WO2024121700A1

WO2024121700A1 - Respiratory therapy system

Info

Publication number: WO2024121700A1
Application number: PCT/IB2023/062167
Authority: WO
Inventors: Stanislav Tatkov; Susyn Joan Rosemarie KELLY
Original assignee: Fisher & Paykel Healthcare Limited
Priority date: 2022-12-05
Filing date: 2023-12-04
Publication date: 2024-06-13

Abstract

A respiratory therapy system (100) for delivering a flow of gases to a patient. The respiratory therapy system (100) has a flow generator (101) configured to generate the flow of gases and a conduit (122) configured to deliver the flow of gases from the flow generator (104) to the patient. The conduit (122) has a lumen and a heater wire configured to heat the flow of gases in the conduit. The respiratory therapy system (100) has a port configured to be in fluid communication with the conduit (122) and for receiving a nebulized substance and introducing it to the flow of gases to the patient. The respiratory therapy system (100) has a controller configured to adjust power delivered to at least the heater wire to regulate an average particle size of the nebulized substance to or towards a target.

Description

Respiratory Therapy System

FIELD OF THE INVENTION

[0001] The present disclosure generally relates to a respiratory therapy system for delivering a flow of gases to a patient. More particularly, the present disclosure relates to a respiratory therapy system which regulates the average particle size of a nebulized substance introduced into the system.

BACKGROUND TO THE INVENTION

[0002] Respiratory therapy apparatus or systems for delivering a flow of gases can be used to improve ventilation of a patient. Such apparatus or systems can be used to improve patient comfort and/or improve the prognosis of the patient's respiratory illness.

[0003] In some systems, the respiratory therapy system may be configured to receive nebulized substances e.g., from a nebulizer. For example, a nebulizer may be used to deliver medicinal substance to an airway of a patient along with the delivery of respiratory gases to the airway of the patient. In some cases, the respiratory therapy system receives the nebulized substance which is then carried by a flow of gases through a breathing conduit, and out into the patient's airway via a patient interface.

[0004] However, the efficiency of the nebulized substance delivery may not be as desired, for example when the nebulized substance sticks to, settles along or becomes caught on an internal wall of the conduit and does not progress to the patient's airway, or an adequate amount of the substance does not progress as far into the patient's airway as desired.

[0005] It is therefore an object of the present invention to provide a respiratory therapy apparatus or system which overcomes or at least partially ameliorates some of the abovementioned disadvantages or which at least provides the public with a useful choice.

SUMMARY OF INVENTION

[0006] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a respiratory therapy system for delivering a flow of gases to a patient is disclosed, the respiratory therapy system for delivering a flow of gases to a patient, comprising: a flow generator configured to deliver the flow of gases to the patient; a conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit; a port configured to be in fluid communication with the conduit for receiving a nebulized substance and introducing it to the flow of gases to the patient; and a controller configured to at least adjust power delivered to the heater wire to regulate average particle size of the nebulized substance to a target.

[0007] In some configurations, the power delivered to the heater wire to reach a target relative humidity.

[0008] In some configurations, the controller continually controls the power delivered to the heater wire to maintain a target relative humidity.

[0009] In some configurations, the target relative humidity is the relative humidity of the flow gases in the conduit.

[00010] In some configurations, the target relative humidity is the relative humidity of the flow gases at a patient end of the conduit.

[00011] In some configurations, the target relative humidity is approximately 80%.

[00012] In some configurations, the target relative humidity is less than 80%.

[00013] In some configurations, the target relative humidity is approximately 60%.

[00014] In some configurations, the target relative humidity is less than 60%. [00015] In some configurations, the target average particle size is based on a desired distance of travel into the patient's respiratory tract.

[00016] In some configurations, the desired distance of travel is for dispersion in or around the patient's upper respiratory tract.

[00017] In some configurations, the desired distance of travel is for dispersion beyond the patient's upper respiratory tract.

[00018] In some configurations, the desired distance of travel is for dispersion in or around the patient's lower respiratory tract.

[00019] In some configurations, the target average particle size is relatively larger when the desired distance of travel is dispersion in or around the patient's upper respiratory tract than the target average particle size when the desired distance of travel is dispersion in or around the patient's lower respiratory tract.

[00020] In some configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of <1.0 pm.

[00021] In some configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.5 pm and < 1.0 pm.

[00022] In some configurations, the target average particle size is a median aerodynamic diameter (MMAD) of <0.5 pm.

[00023] In some configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.1 pm and 0.5 pm.

[00024] In some configurations, the respiratory therapy system further comprises a humidifier, the humidifier comprising a heating element. [00025] In some configurations, the controller is configured to adjust power delivered to the heating element to regulate average particle size of the nebulized substance to a target.

[00026] In some configurations, the controller controls both the power delivered to the heater wire and the power delivered to the heating element to achieve target average particle size.

[00027] In some configurations, the controller controls the power delivered to the heater wire independently from the power delivered to the heating element to regulate average particle size.

[00028] In some configurations, the heating element is a heating plate.

[00029] In some configurations, the port for the nebulizer is located downstream from the flow generator.

[00030] In some configurations, the port for the nebulizer is located at the humidifier.

[00031] In some configurations, the port for the nebulizer is located at or towards an inlet or outlet of the humidifier.

[00032] In some configurations, the port for the nebulizer is located at or towards an outlet of the humidifier.

[00033] In some configurations, the port for the nebulizer is located upstream from a device end of the conduit.

[00034] In some configurations, the port for the nebulizer is located at or towards a device end of the conduit.

[00035] In some configurations, the port is configured to receive the nebulizer indirectly. [00036] In some configurations, the respiratory therapy system further comprises a connector configured to be connected to the port at one opening, and for receiving the nebulizer at another opening.

[00037] In some configurations, the respiratory therapy system further comprises a nebulizer configured to be connected at the port, the nebulizer introducing the nebulized substance to the flow of gases.

[00038] In some configurations, the system comprises a standard therapy mode and a nebulisation therapy mode.

[00039] In some configurations, the nebulisation therapy mode comprises a target relative humidity lower than a target relative humidity in the standard therapy mode.

[00040] In some configurations, the power delivered to the heater wire in the nebulisation therapy mode is higher than the power delivered in the standard therapy mode.

[00041] In some configurations, the standard therapy mode comprises a target relative humidity of approximately 100% and the nebulisation therapy mode comprises a target relative humidity less than 100%.

[00042] In some configurations, the target relative humidity in the nebulisation therapy mode is less than 80%.

[00043] In some configurations, the target relative humidity in the nebulisation therapy mode is less than 60%.

[00044] In some configurations, a user can manually adjust between the standard therapy mode and the nebulisation therapy mode.

[00045] In some configurations, a feature for manually adjusting target average particle size becomes available after entering nebulisation therapy mode. [00046] In some configurations, the system is configured to automatically control power to the heater wire to achieve a default target average particle size.

[00047] In some configurations, the system is configured to automatically control power to the heating element to achieve a default target average particle size.

[00048] In some configurations, the default target average particle size is <1.0 pm.

[00049] In some configurations, the respiratory therapy system further comprises a user control interface.

[00050] In some configurations, the user control interface comprises a user control interface element for adjusting the target average particle size.

[00051] In some configurations, the user control interface comprises a user control interface element for adjusting a target distance of travel into the patient's respiratory tract.

[00052] In some configurations, the user control interface comprises a user control interface element for selecting a standard therapy mode and a nebulisation therapy mode.

[00053] In some configurations, the user control interface comprises a touch screen interface.

[00054] In some configurations, the user control interface comprises mechanical interface having a physical element being one or a combination of a slider, dial, buttons.

[00055] In some configurations, the conduit comprises a length of greater than 0.5 meter.

[00056] In some configurations, the conduit comprises a length of greater than 1 meter.

[00057] In some configurations, the conduit comprises a length of greater than 1.5 meter. [00058] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a method for delivering a flow of gases to a patient is disclosed, the method for delivering a flow of gases to a patient comprising: providing a respiratory therapy apparatus comprising: a flow generator configured to deliver the flow of gases to the patient; a conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit; introducing a nebulized substance into the flow of gases to the patient; and adjusting power delivered to the heater wire to regulate average particle size of the nebulized substance to a target.

[00059] In some configurations, the method further comprises adjusting the power delivered to the heater wire to reach a target relative humidity.

[00060] In some configurations, the method further comprises continually controlling the power delivered to the heater wire to maintain a target relative humidity.

[00061] In some configurations, the target relative humidity is the relative humidity of the flow gases in the conduit.

[00062] In some configurations, the target relative humidity is the relative humidity of the flow gases at a patient end of the conduit.

[00063] In some configurations, the target relative humidity is approximately 80%.

[00064] In some configurations, the target relative humidity is less than 80%.

[00065] In some configurations, the target relative humidity is approximately 60%.

[00066] In some configurations, the target relative humidity is less than 60%. [00067] In some configurations, the target average particle size is based on a desired distance of travel into the patient's respiratory tract.

[00068] In some configurations, the desired distance of travel is for dispersion in or around the patient's upper respiratory tract.

[00069] In some configurations, the desired distance of travel is for dispersion beyond the patient's upper respiratory tract.

[00070] In some configurations, the desired distance of travel is for dispersion in or around the patient's lower respiratory tract.

[00071] In some configurations, the target average particle size is smaller when the desired distance of travel is dispersion in or around the patient's upper respiratory tract than the target average particle size when the desired distance of travel is dispersion in or around the patient's lower respiratory tract.

[00072] In some configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of <1.0 pm.

[00073] In some configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.5 pm and 1.0 pm.

[00074] In some configurations, the target average particle size is a median aerodynamic diameter (MMAD) of <0.5 pm.

[00075] In some configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.1 pm and 0.5 pm.

[00076] In some configurations, the method further comprises providing a humidifier, the humidifier comprising a heating element. [00077] In some configurations, the method further comprises to adjusting power delivered to the heating element to regulate average particle size of the nebulized substance to a target.

[00078] In some configurations, the method further comprises controlling both the power delivered to the heater wire and the power delivered to the heating element to achieve target average particle size.

[00079] In some configurations, the method further comprises controlling the power delivered to the heater wire independently from the power delivered to the heating element to regulate average particle size.

[00080] In some configurations, the method further comprises connecting a nebulizer at the port, the nebulizer introducing the nebulized substance to the flow of gases.

[00081] In some configurations, the method further comprises connecting a nebulizer indirectly to the port via a mount/ connector.

[00082] In some configurations, the system comprises a standard therapy mode and a nebulisation therapy mode.

[00083] In some configurations, the method further comprises adjusting the power to heater wire such that the nebulisation therapy mode reaches a target relative humidity lower than a target relative humidity in the standard therapy mode.

[00084] In some configurations, the method further comprises delivering higher power to the heater wire in the nebulisation therapy mode than the power delivered in the standard therapy mode.

[00085] In some configurations, the method further comprises adjusting power to the heater wire to reach wherein the standard therapy mode comprises a target relative humidity of approximately 100% and the nebulisation therapy mode comprises a target relative humidity less than 100%.

[00086] In some configurations, the method further comprises manually adjusting between the standard therapy mode and the nebulisation therapy mode.

[00087] In some configurations, the method further comprises automatically controlling power to the heater wire to achieve a default target average particle size.

[00088] In some configurations, the method further comprises automatically controlling power to the heating element to achieve a default target average particle size.

[00089] In some configurations, the method further comprises adjusting the target average particle size.

[00090] In some configurations, the method further comprises adjusting a target distance of travel of the nebulized substance into the patient's respiratory tract.

[00091] In some configurations, the method further comprises selecting a standard therapy mode and a nebulisation therapy mode on a user control interface element.

[00092] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a respiratory therapy system for delivering a flow of gases to a patient is disclosed, the respiratory therapy system for delivering a flow of gases to a patient, comprising: a flow generator configured to deliver the flow of gases to the patient; a humidifier comprising a heating element; a port configured to be in fluid communication with the conduit for receiving a nebulized substance and introducing it to the flow of gases to the patient; and a controller configured to at least adjust power delivered to the heating element to regulate average particle size of the nebulized substance to a target. [00093] In some configurations, the respiratory therapy system further comprises a conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit.

[00094] In some configurations, the controller is configured to adjust power delivered to the heater wire to regulate average particle size of the nebulized substance to a target.

[00095] In some configurations, the controller controls both the power delivered to the heater wire and the power delivered to the heating element to achieve target average particle size.

[00096] In some configurations, the controller controls the power delivered to the heater wire independently from the power delivered to the heating element to regulate average particle size.

[00097] In some configurations, the controller controls the power delivered to the heating element and/or the heater wire to reach a target relative humidity.

[00098] In some configurations, the controller continually controls the power delivered to the heating element and/or the heater wire to maintain the target relative humidity.

[00099] In some configurations, the target relative humidity is the relative humidity of the flow gases in the conduit.

[000100] In some configurations, the target relative humidity is the relative humidity of the flow gases at a patient end of the conduit.

