A PATIENT INTERFACE AND A RESPIRATORY SUPPORT SYSTEM

A nasal cannula interface is provided for supplying a gases flow to a patient comprising: a nasal cannula defining at least a portion of a gases flow path and comprising a body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient, and one or more sensors configured to measure a parameter. The one or more sensors may comprise a pulse oximeter. The one or more sensors may be mounted on the nasal cannula body, or headgear to which the body is connector. The one or more sensors may be configured to be in contact with the face of the patient, and may be configured to be mounted in and/or substantially flush with, a cheek contacting portion of the interface.

FIELD OF THE DISCLOSURE

The present disclosure generally relates to patient interfaces and respiratory support systems for providing a breathable gases flow to patients, and more particularly to respiratory support systems with sensors on or near the patient interface.

BACKGROUND

When providing respiratory support to a patient, it can be beneficial to monitor one or more patient parameters during the course of the therapy. In order to measure these patient parameters one or more patient sensors is used, such as a pulse oximeter, which can be used to determine blood oxygen saturation and heart rate. These parameters can be used individually or in conjunction with further parameters in making an assessment of the patient's health. Additionally, these parameters can be used to adjust one or more control parameters of the respiratory support system being used to provide respiratory support to the patient. This adjustment can be done manually by a clinician, or automatically by a controller of the respiratory support system, such as through feedback control. The parameters being adjusted can include any one or more of flow rate, pressure, temperature, humidity, dew point, oxygen concentration, and/or oxygen saturation.

SUMMARY

The systems, methods and devices described herein have innovative aspects, no single one of which is indispensable or solely responsible for their desirable attributes. Without limiting the scope of the claims, some of the advantageous features will now be summarized.

Throughout, the term ‘respiratory support system’ in this specification means the combination of a respiratory support apparatus and any associated components used for providing respiratory support to a patient, such as a patient interface and/or one or more gases conduits and/or other components used to provide respiratory support to a patient. Components that may make up at least a part of the respiratory support apparatus can include any one or more of: a flow generator, a controller, a humidifier, a graphical user interface, a flow control valve.

Throughout, the term ‘circuit’ in this specification means the entire breathable gases inspiratory pathway to the patient from a gases supply, and may also include the expiratory gases path away from the patient to a gases supply. The circuit at a minimum therefore includes the inspiratory gases pathway (including all the components) from the gases supply to the patient interface. The interface itself e.g. mask or cannula, is separate from the gases pathway and not part of the ‘circuit’.

Throughout this specification, a ‘gases conduit’ is any passageway configured to transport a breathable gases flow.

Throughout this specification, the terms ‘clinician’, ‘patient’, and ‘user’ may be used to refer to individuals who may interact with the respiratory support apparatus. The term ‘patient’ as used in this specification means the individual who is receiving therapy (e.g. a therapeutic gases flow) from the respiratory support system, and in particular is the individual who is wearing the patient interface. The term ‘clinician’ as used in this specification means an individual such as a nurse or a doctor who is not receiving therapy from the respiratory support system, but might adjust the settings of the respiratory support apparatus, aid in setting up the respiratory support system, and/or help to affix the patient interface to the patient, or prescribe therapy, among other tasks. The term ‘user’ as used in this specification means an individual who may adjust the settings of the respiratory support apparatus, aid in setting up the respiratory support system, and/or help to affix the patient interface to the patient, among other tasks. Depending on the situation, the user may be a clinician or the patient themselves. For example, in a hospital scenario, a clinician is likely setup the system for the patient, and as such the term ‘user’ likely refers to the clinician. For scenarios in which the ‘user’ is adjusting the operating parameters of the respiratory support apparatus but not necessarily interacting with the patient, the user may be a biomedical engineer or a maintenance engineer or a technician. Conversely, in a scenario in which the patient is using the respiratory support system at home, the patient may set the system themselves, and as such the term ‘user’ likely refers to the patient.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, andone or more sensors configured to measure a parameter,wherein the one or more sensors are mounted (i.e. positioned) on any one or more of:a) the patient interface;b) headgear configured to mount the patient interface on the patient's head;c) a headgear connector configured to connect the headgear to the patient interface;d) a gas delivery conduit configured to deliver breathable gases to the patient.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, anda frame on which the body is permanently or removably mounted, the frame configured to connect to headgear to mount the patient interface on the patient's head;one or more sensors configured to measure a parameter,wherein the one or more sensors are mounted on the patient interface and/or the frame and/or the headgear.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, andlateral arms extending laterally outwardly from the body and configured to connect to headgear to mount the patient interface on the patient's head;one or more sensors configured to measure a parameter,wherein the one or more sensors are mounted on the patient interface and/or the lateral arms and/or the headgear.

The one or more sensors may be removably mounted (i.e. can be removed from the patient interface and re-positioned) into any one or more of:a) the patient interface;b) headgear configured to mount the patient interface on the patient's head;c) a headgear connector configured to connect the headgear to the patient interface;d) a gas delivery conduit configured to deliver breathable gases to the patient.

The one or more sensors being removable can be advantageous because the sensors can be removed, cleaned and mounted into another interface. This allows the sensors to be re-used between different patients.

Alternatively the one or more sensors may be integrated into one or more of:a) the patient interface;b) headgear configured to mount the patient interface on the patient's head;c) a headgear connector configured to connect the headgear to the patient interface;d) a gas delivery conduit configured to deliver breathable gases to the patient.

The one or more sensors may be integrated such that they cannot be removed. In this integrated arrangement the one or more sensors may be disposable.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, andone or more sensors configured to measure a parameter,wherein the body further comprises a top surface and a rear surface, the rear surface being adjacent the patient in use of the patient interface; whereinan outer surface of the one or more sensors is flush with the top surface or the rear surface.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, andone or more sensors configured to measure a parameter,wherein the one or more sensors are embedded below an outer surface of the body of the patient interface.

At least one of the one or more sensors may be a patient sensor, and the parameter may be a physiological parameter of the patient.

The parameter may be a measure of blood oxygenation of the patient.

The patient interface may sealingly engage with the orifice of the patient.

The patient interface may comprise a mask.

The mask may be a nasal mask.

The mask may be an oral mask.

The mask may be a nasal mask.

The mask may be a full face mask.

The mask may comprise a cushion.

The one or more sensors may be flush with an outer surface of the cushion.

The patient interface may comprise a nasal pillows interface.

The patient interface may comprise a tracheostomy interface.

The patient interface may further comprise a head securement assembly.

The head securement assembly may comprise one or more straps.

The head securement assembly may comprise one or more facial pads.

The or each facial pad may comprise an adhesive surface to adhere to the patient's skin.

The or each facial pad may comprise two distinct patches.

The two distinct patches may be removably coupled.

The one or more sensors may be a pulse oximeter.

The pulse oximeter may be a reflectance type pulse oximeter.

The one or more sensors may be arranged to contact the patient's columella whilst the patient interface is in use.

The patient interface may further comprise:a gases inlet conduit for receiving the gases flow from a flow source, the gases inlet conduit defining at least a portion of a gases flow path; andan interface connector for receiving the gases flow from the gases inlet conduit and directing the gases flow towards the patient.

The patient interface may further comprise a set of wires, wherein the gases inlet conduit further comprises a patient end, and a distal end, andwherein the patient end is connected to the interface connector,the distal end comprises an interface inlet, the interface inlet comprising a set of electrical contacts, andthe set of wires of the patient interface provides electrical communication between the one or more sensors and the set of electrical contacts of the interface inlet.

The set of electrical contacts of the interface inlet may comprise a planar surface, and the planar surface may be substantially perpendicular to a longitudinal axis of a lumen of the interface inlet.

The set of electrical contacts of the interface inlet may comprise a pin and/or a socket of a pin and socket electrical connector, and a longitudinal axis of the pin and/or socket may be substantially parallel to a longitudinal axis of a lumen of the interface inlet.

The set of electrical contacts of the interface inlet may be in a fixed position relative to the remainder of the interface inlet.

The patient interface may further comprise a mesh layer surrounding the outer surface of at least a portion of the body of the patient interface or the gases inlet conduit, wherein the mesh may comprise a plurality of interwoven filaments, and at least a portion of the set of wires of the patient interface may be interwoven with the filaments of the mesh layer.

At least a portion of the set of wires of the patient interface may be embedded into at least a portion of the body of the patient interface, the interface connector of the patient interface, or the gases inlet conduit.

At least a portion of the set of wires of the patient interface may be located on an outer surface of at least a portion of the body of the patient interface, the interface connector of the patient interface, or the gases inlet conduit.

At least a portion of the set of wires of the patient interface may be located on an inner surface of at least a portion of the body of the patient interface, the interface connector of the patient interface, or the gases inlet conduit.

According to an aspect of this disclosure there is provided a respiratory support system for generating a gases flow comprising:a respiratory support apparatus comprising:a flow generator,a respiratory support apparatus outlet, anda controller,an inspiratory conduit comprising:a patient end having an inspiratory conduit outlet, andan apparatus end having an inspiratory conduit inlet,the patient interface of any of the preceding or subsequent statements;wherein the respiratory support apparatus outlet is configured to form a pneumatic and electrical connection with the inspiratory conduit inlet,wherein the respiratory support apparatus outlet is in electrical communication with the controller, andthe controller is configured to supply power to and receive data from the one or more sensors.

The flow generator may be a blower.

The respiratory support system may further comprise a humidifier for adding heat and/or humidity to the gases flow.

The respiratory support system may further comprise an ambient air inlet.

The respiratory support system may further comprise at least one supplemental gas inlet for receiving a flow of supplemental gases.

The respiratory support system may further comprise a valve to regulate the flow of supplemental gases through the at least one supplemental gas inlets.

The valve may be a proportional valve.

The at least one supplemental gas inlet may be an oxygen inlet.

The respiratory support apparatus may comprise at least one gases composition sensor to measure the composition of the gases flow.

The at least one gases composition sensor may comprise an ultrasonic sensor system.

The controller may be configured to:receive a measure of the composition of the gases flow from the at least one gases composition sensor;compare the measure of the composition of the gases flow with a target gases composition; andadjust the position of the valve based at least in part on the comparison between the two values.

The target gases composition may be set by a user.

The controller may be configured to:receive a measure of the parameter from the one or more sensors;compare the measure of the parameter with a target value for the parameter; and adjust the target gases composition based at least in part on the comparison between the measure and the target value.

The target parameter may be set by a user.

The measure of the parameter may be used by the controller to determine when the patient is using the patient interface.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:one or more sensors configured to be placed on the patient's skin and configured to measure at least one parameter, anda body configured to engage an orifice of the patient and direct the gases flow to said orifice,wherein the one or more sensors are moveable relative to the body of the patient interface.

The patient interface may further comprise a gases inlet conduit for receiving the gases flow from a flow source, the gases inlet conduit defining at least a portion of a gases flow path and comprising a patient end and a distal end.

The patient interface may further comprise a first set of wires.

The patient interface may further comprise an interface connector for receiving the gases flow from the gases inlet conduit and directing the gases flow towards the patient.

The patient end may be connected to the interface connector.

The distal end may comprise an interface inlet, the interface inlet comprising a set of electrical contacts.

The first set of wires of the patient interface may provide electrical communication between the one or more sensors and the set of electrical contacts of the interface inlet.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a gases inlet conduit for receiving the gases flow from a flow source, the gases inlet conduit defining at least a portion of a gases flow path and comprising a patient end and a distal end,a first set of wires,one or more sensors configured to be placed on the patient's skin and configured to measure at least one parameter,a body, andan interface connector for receiving the gases flow from the gases inlet conduit, and wherein the patient end is connected to the interface connector,the distal end comprises an interface inlet, the interface inlet comprising a set of electrical contacts, andthe first set of wires of the patient interface provides electrical communication between the one or more sensors and the set of electrical contacts of the interface inlet.

