the breathing equipment. (Item 63) Item 62. A respiratory system as described in item 61, wherein the battery is an auxiliary power source for the respiratory equipment. (Item 64) 64. The breathing system of any one of items 34 to 63, wherein the breathing equipment includes a motor speed limit. (Item 65) Item 65. The breathing system of item 64, wherein the motor speed limit is based on ambient pressure. (Item 66) 1. A respiratory device configured to deliver respiratory therapy to a patient via a patient interface, the respiratory device comprising: controller; A blower controlled by the above controller; a pressure sensor configured to measure a pressure of the gas flow downstream of the blower. Including, The above controller: comparing said pressure to a threshold; If the pressure exceeds the threshold, controlling the blower to reduce the pressure below the threshold; and If the pressure is below the threshold, controlling the blower to achieve a target flow rate. 1. A breathing apparatus configured to: (Item 67) 1. A breathing system configured to deliver high-flow or bubble CPAP therapy, the breathing system comprising: a respiratory device including a flow generator; a humidifier in fluid communication with the flow generator; a controller for electronically controlling the flow generator; an inhalation conduit in fluid communication with the humidifier; and the respiratory device is switchable between a high-flow therapy mode and a bubble CPAP therapy mode; A breathing system, wherein in the high-flow therapy mode, the breathing device is configured to provide high-flow therapy, and in the bubble CPAP therapy mode, the breathing device is configured to provide bubble CPAP therapy.

Claims

1. 1. A breathing system configured to deliver high-flow or bubble CPAP therapy, the breathing system comprising: a respiratory device including a flow generator; a humidifier in fluid communication with the flow generator; a controller configured to control the flow generator; an inhalation conduit in fluid communication with the humidifier; and the respiratory device is switchable between a high-flow therapy mode and a bubble CPAP therapy mode; In the high-flow therapy mode, the respiratory device is configured to provide high-flow therapy, and in the bubble CPAP therapy mode, the respiratory device is configured to provide bubble CPAP therapy; A user may select the high-flow therapy mode or the bubble CPAP therapy mode via a user interface; the controller is configured to detect bubbling in the pressure regulator; The breathing system is configured such that, in response to the controller detecting the bubbling, it outputs an indication to a user that the bubbling has been detected, or selects or switches to the bubble CPAP therapy mode.

2. 2. The respiratory system of claim 1, wherein the high flow therapy mode is nasal high flow therapy.

3. 3. The respiratory system of claim 1, wherein in the high-flow therapy mode, the system includes a loose-fitting patient interface coupled to the inspiratory conduit.

4. 4. The respiratory system of claim 3, wherein the loose-fitting patient interface is a nasal cannula, and the nasal cannula is configured to be positioned on a user's face to provide gases to the user's nares.

5. 5. The respiratory system of claim 1, wherein in the bubble CPAP therapy mode, the respiratory system includes a tight-fitting patient interface coupled to the inspiratory conduit, an expiratory conduit coupled to the tight-fitting patient interface, and the expiratory conduit coupled to the pressure regulator to regulate pressure within the tight-fitting patient interface and / or the patient's airway.

6. 6. The breathing system of claim 5, wherein the pressure regulator includes a chamber with a column of water, the expiratory conduit is submerged in the column of water, and the pressure delivered to the user is defined or set by the depth to which the expiratory conduit is submerged in the column of water.

7. 7. A breathing system according to any one of claims 1 to 6, wherein the controller automatically switches modes if the controller detects the foaming.

8. 8. The respiratory system of claim 7, wherein the controller is configured to detect the bubbling by monitoring changes in a flow parameter signal, the flow parameter signal comprising a flow signal, a pressure signal, or a combination thereof.

9. 9. The respiratory system of claim 8, wherein the change in the flow parameter signal is a change in amplitude of the flow parameter signal from a threshold value.

10. A respiratory system as described in claim 8 or 9, wherein the changes in the flow parameter signal are analyzed in the frequency domain.