[000101] In some configurations, the target relative humidity is approximately 80%.

[000102] In some configurations, the target relative humidity is less than 80%.

[000103] In some configurations, the target relative humidity is approximately 60%. [000104] In some configurations, the target relative humidity is less than 60%.

[000105] In some configurations, the target average particle size is based on a desired distance of travel into the patient's respiratory tract.

[000106] In some configurations, the desired distance of travel is for dispersion in or around the patient's upper respiratory tract.

[000107] In some configurations, the desired distance of travel is for dispersion beyond the patient's upper respiratory tract.

[000108] In some configurations, the desired distance of travel is for dispersion in or around the patient's lower respiratory tract.

[000109] In some configurations, the target average particle size is smaller when the desired distance of travel is dispersion in or around the patient's upper respiratory tract than the target average particle size when the desired distance of travel is dispersion in or around the patient's lower respiratory tract.

[000110] In some configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of <1.0 pm.

[000111] In some configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.5 pm and 1.0 pm.

[000112] In some configurations, the target average particle size is a median aerodynamic diameter (MMAD) of <0.5 pm.

[000113] In some configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.1 pm and 0.5 pm. [000114] In some configurations, the heating element is a heating plate.

[000115] In some configurations, the port for the nebulizer is located downstream from the flow generator.

[000116] In some configurations, the port for the nebulizer is located at the humidifier.

[000117] In some configurations, the port for the nebulizer is located at or towards an inlet or outlet of the humidifier.

[000118] In some configurations, the port for the nebulizer is located at or towards an outlet of the humidifier.

[000119] In some configurations, the port for the nebulizer is located upstream from a device end of the conduit.

[000120] In some configurations, the port for the nebulizer is located at or towards a device end of the conduit.

[000121] In some configurations, the port is configured to receive the nebulizer indirectly.

[000122] In some configurations, the respiratory therapy system further comprises a mount/ connector configured to be connected to the port at one opening, and for receiving the nebulizer at another opening.

[000123] In some configurations, the respiratory therapy system further comprises a nebulizer configured to be connected at the port, the nebulizer introducing the nebulized substance to the flow of gases.

[000124] In some configurations, the system comprises a standard therapy mode and a nebulisation therapy mode. [000125] In some configurations, the nebulisation therapy mode comprises a target relative humidity lower than a target relative humidity in the standard therapy mode.

[000126] In some configurations, the power delivered to the heater wire in the nebulisation therapy mode is higher than the power delivered in the standard therapy mode.

[000127] In some configurations, the standard therapy mode comprises a target relative humidity of approximately 100% and the nebulisation therapy mode comprises a target relative humidity less than 100%.

[000128] In some configurations, the target relative humidity in the nebulisation therapy mode is less than 80%.

[000129] In some configurations, the target relative humidity in the nebulisation therapy mode is less than 60%.

[000130] In some configurations, a user can manually adjust between the standard therapy mode and the nebulisation therapy mode.

[000131] In some configurations, a feature for manually adjusting target average particle size becomes available after entering nebulisation therapy mode.

[000132] In some configurations, the system is configured to automatically control power to the heater wire to achieve a default target average particle size.

[000133] In some configurations, the system is configured to automatically control power to the heating element to achieve a default target average particle size.

[000134] In some configurations, the default target average particle size is <1.0 pm.

[000135] In some configurations, the respiratory therapy system further comprises a user control interface. [000136] In some configurations, the user control interface comprises a user control interface element for adjusting the target average particle size.

[000137] In some configurations, the user control interface comprises a user control interface element for adjusting a target distance of travel into the patient's respiratory tract.

[000138] In some configurations, the user control interface comprises a user control interface element for selecting a standard therapy mode and a nebulisation therapy mode.

[000139] In some configurations, the user control interface comprises a touch screen interface.

[000140] In some configurations, the user control interface comprises mechanical interface having a physical element being one or a combination of a slider, dial, buttons.

[000141] In some configurations, the conduit comprises a length of greater than 0.5 meter.

[000142] In some configurations, the conduit comprises a length of greater than 1 meter.

[000143] In some configurations, the conduit comprises a length of greater than 1.5 meter.

[000144] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a method for delivering a flow of gases to a patient is disclosed, the method for delivering a flow of gases to a patient comprising: providing a respiratory therapy apparatus comprising: a flow generator configured to deliver the flow of gases to the patient; a humidifier comprising a heating element; introducing a nebulized substance into the flow of gases to the patient; and adjusting power delivered to the heating element to regulate average particle size of the nebulized substance to a target. In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a respiratory therapy system for delivering a flow of gases to a patient is disclosed, the respiratory therapy system for delivering a flow of gases to a patient, comprising: a flow generator configured to deliver the flow of gases to the patient; a port configured to be in fluid communication with the conduit for receiving a nebulized substance and introducing it to the flow of gases to the patient; and a controller for adjusting power delivered to a component in the system to regulate average particle size of the nebulized substance to a target; wherein the system comprises a standard therapy mode and a nebulisation therapy mode; and wherein the nebulisation therapy mode comprises a target relative humidity lower than a target relative humidity in the standard therapy mode.

[000145] In some configurations, the respiratory therapy system further comprises increasing temperature of the flow of gases relative to a dew point such that the relative humidity decreases in the nebulisation therapy mode.

[000146] In some configurations, the respiratory therapy system further comprises a conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit.

[000147] In some configurations, the controller is configured to adjust power delivered to the heater wire to regulate average particle size of the nebulized substance to a target.

[000148] In some configurations, the respiratory therapy system further comprises a humidifier, the humidifier comprising a heating element.

[000149] In some configurations, the controller is configured to adjust power delivered to the heating element to regulate average particle size of the nebulized substance to a target. [000150] In some configurations, the controller controls both the power delivered to the heater wire and the power delivered to the heating element to achieve target average particle size.

[000151] In some configurations, the heating element is a heating plate.

[000152] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a respiratory therapy system for delivering a flow of gases to a patient is disclosed, the respiratory therapy system for delivering a flow of gases to a patient, comprising: a flow generator configured to deliver the flow of gases to the patient; a port configured to be in fluid communication with the conduit for receiving a nebulized substance and introducing it to the flow of gases to the patient; and a controller for adjusting power delivered to a component in the system to regulate average particle size of the nebulized substance to a target; wherein the target average particle size is a mass median aerodynamic diameter (MMAD) of <1.0 pm.

[000153] In some configurations, the target average particle size is based on a desired distance of travel into the patient's respiratory tract.

[000154] In some configurations, the desired distance of travel is for dispersion beyond the patient's upper respiratory tract.

[000155] In some configurations, the desired distance of travel is for dispersion in or around the patient's lower respiratory tract.

[000156] In some configurations, the respiratory therapy system further comprises increasing temperature of the flow of gases relative to a dew point such that the relative humidity decreases to achieve a target average particle size. [000157] In some configurations, the respiratory therapy system further comprises a conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit.

[000158] In some configurations, the controller is configured to adjust power delivered to the heater wire to regulate average particle size of the nebulized substance to a target.

[000159] In some configurations, the respiratory therapy system further comprises a humidifier, the humidifier comprising a heating element.

[000160] In some configurations, the controller is configured to adjust power delivered to the heating element to regulate average particle size of the nebulized substance to a target.

[000161] In some configurations, the controller controls both the power delivered to the heater wire and the power delivered to the heating element to achieve target average particle size.

[000162] In some configurations, the heating element is a heating plate.

[000163] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein, a respiratory therapy system for delivering a flow of gases to a patient is disclosed, the respiratory therapy system for delivering a flow of gases to a patient, comprising: a flow generator configured to deliver the flow of gases to the patient; a conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit; a nebulizer in fluid communication with the conduit for introducing a nebulized to the flow of gases to the patient; and a controller configured to adjust power delivered to a component in the system to regulate average particle size of the nebulized substance to a target. [000164] In some configurations, the target average particle size is based on a desired distance of travel into the patient's respiratory tract.

[000165] In some configurations, the desired distance of travel is for dispersion beyond the patient's upper respiratory tract.

[000166] In some configurations, the desired distance of travel is for dispersion in or around the patient's lower respiratory tract.

[000167] In some configurations, the respiratory therapy system further comprises increasing temperature of the flow of gases relative to a dew point such that the relative humidity decreases to achieve a target average particle size.

[000168] In some configurations, the respiratory therapy system further comprises a conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit.

[000169] In some configurations, the controller is configured to adjust power delivered to the heater wire to regulate average particle size of the nebulized substance to a target.

[000170] In some configurations, the respiratory therapy system further comprises a humidifier, the humidifier comprising a heating element.

[000171] In some configurations, the controller is configured to adjust power delivered to the heating element to regulate average particle size of the nebulized substance to a target.

[000172] In some configurations, the controller controls both the power delivered to the heater wire and the power delivered to the heating element to achieve target average particle size.

[000173] In some configurations, the heating element is a heating plate. [000174] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein but not claimed, a method for delivering a flow of gases to a patient is disclosed, the method for delivering a flow of gases to a patient comprising: providing a respiratory therapy apparatus comprising: a flow generator configured to generate the flow of gases; a conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit; introducing a nebulized substance into the flow of gases to the patient; and adjusting power delivered to the heater wire to regulate the average particle size of the nebulized substance to a target.

[000175] In some configurations, the method further comprises adjusting the power delivered to the heater wire to reach a target relative humidity of flow of gases.

[000176] In some configurations, the method further comprises continually controlling the power delivered to the heater wire to maintain a target relative humidity of flow of gases.

[000177] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein but not claimed, a respiratory therapy system for delivering a flow of gases to a patient is disclosed, the respiratory therapy system for delivering a flow of gases to a patient comprising: a flow generator configured to generate the flow of gases; a humidifier comprising a heating element; a port configured to be in fluid communication with a conduit and, the port configured to receive a nebulized substance and introduce the nebulized substance to the flow of gases to the patient; and a controller configured to adjust power delivered to at least the heating element to regulate an average particle size of the nebulized substance to or towards a target. [000178] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein but not claimed, a method for delivering a flow of gases to a patient, the method for delivering a flow of gases to a patient comprising: providing a respiratory therapy apparatus comprising: a flow generator configured to generate the flow of gases; a humidifier comprising a heating element; introducing a nebulized substance into the flow of gases to the patient; and adjusting power delivered to the heating element to regulate an average particle size of the nebulized substance to or towards a target.

[000179] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein but not claimed, a respiratory therapy system for delivering a flow of gases to a patient is disclosed, the respiratory therapy system for delivering a flow of gases to a patient comprising: a flow generator configured to generate the flow of gases; a port configured to be in fluid communication with for receiving a nebulized substance and introducing it to the flow of gases to the patient; and a controller for adjusting power delivered to a component in the system to regulate average particle size of the nebulized substance to or towards a target; wherein the system comprises a standard therapy mode and a nebulisation therapy mode; and wherein the nebulisation therapy mode comprises a relative humidity lower than a relative humidity in the standard therapy mode.

[000180] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein but not claimed, a respiratory therapy system for delivering a flow of gases to a patient is disclosed, the respiratory therapy system for delivering a flow of gases to a patient comprising: a flow generator configured to generate the flow of gases; a port configured to be in fluid communication or receiving a nebulized substance and introducing it to the flow of gases to the patient; and a controller for adjusting power delivered to a component in the system to regulate average particle size of the nebulized substance to or towards a target; wherein the target average particle size is a mass median aerodynamic diameter (MMAD) of <1.0 micrometer.

[000181] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein but not claimed, a respiratory therapy system for delivering a flow of gases to a patient, the respiratory therapy system for delivering a flow of gases to a patient comprising: a flow generator configured to generate the flow of gases; a conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit; a nebulizer in fluid communication with the conduit for introducing a nebulized to the flow of gases to the patient; and a controller configured to adjust power delivered to a component in the system to regulate average particle size of the nebulized substance to a target.

[000182] In accordance with certain features, aspects and advantages of at least one of the embodiments disclosed herein but not claimed, a respiratory therapy apparatus for delivering a flow of gases to a patient, the respiratory therapy apparatus for delivering a flow of gases to a patient comprising: a flow generator configured to generate the flow of gases; a humidifier comprising a heating element; a port configured to be in fluid communication with a conduit, the port configured to receive a nebulized substance and introduce the nebulized substance to the flow of gases to the patient; and a controller configured to adjust power delivered to at least the heating element to regulate an average particle size of the nebulized substance to or towards a target.

[000183] In some configurations, the apparatus configured to fluidly connect to a conduit, the conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit.

[000184] In some configurations, the controller is configured to adjust power delivered to a heater wire to regulate average particle size of the nebulized substance to a target.

[000185] In some configurations, the port for the nebulizer is located upstream from an apparatus end of the conduit.

[000186] In some configurations, the port for the nebulizer is located at or towards an apparatus end of the conduit.