The patient interface may sealingly engage with the orifice of the patient.

The patient interface may comprise a mask.

The mask may be a nasal mask.

The mask may be an oral mask.

The mask may be a nasal mask.

The mask may be a full face mask.

The mask may comprise a cushion.

The one or more sensors may be flush with an outer surface of the cushion.

The patient interface may comprise a nasal pillows interface.

The patient interface may comprise a tracheostomy interface.

At least one of the one or more sensors may be a patient sensor, and the parameter may be a physiological parameter of the patient.

The physiological parameter may be a measure of blood oxygenation of the patient.

At least one of the one or more sensors may be a pulse oximeter.

The pulse oximeter may be a reflectance type pulse oximeter.

The pulse oximeter may be a transmissive pulse oximeter.

The patient interface may further comprise a head securement assembly.

The head securement assembly comprise one or more straps.

The sensors may be moveable relative to the body of the patient interface.

The patient interface may further comprise a sensor arm, wherein the one or more sensors may be located on the sensor arm.

The sensor arm may be rigid such that it cannot be easily bent by a user.

The sensor arm may be deformable such that it can be easily bent by a user. The sensor arm may be non-elastically deformable such that the sensor arm may remain in a bent condition, once deformed by the user. The sensor arm may be resiliently deformable.

A surface of the sensor arm may comprise an adhesive such that the surface is capable of adhering to the patient's skin.

A length of the sensor arm may be adjustable.

The length of sensor arm may be adjustable through telescopic motion.

The head securement assembly may further comprise a sensor mount connected to one of the straps, wherein the sensor arm projects from the sensor mount.

The sensor mount may be moveably connected to one of the straps.

The sensor mount may be slidably connected to one of the straps.

The sensor mount may be removably connected to one of the straps.

The patient interface may further comprise a sensor mount connected to one the gases inlet conduit, wherein the sensor arm projects from the sensor mount.

The sensor mount may be moveably connected to the gases inlet conduit.

The sensor mount may be slidably connected to the gases inlet conduit.

The sensor mount may be removably connected to the gases inlet conduit.

The sensor arm may be moveable relative to the sensor mount.

The sensor arm may be slidably mounted to the sensor mount.

The sensor arm may be slidably mounted to the sensor mount so as to be able to slide in a direction parallel to the length of the strap or gases inlet conduit to which the sensor mount is connected.

The sensor arm may be slidably mounted to the sensor mount so as to be able to slide in a direction transverse to the length of the strap or gases inlet conduit which the sensor mount is connected to.

The sensor arm may be configured to rotate about an axis at which it connects to the sensor mount.

The patient interface may further comprise a sensor clip configured to clip onto the patient, wherein the one or more sensors may be located on the sensor clip.

The sensor clip may be configured to clip onto the patient's ear.

The gases inlet conduit may be substantially rigid.

The gases inlet conduit may be substantially flexible.

The gases inlet conduit may be integrally formed with the patient interface.

The gases inlet conduit may be releasably connected to the patient interface.

The set of electrical contacts of the interface inlet may comprise a planar surface, andthe planar surface is substantially perpendicular to a longitudinal axis of a lumen of the interface inlet.

The set of electrical contacts of the interface inlet may comprise a pin and/or a socket of a pin and socket electrical connector, anda longitudinal axis of the pin and/or socket may be substantially parallel to a longitudinal axis of a lumen of the interface inlet.

The set of electrical contacts of the interface inlet may be in fixed position relative to the remainder of the interface inlet.

The patient interface may further comprise a mesh layer surrounding the outer surface of at least a portion of the patient interface or the gases inlet conduit,wherein the mesh may comprise a plurality of interwoven filaments, andat least a portion of the first set of wires of the patient interface may be interwoven with the filaments of the mesh layer.

At least a portion of the first set of wires of the patient interface may be embedded into at least a portion of the body of the patient interface, the interface connector of the patient interface, or the gases inlet conduit.

At least a portion of the first set of wires of the patient interface may be located on an outer surface of at least a portion of the body of the patient interface, the interface connector of the patient interface, or the gases inlet conduit.

At least a portion of the first set of wires of the patient interface may be located on an inner surface of at least a portion of the body of the patient interface, the interface connector of the patient interface, or the gases inlet conduit.

The patient interface may further comprise:a wire coil, anda second set of wires extending from the sensor to the wire coil, whereinthe second set of wires can be retracted into the wire coil,the wire coil is connected to the first set of wires, andat least one of the one or more sensors or the sensor is located at the end of the second set of wires.

The second set of wires may retract into the wire coil automatically.

The second set of wires may retract into the wire coil upon user actuation of a button, switch, or lever.

The wire coil may be mounted to one of the straps.

The wire coil may be removably mounted to one of the straps.

The wire coil may be mounted to the gas inlet conduit.

The wire coil may be removably mounted to the gas inlet conduit.

According to an aspect of this disclosure there is provided a respiratory support system for generating a gases flow comprising:a respiratory support apparatus comprisinga flow generator,a respiratory support apparatus outlet, anda controller,an inspiratory conduit comprisinga patient end having an inspiratory conduit outlet, andan apparatus end having an inspiratory conduit inlet,the patient interface of any of the preceding statements, andwherein the respiratory support apparatus outlet is configured to form a pneumatic and electrical connection with the inspiratory conduit inlet,wherein the respiratory support apparatus outlet is in electrical communication with the controller, andthe controller is configured to supply power to and receive data from the one or more sensors.

The flow generator may be a blower.

The respiratory support system may further comprise a humidifier for adding heat and/or humidity to the gases flow.

The respiratory support system may further comprise an ambient air inlet.

The respiratory support system may further comprise one or more supplemental gases inlets for receiving a flow of supplemental gases.

At least one of the one or more supplemental gases inlets may be an oxygen inlet.

The respiratory support system may further comprise a valve to regulate the flow of supplemental gases through the at least one of the one or more supplemental gases inlets.

The valve may be a proportional valve.

The respiratory support apparatus may comprise one or more gases composition sensors to measure the composition of the gases flow.

The one or more gases composition sensors may comprise an ultrasonic sensor system.

The controller may be configured to:receive a measure of the composition of the gases flow from the one or more gases composition sensors,compare the measure of the composition of the gases flow with a target composition, andadjust the position of the valve based at least in part on the difference between the two values.

The target gases composition may be set by a user.

The controller may be configured to:receive a measure of the parameter from the one or more sensors,compare the measure of the parameter with a target value for the parameter, andadjust the target gases composition based at least in part on the difference between the measure and target value.

The target value for the parameter may be set by a user.

The measure of the parameter may be used by the controller to determine when the patient is using the patient interface.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a patient interface defining at least a portion of a gases flow path and comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, andone or more sensors configured to measure a parameter,wherein the sensor is configured to contact the nose of the patient when the patient interface is in use.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a patient interface defining at least a portion of a gases flow path and comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, andone or more sensors configured to measure a parameter,wherein the sensor is configured to contact the upper lip of the patient when the patient interface is in use.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a patient interface defining at least a portion of a gases flow path and comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, andone or more sensors configured to measure a parameter,wherein the sensor is configured to contact the lower lip of the patient when the patient interface is in use.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a patient interface defining at least a portion of a gases flow path and comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, andone or more sensors configured to measure a parameter,wherein the sensor is configured to contact the mouth of the patient when the patient interface is in use.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a patient interface defining at least a portion of a gases flow path and comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, andone or more sensors configured to measure a parameter,wherein the sensor is configured to contact the cheek of the patient when the patient interface is in use.

According to an aspect of this disclosure there is provided a patient interface for supplying a gases flow to a patient comprising:a patient interface defining at least a portion of a gases flow path and comprising:a body configured to engage with an orifice of the patient and direct the gases flow to said orifice, andone or more sensors configured to measure a parameter,wherein the sensor is configured to contact the neck of the patient when the patient interface is in use.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:a nasal cannula defining at least a portion of a gases flow path and comprising:a body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient, andone or more sensors configured to measure a parameter,wherein the body further comprises a top surface and a rear surface, the rear surface being adjacent the patient in use of the nasal cannula interface; wherein an outer surface of the one or more sensors is flush with the top surface or the rear surface.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:a nasal cannula defining at least a portion of a gases flow path and comprising:a body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient, andone or more sensors configured to measure a parameter,wherein the one or more sensors are embedded below an outer surface of the body of the nasal cannula.

At least one of the one or more sensors may be a patient sensor, and the parameter may be a physiological parameter of the patient.

The parameter may be a measure of blood oxygenation of the patient.

The at least one prong may be configured to be received in one or more nares of the patient.

One or more of the at least one prong may be configured to form a seal with one of the nares of the patient.

One or more of the at least one prong may be configured be received in one of the nares of the patient in an unsealed manner.

The nasal cannula may further comprise a head securement assembly.

The head securement assembly may comprise one or more straps.

The head securement assembly may comprise one or more facial pads.

The or each facial pad may comprise an adhesive surface to adhere to the patient's skin.

The or each facial pad may comprise two distinct patches.

The two distinct patches may be removably coupled.

The nasal cannula may further comprise a pair of side arms.

The pair of side arms may be integral with the body of the nasal cannula.

The head securement assembly may be connected to the side arms.

The facial pads may be located on the side arms.

The outer surface of the patient sensor may be flush with the top surface, and the top surface may be a patient contacting surface, or the outer surface of the patient sensor may be flush with the rear surface and the rear surface may be a patient contacting surface.

The one or more sensors may be a pulse oximeter.

The pulse oximeter may be a reflectance type pulse oximeter.

The nasal cannula may further comprise a second prong extending from the base portion.

The one or more sensors may be located between the two prongs.

The at least one prong may extend from the top surface of the body of the nasal cannula, and the one or more sensors may be located on said top surface.

The one or more sensors may be arranged to contact the patient's columella whilst the nasal cannula interface is in use.

The at least one prong may extend from a top surface of the body of the nasal cannula, and the one or more sensors may be located on a surface of the body that is adjacent to said top surface.

The one or more sensors may be positioned on the body of the nasal cannula so as to contact the patient's upper lip whilst the nasal cannula interface is in use.

The nasal cannula interface may further comprise:a gases inlet conduit for receiving the gases flow from a flow source, the gases inlet conduit defining at least a portion of a gases flow path; andan interface connector for receiving the gases flow from the gases inlet conduit and directing the gases flow towards the at least one prong.

The nasal cannula interface may further comprise a set of wires, wherein the gases inlet conduit further comprises a patient end, and a distal end, andwherein the patient end is connected to the interface connector,the distal end comprises an interface inlet, the interface inlet comprising a set of electrical contacts, andthe set of wires of the nasal cannula interface provides electrical communication between the one or more sensors and the set of electrical contacts of the interface inlet.

The set of electrical contacts of the interface inlet may comprise a planar surface, and the planar surface may be substantially perpendicular to a longitudinal axis of a lumen of the interface inlet.

The set of electrical contacts of the interface inlet may comprise a pin and/or a socket of a pin and socket electrical connector, and a longitudinal axis of the pin and/or socket may be substantially parallel to a longitudinal axis of a lumen of the interface inlet.

The set of electrical contacts of the interface inlet may be in a fixed position relative to the remainder of the interface inlet.

The nasal cannula interface may further comprise a mesh layer surrounding the outer surface of at least a portion of the nasal cannula or the gases inlet conduit,wherein the mesh may comprise a plurality of interwoven filaments, and at least a portion of the set of wires of the nasal cannula interface may be interwoven with the filaments of the mesh layer.

At least a portion of the set of wires of the nasal cannula interface may be embedded into at least a portion of the body of the nasal cannula, the interface connector of the nasal cannula, or the gases inlet conduit.

At least a portion of the set of wires of the nasal cannula interface may be located on an outer surface of at least a portion of the body of the nasal cannula, the interface connector of the nasal cannula, or the gases inlet conduit.