11. A breathing system as described in any one of claims 1 to 10, wherein the breathing equipment includes a housing, and the flow generator and the humidifier are incorporated into the housing.

12. 12. The respiratory system of claim 11, wherein the controller is positioned within the housing.

13. 13. A breathing system according to any one of claims 1 to 12, wherein the humidifier comprises a heating plate and / or a humidification chamber.

14. 14. A breathing system according to claim 13, wherein the heating plate is positioned within the chamber space.

15. 15. A breathing system according to claim 13 or 14, wherein the humidification chamber is removably positioned on the heating plate.

16. 16. A breathing system according to any one of claims 11 to 15, wherein the housing includes a gas outlet, and the inhalation conduit is connectable to the gas outlet.

17. 17. A breathing system according to any one of claims 1 to 16, wherein the inspiratory conduit can be used for the high-flow therapy mode and the bubble CPAP therapy mode.

18. 18. A respiratory system as described in any one of claims 1 to 17, wherein the controller includes a high-flow therapy control program associated with the high-flow therapy mode, and the controller includes a bubble CPAP therapy control program associated with the bubble CPAP therapy mode, and the high-flow therapy control program and / or the bubble CPAP therapy control program define operating parameters.

19. 20. A respiratory system according to claim 18, wherein the controller is configured to select and activate a program corresponding to the selected mode of operation.

20. The operating parameters are: one or more motor speed or pressure limits; one or more alarm conditions; one or more temperature set points; one or more flow limits; 20. The respiratory system of claim 19, comprising at least one of:

21. 21. A breathing system according to any one of claims 18 to 20, wherein the operating parameters include one or more humidity parameters which may define a humidity level.

22. 22. The respiratory system of claim 21, wherein the controller controls the humidifier such that the humidity level provided during the high-flow therapy mode is higher than the humidity level provided during the bubble CPAP therapy mode.

23. A respiratory system as described in any one of claims 1 to 22, wherein a high-flow therapy mode kit for use with the respiratory equipment includes one or more of a non-contact patient interface, the inhalation conduit, and the high-flow therapy mode kit is used in the high-flow therapy mode.

24. A respiratory system as described in any one of claims 1 to 4 or any one of claims 7 to 23 without citing claim 5, wherein a bubble CPAP therapy mode kit for use with the respiratory equipment includes one or more of a close-contact patient interface, the inspiratory conduit, the expiratory conduit, and / or the pressure regulator, and the bubble CPAP therapy mode kit is used in the bubble CPAP therapy mode.

25. A respiratory system as described in claim 5, 6, or any one of claims 7 to 23 which cite claim 5, wherein a bubble CPAP therapy mode kit for use with the respiratory equipment includes one or more of a close-contact patient interface, the inhalation conduit, the exhalation conduit, and / or the pressure regulator, and the bubble CPAP therapy mode kit is used in the bubble CPAP therapy mode.

26. the flow generator is a blower including a motor, the blower motor speed being controlled by the controller; a pressure sensor configured to measure the pressure of the gas flow downstream of the blower; Including; In the bubble CPAP therapy mode, the controller: comparing the pressure to a threshold; In response to the pressure exceeding the threshold, reducing a target motor speed of the blower; and In response to the pressure being less than or equal to the threshold, controlling the motor speed to achieve a target flow rate.

26. A breathing system according to any one of claims 1 to 25, configured so as to

27. The flow generator includes: a blower controlled by said controller; a pressure sensor configured to measure the pressure of the gas flow downstream of the blower; Including, In the bubble CPAP therapy mode, the controller: comparing the pressure to a threshold; If the pressure exceeds the threshold, controlling the blower to reduce the pressure below the threshold; and If the pressure is below the threshold, controlling the blower to achieve a target flow rate.

26. A breathing system according to any one of claims 1 to 25, configured so as to

28. 28. A breathing system according to any one of claims 1 to 27, wherein the flow generator is configured to generate a flow of gas to a patient at a target flow rate in the bubble CPAP therapy mode.

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