[000187] In some configurations, the respiratory therapy apparatus further comprises a mount/ connector configured to be connected to the port at one opening, and for receiving the nebulizer at another opening.

[000188] In some configurations, the port is configured to be connected to a nebulizer, the nebulizer introducing the nebulized substance to the flow of gases.

[000189] In some configurations, the apparatus comprises a standard therapy mode and a nebulisation therapy mode.

[000190] In some configurations, the apparatus is configured to automatically control power to the heater wire to achieve a default target average particle size.

[000191] In some configurations, the apparatus is configured to automatically control power to the heating element to achieve a default target average particle size.

[000192] In some configurations, the respiratory therapy apparatus further comprises a user control interface. [000193] The term "comprising" as used in this specification means "consisting at least in part of". When interpreting each statement in this specification that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner.

[000194] This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

[000195] The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

[000196] It should be understood that alternative embodiments may comprise any or all combinations of two or more of the parts, elements or features or configurations as illustrated, described or referred to in this specification.

BRIEF DESCRIPTION OF DRAWINGS

[000197] Specific embodiments and modifications thereof will become apparent to those skilled in the art from the detailed description herein having reference to the figures that follow, of which:

[000198] Figure 1 shows a schematic diagram of a respiratory therapy system.

[000199] Figure 2 shows another schematic diagram of a respiratory therapy system.

[000200] Figure 3 shows a circuit sensing board that can be used in the respiratory therapy system.

[000201] Figure 4 shows a schematic diagram of a respiratory therapy system receiving a nebulised substance from a nebuliser. [000202] Figure 5 shows a perspective of a respiratory therapy apparatus for use in a respiratory therapy system configured in accordance with certain features, aspects and advantages of some configurations described.

[000203] Figure 6 shows a perspective view of a breathing apparatus of the respiratory therapy system.

[000204] Figure 7 shows a flow diagram of a method of use and control of the respiratory therapy system.

[000205] Figure 8A shows a graph of test results showing the correlation between relative humidity, air temperature, and the MMAD of the nebulized substances in a respiratory therapy system at a flow rate of 20 L/min.

[000206] Figure 8B shows a graph of test results showing the correlation between relative humidity, air temperature, and the MMAD of the nebulized substances in a respiratory therapy system at a flow rate of 40 L/min.

DETAILED DESCRIPTION

[000207] Although certain examples are described below, those of skill in the art will appreciate that the disclosure extends beyond the specifically disclosed examples and/or uses and obvious modifications and equivalents thereof. Thus, it is intended that the scope of the disclosure herein disclosed should not be limited by any particular examples described below.

1. General Description of Respiratory therapy system

[000208] With reference to Figure 1, an exemplary configuration of a respiratory therapy system 100 is shown. The respiratory therapy system 100 delivers a flow of gases to a patient.

[000209] In the preferred configurations, the respiratory therapy system 100 comprises a flow generator 101 for generating a flow of gases to be delivered to a patient. The illustrated flow generator 101 comprises a gas inlet 102 and a gas outlet 104.

[000210] In some configurations, the flow generator 101 may also comprise a blower 106. The blower 106 can draw in gas from the gas inlet 102. In some configurations, the flow generator 101 can comprise a source or container of compressed gas (e.g., air, oxygen, etc.). The container can comprise a valve that can be adjusted to control the flow of gas leaving the container. In some configurations, the flow generator 101 can use such a source of compressed gas and/or another gas source in lieu of the blower 106. In some configurations, the blower 106 can be used in conjunction with another gas source. In some configurations, the blower 106 can comprise a motorized blower or can comprise a bellows arrangement or some other structure capable of generating a gas flow. The blower 106 can operate at a motor speed of greater than about 1,000 RPM and less than about 8,000 RPM, greater than about 2,000 RPM and less than about 10,000 RPM, or between any of the foregoing values. The blower 106 can mix the gases entering the blower 106 through the inlet ports (for example, the ambient air inlet port 102 and/or an oxygen inlet port). Using the blower 106 as the mixer can decrease the pressure drop relative to systems with separate mixers, such as static mixers comprising baffles.

[000211] In some configurations, the flow generator 101 draws in atmospheric gases through the gas inlet 102. In some configurations, the flow generator 101 is adapted both to draw in atmospheric gases through the gas inlet 102 and to accept other gases (e.g., oxygen, nitric oxide, carbon dioxide, etc.) through the same gas inlet 102 or a different gas inlet. For example, the gas inlet 102 may be a supplemental oxygen inlet. The supplemental oxygen inlet may include a valve (for example, a solenoid proportional valve, binary valve, or other suitable valve type) that can control a flow of oxygen into the flow generator 101. The valve may be in electrical communication with a controller 113 of the respiratory therapy system 100. Other configurations also are possible.

[000212] In some configurations, the flow generator 101 is controlled to provide high flow therapy. In some configurations, the flow generator 101 is controlled to provide continuous positive airway pressure (CPAP) therapy. In some configurations, the flow generator 101 is a dual therapy device, controlled to provide both high flow and/or CPAP therapy. In some configurations, the flow generator 101 is controlled to provide one or more of the following: bi-level pressure therapy, CPAP therapy or high flow therapy.

[000213] The respiratory therapy system 100 in some configurations measures and controls the oxygen content of the gas being delivered to the patient, and therefore the oxygen content of the gas inspired by the patient. Oxygen may be measured by placing one or more gas composition sensors (such as an ultrasonic transducer system) after the oxygen and ambient air have been mixed. The measurement can be taken within the respiratory therapy apparatus 100, the conduit 122, the patient interface 124, or at any other suitable location.

[000214] The oxygen concentration measured in the apparatus may be equivalent to the fraction of delivered oxygen (FdO2) and may be substantially the same as the oxygen concentration the patient is breathing, the fraction of inspired oxygen (FiO2), and as such the terms may be seen as equivalent.

[000215] Oxygen concentration may also be measured by using flow rate sensors on at least two of the ambient air inlet conduit, the oxygen inlet conduit, and the patient breathing conduit to determine the flow rate of at least two gases. By determining the flow rate of both inlet gases or one inlet gas and one total flow rate, along with the assumed or measured oxygen concentrations of the inlet gases (about 20.9% for ambient air, about 100% for oxygen), the oxygen concentration of the final gas composition can be calculated. Alternatively, flow rate sensors can be placed at all three of the ambient air inlet conduit, the oxygen inlet conduit, and the breathing conduit to allow for redundancy and testing that each sensor is working correctly by checking for consistency of readings. Other methods of measuring the oxygen concentration delivered by the respiratory therapy system 100 can also be used.

[000216] The respiratory therapy system 100 may provide high flow therapy, in which the high flow rate of gas delivered meets or exceeds the peak inspiratory demand of the patient.

[000217] High flow therapy as discussed herein is intended to be given its typical ordinary meaning as understood by a person of skill in the art which generally refers to a breathing assistance apparatus delivering a targeted flow of humidified respiratory gases via an intentionally unsealed patient interface with flow rates generally intended to meet or exceed inspiratory flow of a patient. Typical patient interfaces include, but are not limited to, a nasal or tracheal patient interface. Typical flow rates for adults often range from, but are not limited to, about fifteen litres per minute to about sixty litres per minute or greater. Typical flow rates for paediatric patients (such as neonates, infants and children) often range from, but are not limited to, about one litre per minute per kilogram of patient weight to about three litres per minute per kilogram of patient weight or greater. High flow therapy can also optionally include gas mixture compositions including supplemental oxygen and/or administration of therapeutic medicaments. 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.

[000218] For example, in some configurations, for an adult patient 'high flow therapy' may refer to the delivery of gases to a patient at a flow rate of greater than or equal to about 10 litres per minute (10 LPM), such as between about 10 LPM and about 100 LPM, or between about 15 LPM and about 95 LPM, or between about 20 LPM and about 90 LPM, or between about 25 LPM and about 85 LPM, or between about 30 LPM and about 80 LPM, or between about 35 LPM and about 75 LPM, or between about 40 LPM and about 70 LPM, or between about 45 LPM and about 65 LPM, or between about 50 LPM and about 60 LPM. In some configurations, for a neonatal, infant, or child patient, 'high flow therapy' may refer to the delivery of gases to a patient at a flow rate of greater than 1 LPM, such as between about 1 LPM and about 25 LPM, or between about 2 LPM and about 25 LPM, or between about 2 LPM and about 5 LPM, or between about 5 LPM and about 25 LPM, or between about 5 LPM and about 10 LPM, or between about 10 LPM and about 25 LPM, or between about 10 LPM and about 20 LPM, or between about 10 LPM and 15 LPM, or between about 20 LPM and 25 LPM. A high flow therapy apparatus with an adult patient, a neonatal, infant, or child patient, may, in some configurations, deliver gases to the patient at a flow rate of between about 1 LPM and about 100 LPM, or at a flow rate in any of the sub-ranges outlined above. Gases delivered may comprise a percentage of oxygen. In some configurations, the percentage of oxygen in the gases delivered may be between about 20% and about 100%, or between about 30% and about 100%, or between about 40% and about 100%, or between about 50% and about 100%, or between about 60% and about 100%, or between about 70% and about 100%, or between about 80% and about 100%, or between about 90% and about 100%, or about 100%, or 100%.

[000219] High flow therapy may be effective in meeting or exceeding the patient's inspiratory flow, increasing oxygenation of the patient, and/or reducing the work of breathing.

[000220] High flow therapy may be administered to the nares of a patient and/or orally, or via a tracheostomy interface. [000221] High flow therapy may generate a flushing effect in the nasopharynx such that the anatomical dead space of the upper airways is flushed by the high incoming gases flow. This can create a reservoir of fresh gas available for each and every breath, while reducing rebreathing of nitrogen and carbon dioxide. Meeting inspiratory demand and flushing the airways is additionally important when trying to control the patient's FdO2. High flow therapy can be delivered with a non-sealing patient interface such as, for example, a nasal cannula. High flow therapy may slow down respiratory rate of the patient. High flow therapy may provide expiratory resistance to a patient.

[000222] High flow therapy may be used to treat patients with obstructive pulmonary conditions e.g. COPD, bronchiectasis, dyspnea, cystic fibrosis, emphysema and/or patients with respiratory distress or hypercapnic patients.

[000223] The term "non-sealing patient interface" (i.e. unsealed patient interface) as used herein can refer to an interface providing a pneumatic link between an airway of a patient and a gases flow source (such as from flow generator 101 ) that does not completely occlude the airway of the patient. A non-sealed pneumatic link can comprise an occlusion of less than about 95% of the airway of the patient. The non-sealed pneumatic link can comprise an occlusion of less than about 90% of the airway of the patient. The non-sealed pneumatic link can comprise an occlusion of between about 40% and about 80% of the airway of the patient. The airway can include one or both nares of the patient and/or their mouth. For a nasal cannula the airway is through the nares.

[000224] In some configurations, the respiratory therapy system 100 further comprises a conduit 122. The conduit 122 is configured to deliver the flow of gases from the flow generator 101 to the patient. In the preferred configurations the conduit 122 is a patient breathing tube.

[000225] The conduit 122 comprises a lumen and can comprise one or more heater wires 123 configured to heat the flow of gases in the conduit. The conduit 122 comprising a heater wire 123 can be used to add heat to gases passing through the conduit. The heat can reduce or eliminate the likelihood of condensation of water entrained in the gas stream along a wall of the conduit 122. The conduit heater can comprise one or more resistive wires located in, on, around or near a wall of the conduit 122. In one or more configuration, such one or more resistive wires can be located outside of any gas passage. In one or more configurations, such one or more resistive wires are not in direct contact with the gases passing through the conduit 122. In one or more configurations, a wall or surface of the conduit 122 intercedes between the one or more resistive wires and the gases passing through the conduit 122. In the preferred configurations the conduit 122 is a heated breathing tube.

[000226] With reference to figure 6 showing an example breathing therapy system 100, the system may comprise an elbow 325 which is configured to connect to a conduit 122 (and for example provide the gases outlet 103). The elbow 325 may comprise one or more sensors.

[000227] To deliver the flow of gases to a patient from the conduit 122, the gas passing through the conduit can be delivered to a patient interface 124. The patient interface 124 can pneumatically link the respiratory therapy system 100 to a respiratory tract/ airway of a patient.

[000228] In the illustrated configuration, gas travels from the humidifier outlet 1 18 to the conduit 122.

[000229] The patient interface 124 can comprise a sealing or non-sealing interface, and can comprise a nasal mask, an oral mask, an oro-nasal mask, a full-face mask, a nasal pillows mask, a nasal cannula, an endotracheal tube, a combination of the above or some other gas conveying system.

[000230] In some configurations, a short length of tubing connects the interface 124 to the conduit 122. In some configurations, the short length of tubing can have a smooth bore, as described elsewhere herein. For example, a short flexible length of tubing can connect a nasal cannula or the like to the conduit 122. The short length of tubing connecting the interface to the conduit 122 may be breathable such that it allows the transmission of vapour through the wall of the tube. In some configurations, the short length of tubing can incorporate one or more heating wires as described elsewhere herein. The smooth bore, whether heated or not, can improve the efficiency in delivering nebulized substances, as described elsewhere herein.