At least a portion of the set of wires of the nasal cannula interface may be located on an inner surface of at least a portion of the body of the nasal cannula, the interface connector of the nasal cannula, or the gases inlet conduit.

According to an aspect of this disclosure there is provided a respiratory support system for generating a gases flow comprising:a respiratory support apparatus comprising:a flow generator,a respiratory support apparatus outlet, anda controller,an inspiratory conduit comprising:a patient end having an inspiratory conduit outlet, andan apparatus end having an inspiratory conduit inlet,the nasal cannula interface of any of the preceding statements;wherein the respiratory support apparatus outlet is configured to form a pneumatic and electrical connection with the inspiratory conduit inlet,wherein the respiratory support apparatus outlet is in electrical communication with the controller, andthe controller is configured to supply power to and receive data from the one or more sensors.

The flow generator may be a blower.

The respiratory support system may further comprise a humidifier for adding heat and/or humidity to the gases flow.

The respiratory support system may further comprise an ambient air inlet.

The respiratory support system may further comprise at least one supplemental gas inlet for receiving a flow of supplemental gases.

The respiratory support system may further comprise a valve to regulate the flow of supplemental gases through the at least one supplemental gas inlets.

The valve may be a proportional valve.

The at least one supplemental gas inlet may be an oxygen inlet.

The respiratory support apparatus may comprise at least one gases composition sensor to measure the composition of the gases flow.

The at least one gases composition sensor may comprise an ultrasonic sensor system.

The controller may be configured to:receive a measure of the composition of the gases flow from the at least one gases composition sensor,compare the measure of the composition of the gases flow with a target gases composition, andadjust the position of the valve based at least in part on the comparison between the two values.

The target gases composition may be set by a user.

The controller may be configured to:receive a measure of the parameter from the one or more sensors,compare the measure of the parameter with a target value for the parameter, andadjust the target gases composition based at least in part on the comparison between the measure and the target value.

The target parameter may be set by a user.

The measure of the parameter may be used by the controller to determine when the patient is using the nasal cannula interface.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:one or more sensors configured to be placed on the patient's skin and configured to measure at least one parameter, anda nasal cannula defining at least a portion of a gases flow path and comprisinga body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient,wherein the one or more sensors are moveable relative to the body of the nasal cannula.

The nasal cannula interface may further comprise a gases inlet conduit for receiving the gases flow from a flow source, the gases inlet conduit defining at least a portion of a gases flow path and comprising a patient end and a distal end.

The nasal cannula interface may further comprise a first set of wires.

The nasal cannula may further comprise an interface connector for receiving the gases flow from the gases inlet conduit and directing the gases flow towards the at least one prong.

The patient end may be connected to the interface connector.

The distal end may comprise an interface inlet, the interface inlet comprising a set of electrical contacts.

The first set of wires of the nasal cannula interface may provide electrical communication between the one or more sensors and the set of electrical contacts of the interface inlet.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:a gases inlet conduit for receiving the gases flow from a flow source, the gases inlet conduit defining at least a portion of a gases flow path and comprising a patient end and a distal end,a first set of wires,one or more sensors configured to be placed on the patient's skin and configured to measure at least one parameter, anda nasal cannula defining at least a portion of a gases flow path and comprisinga body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient, andan interface connector for receiving the gases flow from the gases inlet conduit and directing the gases flow towards the at least one prong, andwherein the patient end is connected to the interface connector,the distal end comprises an interface inlet, the interface inlet comprising a set of electrical contacts, andthe first set of wires of the nasal cannula interface provides electrical communication between the one or more sensors and the set of electrical contacts of the interface inlet.

The at least one prong may be configured to be received in one or more nares of the patient.

The at least one prong may be configured to form a seal with one of the nares of the patient.

The at least one prong may be configured to be received in one of the nares of the patient in an unsealed manner.

The nasal cannula interface may further comprise a second prong extending from the base portion.

At least one of the one or more sensors may be a patient sensor, and the parameter may be a physiological parameter of the patient.

The physiological parameter may be a measure of blood oxygenation of the patient.

At least one of the one or more sensors may be a pulse oximeter.

The pulse oximeter may be a reflectance type pulse oximeter.

The pulse oximeter may be a transmissive pulse oximeter.

The body of the nasal cannula further comprise a pair of side arms.

The nasal cannula interface may further comprise a head securement assembly.

The head securement assembly may be connected to the side arms.

The head securement assembly comprise one or more straps.

The sensors may be moveable relative to the body of the nasal cannula interface.

The nasal cannula interface may further comprise a sensor arm, wherein the one or more sensors may be located on the sensor arm.

The sensor arm may be rigid such that it cannot be easily bent by a user.

The sensor arm may be resiliently deformable such that it can be easily bent by a user.

A surface of the sensor arm may comprise an adhesive such that the surface is capable of adhering to the patient's skin.

A length of the sensor arm may be adjustable.

The length of sensor arm may be adjustable through telescopic motion.

The head securement assembly may further comprise a sensor mount connected to one of the straps, wherein the sensor arm projects from the sensor mount.

The sensor mount may be moveably connected to one of the straps.

The sensor mount may be slidably connected to one of the straps.

The sensor mount may be removably connected to one of the straps.

The nasal cannula interface may further comprise a sensor mount connected to one the gases inlet conduit, wherein the sensor arm projects from the sensor mount.

The sensor mount may be moveably connected to the gases inlet conduit.

The sensor mount may be slidably connected to the gases inlet conduit.

The sensor mount may be removably connected to the gases inlet conduit.

The sensor arm may be moveable relative to the sensor mount.

The sensor arm may be slidably mounted to the sensor mount.

The sensor arm may be slidably mounted to the sensor mount so as to be able to slide in a direction parallel to the length of the strap or gases inlet conduit to which the sensor mount is connected.

The sensor arm may be slidably mounted to the sensor mount so as to be able to slide in a direction transverse to the length of the strap or gases inlet conduit which the sensor mount is connected to.

The sensor arm may be configured to rotate about an axis at which it connects to the sensor mount.

The nasal cannula interface may further comprise a sensor clip configured to clip onto the patient, wherein the one or more sensors may be located on the sensor clip.

The sensor clip may be configured to clip onto the patient's ear.

The gases inlet conduit may be substantially rigid.

The gases inlet conduit may be substantially flexible.

The gases inlet conduit may be integrally formed with the nasal cannula.

The gases inlet conduit may be releasably connected to the nasal cannula.

The set of electrical contacts of the interface inlet may comprise a planar surface, andthe planar surface is substantially perpendicular to a longitudinal axis of a lumen of the interface inlet.

The set of electrical contacts of the interface inlet may comprise a pin and/or a socket of a pin and socket electrical connector, anda longitudinal axis of the pin and/or socket may be substantially parallel to a longitudinal axis of a lumen of the interface inlet.

The set of electrical contacts of the interface inlet may be in fixed position relative to the remainder of the interface inlet.

The nasal cannula interface may further comprise a mesh layer surrounding the outer surface of at least a portion of the nasal cannula or the gases inlet conduit,wherein the mesh may comprise a plurality of interwoven filaments, andat least a portion of the first set of wires of the nasal cannula interface may be interwoven with the filaments of the mesh layer.

At least a portion of the first set of wires of the nasal cannula interface may be embedded into at least a portion of the body of the nasal cannula, the interface connector of the nasal cannula, or the gases inlet conduit.

At least a portion of the first set of wires of the nasal cannula interface may be located on an outer surface of at least a portion of the body of the nasal cannula, the interface connector of the nasal cannula, or the gases inlet conduit.

At least a portion of the first set of wires of the nasal cannula interface may be located on an inner surface of at least a portion of the body of the nasal cannula, the interface connector of the nasal cannula, or the gases inlet conduit.

The nasal cannula interface may further comprise:a wire coil, anda second set of wires extending from the sensor to the wire coil, whereinthe second set of wires can be retracted into the wire coil,the wire coil is connected to the first set of wires, andat least one of the one or more sensors or the sensor is located at the end of the second set of wires.

The second set of wires may retract into the wire coil automatically.

The second set of wires may retract into the wire coil upon user actuation of a button, switch, or lever.

The wire coil may be mounted to one of the straps.

The wire coil may be removably mounted to one of the straps.

The wire coil may be mounted to the gas inlet conduit.

The wire coil may be removably mounted to the gas inlet conduit.

The nasal cannula interface may be configured such that the one or more sensor(s) are connected to one or more sensor wires via an inductive coupling. For example, the one or more sensor(s) may be configured to be connected to one or more sensor wires in a gases delivery conduit via the inductive coupling. Such a coupling can avoid the need for a physical electrical connector and exposed electrical contacts.

According to another aspect of this disclosure there is provided headgear for a patient interface comprisinga strap forming a part of the headgear for assisting in retaining or stabilising of a patient interface upon a user,a first connector at a first end portion of the strap for connecting the strap to the patient interface, anda first cheek engaging member adapted to encapsulate the first connector and having a surface region adapted to locate between the user's cheek and the connector to minimise direct contact of the connector with the user's skin in use;wherein one or more sensors are configured to be placed on or adjacent the patient's skin and configured to measure at least one parameter; the one or more sensors being mounted on the first cheek engaging member.

The headgear may further comprise a second connector at a second opposing end portion of the strap for connecting the strap to the patient interface, and a second cheek engaging member configured to encapsulate the second connector and having a surface region adapted to locate between the user's other cheek to minimise direct contact of the connector with the user's skin in use.

Each cheek engaging member may be configured to removably couple about the respective connector.

The surface region of each cheek engaging member may comprise a material that is substantially softer than a material of the respective connector.

The surface region of each cheek engaging member may comprise a relatively higher frictional surface material than the respective connector, to assist with retaining or stabilising of a patient interface upon the face of a user.

The material may be a thermoplastic elastomer.

The surface region of each cheek engaging member may be a surface of wider surface area at an end of the respective cheek engaging member more adjacent to the patient interface than a surface area of an opposing end of the cheek member more distant from the patient interface.

The surface region of each cheek engaging members may taper from a relatively wider end to a relatively lesser end.

Each cheek engaging member may be a sleeve configured to receivably retain the respective connector therein.

The sleeve may be configured to removably couple about the respective connector.

The connector may be adapted to extend through a passage in the sleeve.

The sensor may be connected to one or more sensor wires, the one or more sensor wires extending through the passage in the sleeve.

Each connector may be substantially housed by the respective sleeve in a region adapted to locate adjacent the user's cheek in use.

Each sleeve may be curved along at least a portion of the length of the sleeve to complement the contour of the respective cheek.

Each connector may be curved along at least a portion of the length of the connector adapted to locate adjacent the respective cheek.

The connector may be pre-formed with a curved profile.

Each sleeve may be pre-formed with a curved profile.

Each sleeve may be curved upon encapsulating the respective connector.

Each connector comprises a clip for releasably connecting with the patient interface.

Each connector may be frictionally or mechanically engaged with the respective cheek engaging member once in-situ.

The one or more sensor(s) may be mounted on the sleeve.

The one or more sensor(s) may be removably mounted on the cheek member.

An outer surface of the one or more sensors may be flush with the surface region of the cheek member.

According to an aspect of this disclosure there is provided a respiratory support system for generating a gases flow comprising:a respiratory support apparatus comprisinga flow generator,a respiratory support apparatus outlet, anda controller,an inspiratory conduit comprisinga patient end having an inspiratory conduit outlet, andan apparatus end having an inspiratory conduit inlet,the nasal cannula interface or headgear of any of the preceding statements, and wherein the respiratory support apparatus outlet is configured to form a pneumatic and electrical connection with the inspiratory conduit inlet,wherein the respiratory support apparatus outlet is in electrical communication with the controller, andthe controller is configured to supply power to and receive data from the one or more sensors.

The flow generator may be a blower.