Any other suitable patient interface 124 can be used.

[000231] In some configurations, the respiratory therapy system 100 comprises a humidifier 112. The humidifier 112 is used to humidify the flow of gases to the patient. The humidifier 112 is a gas humidifier that entrains moisture in the gas in order to provide a humidified gas stream. The illustrated gas humidifier 112 comprises a humidifier inlet 116 and a humidifier outlet 118. The gas humidifier 112 can comprise, be configured to contain or contain water or another humidifying or moisturizing agent (hereinafter referred to as water).

[000232] In some configurations, the gas humidifier 112 comprises a heating element. The heating element can be used to heat the water in the gas humidifier 112 to encourage water vaporization and/or entrainment in the gas flow and/or increase the temperature of gases passing through the gas humidifier 112. The heating element in some configurations can, for example, heat a resistive metallic heating plate, i.e. the heating element is configured to heat a heating plate. However, other heating elements are contemplated. For example, the heating element could comprise a plastic electrically conductive heating plate or a chemical heating system having a controllable heat output.

[000233] In some configurations, the flow generator 101 and the gas humidifier 112 may share a housing 126. In some configurations, the gas humidifier 112 may share only part of the housing 126 with the flow generator 101. Other configurations also are possible.

[000234] The flow generator 101 directs gas out through the gas outlet 104. In some configurations, the flow generator 101 directs gas out through to a connecting conduit 110. In the illustrated configuration, the connecting conduit 110 channels the gas to a gas humidifier 112.

[000235] In the configuration illustrated in Figure 5, the respiratory therapy apparatus 200 incorporates a humidifier with an integrated flow generator. In other words, in the illustrated configuration, a housing 202 contains a flow generator (not shown) and at least a portion of a gas humidifier 204. In the illustrated configuration, the flow generator and the gas humidifier 204 together form an integrated unit 206. In some configurations, the respiratory therapy system 100 can be the apparatus or system sold under the name AIRVO™ 2 by Fisher & Paykel Healthcare. Such an apparatus or system is shown and described, for example, in U.S. Patent No. 7,1 1 1,624, which is hereby incorporated by reference in its entirety. In some configurations, the respiratory therapy system 100 can be the apparatus or system sold under the name AIRVO™ 3 by Fisher & Paykel Healthcare. Such an apparatus or system is shown and described, for example, in PCT Application No. PCT/IB2016/053761 , which is hereby incorporated by reference in its entirety. Any other suitable configuration described in these applications can be configured with any of the components or configurations described in this specification.

[000236] The gas humidifier 204 in the illustrated integrated unit 206 employs a chamber 210. The chamber 210 can have any suitable configuration, including any configuration shown and/or described in U.S. Patent No. 7,146,979 and/or U.S. Patent No. 6,349,722, each of which is hereby incorporated by reference in its entirety. The chamber can contain or hold a volume of liquid, such as water, that is used to humidify gases as they pass through the chamber. In some configurations, the chamber simply defines a location in the system where liquid, such as water, is transferred into the gases stream or flow of gases.

[000237] As discussed above, gases that have been conditioned (e.g., heated and/or humidified) within the system 100 can be conveyed to a patient or other user. In some configurations, a tube or conduit 122 is used to convey the gases to the patient or other user. Some examples of conduits or tubes that can be used with the integrated unit 206 include, but are not limited to, those shown and described in U.S. Patent Publication No. 2014/0202462A1 (also published as WO2012/164407A1 ) and WO2014/088430, each of which being hereby incorporated by reference in its entirety. Any other suitable conduits or tubes also can be used.

[000238] In some configurations, the respiratory therapy system 100 may comprise one or more sensors for detecting various characteristics of gases in the respiratory therapy system 100, including pressure, flow rate, temperature, absolute humidity, relative humidity, enthalpy, gas composition, oxygen concentration, and/or carbon dioxide concentration, one or more sensors for detecting various characteristics of the patient or of the health of the patient, including heart rate, respiratory rate, EEG signal, EKG/ECG signal, blood oxygen concentration, blood CO2 concentration, and blood glucose, and/or one or more sensors for detecting various characteristics of gases or other objects outside the respiratory therapy system 100, including ambient temperature and/or ambient humidity. One or more of the sensors may be used to aid in the control of components (which may occur through use of the aforementioned controller) of the respiratory therapy system 100, including the gas humidifier 1 12, through the use of a closed or open loop control system.

[000239] With reference to figure 2, operation sensors 3a, 3b, 3c, such as flow, temperature, humidity, and/or pressure sensors can be placed in various locations in the breathing therapy system 100. Additional sensors (for example, sensors 20, 25) may be placed in various locations on the conduit 122 and/or patient interface 124 (for example, there may be a temperature sensor 29 at or near the end of the inspiratory tube).

[000240] With additional reference to Figure 3, a sensing circuit board 2200 is shown that can be implemented in the respiratory therapy system 100. The sensing circuit board 2200 can be positioned in a sensor chamber such that the sensing circuit board 2200 is at least partially immersed in the flow of gases. The flow of gases may exit the flow generator through a conduit and enter a flow path in the sensor chamber. At least some of the sensors on the sensing circuit board 2200 can be positioned within the flow of gases (shown in direction by arrow 2203) to measure gas properties within the flow. After passing through the flow path in the sensor chamber, the gases can exit to the humidifier 1 12 described above.

[000241] The sensing circuit board 2200 can be a printed sensing circuit board (PCB). Alternatively, the circuit on the board 2200 can be built with electrical wires connecting the electronic components instead of being printed on a circuit board. At least a portion of the sensing circuit board 2200 can be mounted outside of a flow of gases. The flow of gases can be generated by the flow generator 101 described above. The sensing circuit board 2200 can comprise ultrasonic transducers 2204. The sensing circuit board 2200 can comprise one or more thermistors 2205. The thermistors 2205 can be configured to measure a temperature of the gases flow. The sensing circuit board 2200 can comprise a thermistor flow rate sensor 2206. The sensing circuit board 2200 can comprise other types of sensors, such as humidity sensors (including humidity only sensors to be used with a separate temperature sensor and combined humidity and temperature sensors), sensors for measuring barometric pressure, sensors for measuring differential pressure, and/or sensors for measuring gauge pressure. The thermistor flow rate sensor 2206 can comprise a hot wire anemometer, such as a platinum wire, and/or a thermistor, such as a negative temperature coefficient (NTC) or positive temperature coefficient (PTC) thermistor. Other non-limiting examples of the heated temperature sensing element include glass or epoxy-encapsulated or non-encapsulated thermistors. The thermistor flow rate sensor 2206 can be configured to measure the flow rate of the gases by being supplied with a constant power, or by being maintained at a constant temperature or a constant temperature difference between the sensor and the flow of gases.

[000242] Positioning the one or more of thermistors 2205 and/or the thermistor flow rate sensor 2206 downstream of the combined flow generator and mixer means that the sensor readings will be dependent on the heat supplied to the gases flow by the flow generator. Furthermore, immersing at least part of the sensing circuit board and sensors in the flow path can increase the accuracy of measurements. Relative to sensors that are not immersed, sensors that are immersed in the flow are more likely to be subject to the same conditions, such as temperature and pressure, as the gases flow. Therefore, these immersed sensors may provide a better representation of the gases flow characteristics.

[000243] The sensing circuit board 2200 can comprise ultrasonic transducers, transceivers, or other sensors to measure properties of the gases flow, such as gas composition or concentration of one or more gases within the gases stream. Any suitable transducer, transceiver, or sensor may be mounted to the sensing circuit board 2200 as will be appreciated. In this configuration, the gas composition sensor is an ultrasonic transducer that employs ultrasonic or acoustic waves for determining gas concentrations.

[000244] Some examples of flow therapy apparatuses are disclosed in International Application No. PCT/NZ2016/050193, titled "Flow Path Sensing for Flow Therapy Apparatus", filed on December 2, 2016, and International Application No. PCT/IB2016/053761 , titled "Breathing Assistance Apparatus", filed on June 24, 2016, which are hereby incorporated by reference in their entireties. 2. Nebulized substance

[000245] In the preferred configurations, the respiratory therapy system 100 is configured to receive a nebulized substance and introduce it to the flow of gases to the patient. In some configurations, respiratory therapy system 100 comprises a port configured to be in fluid communication with a conduit for receiving a nebulized substance and introducing it to the flow of gases.

[000246] The nebulized substance typically is in the form of small aerosol/spray particles which can be carried by the flow of gases to be delivered to the patient. The nebulized substance is mixed, combined with, or otherwise carried with the flow of gases delivered to the patient. The nebulized substance may be a 'particle,' or 'droplet' i.e., aerosolized solid or liquid respectively and both the terms particle and droplet may be used interchangeably as the nebulized substance introduced in the system.

[000247] In the illustrated configuration, and as implied above, the respiratory therapy system 100 can operate as follows. Gases can be drawn into the flow generator 101 through the gas inlet 102 due to the rotation of an impeller of the blower 106 by the motor. The gases are propelled out of the gas outlet 104 and through the connecting conduit 1 10. The gases enter the gas humidifier 1 12 through the humidifier inlet 1 16. Once in the gas humidifier 1 12, the gases entrain moisture when passing over or near water in the gas humidifier 1 12. The water is heated by the heating element, which aids in the humidification and/or heating of the gases passing through the gas humidifier 112. The gases leave the gas humidifier 1 12 through the humidifier outlet 1 18 and enter the conduit 122. Prior to entering the conduit 122, the gases flow receives (and entrains) one or more substance from a nebulizer 128. The gases flow is directed from the conduit 122 to the patient interface 124, where the gases flow is taken into the patient's airways to aid in the treatment of respiratory disorders.

[000248] In some configurations, a sufficient amount of the nebulized substance being delivered to the patient via the gases flow travels to a desired target location in the patient's respiratory tract or airways. The size of particles of the nebulized substance can affect the travel, dispersion and/or deposition behavior of the substance in the patient's respiratory tract or airways. The 'particle size' may refer to the average size of particles of the substance, as quantified by various measures or parameters, for example, mass median aerodynamic diameter (MMAD).

[000249] Typically, a gases flow carrying nebulized substance(s) with a smaller average particle size may be able to travel a greater distance into the patient's respiratory tract or airways before being dispersed or deposited on surfaces of the respiratory tract or airways. The nebulized substance's particle size may also affect the deposition and retention of the substance in the respiratory tract (i.e., how effectively particles of the substance remain dispersed or deposited in the respiratory tract or airways). However, if the particle sizes are too small, some proportion of the delivered substance may not be deposited (or remain deposited) in the patient's airways, instead being exhaled out by the patient's breathing. Dependent on various factors — including the composition of the substance being nebulized and the condition of the patient being treated — it may be desirable for: a) as much of the substance as possible to be deposited or dispersed into the patient's respiratory tract, or b) some of the substance to exhaled or partially exhaled out of the patient's respiratory tract. Thus, it is desirable for a clinician to be able to have control over the average size of the particles of the nebulized substance being provided in a respiratory therapy system.

[000250] In some configurations, the respiratory therapy system 100 controls at least one component to regulate particle size of the nebulized substance. The respiratory therapy system 100 controls parameters of the system by controlling specific components internal in the system e.g. by adjusting power provided to a heater wire in the breathing tube conduit and/or blower fan speed (more examples provided below). Controlling these internal or built-in components of system can provide a more direct influence on the particle size of the nebulized substance in the gases flow path, closer to being received by the patient. Regulation of particle size in these configurations does not occur external to the system e.g. by the nebulizer itself. The control e.g. of humidity internally in the system to regulate particle size of the nebulized substance is different to and may be additional to any regulation of particle size that may occur upstream of the respiratory therapy system e.g. prior to being chamber 210. An advantage of controlling the humidity and thus particle size of the nebulized substance in the system is that there is more direct, predictable and/or more measurable control of the substance close to deliver to the patient (i.e. the control/ regulation of the particles occurs downstream of chamber, and close to the end of the flow path of the system/ close to the patient end of the system.)

[000251] In one or more configurations, the controller 1 13 is configured to adjust power provided to a component in the system to regulate the average particle size of the nebulized substance to a target. In some of these configurations, adjusting the power delivered to a component in the system in turn affects the amount of heat imparted to the flow of gases in the system at different points in the flow pathway, e.g., heat applied to water in a chamber of the humidifier or heat applied to the flow of gases in the conduit.

[000252] In some configurations, regulation of the nebulized substance average particle size could also be achieved through a controller method that varies one or more built-in functions that will affect the relative humidity of the gases flow being provided to a patient. This controller method could involve controlling any number of dynamically controllable features such as impeller or pump speed to change air/gases flow rate, the opening extent of control valves, apertures, or other restrictions, control of the air-water contact area and residence time in the humidifier chamber or other areas of the system (through features such as baffles and/or other ways of creating a tortuous flow path), control of additional heating or cooling elements in the system, and/or length of the conduits within the system.

[000253] When nebulized substances are introduced into the respiratory therapy system 100, the particles are suspended and/or carried in the flow of gases. The average size of the particles can affect how far the substance is carried by the flow of gases into the patient's airways and thus the distance of travel. Relatively larger particle sizes of these nebulized substances (for example, an average particle size of > 1 pm MMAD) tend to deposit in the upper respiratory tract (e.g., oronasal passages), whereas smaller droplet sizes (for example, average particle size < 1 pm MMAD) in a humidified gases flow can travel further into the airways. In the preferred configurations, the average particle size can be regulated inside the system 100, as the particle size is influenced by factors within the system.

[000254] Managing the particle sizes of nebulized substances can be achieved in some configurations at least in part by to adjusting the relative humidity of the humidified gases being delivered to the patient. In some respiratory therapy systems with breathing gas humidification, it may be desired for the control systems to aim to maintain relative humidity at 100% (i.e., fully saturating the gases flow, thereby mimicking the natural humidification performed by the airways of a patient). However, at least at some flow rates, and for some substances being nebulized, at 100% relative humidity the particle size will be higher than desirable (e.g., >1.0 pm) to disperse or deposit the substance at a particular depth into the patient's airways. Thus, in the preferred configurations, the respiratory therapy system 100 controls components of the system to affect humidity such that a target relative humidity of below 100% is achieved.

[000255] It is anticipated that controlling components of the respiratory therapy system 100 to affect the relative humidity of the flow of gases in such a way as described (i.e., to affect the average particle size of the nebulized substance) helps improve the likelihood that a sufficient quantity of the nebulized substance reaches the desired location for dispersion or deposition in the airways of the patient. Control of components in the respiratory therapy system 100 to achieve a target relative humidity will be described in more detail later.

[000256] In some configurations, the controller 1 13 is configured to at least adjust power provided to the heater wire 123 to regulate the average particle size of the nebulized substance to or towards a target i.e. adjust power to achieve target particle size. In some of these configurations, the target average particle size is based on a desired distance of travel into the patient's airways. If the desired location of dispersion or deposition of the nebulized substance is further or deeper into the airways, the desired distance of travel for particles of the nebulized substance is greater than if the desired location is not as far into the patient's airways.

[000257] In some configurations, the desired distance of travel may be for the dispersion or deposition to predominantly occur in or around the patient's upper respiratory tract. In these configurations, the distance of travel for particles of the nebulized substance is shorter than if the desired distance of travel was such that dispersion or deposition predominantly occurs in the lower respiratory tract. [000258] In other configurations, the desired distance of travel is for dispersion or deposition predominantly beyond the patient's upper respiratory tract. In these configurations, the distance of travel for particles of the nebulized substance is greater than if the desired distance of travel was to a region in the upper respiratory tract. To achieve this (i.e., for a sufficient quantity of the nebulized substance particles to travel a greater distance to a deeper region of the patient's airways), the average particle size of the nebulized substance particles is in some configurations smaller than if the desired distance of travel were to a region in or around the patient's upper respiratory tract. In summary, in some configurations, the target average particle size is relatively larger when the desired distance of travel is for dispersion or deposition in or around the patient's upper respiratory tract than the target average particle size when the desired distance of travel is for dispersion or deposition in or around the patient's lower respiratory tract.

[000259] In some configurations, the desired distance of travel is for dispersion or deposition in or around the patient's lower respiratory tract.

[000260] In some configurations, the target average particle size (of a nebulized substance being delivered to a patient via the flow of gases) is a mass median aerodynamic diameter (MMAD) of <1.0 pm (micrometers).

[000261] In some configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.5 pm and 1.0 pm.

[000262] In other configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of <0.5 pm.

[000263] In other configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.1 pm and 0.5 pm.

[000264] It is anticipated that different target average particle sizes may be dependent on the specific nebulized substance being delivered. As such, the specific controls of the system to deliver the nebulized substance to a desired location in the patient's respiratory tract will vary. The hygroscopic properties of the substance, e.g., its hygroscopicity — how readily it will agglomerate with water vapor suspended in the gases flow — may also affect how large the particle size(s) become. Highly hygroscopic substances may tend to absorb much more water vapor from the humidified gases flow, resulting in larger particle sizes, whereas weakly hygroscopic or even non-hygroscopic substances may have the opposite tendency, with particles not absorbing any or as much water vapor. Thereby the weakly hygroscopic or non- hygroscopic substances remain the same size or smaller than highly hygroscopic substances . That is, the weakly hygroscopic or non-hygroscopic substances may stay approximately the same size as when dispensed from the nebulizer. As a further example, specific substances that have different dew point, heat capacities, and evaporative properties may require their own specific settings or modes. Factors that may affect the controls settings required include but are not limited to mixes of differing concentrations of oxygen in the air flow, different nebulizer substances (e.g., medications or other drugs) and concentrations (e.g., the osmotic concentration or osmolarity of particular solutions of substance(s) being nebulized).

[000265] The nebulized substance being introduced to the flow of gases may be a medicinal substance. Other examples of nebulized substances that could be introduced to the flow of gases may be: mannitol, lactated Ringer's solution, 5.0% dextrose in water, Hartmann's solution, sodium lactate solution, and compound sodium lactate. The substance is introduced into the system 100 and can be carried by the gas flow, then delivered along with the respiratory gases to the airways or respiratory tract of the patient.

[000266] In some configurations, the introduction of the nebulized substance into the flow of gases delivered to a patient can improve treatment of respiratory diseases or disorders.

[000267] With continued reference to Figure 1, in some configurations, a nebulizer 128 can be used with the respiratory therapy system 100. The nebulizer 128 may be independent of, or form part of the respiratory therapy system 100.

[000268] The nebulizer 128 produces a fine spray of liquid i.e., aerosol of particles. The nebulized substance is introduced into the flow of conditioned gases or pre-conditioned gases. Any suitable nebulizer 128 can be used. [000269] In some configurations, a port for the nebulizer to dispense the nebulized substance into the gases flow path is located downstream from the flow generator 101. In these configurations, the nebulized substance will be carried by the flow of gases from the flow generator 101.

[000270] In some configurations, the port for the nebulizer is located at the humidifier 112. The nebulized substance in these configurations is added to a humidified flow of gases to be delivered to the patient. In some configurations, the port for the nebulizer is located at or towards an inlet 116 or outlet 118 of the humidifier 112. In some configurations, the port for the nebulizer is located at or towards an outlet of the humidifier. In some configurations, the port for the nebulizer is located downstream of the humidifier.

[000271] In some configurations, the port for the nebulizer is located upstream from a device end of the conduit 122 (patient breathing tube) of the breathing therapy apparatus. In other configurations, the port for the nebulizer is located at or towards a device end of the conduit. In these configurations, the nebulized substance introduced to flow of gases, form part of the flow of gases mixture by the time it enters the conduit so that adjusting power to the heater wire 123 in the conduit can have an effect on the particle sizes of the nebulized substance(s). In some configurations, the port for the nebulizer is located at or in the conduit. In other configurations, the port for the nebulizer is positioned at any or at various locations along the conduit. For example, the port for the nebulizer may be positioned at or in the conduit, approximately one-third of the distance from the device end, or half the distance from the device end, or two-thirds of the distance from the device end. In other, configurations, the port for the nebulizer is located at or towards a device end of the conduit.

[000272] In some configurations, the conduit 122 comprises a length of greater than 0.5 meters. In some configurations, the conduit comprises a length of greater than 1 meter. In some configurations, the conduit comprises a length of greater than 1.5 meters. In some configurations, the conduit 122 has a length such that the residence time of the flow of gases and nebulized substances is sufficient for adjustments to the power of the heater wire 123 to affect the relative humidity inside the conduit and thereby adjust the average particle size of the nebulized substance to or towards the target particle size. In some configurations, the forementioned controls are sufficient to affect the relative humidity in the system to adjust the average particle size of the nebulized substance to the target particle size.

[000273] In some configurations, multiple components of the respiratory therapy system may be housed together. For example, two or more of the flow generator 101, the gas humidifier 112, and the nebulizer 128 can share a housing 126.

[000274] In some configurations, the nebulizer 128 is separate from the housing 126. In these configurations, the nebulizer 128 can be linked to a portion of the gas passageway extending between the flow generator 101 (which may include the gas inlet 102) and the patient interface 124, although other arrangements for the nebulizer 128 or another nebulizer may be utilized.

[000275] In some configurations, the nebulizer 128 is not positioned in-line in any location between the humidifier outlet 118 and the patient interface 124. Rather, the nebulizer 128 can be positioned upstream of the humidifier outlet 118 or upstream of the inlet to the conduit 122. In some configurations, the nebulizer 128 can be positioned upstream of an inlet into the humidifier. In some configurations, the nebulizer 128 can be positioned between the source of gases flow and a chamber of the humidifier.

[000276] In some configurations, the position or location of the nebulizer port defines the flow path of the nebulized substance. The flow path may include all or some parts of the device outlet, elbow, humidification chamber, conduit and/or patient interface.

[000277] In the illustrated configuration of figure 5, an outlet 129 of the nebulizer 128 is positioned to connect with the chamber 210 to introduce the nebulized substance. In some configurations, the nebulizer 128 is configured and positioned to inject the nebulized substance into a conditioned gases flow downstream of the chamber 210 and upstream of the conduit 122 that connects a patient interface 124 to the integrated unit 206. In some configurations, the nebulizer 128 is configured and positioned to inject the nebulized substance into the conditioned gases flow downstream of the chamber 210 and upstream of a connection location for the removable conduit 122 with the integrated unit 206. In some configurations, the nebulizer 128 is configured and positioned to inject the nebulized substance into the gases flow prior to entry into the chamber 210. In some configurations, the nebulizer 128 is configured and positioned to inject the nebulized substance into the gases flow during entry into the chamber 210. In some configurations, the nebulizer 128 is configured and positioned to inject the nebulized substance into the gases flow following entry into the chamber 210. In some configurations, the nebulizer 128 is configured and positioned to inject the nebulized substance into the gas flow prior to exit from the chamber 210. In some configurations, the nebulizer 128 is configured and positioned to inject the nebulized substance into the gas flow during exit from the chamber 210. In some configurations, the nebulizer 128 is configured and positioned to inject the nebulized substance into the gas flow following exit from the chamber 210.

[000278] In some configurations, the port is configured to receive the nebulizer indirectly. The respiratory therapy system may have a connector configured to be connected to the port at one opening, and for receiving the nebulizer at another opening. In these configurations, a nebulizer is not directly connected at the port as there is a connector or conveyor to connect between the nebulizer and the port.

[000279] The nebulizer 128 can be linked to the portion of the gas passageway by a connector or conveyor 130, which can comprise a conduit or an adaptor. Alternatively, the nebulizer 128 can interface directly with the gas passageway, which can render the conveyor 130 unnecessary.

3. Controller

[000280] In some configurations, the operation of the flow generator 101, of the gas humidifier 112, or of other components or aspects of the respiratory therapy system 100 may be controlled by a controller 113. The controller may comprise a microprocessor, applicationspecific circuitry such as ASICs or FPGAs, or other suitable devices. The controller may be located in or on the flow generator 101, the gas humidifier 112, or other components of the respiratory therapy system 100 or on a remote computing device that is in remote communication with the respiratory therapy system 100. In some configurations, multiple controllers may be used.

[000281] With reference to figure 2, in such configurations, the respiratory therapy system 100 can control operation of components of the system, control actions including but not limited to: adjusting power delivered to the heater wire 123 of the heated breathing conduit (to adjust the temperature in the heated breathing conduit), and power delivered to the heating element 25 of the humidifier (to adjust heating of water in humidifier).

[000282] In some configurations, a controller 113 adjusts power provided to the heater wire 123 of the conduit 122 to regulate the average particle size of the nebulized substance towards a target. For example, in some configurations, the temperature within the conduit 122 downstream of the nebulizer 128 (when connected to the respiratory therapy system 100) can be controlled to or towards a target to adjust the relative humidity of the gases flow within the conduit towards a target.

[000283] The relative humidity of the humidified gases being delivered to the patient may be controlled dynamically by the respiratory therapy system 100 by increasing or decreasing the temperature of the heated conduit 122 relative to the temperature at the heating element 25 of the humidifier (for example, by adjusting the power delivered to the heater wire). For example, increasing the temperature of the heated conduit 122 and/or reducing the power supplied to the heating element 25, would lower the relative humidity of the humidified gases being delivered to the patient. A reduction in the relative humidity of gases being delivered to the patient may be achieved when there is a sufficient temperature differential between the temperature at the outlet of the humidifier and the temperature at the patient (e.g., as measured by a patient-end temperature sensor positioned in the conduit). A sufficient temperature differential may be approximately 5 degrees Celsius. Smaller or larger temperature differentials may also be suitable. It should be appreciated that adjusting the power delivered to the heater wire of the heated conduit 122 allows for faster changes to the relative humidity, and thus the average particle size of the nebulized substance(s) in the conduit 122. Adjusting power delivered to the heater wire may be quicker in comparison to heater water in the chamber by adjusting the power delivered to the heating element of the humidifier. One or both controls to power delivered to the heater wire or the heating element 25 humidifier may be used to achieve the desired humidity.