The respiratory support system may further comprise a humidifier for adding heat and/or humidity to the gases flow.

The respiratory support system may further comprise an ambient air inlet.

The respiratory support system may further comprise one or more supplemental gases inlets for receiving a flow of supplemental gases.

At least one of the one or more supplemental gases inlets may be an oxygen inlet.

The respiratory support system may further comprise a valve to regulate the flow of supplemental gases through the at least one of the one or more supplemental gases inlets.

The valve may be a proportional valve.

The respiratory support apparatus may comprise one or more gases composition sensors to measure the composition of the gases flow.

The one or more gases composition sensors may comprise an ultrasonic sensor system.

The controller may be configured to:receive a measure of the composition of the gases flow from the one or more gases composition sensors;compare the measure of the composition of the gases flow with a target composition; andadjust the position of the valve based at least in part on the difference between the two values.

The target gases composition may be set by a user.

The controller may be configured to:receive a measure of the parameter from the one or more sensors;compare the measure of the parameter with a target value for the parameter; and adjust the target gases composition based at least in part on the difference between the measure and target value.

The target value for the parameter may be set by a user.

The measure of the parameter may be used by the controller to determine when the patient is using the nasal cannula interface.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:a nasal cannula defining at least a portion of a gases flow path and comprising a body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient, the body comprising a lateral mount; and
headgear according to any one of the above statements; wherein the first connector of the headgear is connected to the lateral mount of the body.

The body may comprise a recess positioned between a pair of prongs, wherein the prongs extend from the body. The sensor may be located in the recess, between the prongs.

The nasal cannula interface may comprise a manifold part received within an opening in the body (i.e. face mount part), wherein the manifold part comprises a dip, wherein the dip in the manifold portion aligns with the recessed in the body when the manifold is inserted into the body.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising a nasal cannula defining at least a portion of a gases flow path and comprising:a body having a base portion and pair of prongs extending from the base portion, the prongs being configured to direct the gases flow to an orifice of the patient;a gases flow manifold part comprising a gases inlet for receiving a flow of gas from a gas source, and a gases outlet for delivering the flow of gas to the prongs of the body;the nasal cannula interface comprising a patient sensor configured to measure a parameter; the patient sensor being positioned between the prongs, the body comprising a recess adjacent the face of the patient.

The patient sensor may comprise a pulse oximeter.

The nasal cannula interface may comprise a plurality of patient sensors.

The gases flow manifold part may comprise a recessed portion between the prongs and the sensor positioned in the recess, andthe nasal cannula further comprising a manifold part received within an opening in the body (i.e. face mount part), wherein the manifold part comprises a dip, wherein the dip in the manifold portion aligns with the recessed in the body when the manifold is inserted into the body.

According to an aspect of this disclosure there is provided a nasal cannula interface comprising: a face mount part having a base portion and at least one nasal prong extending from the base portion and capable of fitting in at least one of a user's nares, anda gases flow manifold part having a gases inlet for receiving a flow of gas from a gas source, and a gases outlet for delivering the flow of gas to the at least one nasal prong of the face mount part, the manifold part being adapted to be received by the base portion of the face mount part to fluidly connect the outlet of the manifold with the at least one nasal prong of the face mount part, and wherein the manifold part further comprises a recess; a patient sensor being positioned in the recess.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:a nasal cannula defining at least a portion of a gases flow path and comprising: a body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient; andone or more sensors configured to measure a parameter;wherein the sensor is configured to contact the nose of the patient when the nasal cannula interface is in use.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:a nasal cannula defining at least a portion of a gases flow path and comprising:a body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient, andone or more sensors configured to measure a parameter,wherein the sensor is configured to contact the upper lip of the patient when the nasal cannula interface is in use.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:a nasal cannula defining at least a portion of a gases flow path and comprising:a body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient, andone or more sensors configured to measure a parameter,wherein the sensor is configured to contact the lower lip of the patient when the nasal cannula interface is in use.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:a nasal cannula defining at least a portion of a gases flow path and comprising:a body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient, andone or more sensors configured to measure a parameter,wherein the sensor is configured to contact the mouth of the patient when the nasal cannula interface is in use.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:a nasal cannula defining at least a portion of a gases flow path and comprising:a body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient, andone or more sensors configured to measure a parameter,wherein the sensor is configured to contact the cheek of the patient when the nasal cannula interface is in use.

According to an aspect of this disclosure there is provided a nasal cannula interface for supplying a gases flow to a patient comprising:a nasal cannula defining at least a portion of a gases flow path and comprising:a body having a base portion and at least one prong extending from the base portion, the at least one prong being configured to direct the gases flow to an orifice of the patient, andone or more sensors configured to measure a parameter, wherein the sensor is configured to contact the neck of the patient when the nasal cannula interface is in use.

DETAILED DESCRIPTION

Certain embodiments and examples of a respiratory support system, and patient interfaces for such a system, are described herein. Those of skill in the art will appreciate that the disclosure extends beyond the specifically disclosed embodiments 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 embodiments described herein.

Patients suffering from various health conditions and diseases can benefit from respiratory support. For example, patients suffering from conditions such as chronic obstructive pulmonary disease (COPD), pneumonia, asthma, bronchopulmonary dysplasia, heart failure, cystic fibrosis, sleep apnea, lung disease, trauma to the respiratory system, acute respiratory distress, receiving pre- and post-operative oxygen delivery, and other conditions or diseases can benefit from respiratory support. As a part of providing a patient with respiratory support, one or more physiological parameters of the patient may be measured by a patient sensor for the purpose of monitoring the patient's health. The patient sensor may be a pulse oximeter, which provides information relating to heart rate and blood oxygen saturation (SpO2).

When providing a patient with respiratory support, in particular supplemental oxygen therapy, a common method of monitoring the patient's health is to ensure that their SpO2does not drop too low (e.g., typically below about 90%). However, supplying the patient with too much oxygen can over oxygenate their blood, and is also considered dangerous. Generally, the patient's SpO2is kept in a range from about 80% to about 99%, and preferably about 92% to about 96%, although these ranges may differ due to patient conditions, and/or from patient to patient.

Due to various patient factors such as respiratory rate, lung tidal volume, heart rate, activity levels, height, weight, age, gender, and other factors, there is no one prescribed level of supplemental oxygen that can consistently achieve an SpO2response in the targeted range for each patient. Individual patients regularly need their fraction of oxygen delivered to the patient (FdO2) monitored and adjusted to ensure they are receiving the correct FdO2to achieve the targeted SpO2. Achieving a correct and consistent SpO2is an important factor in treating patients with various health conditions or diseases. Additionally, patients suffering from these health problems may find benefit from a system that automatically controls oxygen saturation. The present disclosure is applicable to a wide range of patients that require fast and accurate oxygen saturation control.

The fraction of oxygen delivered to a patient (FdO2) may be controlled manually. For example, a user can manually adjust an oxygen supply valve to change the flow rate or fraction of oxygen being delivered to the patient. The user can determine SpO2levels of the patient using a patient monitor, such as a pulse oximeter. The SpO2measurements can be displayed on respiratory support apparatus10or on the pulse oximeter itself. The user can continue to manually adjust the amount of oxygen being delivered to the patient until the SpO2level of the patient reaches a determined level.

When a patient sensor is used as a part of the respiratory support system, the user is required to mount the patient sensor to the patient. This adds another task required of the user to an already potentially large set of tasks required for setting up the respiratory support system. Additionally, the separate patient sensor can lead to problems such as incorrect mounting of the sensor leading to incorrect measurement and/or the sensor falling off during use.

As such, a patient interface which incorporates the patient sensor allows the use of the patient sensor without increasing the workload of the user. This may have benefits in a hospital setting, in which a single clinician might have a large group of patients for whom they need to address. Additionally, this may have benefits in a home setting, as it simplifies the setup process for a patient who may need to perform these tasks themselves. Furthermore, integrating the patient sensor into the patient interface helps ensure correct orientation of the patient sensor and prevents the patient sensor from falling off during use.

This disclosure references conduit heaters, which is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art (that is, it is not to be limited to a special or customized meaning) and includes, without limitation, one or more heater strips, one or more heater wires, and/or one or more conductive elements that produce heat when electrical power is provided. Examples of such conduit heaters include wires made of a conductive metal (e.g., copper), conductive polymers, conductive inks printed on a surface of a conduit, conductive materials used to create a track on a conduit, and the like.

Furthermore, the disclosure references conduits, limbs, and medical conduits in the context of gas delivery. Conduit, for example, is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and includes, without limitation, passageways having a variety of cross-sections such as cylindrical and non-cylindrical passageways.

The disclosed systems, apparatuses and medical conduits can also be used in breathing circuits configured to provide a continuous, variable, or bi-level positive airway pressure (PAP) therapy or other form of respiratory support such as high flow or low flow oxygen therapy. The breathing circuit may for example comprising an inspiratory circuit which at a minimum includes the inspiratory gases pathway (including all the components) from the gases supply to the patient interface.

A respiratory support system may comprise a respiratory support apparatus10and the patient interface with an integrated sensor as shown inFIG.1. The respiratory support apparatus10may be configured to provide high flow therapy for example. The respiratory support apparatus10may comprise a main housing100that contains a flow generator11, such as in the form of a motor/impeller arrangement (for example, a blower), an optional humidifier12, a controller13, and a user interface14(comprising, for example, a display and input device(s) such as button(s), a touch screen, or the like). The humidifier may comprise a heater bay comprising a heating element such as a heater plate and configured to receive a humidification chamber. In use the humidification chamber receives heat from the heating element to raise the temperature of a body of water contained within the humidification chamber. The gases flow is passed over the body of water to add heat and humidity to the gases flow.

The controller13can be configured or programmed to control the operation of the apparatus. For example, the controller can control components of the apparatus, including but not limited to: operating the flow generator11to create a flow of gas (gases flow) for delivery to a patient, operating the humidifier12(if present) to humidify and/or heat the generated gases flow, control a flow of oxygen into the flow generator, receiving user input from the user interface14for reconfiguration and/or user-defined operation of the apparatus10, and outputting information (for example on the display) to the user. The user can be a patient, healthcare professional, or anyone else interested in using the apparatus. As used herein, a “gases flow” can refer to any flow of gases that may be used in the breathing assistance or respiratory support apparatus10, such as a flow of ambient air, a flow comprising substantially 100% oxygen, a flow comprising some combination of ambient air and oxygen, and/or the like.

An inspiratory conduit16is coupled at one end to a gases flow outlet21in the housing100of the respiratory support apparatus10. In an alternative configuration, the inspiratory conduit16is coupled at one end to a gases flow outlet of the humidifier12. The inspiratory conduit16is coupled at another end to a patient interface17such as a non-sealed nasal cannula with a body19comprising one or more nasal prongs18. Additionally, or alternatively, the inspiratory conduit16can be coupled to a face mask, a nasal mask, a nasal pillows mask, an endotracheal tube, a tracheostomy interface, and/or the like. The gases flow that is generated by the respiratory support apparatus10may be humidified and delivered to the patient via the inspiratory conduit16through the cannula17. The inspiratory conduit16can have a conduit heater such as one or more heater wires16ato heat gases flow passing through to the patient. The conduit heater can be under the control of the controller13. The respiratory support apparatus10, inspiratory conduit16, and patient interface17together can form a respiratory support system.

The controller13can control the flow generator11to generate a gases flow of the desired flow rate. The controller13can also control a supplemental oxygen inlet to allow for delivery of supplemental oxygen, the humidifier12(if present) can humidify the gases flow and/or heat the gases flow to an appropriate level, and/or the like. The gases flow is directed out through the inspiratory conduit16and cannula17to the patient. The controller13can also control a heating element in the humidifier12and/or the heating element16ain the inspiratory conduit16to heat the gas to a desired temperature for a desired level of therapy and/or level of comfort for the patient. The controller13can be programmed with or can determine a suitable target temperature of the gases flow.