[000284] It is typically preferable when controlling a respiratory therapy system with a humidification to control the power delivered to the heater wire and the heating element in tandem so as to maintain 100% relative humidity and a certain absolute humidity (e.g., 44 mg/L). In contrast, in the preferred configurations of the present respiratory therapy system 100, the controller 113 may increase power to the heater wire of the heated conduit 122 relative to the heating element 25 of the humidifier (i.e., not in tandem), thus causing relative humidity to decrease, and the average particle size of the nebulized substance to decrease.

[000285] In some configurations, the power delivered to the heater wire 123 of the heated conduit 122 can be controlled to achieve the relative humidity target after the nebulizer 128 is installed and dispensing the nebulized substance. In some configurations, power to the heater wire 123 in the conduit 122 can be controlled to achieve the relative humidity target prior to initiating nebulization of the substance into the flow of gases by the nebulizer 128.

[000286] In some configurations, a controller 113 adjusts the power supplied to the heating element 25 of the humidifier to regulate the average particle size of the nebulized substance towards a target. It should be appreciated adjusting power to the heating element 25 will have a slower effect on the temperature of the gases flow (due to both the thermal inertia of the humidifier heater plate and the body of water stored in the humidification chamber), and thus the relative humidity will change more gradually in response to adjustments of power. As noted, this is because of the thermal inertia of the heater plate and water in the humidification chamber — it may take a comparatively long period of time to cool or heating a relatively large body of water.

[000287] In some configurations, the controller controls both the power supplied to the heater wire and the power delivered to the heating element to achieve a target average particle size. [000288] In some configurations, the temperature (or a parameter related to the temperature, e.g., the duty cycle of a heating/control signal) of the heating element 25 and/or the conduit 122 can be maintained for a predetermined period of time (or a period of time that is a function of the flow rate, for example). Such configurations can help account for thermal inertia in the system while protecting the nebulized substance from excessive heating and/or possible thermal damage that could compromise the efficacy of the substance.

[000289] In some configurations, the controller 113 can control the power supplied to the heater wire 123 of the conduit 122 independent of the control of power supplied to the heating element 25 of the humidifier, in order to regulate average particle size. For example, there may be two separate control loops for each of the components. In some configurations, the heater wire 123 may not be controlled in strict cooperation or synchronisation with the heating element, which may itself controlled so as to achieve an absolute humidity target or set-point. In some configurations, the heater wire 123 is controlled to heat the flow of gases in the conduit 122 to achieve a relative humidity target or set-point. That is, the control loop for the heater wire 123 may be independent of the control loop for the heating element of the humidifier. The heater wire 123 in these configurations may be controlled independently of the heater element of the humidifier to target a certain relative humidity and thus target a desired average particle size for a substance being nebulized into or added to the gases flow delivered to a patient.

[000290] The particle sizes of the nebulized substance may also be influenced by other parameters of the flow of gases in the system — for example, when flow is turbulent (such as may occur once the flow reaches the patient e.g., towards the nose), the particles may be more likely to coalesce or agglomerate, increasing their size.

[000291] In some configurations, the system comprises a standard therapy mode and a nebulization therapy mode. The standard therapy mode can be a mode in which the system operates when a nebulized substance is not being added to the flow of humidified gases or has not been introduced yet. [000292] In some configurations, in the nebulization therapy mode, a relative humidity of the flow of gases targeted by the controller 113 is lower than a target relative humidity in the standard therapy mode. In the nebulization therapy mode, power delivered to a component may be increased, resulting in a lower relative humidity, depending on the desired average particle size. In some of these configurations, the standard therapy mode may target a relative humidity of approximately 100% while the nebulization therapy mode may target a relative humidity of less than 100%.

[000293] In some configurations, the target relative humidity in the nebulization therapy mode is less than 80%. In some configurations, the target relative humidity in the nebulization therapy mode is less than 60%.

[000294] In some configurations, the power supplied to the heater wire in the nebulization therapy mode is higher than the power supplied in the standard therapy mode.

[000295] In some configurations, a user can manually adjust between the standard therapy mode and the nebulization therapy mode. The modes may be adjusted by a user interface on the device.

[000296] In some configurations, in the nebulization therapy mode, the target relative humidity is configurable by a user (e.g., a clinician). This can be directly (e.g., the user selects a desired dew point temperature) or indirectly, where the user selects a desired particle size and/or substance composition (e.g., a saline solution concentration)). In some configurations, a user interface feature (e.g., a touch screen element) for manually adjusting the target average particle size becomes available to interact with after entering nebulization therapy mode.

[000297] In some configurations, the system is configured to automatically control power delivered to the heater wire to achieve a default target average particle size (e.g. when in nebulization therapy mode). [000298] In some configurations, the system is to automatically control power delivered to the heating element to achieve a default target average particle size. In some configurations, the default target average particle size is <1.0 pm.

[000299] In some configurations, in nebulization therapy mode, the flow rate range of the flow of gases may be within a set flow rate range. The set flow rate range may be between approximately 30 L/min and approximately 50 L/min, but other flow rates may be suitable. In some configurations, the controller is configured to adjust the speed of the blower. In some configurations, the speed of the blower is adjusted to provide the flow rate range of the flow of gases within the set flow rate range. The speed of the blower is adjusted such that the flow rate of the flow of gases within the set flow rate range.

[000300] In some configurations, the flow rate of the flow of gases may by higher or lower than the set flow rate range. When the nebulization therapy mode is activated, the speed of the blower may be adjusted to provide the flow rate range of the flow of gases within the set flow rate range.

[000301] In some configurations, the flow rate range of the flow of gases may be higher than the set flow rate range. When the nebulization therapy mode is activated, the controller is configured to decrease the speed of the blower to provide the flow rate range of the flow of gases within the set flow rate range. Optionally, the controller is configured to decrease the speed of the blower to provide the flow rate range of the flow of gases within an upper region of the set flow rate range. For example, if the flow rate of the flow of gases is 60 L/min, and the set flow rate range is between approximately 30 L/min and approximately 50 L/min, when the nebulization therapy mode is activated, the flow rate of the flow of gases may be decrease to approximately 50 L/min.

[000302] In some configurations, the flow rate range of the flow of gases may be lower than the set flow rate range. When the nebulization therapy mode is activated, the controller is configured to increase the speed of the blower to provide the flow rate range of the flow of gases within the set flow rate range. Optionally, the controller is configured to increase the speed of the blower to provide the flow rate range of the flow of gases within an upper region of the set flow rate range. For example, if the flow rate of the flow of gases is 20 L/min, and the set flow rate range is between approximately 30 L/min and 50 L/min, when the nebulization therapy mode is activated, the flow rate of the flow of gases may be increased to approximately 30 L/min.

[000303] The flow rate of the flow of gases is limited to a set flow rate range to reduce the probability of the nebulized substance depositing in the flow path and/or reduce the volume of nebulized substance depositing in the flow path. For example, at higher flow rates a higher volume of nebulized substance may be deposited in the flow path and less of the nebulized substance may reach the patient. In nebulization therapy mode, it may be desirable to decrease the flow rate of the flow of gases to a relatively lower flow rate. Decreasing the flow rate of the flow of gases to a relatively lower flow rate may promote delivery of nebulized substances to the patient/user's airways. A relatively lower flow rate may be between approximately 10 L/min to approximately 30 L/min, for example, but other flow rates may be suitable.

[000304] In some configurations, the humidification apparatus is configured to cause or produce an alarm when the nebulization therapy mode is activated and the flow of gases is higher or lower than the set flow rate range. In some configurations, the nebulization therapy mode is active for a set period of time. In some configurations, the humification apparatus is configured to cause or produce an alarm when the period of time the nebulizer therapy mode is active is longer than the set period of time.

4. Relative Humidity

[000305] It should be understood that the particle size of the nebulized substance is influenced by a number of factors within the respiratory therapy system 100.

[000306] For example, the relative humidity in the conduit 122 can influence particle size (e.g., MMAD) of the nebulized substance. In the system, the relative humidity can be considered the amount of water vapor in the mixture of gases as a percentage of the maximum amount it could hold at a particular temperature. Whereas the absolute humidity is the actual or absolute amount (i.e., quantity) of water vapor carried by in the gases flow in the system, regardless of the temperature of the flow (e.g., in milligrams of water per liter of gases, mg/L). [000307] Adjusting the relative humidity in the respiratory therapy system 100 can affect the particle sizes of the nebulized substance, as the nebulized particles tend to adsorb (if the particles are relatively dry) and then absorb (if the particles are relatively wet) water, becoming larger in the process.

[000308] In humidified respiratory therapies, the desired relative humidity is typically controlled to be as close to 100% as possible, in order to mimic the natural humidification performed by the upper respiratory passages. However, it has been found that water vapor particles may coalesce with particles of nebulized substance to form larger particles, resulting in an increased MMAD (as described above), and therefore the substance may not travel into the respiratory tract as desired, and/or in sufficient quantity. Thus, it may be desirable to reduce the degree of saturation (i.e., relative humidity) of the humidified gases flow to a lower target in order to affect particle size of the nebulized substance, and thereby the distance travelled by the nebulized substance into the patient's respiratory tract. In effect, reducing the relative humidity may effect an increase in the evaporation effect, leading to desorption of water from the nebulized substance particles, and thereby resulting in decreased MMAD.

[000309] In some configurations, the target relative humidity is approximately 80%. In other configurations, the target relative humidity is less than 80%. For some nebulized substances, a relative humidity of approximately 80% or less will keep the average particle size of the nebulized substance at or below 1.0 pm. In some configurations, such parameters will be sufficient for the nebulized substance to travel to at least the upper respiratory tract.

[000310] In some configurations, the target relative humidity is approximately 60%. In other configurations, the target relative humidity is less than 60%. For some nebulized substances, a relative humidity of approximately 60% or less will keep the average particle size of the nebulized substance at or below 0.5 pm. In some configurations, such parameters will be sufficient for the nebulized substance to travel to the lower respiratory tract.

[000311] It is anticipated that different relative humidity targets may be necessary for different nebulized substances being delivered. As such, the specific control parameters of the system selected to deliver the nebulized substance to a desired location in the patient's respiratory tract will vary. For example, a clinician or other suitable person may specify the type and/or concentration of active substance in the solution to be introduced into the system 100 as the nebulized substance. The controller 113 may adjust the relative humidity of the gases flow carrying the nebulized substance by maintaining or adjusting settings for one or more components accordingly. Higher concentrations of active substance generally require relative humidity to decrease more in order to regulate the particle size to the desired target e.g., MMAD < 1.0 pm, in order to pass through the upper and proximal airway passages, while lower concentrations may only require relative humidity to decrease by a smaller amount.

[000312] In some configurations, where the nebulized substance introduced into the respiratory therapy system 100 comprises different solution compositions, adjustments to the relative humidity can be used to maintain a desired average particle size. If the substance composition changes during a respiratory therapy session — for example, due to a clinician increasing or decreasing the dosage of a medication — the system can adjust the target relative humidity in order to maintain a desired average particle size. If the change in substance composition is such that the present relative humidity will result in an undesirably large average particle size (with the current settings), the system can effect a decrease in the relative humidity, for example, following interaction with the controls of the system by the clinician (e.g. via a user interface), and vice-versa.

[000313] It should be appreciated that in some of these configurations, the user does not need to wait for the absolute humidity of the gases flow to decrease or increase (by cooling or heating the water in the humidifier) post-adjustment of the nebulized substance. The clinician or other user can specify to the system that the particle size needs to decrease or increase, and the system can accordingly control components such as the heater wire to adjust the relative humidity quickly. Thus, in these configurations, the workflow for a clinician or other user may be considerably more straightforward and/or fast.