The oxygen inlet port28can include a valve through which a pressurized gas may enter the respiratory support apparatus10. The valve can control a flow of oxygen into the respiratory support apparatus10. The valve can be any type of valve, including a proportional valve or a binary valve. The source of oxygen can be an oxygen tank or a hospital oxygen supply. Medical grade oxygen is typically between 95% and 100% purity. Oxygen sources of lower purity can also be used. Examples of valve modules and filters are disclosed in U.S. Provisional Application No. 62/409,543, titled “Valve Modules and Filter”, filed on Oct. 18, 2016, and U.S. Provisional Application No. 62/488,841, titled “Valve Modules and Filter”, filed on Apr. 23, 2017, which are hereby incorporated by reference in their entireties.

The respiratory support apparatus10can measure and control the oxygen content of the gas being delivered to the patient, and therefore the oxygen content of the gas inspired by the patient. During high flow therapy, the high flow rate of gas delivered meets or exceeds the peak inspiratory demand of the patient. This means that the volume of gas delivered by the respiratory support apparatus10to the patient during inspiration meets, or is in excess of, the volume of gas inspired by the patient during inspiration. High flow therapy therefore helps to prevent entrainment of ambient air when the patient breathes in, as well as flushing the patient's airways of expired gas. So long as the flow rate of delivered gas meets or exceeds peak inspiratory demand of the patient, entrainment of ambient air is prevented, and the gas delivered by the respiratory support apparatus10is substantially the same as the gas the patient breathes in. As such, the oxygen concentration measured in the respiratory support apparatus10, fraction of delivered oxygen, (FdO2) is substantially the same as the oxygen concentration the user is breathing, fraction of inspired oxygen (FiO2), and as such the terms may can be seen as equivalent.

Operation sensors3a,3b,3c, such as flow, temperature, humidity, and/or pressure sensors can be placed in various locations in the respiratory support apparatus10. Additional sensors (for example, sensors20,25) may be placed in various locations on the inspiratory conduit16and/or cannula17(for example, there may be a temperature sensor at or near the end of the inspiratory conduit16). The sensors20,25may also be a CO2 sensor or a pressure sensor or a flow sensor or oxygen sensor. Output from the sensors can be received by the controller13, to assist the controller in operating the respiratory support apparatus10in a manner that provides suitable therapy. In some configurations, providing suitable therapy includes meeting a patient's peak inspiratory demand. The apparatus10may have a transmitter and/or receiver15to enable the controller13to receive signals8from the operation and any additional sensors and/or to control the various components of the respiratory support apparatus10, including but not limited to the flow generator11, humidifier12, and heater wire16a, or accessories or peripherals associated with the respiratory support apparatus10. Additionally, or alternatively, the transmitter and/or receiver15may deliver data to a remote server or enable remote control of the apparatus10.

The respiratory support apparatus10may receive measurements from one or more gases composition sensors. The gases composition sensors may be located within the respiratory support apparatus10, the inspiratory conduit16, the patient interface, or at any other suitable location. The gases composition sensors may be located at or downstream of a location where the ambient air and any supplemental gases flow, such as oxygen, have finished mixing. The gases composition sensors may be configured to measure oxygen concentration. The gases composition sensors may be an ultrasonic transducer system, also referred to herein as an ultrasonic sensor system.

The respiratory support apparatus10may be configured to connect to a patient sensor29as described below, such as a pulse oximeter or a patient monitoring system, to measure one or more physiological parameters of the patient, such as a patient's blood oxygen saturation (SpO2) (i.e. peripheral arterial oxyhaemoglobin), heart rate, respiratory rate, perfusion index, and provide a measure of signal quality. The patient sensor29may be part of the additional sensors20,25or may be a separate additional sensor that could be located on or in the patient interface or delivery conduit. The sensor can communicate with the controller13through a wired connection or by communication through a wireless transmitter on the sensor. Sensors are available that are designed for different age groups and to be connected to different locations on the patient, which can be used with the respiratory support apparatus.

The pulse oximeter connects to a processor in the respiratory support apparatus10and constantly provides signals indicative of the patient's blood oxygen saturation. The patient sensor29may be a hot swappable device. The term “hot swappable device” as used herein refers to a device that can be attached or interchanged during operation of the respiratory support apparatus10. For example, the patient sensor29may connect to the respiratory support apparatus10using a USB interface with a lead or wire or using wireless communication protocols (such as, for example, near field communication, WiFi or Bluetooth®). The output of the pulse oximeter may be displayed on the graphical user interface14. The measurements from the pulse oximeter29may also be transmitted to a remote patient management system (e.g. a remote server system) via a suitable wireless protocol e.g. via GSM etc.

When the patient sensor29is disconnected (either from the patient or from the respiratory support apparatus) during operation, the respiratory support apparatus10may continue to operate in its previous state of operation for a predefined time period. After the predefined time period, the respiratory support apparatus10may trigger an alarm, transition from automatic mode to manual mode, and/or exit control mode (e.g., automatic mode or manual mode) entirely.

The respiratory support apparatus10may be configured to recognise whether patient sensor29is a standalone patient sensor or a patient sensor that is located on or comprised by a patient interface17. The respiratory support apparatus10may recognise the sensor type by receiving identification information upon initial connection of the patient sensor29. The respiratory support apparatus10may recognise the sensor type through the way in which the signal from the patient sensor29is received. For example, an integrated patient sensor29may be configured to communicate with the respiratory support apparatus10via an electrical connection located at the gases outlet of the respiratory support apparatus10(as will be described herein), whilst a standalone patient sensor may be configured to connect to the respiratory support apparatus via a separate connection port.

The respiratory support apparatus10may be configured to use the output of a patient sensor29that is located on or comprised by a patient interface17to determine whether the patient is wearing the patient interface17. In this context, “wearing” refers to the patient interface17being mounted in a position on the patient's face such that the patient interface17can deliver the gases flow to the patient and the patient sensor29can measure one or more patient parameters. When the patient sensor29cannot reliably measure the one or more patient parameters it may produce a signal indicating such. Additionally, or alternatively, the patient sensor29may communicate a separate parameter such as signal quality. The respiratory support apparatus10may check this parameter against a threshold in determining whether the patient sensor29is able to reliably measure the one or more patient parameters. The respiratory support apparatus10may use a determination that the patient sensor29cannot reliably measure the one or more patient parameters in further determining that the patient is not wearing the patient interface17.

The respiratory support apparatus10may use the determination of whether the patient is wearing the patient interface17in activating or deactivating certain control algorithms, such as the closed loop SpO2controller, which will be described in detail later in the specification. The respiratory support apparatus10may use the indication in increasing or decreasing the flow rate. For example, the respiratory support apparatus10may reduce the flow rate when the patient is not wearing the patient interface17in order to reduce noise and power consumption. The respiratory support apparatus10may use the indication for generating an alarm, such as alarming if the patient has removed the patient interface17. This alarm may occur instantaneously or within a set period of time after the output of the patient sensor29is lost.

In a further configuration, the respiratory support apparatus10is configured to switch to a standby mode when the output of the patient sensor29indicates that the patient is not wearing the patient interface17. In the standby mode, the respiratory support apparatus10may be configured to control the blower to operate at a reduced motor speed. The reduced motor speed may be a minimum operating speed for the blower. The reduced motor speed may be about 1000 RPM-2000 RPM. In the standby mode, the respiratory support apparatus10may be configured to control a blower to deliver a reduced flow rate. The reduced motor speed may be between about 1 LPM and 2 LPM.

The respiratory support apparatus10may comprise a high respiratory support apparatus. 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 respiratory assistance system 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 liters per minute (LPM) to about seventy liters per minute or greater. Typical flow rates for pediatric patients (such as neonates, infants and children) often range from, but are not limited to, about one liter per minute per kilogram of patient weight to about three liters 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. The flow rates used to achieve “high flow” may be any of the flow rates listed below. 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 25 LPM and 75 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 respiratory support apparatus with an adult patient, a neonatal, infant, or child patient, may 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. The respiratory support apparatus10can deliver any concentration of oxygen (e.g., FdO2), up to 100%, at any flow rate between about 1 LPM and about 100 LPM. In some configurations, any of the flow rates can be in combination with oxygen concentrations (FdO2s) of about 20%-30%, 21%-30%, 21%-40%, 30%-40%, 40%-50%, 50%-60%, 60%-70%, 70%-80%, 80%-90%, and 90%-100%. In some combinations, the flow rate can be between about 25 LPM and 75 LPM in combination with an oxygen concentration (FdO2) of about 20%-30%, 21%-30%, 21%-40%, 30%-40%, 40%-50%, 50%-60%, 60%-70%, 70%-80%, 80%-90%, and 90%-100%. In some configurations, the respiratory support apparatus10may include safety thresholds when operating in manual mode that prevent a user from delivering to much oxygen to the patient.

High flow therapy may be administered to the nares of a user and/or orally, or via a tracheostomy interface. High flow therapy may deliver gases to a user at a flow rate at or exceeding the intended user's peak inspiratory flow requirements. The 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 minimizing re-breathing 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. The nasal cannula may be configured to deliver breathing gases to the nares of a user at a flow rate exceeding the intended user's peak inspiratory flow requirements.

The term “non-sealing 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 generator11) that does not completely occlude the airway of the patient. 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 more of a nare or mouth of the patient. For a nasal cannula the airway is through the nares.

The respiratory support apparatus10can include an ambient air inlet port27to entrain ambient room air. The respiratory support apparatus10may also include an oxygen inlet port28leading to a valve through which a pressurized gas may enter the respiratory support apparatus10. The valve can control a flow of oxygen into the respiratory support apparatus10. The valve can be any type of valve, including a proportional valve or a binary valve.

In a further configuration, the respiratory support apparatus10includes two or more oxygen inlet ports. A first oxygen inlet port, also referred to as a high pressure oxygen inlet, receives oxygen from an oxygen source at a set pressure. The flow rate of the oxygen from the first oxygen inlet port is then regulated by a valve as described above. A second oxygen inlet port, also referred to as a low pressure oxygen inlet, receives oxygen from an oxygen source at a set flow rate. The flow rate of oxygen through the second oxygen inlet port can then be adjusted by adjusting an external flow regulator on the oxygen source.

The blower can operate at a motor speed of greater than about 1,000 RPM and less than about 30,000 RPM, greater than about 2,000 RPM and less than about 21,000 RPM, greater than about 4,000 RPM and less than about 19,000 RPM or between any of the foregoing values. Operation of the blower can mix the gases flow entering the blower through the inlet ports. Using the blower as the mixer can decrease the pressure drop that otherwise occurs in a system with a separate mixer, such as a static mixer comprising baffles, because mixing requires energy. Having a static mixer can also increase the volume of the gas flow path between the valve and the gases composition sensor, which can further increase the delay between when the valve current is changed and when a corresponding change in oxygen concentration is measured.

Based on user inputs and the therapy supplied by the respiratory support apparatus10, the controller13can determine a target output parameter for the blower. The controller can receive measurements of the target output parameter, and based on the difference between determined flow rate and the measured flow rate, the controller can adjust the speed of the blower.

With reference again toFIG.1, the controller13can be programmed with or configured to execute a closed loop control system for controlling the operation of the respiratory support apparatus. The closed loop control system can be configured to ensure the patient's SpO2reaches a target level and consistently remains at or near this level.