[000314] With reference to figures 8A and 8B, test results confirm a correlation between relative humidity, air temperature, and the MMAD of the nebulized substance(s) in the system. It can be seen that as the air temperature deviates from the dew point (and thus the relative humidity decreases), the MMAD of the nebulized particles suspended in the gases flow is reduced. Figures 8A and 8B show the MMAD of nebulized particles across a range of carrier air conditions at a gases flow rate of 20 L/min and 40 L/min respectively. The average size of particles is largely unaffected by these differences in flow rate. However, at much lower flow rates (e.g., 2-3 L/min), the nebulized particles will spend a significantly longer in the humidified flow of gases, which may promote and allow for more growth in the size of the particles, i.e., by adsorption of water vapour and other mechanisms. The graph also demonstrates that the concentration of saline solution (a proxy for other nebulized formulations in this situation) in the nebulized solution can have a significant impact on the MMAD of the nebulized particles suspended in the gases flow. As above, relative humidity is affected by increasing or decreasing the gases flow temperature. Alternatively, the absolute humidity (AH) can be reduced e.g. by increasing the flow rate to reduce residence time of gases flowing through the chamber and/or reducing power supplied to the heater plate to reduce how much the water is heated. The reverse can be done to increase absolute humidity and thereby relative humidity. Higher flow rate will reduce the residence time of gases in the heated breathing tube, which might reduce the temperature of gases received by the patient (if power to the heated breathing tube is not correspondingly increased). Further, the concentration of substance in the solution being nebulized (e.g., how much NaCI or medicament versus water) will have an effect on the MMAD of particles, but is chosen externally to the system and typically depends on what the patient is deemed to need. To summarize, the key physical variables that may affect the MMAD of particles are temperature, absolute humidity, and nebulized drug formulation.

[000315] As those graphs show, when the substance is a saline solution of 0.9% sodium chloride (NaCI), a higher relative humidity may be suitable for a particular desired MMAD, whereas at a higher concentration of NaCI (7.0%), the MMAD is much higher at the same relative humidity. As described above, higher concentration solutions of the nebulized substance generally require relative humidity to decrease more in order to regulate the particle size to the desired target, in comparison to lower concentrations where the relative humidity may only be required to decrease by a smaller amount to achieve a desired target particle size.

[000316] In the preferred configurations, the controller 113 in the system adjusts settings such as the power supplied to the heater wire 123 of the conduit, or the power of the heating element 25 based on the desired average particle size (e.g., MMAD). Adjusting these settings can adjust and in some configurations reduce the relative humidity of the humidified air in the conduit 122, which will reduce the size of the particles in the gases flow to a desired average size, allowing for nebulized substance particles to travel a desired distance into the patient's respiratory tract.

[000317] In the preferred configurations, the controller 113 controls components of the system to reach a target relative humidity (which regulates the particle size of the nebulized substance, as discussed). The target relative humidity may be specific to a region in the system. In some configurations, the target relative humidity is the relative humidity of the flow gases in the conduit 122. In some configurations, the target relative humidity is the relative humidity of the flow gases at a patient end of the conduit. The target relative humidity being at the patient end can be adjusted and achieved after the flow of gases has been heated through the flow passage along the length of the conduit 122.

[000318] In some configurations, the controller 113 controls the power supplied to the heater wire to reach a target relative humidity. In some configurations, the controller continually controls the power supplied to the heater wire to maintain a target relative humidity. The power supplied to the heater wire may be adjusted by varying the duty cycle of a pulse-width modulated (PWM) signal to the heater wire, and/or varying the voltage magnitude of a DC voltage provided to the heater wire.

5. User control interface

[000319] In some configurations, the respiratory therapy system 100 may comprise a user control interface. The user control interface 108 can comprise one or more buttons, knobs, dials, switches, levers, touch screens, speakers, displays, and/or other input or output modules that a user might use to input commands into the flow generator 101, to view data, and/or to control operations of the flow generator 101, and/or to control operations of other aspects of the respiratory therapy system 100. The system in some configurations may have multiple user control interfaces 108, 120 at different locations in the system 100, such as illustrated in figure 1. [000320] In some configurations, the user control interface comprises a user control interface element for adjusting the target average particle size.

[000321] In some configurations, the user control interface comprises a user control interface element for adjusting a target distance of travel into the patient's respiratory tract.

[000322] In some configurations, the user control interface comprises a user control interface element for selecting a standard therapy mode and a nebulization therapy mode.

[000323] In some configurations, the operation of components of the respiratory therapy system 100 may be controlled wirelessly using a user control interface located on a remote computing device, which may be a tablet, a mobile phone, a personal digital assistant, or another computing device.

6. Method of Use

[000324] In some configurations, the respiratory therapy system 100 may be set up as follows. The steps can be conducted in any suitable order and, therefore, the following is a mere example of the order that can be used.

[000325] In some configurations, the respiratory therapy system 100 can be used with the nebulizer 128 and conduit 122 to provide any desired therapy capable of being performed with the combination of components. In some configurations, a nasal cannula (being the patient interface 124) is connected to the conduit and nasal high flow therapy is provided while dispensing a substance (e.g., a saline solution or a drug) into the gases flow via the nebulizer. An advantage of using high flow therapy while dispensing a substance is that the high flow rate of gases pushes the nebulized particles within the gases into the airways of the patient. A high flow rate may increase the probability and/or the volume of the nebulized substance depositing in the airways of the patient and/or further into the airways. Other configurations and methods also are possible.

[000326] With reference to figure 7, there is a flow diagram of the steps for method of use. Different configurations may include one or more of these steps. [000327] In some configurations, a user selects a desired particle size of the nebulized substance on a user control interface. For example, by actuating a physical element (e.g., slider, button etc.), or a digital interface element (i.e., a touch screen) to select a particle size. The particle sizes selected may be a particle size with a particular desired MMAD, or in other configurations by selecting a specific particle size mode e.g., small, regular, large particle size mode. Alternatively, a user may be able to select a desired deposition or dispersion region. In some configurations, other modes may be detected or selected e.g. type of patient interface connected. The mode detected by the system or selected by the user can initiate predetermined controls (such as the power delivered to components of the system) to adjust the relative humidity, which adjusts the average particle size of the nebulized substance being delivered, which then affects the delivery of the nebulized substance to the patient.

[000328] In the preferred configurations, once an input is provided, the power supplied to the heater wire of the conduit and the power delivered to the heating element of the humidifier and/or other components of the system 100 is adjusted based on the desired particle size, desired deposition or dispersion region in the patient, type of patient interface, or other parameter. For example, clinicians may want different desired MMADs, desired dispersion or deposition regions based on the type of patient interface being used, such as a nasal cannula, a face mask, an oral interface, or a tracheostomy interface. Reducing the relative humidity of the humidified air in the conduit 122, reduces the size of the particles of liquid to the desired MMAD, allowing for nebulized substance particles or droplets to travel the desired distance into the patient's respiratory tract (further distance into the patient's respiratory tract than if relative humidity was higher). Alternatively, increasing the relative humidity of the humidified air in the conduit 122, increases the size of the particles of liquid to the desired MMAD, allowing for nebulized substance particles or droplets to travel the desired distance into the patient's respiratory tract (shorter distance than if relative humidity was lower).

7. General description of respiratory therapy apparatus

[000329] In some configurations, there is provided a respiratory therapy apparatus 200 for delivering a flow of gases to a patient. The respiratory therapy apparatus 200 comprises a flow generator 101 101 configured to generate the flow of gases; a humidifier 1 12 comprising a heating element 25; a port configured to be in fluid communication with a conduit 122 and a controller 113. The port may be configured to receive a nebulized substance and introduce the nebulized substance to the flow of gases to the patient. The controller 113 may be configured to adjust power delivered to at least the heating element 25 to regulate an average particle size of the nebulized substance to or towards a target.

[000330] In some configurations, the apparatus is configured to fluidly connect to a conduit 122. The conduit 122 may be configured to deliver the flow of gases from the flow generator 101 to the patient. The conduit 122 may comprise of a lumen and a heater wire 123 configured to heat the flow of gases in the conduit 122.

[000331] In some configurations, the controller 113 is configured to adjust power delivered to a heater wire 123 to regulate average particle size of the nebulized substance to a target. The controller 113 may control both the power delivered to the heater wire 123 and the power delivered to the heating element 25 to achieve target average particle size. The controller 113 may control the power delivered to the heater wire 123 independently from the power delivered to the heating element 25 to regulate average particle size. The controller 113 may control the power delivered to the heating element 25 and/or the heater wire 123 to reach a target relative humidity. The controller 113 may continually control the power delivered to the heating element 25 and/or the heater wire 123 to maintain the target relative humidity.

[000332] In some configurations, the target relative humidity is the relative humidity of the flow gases in the conduit 122. The target relative humidity may be the relative humidity of the flow gases at a patient end of the conduit 122. In some configurations, the target relative humidity may be approximately 80%. In other configurations, the target relative humidity may be less than 80%. In other configurations, the target relative humidity may be approximately 60%. In other configurations, the target relative humidity is less than 60%. It should be appreciated that in some of these configurations, the percentage of the target relative humidity is an example and other target relative humidity may be suitable.

[000333] In some configurations, the target average particle size may be based on a desired distance of travel into the patient's respiratory tract. In some configurations, the desired distance of travel may be for dispersion in or around the patient's upper respiratory tract. In other configurations, the desired distance of travel may be for dispersion beyond the patient's upper respiratory tract. In other configurations, the desired distance of travel may be for dispersion in or around the patient's lower respiratory tract.

[000334] In some configurations, the target average particle size is smaller when the desired distance of travel is dispersion in or around the patient's upper respiratory tract than the target average particle size when the desired distance of travel is dispersion in or around the patient's lower respiratory tract. In some configurations, the target average particle size may be a mass median aerodynamic diameter (MMAD) of <1.0 micrometer. In other configurations, the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.5 and 1.0 micrometer. In other configurations, the target average particle size is a median aerodynamic diameter (MMAD) of <0.5 micrometer. In some configurations, the target average particle size may be a mass median aerodynamic diameter (MMAD) of between 0.1 and 0.5 micrometer. It should be appreciated that in some of these configurations, the mass median aerodynamic diameter (MMAD) of the target average particle size is an example and other diameters may be suitable.

[000335] In some configurations, the heating element 25 is a heating plate.

[000336] In some configurations, the port for the nebulizer 128 is located downstream from the flow generator 101. In other configurations, the port for the nebulizer 128 is located at the humidifier 112. In other configurations, the port for the nebulizer 128 is located at or towards an inlet or outlet of the humidifier 112. In other configurations, the port for the nebulizer 128 is located at or towards an outlet of the humidifier 112. In other configurations, the port for the nebulizer 128 is located upstream from an apparatus end of the conduit 122. In other configurations, the port for the nebulizer 128 is located at or towards an apparatus end of the conduit 122. It should be appreciated that in some of these configurations, the location of the port for the nebulizer 128 is an example and other locations for the port for the nebulizer 128 may be suitable. [000337] In some configurations, the port is configured to receive the nebulizer 128 indirectly. In other configurations the respiratory therapy apparatus 200 further comprises a mount or a connector configured to be connected to the port at one opening. The mount or connector may be for receiving the nebulizer 128 at another opening. It should be appreciated that in some of these configurations, the target relative humidity is an example and other target relative humidity may be suitable. In other configurations, the port may be configured to be connected to a nebulizer 128, the nebulizer 128 introducing the nebulized substance to the flow of gases.

[000338] In some configurations, the respiratory therapy apparatus 200 comprises a standard therapy mode and a nebulization therapy mode. The nebulization therapy mode may comprise of a target relative humidity lower than a target relative humidity in the standard therapy mode. The power delivered to the heater wire 123 in the nebulization therapy mode may be higher than the power delivered in the standard therapy mode.

[000339] In some configurations, the standard therapy mode may comprise of a target relative humidity of approximately 100% and the nebulization therapy mode comprises a target relative humidity less than 100%. In other configurations, the target relative humidity in the nebulization therapy mode is less than 80%. In other configurations, the target relative humidity in the nebulization therapy mode is less than 60%. It should be appreciated that in some of these configurations, the target relative humidity is an example and other target relative humidity may be suitable.

[000340] In some configurations, a user can manually adjust between the standard therapy mode and the nebulization therapy mode. A feature for manually adjusting target average particle size becomes available after entering nebulization therapy mode.

[000341] In some configurations, the apparatus is configured to automatically control power to the heater wire 123 to achieve a default target average particle size. [000342] In some configurations, the apparatus is configured to automatically control power to the heating element 25 to achieve a default target average particle size. The default target average particle size may be <1.0 micrometer.

[000343] In some configurations, the respiratory therapy apparatus 200 further comprises a user control interface. The user control interface comprises a user control interface element for adjusting the target average particle size. The user control interface may comprise of a user control interface element for adjusting a target distance of travel into the patient's respiratory tract. In other configurations, the user control interface may comprise of a user control interface element for selecting a standard therapy mode and a nebulization therapy mode. In other configurations, the user control interface comprises a touch screen interface. In other configurations, the user control interface comprises mechanical interface having a physical element being one or a combination of a slider, dial, buttons.

[000344] In some configurations, there is provided a respiratory therapy system 100 for delivering a flow of gases to a patient comprising: a blower 106, a humidifier 112 including a heating element 25, and a conduit 122 in fluid communication with the humidifier 112. The humidifier 112 is in fluid communication with the blower 106 and is configured to humidify the gases. The conduit 122 is configured to direct the flow gases from the humidifier 112 to a patient/user. The conduit 122 comprises a heater wire 123 in the conduit 122. The respiratory therapy system 100 further comprises a port fluidly coupled to the humidifier 112 and the conduit 122. The port is adapted to introduce nebulised substances into the flow of gases. The respiratory therapy system 100 further comprises a controller 113 operatively coupled to the heating element 25, heater wire 123 and blower 106. The controller 113 is configured to: adjust the speed of the blower 106 to provide a flow of gases at a target flow rate, adjust the power to the heating element 25 and/or heater wire 123, control the particle size of the nebulised substances to a target size range.