The controller13can receive input(s) from a user that can be used by the controller13to execute the closed loop control system. The target SpO2value can be a single value or a range of values. The value(s) may be pre-set, chosen by a clinician, or determined based on the type of patient, where type of patient may refer to current affliction, and/or information about the patient such as age, weight, height, gender, and other patient characteristics. The target SpO2value may be input by a clinician or user via a user interface on the apparatus and received by the controller13. Similarly, the target SpO2may be two values, each selected in any way described above. The two values represent a range of acceptable values for the patient's SpO2. The controller can target a value within said range. The targeted value may be the middle value of the range, or any other value within the range, which may be pre-set or selected by a user. Alternatively, the range may be automatically set based on the targeted value of SpO2. The controller can be configured to have one or more set responses when the patient's SpO2value moves outside of the range. The responses may include alarming, changing to manual control of FdO2, changing the FdO2to a specific value, and/or other responses. The controller can have one or more ranges, where one or more different responses occur as it moves outside of each range.

Generally, SpO2is controlled between about 80% and about 100%, or about 80% and about 90%, or about 88% and about 92%, or about 90% and about 99%, or about 92% and about 96%. The SpO2may be controlled between any two suitable values from any two of the aforementioned ranges. The target SpO2may be between about 80% and about 100%, or between about 80% and about 90%, or between about 88% and about 92%, or between about 90% and about 99%, or between about 92% and about 96%, or about 94%, or 94% or about 90%, or 90%, or about 85%, or 85%. The SpO2target may be any value between any two suitable values from any two of the aforementioned ranges. The SpO2target can correspond to the middle of the SpO2for a defined range.

The FdO2can be configured to be controlled within a range. As discussed previously, the oxygen concentration measured in the apparatus (FdO2) is substantially the same as the oxygen concentration the patient is breathing (FiO2) so long as the flow rate meets or exceeds the peak inspiratory demand of the patient, and as such the terms may can be seen as equivalent. Each of the limits of the range may be pre-set, selected by a user, or determined based on the type of patient, where the type of patient may refer to current affliction, and/or information about the patient such as age, weight, height, gender, and/or other patient characteristics. Alternatively, a single value for FdO2may be selected, and the range may be determined at least partially based on this value. For example, the range may be a set amount above and below the selected FdO2. The selected FdO2may be used as the starting point for the controller. The system may have one or more responses if the controller tries to move the FdO2outside of the range. These responses may include alarming, preventing the FdO2 moving outside of the range, switching to manual control of FdO2, and/or switching to a specific FdO2. The respiratory support apparatus10may have one or more ranges where one or more different responses occur as it reaches the limit of each range.

With reference toFIG.2a schematic diagram of the closed loop control system1000is illustrated. The closed loop control system may utilize two control loops. The first control loop may be implemented by the SpO2controller. The SpO2controller can determine a target FdO2based in part on the target SpO2and/or the measured SpO2. As discussed above, the target SpO2value can be a single value or a range of acceptable values. The value(s) may be pre-set, chosen by a clinician, or determined automatically based on client characteristics. Generally, target SpO2values are received or determined before or at the beginning of a therapy session, though target SpO2values may be received at any time during the therapy session. During a therapy session, the SpO2controller can also receive as inputs: measured FdO2reading(s) from a gases composition sensor, and measured SpO2reading(s) and a signal quality reading(s) from the patient sensor29. In some configurations, the SpO2controller can receive target FdO2as an input, in such a case, the output of the SpO2controller may be provided directly back to the SpO2controller as the input. Based at least in part on the inputs, the SpO2controller can output a target FdO2to the second control loop.

During the therapy session, the SpO2and FdO2controllers can continue to automatically control the operation of the respiratory support apparatus until the therapy session ends or an event triggers a change from the automatic mode to manual mode.

For example, a respiratory support system using blood oxygen saturation measurements from a pulse oximeter to automatically adjust the fraction of oxygen of the gases flow being delivered to a patient via a patient interface is described in our earlier PCT application WO2019/070136 (herein WO' 136) filed on 5 Oct. 2018 and hereby incorporated by reference in its entirety.

The respiratory support system described in WO' 136 uses a separate pulse oximeter and patient interface. As such, a clinician is required to attach both the pulse oximeter and the patient interface to the patient individually, with both of these components also being connected separately to a respiratory support apparatus.

With reference again toFIG.1, the controller13can be programmed with or configured to execute an FdO2control system for controlling the operation of the respiratory support apparatus.

The FdO2control system can be configured to ensure that the instantaneous FdO2is maintained at a target level at all points during a therapy session. The controller can measure the FdO2, compare it with the target FdO2, and then adjust the oxygen inlet valve accordingly. However, when the FdO2sensors are located at a non-insignificant distance away from the valve, there is a time delay between when a change is made to the valve and when a corresponding change in the FdO2is measured. The controller may adjust the valve after the time delay. However, if the flow rate is fluctuating, then the controller may be able to achieve the target FdO2on average, but not at a continuous and substantially instantaneous basis. As shown inFIG.2, in order to maintain the FdO2at the target level at a continuous and substantially instantaneous basis, without moving the FdO2sensors closer to the valve, the FdO2controller can factor in the measurement of a total flow rate into the control of the valve.

A patient interface17is connected to one end of the inspiratory conduit16and is used to provide a breathable gases flow to the patient. During setup of the respiratory support apparatus10, a clinician or the patient is required to attach the patient interface17to the patient. Additionally, if a standalone patient sensor29is also to be used, then the clinician or the patient are also required to attach this to the patient. Both of the patient interface17and the patient sensor29then also need to be attached to the respiratory support apparatus10itself. Forming these various connections can be undesirable.

The patient interface17has one or more patient sensors29. The one or more integrated patient sensors29may be configured to measure the blood oxygen saturation of the patient. The one or more integrated patient sensors29are positioned on the patient interface17to facilitate the measuring of the patient's blood oxygen saturation.

The patient interface17may be used with the respiratory support apparatus10described above. Alternatively, the patient interface17may be used with any other respiratory support apparatus that may utilize a patient interface17with patient sensors29, such as a ventilator, a CPAP apparatus, a standalone humidifier, and/or an oxygen blender.

The patient interface17may comprise a nasal cannula interface, as shown inFIGS.3to33. In this configuration, the nasal cannula interface broadly comprises a head securement assembly and a nasal cannula30, and also includes a gases inlet conduit62. The head securement assembly enables a user to place and maintain the nasal cannula30in the correct operational position. The gases inlet conduit62forms a fluid or gases connection between the outlet end of the inspiratory conduit16and the nasal cannula30to allow fluids or gases to flow between the inspiratory conduit and nasal cannula. The gases inlet conduit62and detail of the main portion of the nasal cannula30will be described in detail below.

The head securement assembly of the nasal cannula30may comprise one or more straps. The one or more straps may include two front straps50, a rear strap53a, and a top strap53b, as shown inFIG.3. In some configurations, the proximal end of the front straps50are removably connected to the nasal cannula30. In other configurations, the proximal ends of the front straps50are non-removably connected to the nasal cannula30. The rear strap53aand the top strap53bextend between the distal ends of the front straps50. In use, the rear strap53awraps around the back of the patient's head. In use, the top strap53bwraps around the top of the patient's head. In some configurations the head securement assembly is adjustable to allow patients of different head shapes and sizes to use the nasal cannula30. For example, an adjuster such as an adjustment buckle54may be included which allows a patient to loosen or tighten the top strap53b.

In some configurations, one or more of the straps are substantially elastic (i.e. made from an elastic material e.g. lycra, that can stretch to accommodate a patient's head). In some configurations, one or more of the straps are substantially rigid. In some configurations, one or more of the straps are made of a substantially rigid material. In some configurations, one or more of the straps are substantially inextensible. In some configurations, one or more of the straps are made of a substantially inextensible material. In some configurations, one or more of the straps are self-supporting. In some configurations, one or more of the straps maintain their shape when not in use.

Alternatively, the patient interface17is secured to the patient's head and face by front straps50and a single rear strap53aattached to the front straps50. The rear strap is attached to the front straps50via a buckle54. Alternatively, the rear strap53ais integral with the front straps50. The buckle54allows a patient to loosen or tighten the front straps50based on individual preference. Alternatively, the integral front50and rear straps53aare elastic and can be stretched over a patient's head. The elasticity of the straps exerts a force upon the head to hold the nasal cannula30in the optimal position when in use. Elastic straps50,53acan be used with the adjustment buckle54or the elastic straps50,53amay be used on their own without the buckle54.

The head securement assembly may also include a loop55which holds and supports the gases inlet conduit62at or close to the inlet end as shown inFIG.3. The loop55comprises a first end connected to one of the front straps50. The first end may be slidably connected to the front strap50. The loop55comprises a second end connected to the gases inlet conduit62. The second end may be removably connected to the gases inlet conduit62. Alternatively, the interface may comprise a tube clip that is connected to the tube and can be removably coupled to the cannula. The tube clip supports the weight of the inlet conduit62and reduces the moment cause by the conduit62, thereby improving stability of the patient interface17. The clip helps to reduce dislodgement of the patient interface17. The clip may be formed of a rigid material.

A lanyard63may also be provided with the patient interface17.FIG.3shows an example of a lanyard63. In the configuration shown, the lanyard63is connected to the gases inlet conduit62. Alternatively, the lanyard63is connected at a location at or close to the connection between the inspiratory conduit16and the gases inlet conduit62. In use, the lanyard63supports the weight of the inspiratory conduit16and the gases inlet conduit62. A toggle64is provided with the lanyard63to allow adjustment of the lanyard's length. The toggle64makes the lanyard63suitable for any sized patient to use the patient interface17. The lanyard63supports at least a portion of the weight of the inspiratory conduit16in use, such that the weight does not act on the user or the nasal cannula30. The use of the lanyard63reduces the portion of the combined weight of the inspiratory conduit16and the gases inlet conduit62that pulls on the nasal cannula30, helping to prevent the nasal prongs33,34from interfering with the sensitive lining of the nasal passages, or becoming displaced or misaligned in use. In the configuration shown the lanyard63is loose fitting around the neck so as to reduce the chance of strangulation of the user. The lanyard63also provides a convenient way of supporting the inspiratory conduit16and the gases inlet conduit62. This allows the patient to turn in bed without tugging or pulling on the inspiratory conduit16and helps avoid having the gases inlet conduit62from overheating under the blankets. In one configuration the lanyard63has a clip that allows the lanyard to be opened and closed by a user in order place and secure the lanyard63around a user's neck. The clips comprises a male and female connector that snap fit together. The clip is disconnected by pulling one end of the lanyard63. The clip is easily disconnectable, and uncouples when the user pulls on one side of the lanyard. This allows the lanyard63to be removed quickly, for example in an emergency situation, such as if the patient needs to be intubated.

The gases inlet conduit62will now be described in detail. The gases inlet conduit62is a short length of conduit or tubing relative to the inspiratory conduit16which runs between the outlet of the inspiratory conduit16and the nasal cannula30. In use, the gases inlet conduit62forms a lumen that defines a gases pathway between the inspiratory conduit16and the patient interface17, such that the gases flow exits the inspiratory conduit16and enter the gases inlet conduit62, travelling along the gases inlet conduit62to the patient interface17to be delivered to the patient. One reason that secondary conduits such as the gases inlet conduit62can be used is as follows: the inspiratory conduit16is relatively heavy and cumbersome as it is used to transport the gases flow over a reasonably long distance (from the humidifier unit2to a point close to the patient). The inspiratory conduit16is therefore required to have a wall that is strong enough to support its own weight without collapsing. As the inspiratory conduit16is typically relatively long (e.g. 8 to 10 feet), this additional length and the thicker wall structure adds to the weight of the inspiratory conduit16. If the outlet of the inspiratory conduit16is connected directly to the patient interface in such a manner that the patient is required to support this weight, this can cause discomfort to the patient due to the weight of inspiratory conduit16acting on the patient. Furthermore, the weight of the inspiratory conduit16can pull on the patient interface17and cause it to become dislodged or misaligned. A lighter, shorter secondary conduit (e.g. gases inlet conduit62) running between the outlet of the inspiratory conduit16and the patient interface17can be used.