[000345] In some configurations, there is provided a respiratory therapy system 100 for delivering a flow of gases to a patient comprising: a blower 106, a humidification apparatus in fluid communication with the blower 106. The humidification apparatus is configured to adjust the humidity of the flow of gases. The respiratory therapy system 100 further comprises a gases path defined between the blower 106 and the patient. The gases path comprises the humidification apparatus and a port adapted to receive nebulised substance. The respiratory therapy system 100 further comprises a controller 113 operatively coupled to the blower 106 and the humidification apparatus. The controller 113 is configured to: adjust the speed of the blower 106 to provide the flow of gases at a set flow rate, adjust the humidity output of the humidification apparatus to control the particle size of the nebulised substance.

[000346] In some configurations, the humidification apparatus comprises a humidifier 112 having a heater plate.

[000347] In some configurations, the humidification apparatus comprises a conduit 122 having a heater wire 123.

[000348] In some configurations, the system comprises a nebulization therapy mode. In nebulization therapy mode the humidity of the flow of gases from the humidifier 112 may be reduced either for a set period of time or while the system is in nebulization therapy mode. In some configurations, in nebulization therapy mode the power supplied to the heater plate and/or the temperature set point of the heater plate is reduced to decrease the absolute humidity. In other configurations, the power supplied to the conduit 122 heater wire 123 increases to reduce the relative humidity.

[000349] In some configurations, in nebulization therapy mode, the humidification apparatus is configured to cause an alarm when the humidity of the flow of gases is greater than an allowable absolute or allowable relative humidity.

[000350] In some configurations, in nebulization therapy mode the flow rate range of the flow of gases is within a set flow rate range. In some configurations, the set flow rate range may be between approximately 30 L/min and 50 L/min.

[000351] In some configurations, when the nebulization therapy mode is activated, the controller 113 is configured to adjust the speed of the blower 106 to provide the flow rate range of the flow of gases within the set flow rate range. In other configurations, when the nebu lization therapy mode is activated and the flow rate of the flow of gases is higher than the set flow rate range, the controller 113 is configured to decrease the speed of the blower 106 to provide the flow rate range of the flow of gases within the set flow rate range. Optionally the speed of the blower 106 will decrease to provide the flow rate range of the flow of gases to within an upper region of the set flow rate range. In other configurations, when the nebulization therapy mode is activated and the flow rate of the flow of gases is lower than the set flow rate range, the controller 113 is configured to increase the speed of the blower 106 to provide the flow rate range of the flow of gases within the set flow rate range. Optionally the speed of the blower 106 will increase to provide the flow rate range of the flow of gases within a lower region of the set flow rate range.

[000352] In some configurations, the humidification apparatus is configured to cause an alarm when the nebulization therapy mode is activated and the flow of gases is higher or lower than the set flow rate range. The nebulization therapy mode may be activate for a set period of time. In other configurations, the humification apparatus is configured to cause an alarm when the period of time the nebuliser therapy mode is active is longer than the set period of time. When the nebuliser therapy mode is active, the patient or user defines the particle size range.

[000353] In some configurations, the respiratory apparatus is configured to modify the relative humidity and/or the absolute humidity to a specific range to control the particle size of the nebulized substance. The particle size of the nebulised substance may be controlled to or towards a specific size range by adjusting the relative humidity and/or absolute humidity.

[000354] In some configurations, the respiratory therapy system 100 is configured to provide high flow therapy. In other configurations, the respiratory therapy system 100 is configured to provide nasal high flow therapy with nebulised substances.

[000355] The respiratory therapy apparatus 200 may have any one or more of the features and/or functionality described herein.

[000356] The respiratory therapy apparatus 200 may be provided as a stand-alone device.

Alternatively, the respiratory therapy apparatus 200 may be provided as part of or used in a respiratory therapy system 100 having the respiratory therapy apparatus 200 and one or more of the conduit 122, patient interface, 124, nebulizer 128, or other component(s) described herein.

[000357] Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is to say, in the sense of "including, but not limited to."

[000358] Where, in the foregoing description reference has been made to integers or components having known equivalents thereof, those integers or components are herein incorporated as if individually set forth.

[000359] The disclosed methods, apparatus and systems may also be said broadly to comprise the parts, elements and features referred to or indicated in the disclosure, individually or collectively, in any or all combinations of two or more of said parts, elements or features.

[000360] Reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that that prior art forms part of the common general knowledge in the field of endeavour in any country in the world.

[000361] Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the disclosure as if it were individually recited herein. Additionally, each sub-range of values within ranges of values is incorporated into the disclosure as if it were individually recited herein.

[000362] Although the present disclosure has been described in terms of certain embodiments, other embodiments apparent to those of ordinary skill in the art also are within the scope of this disclosure. Thus, various changes and modifications may be made without departing from the spirit and scope of the disclosure. For instance, various components may be repositioned as desired. Moreover, not all of the features, aspects and advantages are necessarily required to practice the present disclosure. Accordingly, the scope of the present disclosure is intended to be defined only by the claims that follow.

Claims

1. A respiratory therapy system for delivering a flow of gases to a patient, comprising: a flow generator configured to generate the flow of gases; a conduit configured to deliver the flow of gases from the flow generator to the patient, the conduit comprising a lumen and a heater wire configured to heat the flow of gases in the conduit; a port configured to be in fluid communication with the conduit and for receiving a nebulized substance and introducing it to the flow of gases to the patient; and a controller configured to adjust power delivered to at least the heater wire to regulate an average particle size of the nebulized substance to or towards a target.

2. A respiratory therapy system according to the preceding claim, wherein the controller controls the power delivered to the heater wire to reach a target relative humidity of the flow of gases.

3. A respiratory therapy system according to any one of the preceding claims, wherein the controller continually controls the power delivered to the heater wire to maintain a target relative humidity of the flow of gases.

4. A respiratory therapy system according to any one of claims 2 or 3, wherein the target relative humidity is the relative humidity of the flow of gases in the conduit.

5. A respiratory therapy system according to any one of claims 2 to 4, wherein the target relative humidity is the relative humidity of the flow of gases at a patient end of the conduit.

6. A respiratory therapy system according to any one of claims 2 to 5, wherein the target relative humidity is approximately 80%.

7. A respiratory therapy system according to any one of claims 2 to 5, wherein the target relative humidity is less than 80%. . A respiratory therapy system according to the preceding claim, wherein the target relative humidity is approximately 60%. . A respiratory therapy system according to claim 7, wherein the target relative humidity is less than 60%. 0. A respiratory therapy system according to any one of the preceding claims, wherein the target average particle size is based on a desired distance of travel into the patient's respiratory tract. 1. A respiratory therapy system according to the preceding claim, wherein the desired distance of travel is for dispersion in or around the patient's upper respiratory tract. 2. A respiratory therapy system according to any one of claims 10 or 1 1 , wherein the desired distance of travel is for dispersion beyond the patient's upper respiratory tract. 3. A respiratory therapy system according to any one of claims 10 or 1 1 wherein the desired distance of travel is for dispersion in or around the patient's lower respiratory tract. 4. A respiratory therapy system according to any one of the preceding claims, wherein the target average particle size is relatively larger when the desired distance of travel is dispersion in or around the patient's upper respiratory tract than the target average particle size when the desired distance of travel is dispersion in or around the patient's lower respiratory tract. 5. A respiratory therapy system according to any one of the preceding claims, wherein the target average particle size is a mass median aerodynamic diameter (MMAD) of < 1.0 micrometer. 6. A respiratory therapy system according to the preceding claim, wherein the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.5 and 1.0 micrometer. 17. A respiratory therapy system according to claim 15, wherein the target average particle size is a median aerodynamic diameter (MMAD) of <0.5 micrometer.

18. A respiratory therapy system according to the preceding claim, wherein the target average particle size is a mass median aerodynamic diameter (MMAD) of between 0.1 and 0.5 micrometer.

19. A respiratory therapy system according to any one of the preceding claims, further comprising a humidifier, the humidifier comprising a heating element.

20. A respiratory therapy system according to the preceding claim, wherein the controller is configured to adjust power delivered to the heating element to regulate the average particle size of the nebulized substance to or towards a target.

21 . A respiratory therapy system according to any one of claims 19 or 20, wherein the controller controls both the power delivered to the heater wire and the power delivered to the heating element to achieve the target average particle size.

22. A respiratory therapy system according to the preceding claim, wherein the controller controls the power delivered to the heater wire independently from the power delivered to the heating element to regulate the average particle size.

23. A respiratory therapy system according to any one of claims 19 to 22, wherein the heating element is configured to heat a heating plate.

24. A respiratory therapy system according to any one of the preceding claims, wherein the port for the nebulizer is located downstream from the flow generator.

25. A respiratory therapy system according to any one of the preceding claims, wherein the port for the nebulizer is located at the humidifier.

26. A respiratory therapy system according to the preceding claim, wherein the port for the nebulizer is located at or towards an inlet or outlet of the humidifier. 27. A respiratory therapy system according to the preceding claim, wherein the port for the nebulizer is located at or towards an outlet of the humidifier.

28. A respiratory therapy system according to any one of the preceding claims, wherein the port for the nebulizer is located upstream from a device end of the conduit.

29. A respiratory therapy system according to any one of claims 1 to 27, wherein the port for the nebulizer is located at or towards a device end of the conduit.

30. A respiratory therapy system according to any one of the preceding claims, wherein the port is configured to receive the nebulizer indirectly.

31. A respiratory therapy system according to any one of the preceding claims, further comprising a connector configured to be connected to the port at one opening, and for receiving the nebulizer at another opening.

32. A respiratory therapy system according to any one of the preceding claims, further comprising a nebulizer configured to be connected at the port, the nebulizer introducing the nebulized substance to the flow of gases.

33. A respiratory therapy system according to any one of the preceding claims, wherein the system comprises a standard therapy mode and a nebulisation therapy mode.

34. A respiratory therapy system according to the preceding claim, wherein the nebulisation therapy mode comprises a target relative humidity lower than a target relative humidity in the standard therapy mode.

35. A respiratory therapy system according to any one of claims 33 or 34, wherein the power delivered to the heater wire in the nebulisation therapy mode is higher than the power delivered in the standard therapy mode.

36. A respiratory therapy system according to any one of claims 33 to 35, wherein the standard therapy mode comprises a target relative humidity of approximately 100% and the nebulisation therapy mode comprises a target relative humidity less than 100%.

37. A respiratory therapy system according to the preceding claim, wherein the target relative humidity in the nebulisation therapy mode is less than 80%.

38. A respiratory therapy system according to the preceding claim, wherein the target relative humidity in the nebulisation therapy mode is less than 60%.

39. A respiratory therapy system according to any one of claims 33 to 38, wherein a user can manually adjust between the standard therapy mode and the nebulisation therapy mode.

40. A respiratory therapy system according to any one of claims 33 to 39, wherein a feature for manually adjusting target average particle size becomes available after entering nebulisation therapy mode.

41. A respiratory therapy system according to any one of the preceding claims, wherein the system is configured to automatically control power delivered to the heater wire to achieve a default target average particle size of a nebulized substance being delivered to a patient via the flow of gases.

42. A respiratory therapy system according to any one of claims 19 to 41, wherein the system is configured to automatically control power delivered to the heating element to achieve a default target average particle size.

43. A respiratory therapy system according to any one of claims 41 or 42, wherein the default target average particle size is <1.0 micrometer.

44. A respiratory therapy system according to any one of the preceding claims, further comprising a user control interface. A respiratory therapy system according to the preceding claim, wherein the user control interface comprises a user control interface element for adjusting the target average particle size. A respiratory therapy system according to any one of claims 44 or 45, wherein the user control interface comprises a user control interface element for adjusting a target distance of travel into the patient's respiratory tract. A respiratory therapy system according to any one of claims 44 to 46, wherein the user control interface comprises a user control interface element for selecting a standard therapy mode and a nebulisation therapy mode. A respiratory therapy system according to any one of claims 44 to 47, wherein the user control interface comprises a touch screen interface. A respiratory therapy system according to any one of claims 44 to 48, wherein the user control interface comprises mechanical interface having a physical element being one or a combination of a slider, dial, buttons. A respiratory therapy system according to any one of the preceding claims, wherein the conduit comprises a length of greater than 0.5 meters. A respiratory therapy system according to the preceding claim, wherein the conduit comprises a length of greater than 1 meter. A respiratory therapy system according to the preceding claim, wherein the conduit comprises a length of greater than 1.5 meters.