Gases inlet conduit62is lighter and shorter than the inspiratory conduit16, and as outlined above, is generally used with e.g. a lanyard63connected to the gases inlet conduit62or to the connection between the inspiratory conduit16and the gases inlet conduit62. In use, the lanyard63(as outlined above) supports at least a portion of the weight of the inspiratory conduit16, such that the patient interface17only needs to support the comparatively lighter the gases inlet conduit62. Furthermore, in configurations in which the lanyard63connects to the end of the gases inlet conduit62, the patient does not need to remove the lanyard63when disconnecting the inlet conduit62from the inspiratory conduit.

Various aspects of the nasal cannula30shall now be described in more detail with reference toFIGS.4to33. Unless otherwise stated, the nasal cannula30illustrated inFIGS.4to33includes all of the features of the generalized nasal cannula described with reference toFIG.3.

The nasal cannula30comprises two main parts: an interface connector35and a body32. Example configurations of these two parts will now be described with particular reference toFIGS.4and5.

The interface connector35is in use connected to and in fluid communication with the gases inlet conduit62as has been described above. However, it may be connected directly to the inspiratory conduit16in alternative embodiments.

The configuration ofFIG.5shows the interface connector35as being detachable from the remainder of the nasal cannula30. Alternatively, the interface connector35may be an integral part of the nasal cannula30. Alternatively, the interface connector35and the nasal cannula30form a onetime fit, such that the user is prevented from disassembling the two components following the initial assembly. In the integrated or one time fit configurations, a continuous gases flow path is formed through the inspiratory conduit16, the gases inlet conduit62, the interface connector35, and to the prongs of the nasal cannula30.

In some configurations interface connector35is generally tubular in shape having a substantially circular inlet59on one side that curves to an oval or elliptical outlet37, the outlet37being formed on one side of the interface connector35so that it is perpendicular to the inlet59. The circular inlet59in the illustrated form receives the patient end of the gases inlet conduit62, such that the gases flow from the gases inlet conduit62can pass through the interface connector35.

In some configurations the interface connector35is integrated with or permanently coupled to the gases inlet conduit62. Alternatively, the interface connector35is removably attached to the gases inlet conduit62. The interface connector35engages with the body32so that the gases flow can pass through the outlet37and transfer from the gases inlet conduit62to the patient through the nasal prongs33,34(described in detail below).

In some configurations the interface connector35is manufactured from a hard plastic material that only deforms under relatively high loading conditions (that is, it cannot easily be crushed in the hand of a user). The interface connector35may be moulded, injection moulded, machined or cast.

The interface connector35in use is connected to the body32, so that the gases flow exiting the interface connector35enter the body32. The body32will now be described in detail.

The body32includes the nasal prongs33,34extending from a base portion39of the body32. The gases flow passes through the body32to the nasal prongs33,34and is delivered to the patient. In some configurations, the nasal prongs33,34extend parallel to each other. In some configurations, the nasal prongs33,34curve rearwards from the face mount portion32. In some configurations, the nasal prongs33,34curve towards each other. The structure of the prongs33,34will be described in detail below.

The body32of the illustrated embodiment comprises side arms31and a tubular member38comprising a recess, integrally moulded together as shown inFIGS.4and5. The tubular member38extends below the body32and is adapted to receive the interface connector35(for the configurations where the body32and the interface connector35are separable or separate items). The body32has a lip39that extends around the upper edge of the tubular member38. The interface connector35is connected to the body32by a friction fit and the lip39on the body32helps to grip the interface connector35and form a sealed connection between the interface connector35and the body32. The tubular member38comprises a rib40which extends below the body32. The rib40helps to cradle and hold the interface connector35in the correct position as it engages with the body32, the rib40extending around the outside of the interface connector35. Outlet37on the interface connector35aligns in use with the underside of the face mount32portion when the interface connector35is connected to the body32. This alignment reduces the amount of gases which leak out of the nasal cannula30, allowing effective treatment of the user by delivering maximum amount of humidified gases.

The side arms31are used to attach the front straps50to the body32. The side arms31extend from either side of the body32. In some configurations, the side arms31are formed as an integral part of the body32. In use, the front straps50are attached to the side arms31so that the patient interface can be worn by a user. In some configurations the ends of the front straps50are looped through a pair of slits on the side arms31, with the ends including a hook and loop fastener or similar to hold the ends in place when they are looped back on themselves. Alternatively, the front straps50or loops66may be clipped onto the side arms31, for example by way of co-operating male-female clips, or adhesively attached to the side arms31.

In some configurations, the body32, nasal prongs33,34, side arms31and the tubular member38are all manufactured as one continuous item. The body32, nasal prongs33,34, side arms31and the tubular member38are all manufactured out of flexible polymer material such as a soft thermoplastic elastomer (TPE), or silicone.

The following is a description of the nasal prongs. In the following description the term “rear”, or “back” or any such synonym refers to that part of the structure that faces towards and is closest to the patient's face when the nasal cannula is in use. The term “front” or “forward” or any such synonym refers to the side, face or part which faces away from and is furthest away from the face of a user of patient in use. The term “top” or “upper” refers to the side, face or part that is pointing away from the floor, when a user or patient wearing the interface is standing or sitting upright and looking forward. The term “bottom” or “lower” refers to the side, face or part that is directed or pointing toward the ground, again when a user or patient wearing the interface is standing or sitting upright and looking forward. For example,FIG.3illustrates the patient interface17being worn by the patient, wherein the directions described above can be evaluated with reference to this figure. The definitions for these directions remain consistent throughout, including in figures where the patient interface17is shown without the patient.

In some configurations the body32includes two nasal prongs33,34extending upwards and curving inwards from the upper surface of the body32as shown inFIGS.4to10. Referring toFIGS.4to10, the nasal prongs33,34extend from the upper surface of the body32and each prong is placed in each nostril of the patient when the nasal cannula is in use. The prongs33,34are configured to deliver the gases flow to a patient. The prongs33,34receive the humidified gases flow from the gases inlet conduit62via the gases inlet conduit62, the interface connector35and the body32. The nasal prongs33,34are therefore in fluid connection with the interface connector35and receive the gases flow from the gases inlet conduit62.

Referring toFIGS.7to8andFIG.12, a patient sensor29is located on the body32of the nasal cannula30. In some configurations, the patient sensor29is located on the nasal cannula30such that it contacts the patient's skin during use. The patient sensor29may have an adhesive surface such that it can be secured in contact with the patient's skin.

The outer surfaces of the body32of the nasal cannula30may generally be divided into outwardly facing surfaces and inwardly facing surfaces. The term “outwardly facing surface” used herein can refer to an outer surface of the body32that faces away from the patient whilst the nasal cannula30is in use. The term “inwardly facing surface” used herein can refer to an outer surface of the body32that faces towards from the patient whilst the nasal cannula30is in use. The front and bottom sides of the body32can be considered to be outwardly facing surfaces, whilst the rear side can be considered to be an inwardly facing surface. The central portion of the top side of the body32that is located under the patient's nose in use may be considered to be an inwardly facing surface, whilst the remaining side portions of the of the top side may be considered to be outwardly facing surfaces.

Referring now toFIG.7, a first location for the patient sensor29is shown. In this configuration the patient sensor29is located on the rear surface103of the body32. In the illustrated configuration the patient sensor29is located in the centre of the rear surface103. Alternatively, the patient sensor29may be located anywhere on the rear surface103(e.g. rear surface is the surface closest to or in contact with the patient when the interface17is in use), such as along one of the two side arms31. Providing the patient sensor29on the rear surface103causes the patient sensor29to be in contact with the patient's upper lip whilst the cannula is being worn.

Referring now toFIGS.8and9, a second location for the patient sensor29is shown. In this configuration the patient sensor29is located on the top surface104of the body32, between the nasal prongs33,34. Providing the patient sensor29to this surface causes the patient sensor29to be in contact with the patient's columella whilst the cannula is being worn.

In some configurations, the patient sensor29is a pulse oximeter.

In the configurations illustrated inFIGS.7to9, the patient sensor29is a reflectance pulse oximeter. The reflectance pulse oximeter comprises an emitter29aand a receiver29b. During use, the emitter29aemits light which is reflected off of the patient's skin, and then received by the receiver29b. Based on the wavelength of the received light, physiological parameters such as the patient's SpO2and heart rate can be calculated. The positions shown for the emitter29aand the receiver29bmay equally be reversed. Furthermore, for the first location, the emitter29aand the receiver29bare shown to be spaced horizontally. In an alternative configuration, the emitter29aand the receiver29bare spaced vertically. In an alternative configuration shown inFIG.8, the emitter29aand the receiver29bare spaced horizontally in the second location. In an alternative configuration shown inFIG.9, the emitter29aand the receiver29bare spaced in front/behind each other in the second location. Further orientations may be equally applicable.

In some configurations of the nasal cannula30, the patient sensor29may be located in a recess of the body32of the nasal cannula30. The shape of the recess corresponds to the shape of the patient sensor29, such that an outwardly facing surface of the patient sensor29sits flush with the surface of the body32. In configurations where the patient sensor is a pulse oximeter, the outwardly facing surface of the patient sensor29is the operative surface of the patient sensor29, i.e. the emitter29aand the receiver29b.

The patient sensor29can be considered to be “sitting flush” with a surface of the body32when the outwardly facing surface of the patient sensor29and the adjacent portions of the surface of the body32form a smooth combined surface. The combined surface is considered smooth when there is no significant indentation or protrusion at the boundary between the patient sensor29and the body32. An indentation or protrusion is only considered significant if it is perceptible to the user by sight and/or touch.

In some configurations, the combined surface is flat. In other configurations, the combined surface is curved. In other configurations, the combined surface is a mixture of curved and flat portions. In some configurations, the outwardly facing surface of the patient sensor29is tangential to the adjacent portions of the surface of the body32.

Referring now toFIG.10, a further configuration for the patient sensor29is shown. In this configuration the patient sensor29is located on the outer surface of one or more of the nasal prongs33,34. In a configuration in which the patient sensor29is a pulse oximeter, a transmissive pulse oximeter is used. The transmissive pulse oximeter comprises an emitter29aand a receiver29b. During use, the emitter29aemits light which is transmitted through a portion of the patient's body, and then received by the receiver29b. Based on the wavelength of the received light, physiological parameters such as the patient's SpO2and heart rate can be calculated. In some configurations, the emitter29ais located on a centrally facing outer surface of one of the nasal prongs33,34, and the receiver29bis located on the opposing centrally facing outer surface of the other one of the nasal prongs33,34, such that light is transmitted through the patient's septum.

Each of the nasal prongs33,34can have a notional central axis that runs through the centre of the lumen of each of the nasal prongs33,34from the base to the tip. During use, the central axis is parallel to the direction of the gases flow. The nasal prongs33,34may have a cross-section that has at least one flat edge, when said cross-section is taken perpendicular to the central axis defined above. For example, the cross-section may be a shape with entirely flat edges, such as a rectangle or a triangle. Alternatively, the cross-section may be a shape with a mix of one or more curved edges and at least one flat edge, such as a semicircle. This flat edge results in a flat surface along one face of each nasal prong33,34. In some configurations, the cross-section is consistent throughout the length of each nasal prong33,34. In other configurations, the size and/or dimensions of the cross-section changes throughout the length of each nasal prong33,34. For example, each nasal prong33,34may taper inwards along its length, but maintain a semicircular cross-section throughout. In further configurations, the nasal prongs33,34do not have a consistent cross-sectional shape throughout their length, but do have at least one flat outer surface.

The patient sensors29are located on the flat outer surface of the nasal prongs33,34. The flat surfaces of the nasal prongs33,34may be located on the inner faces of the nasal prongs33,34such that the two surfaces face each other. Using a flat surface as the location of the patient sensors29allows for a more consistent orientation, as a slight shift in placement during manufacturing does not result in a change in orientation. This is particular useful in the case of a transmissive pulse oximeter, as the transmissive pulse oximeters rely on the emitter29aand the receiver29bto be properly aligned. In some configurations, placing the patient sensors29on a flat surface aids in facilitating contact between the patient sensors and the patient's septum.

The nasal prongs33,34may be inclined towards each other when not in use. Once the nasal cannula30is mounted on the patient the nasal prongs33,34can elastically deform to fit the patient's nasal passages. This deformation results in a clamping force on the patient's septum. This clamping force helps to provide consistent contact between the patient's septum and the patient sensors29.

Alternatively, a transmissive pulse oximeter may be set up to transmit through the outer nasal wall of the patient. In this configuration, either the emitter29aor the receiver29bis located on an outwardly facing outer surface of one of the nasal prongs33,34, whilst the other component of the emitter29aand the receiver29bis located on an additional projection that clamps onto the outer surface of the patient's nasal passage during use. In some configurations the additional projection extends from the body32of the nasal cannula30. In some configurations the additional projection has a flat outer surface parallel to a flat outer surface on one of the nasal prongs33,34. The flat outer surface of the nasal prong33,34faces towards the additional projection. One of each of the emitter29aand the receiver29bare located on one of each of the flat surfaces.

In a further alternative configuration, a reflective pulse oximeter may be used instead of a transmissive pulse oximeter. In this configuration, both the emitter29aand the receiver29bis located on the same nasal prong33,34. Alternatively, a reflective pulse oximeter may be used by including both the emitter29aand the receiver29bon a supplementary projection that contacts the outer surface of the patient's nasal wall. In some configurations the supplementary projection extends from the body32of the nasal cannula30.

An alternative configuration of the nasal cannula30will now be described with referral toFIGS.11and12. In this configuration the head securement assembly comprises one or more facial pads44located on the side arms31. During use, the facial pads44may be attached to the patient's cheeks. In some configurations, the facial pads44have an adhesive surface that allows the facial pads44to be attached to the patient's cheeks. In certain scenarios this may be more comfortable for the patient, and may reduce the chance of the nasal cannula30shifting from its correct position during use. In order to allow the patient sensor29to contact the patient's skin, one or more cutouts may exist in the facial pads44corresponding to the position of the patient sensor29.

In the configuration shown inFIG.12, the patient sensors29are located on a side arm31of the body32of the nasal cannula30in the same region as the facial pad44. As the facial pad44is in contact with the patient's skin, a reflectance pulse oximeter (as described above) may be implemented. The emitter29aand receiver29bis located side by side in either facial pad44. The emitter29aand receiver29bsits flush with the surface of the facial pad44.

In an alternative configuration shown inFIGS.13to15, the facial pads may comprise a two-part releasable attachment or connection arrangement551. The releasable connection arrangement551acts between, and releasably connects, a pair of patches that are affixed to the patient and the patient interface17respectively.

The first patch is a dermal patch550that is adhered or otherwise attached to the patient's skin. The dermal patch has a patient side that faces the patient's skin and an interface side that faces the patient interface17. The patient side of the dermal patch550may be attached to the skin of a patient by a dermatologically sensitive adhesive, such as a hydrocolloid. The patient interface side of the dermal patch is provided with the first part553of the two-part releasable attachment or connection system551.

The second patch is a patient interface patch552. The patient interface patch552also has a patient side and an interface side. The patient side of the patient interface patch552is disposed adjacent the dermal patch when the patient interface17is engaged. The complimentary second part of the two-part releasable attachment or connection system553is affixed to the patient side of the patient interface patch552, so that the respective parts of the two-part releasable attachment or connection system551are easily engageable when the patches550,552are brought together. The interface side of the patient interface patch552is affixed to the patient interface17. The patient interface patch may be integrated with or suitably adhered to the patient interface17.

A part or corner of the patient interface patch552may include a region that does not attach to the dermal patch550. The general purpose of this is to allow a region (or tab) that can be more easily gripped by a patient for removing or detaching the patient interface17from the dermal patch. For example, the backing2004may also comprise of such a corner region.

The two-part releasable attachment or connection arrangement551may comprise a hook and loop material (such as Velcro™), a magnet or an array of magnets disposed on the respective patches with the poles suitably arranged, an adhesive arrangement that is activated when the patches are urged together, or any other suitable releasable coupling. The interface side of the dermal patch550may have one of a hook or a loop material, and the patient side of the patient interface patch552may have the other of the hook or loop material, such that the dermal and patient interface patches are releasably attachable to each other.

In this configuration, the patient sensor29mentioned above is still located on a side arm31of the body32of the nasal cannula30in the same region as the facial pad.

In order to provide power to and receive data from the patient sensors29, one or more wires46connect the patient sensors29to the controller13. The wires46may be attached to, or mounted on or in, the body32, the interface connector35, and/or the gases inlet conduit62of the nasal cannula30, see for exampleFIGS.16to20

There are a number of ways in which the wires46can be attached to, or mounted on or in, the body32, the interface connector35, and/or the gases inlet conduit62, in accordance with this disclosure. For example, in some configurations, the wires46are embedded into the material of the body32and the gases inlet conduit62of the nasal cannula30. In some configurations, the wires46are attached to the inner surface of the body32, the interface connector35and the gases inlet conduit62. In some configurations, the wires46are attached to the outer surface of the body32, the interface connector35and the gases inlet conduit62. In some configurations, a mesh wrap comprising interwoven filaments surrounds the body32, the interface connector35and/or the gases inlet conduit62. In some configurations at least a portion of the filaments are at least partially metal. In some configurations at least a portion of the filaments are at least partially plastic. In some configurations at least a portion of the filaments are at least partially made of a natural fibre. In some configurations, the wires46are interwoven with the filaments of the mesh wrap. Alternatively, any two or more of these configurations may be combined. For example, the wiring46may be embedded into the material of the body32and then attached to the outer surface of the interface connector35and the gases inlet conduit62.

In configurations in which the interface connector35is removably attached to the body32, the interface connector35and the body32each comprise one or more electrical contacts to allow the formation of an electrical connection between the wires46on the interface connector35and the body32when the nasal cannula30is assembled. The wires46in the interface connector35pass into the gases inlet conduit65, with the opposing end of the gases inlet conduit62further comprising a connector comprising additional electrical contacts that correspond to electrical contacts on a connector of the inspiratory conduit16. The electrical contacts of the gases inlet conduit62and the inspiratory conduit16may be configured such that an electrical connection is formed automatically if the two components are pneumatically connected. For example, the electrical contacts of the gases inlet conduit62and the inspiratory conduit16may be configured such that the pneumatic connection cannot be formed without the electrical connection also being formed. Additionally, the electrical contacts of the gases inlet conduit62and the inspiratory conduit16may be configured such that electrical connection cannot be formed without the pneumatic connection also being formed. The corresponding electrical contacts may be configured to contact each other when the pneumatic connection is formed. The corresponding electrical contacts may comprise planar surfaces. Additionally, or alternatively, the electrical contacts may comprise a pin and socket arrangement. This configuration offers the advantage of further reducing the setup time of the respiratory support system by not further requiring that a separate electrical connection be formed between the respiratory support apparatus10and the patient sensor29.

As the electrical contacts of the gases inlet conduit62and the inspiratory conduit16may form an electrical connection automatically when the two components are connected pneumatically, the electrical contacts of the gases inlet conduit may non-moveable relative to the remainder of the connector.

In a further configuration, the patient interface17comprises one or more patient sensors29located on a sensor arm47, which will now be described with reference toFIGS.16to25. The sensor arm47may be relatively rigid, in that it cannot be easily deformed by the user. Alternatively, the sensor arm47may be resiliently deformable, in that it can be easily deformed by the user. The sensor arm47may have a patient contacting surface configured to contact the patient's skin. The patient contacting surface may be coated with an adhesive to ensure contact between the sensor arm47and the patient's skin.

The sensor arm47comprises a patient sensor29such as a pulse oximeter. The pulse oximeter may be a reflectance pulse oximeter comprising an emitter29aand a receiver29bas described above. Unless otherwise stated, the wiring46for the sensor arm47configurations is substantially the same as described above for the previous configurations without the sensor arm47.

In the configurations shown inFIGS.16and17, the sensor arm47is located on the lower side of the nasal cannula30. The sensor arm47may be located near the centre of the nasal cannula30. The position and dimensions of the sensor arm47are designed such that the patient sensors29contact the patient's upper lip whilst the nasal cannula30is in use. Alternatively, in the configurations shown inFIGS.18and19, the position and dimensions of the sensor arm47are designed such that the patient sensors29contact the patient's skin above their upper lip whilst the nasal cannula30is in use.

In a further configuration, the sensor arm47extends from a sensor mount48, which will now be described in detail with reference toFIGS.20to25. In the configurations shown inFIGS.20and21, the nasal cannula30further comprises a sensor mount48located on a portion of one or more of the straps, such as one of the front straps50. The sensor mount48may be fixedly attached to one of the front straps50. Alternatively, the sensor mount48may be removably attached to one of the front straps50. Additionally, or alternatively, the sensor mount48may be slidably attached to one of the front straps50. Alternatively, the sensor mount48may be removably attached to the gases inlet conduit62. Additionally, or alternatively, the sensor mount48may be slidably attached to the gases inlet conduit62. The slidable pulse oximeter can be slid along the face to locate the sensor in an appropriate location on a face to get a pulse oximeter (i.e. SpO2) reading. For example the sensors may be located in a cheek region.

The sensor arm47extends from the sensor mount48and is configured to contact the patient's skin whilst the nasal cannula30is in use. The sensor arm47may be arranged such that it extends from the sensor mount48perpendicular to the front strap50. In a configuration in which the sensor mount48is slidably mounted to one of the front straps50, this direction is perpendicular to the direction of travel of the sensor mount48.

The sensor arm47may be fixedly attached to the sensor mount48.

Alternatively, as shown inFIGS.22and23, the sensor arm47may be slidably attached to the sensor mount48. As shown inFIG.22, the sensor arm47may be able to slide in the same direction as which the front strap50extends. Additionally, or alternatively, the sensor arm47may be able to slide in a direction perpendicular to the direction in which the sensor arm47extends from the sensor mount48. Additionally, or alternatively, as shown inFIG.23, the sensor arm47may be able to slide in a direction perpendicular to the direction on which the front strap50extends. Additionally, or alternatively, the sensor arm47may be able to slide in the same direction as which the sensor arm47extends from the sensor mount48.

Additionally, or alternatively, as shown inFIG.24, the sensor arm47may be rotatably mounted to the sensor mount48. Additionally, or alternatively, as shown inFIG.25, the sensor arm47may be able to extend and retract telescopically relative to the sensor mount48.

By having the sensor mount48removably and/or slidably attached to one of the front straps50, and/or having the sensor arm47movably attached to the sensor mount using one or more of the techniques described above, the user is able to adjust the position the of the patient sensor as needed, while still being able to set up the system relatively quickly. Additionally, the system allows the user to adjust the patient sensor as required while still benefitting from the integrated electrical and pneumatic connectors of the nasal cannula30. The sensor and sensor mount is adjustable to allow the sensor to be located on the face of the patient to get an accurate SpO2measurement.

In a further configuration, the sensor arm47is replaced by a sensor clip, thereby allowing the patient sensor29to be clipped onto a part of the patient, such as the ear lobe. In this configuration a transmissive pulse oximeter is used instead of a reflectance pulse oximeter.

A further possible configuration involving a wire coil will now be described in relation toFIGS.26to28. In this configuration, the sensor mount48is replaced by a wire coil49. The wiring46leading up to the wire coil49is substantially the same as the previously described configuration.

As shown inFIGS.26to29, the sensor arm47may be connected to the wire coil49by a secondary wire46a. The sensor arm47may have any of the features described for the sensor arm47in the previous configuration. In this particular configuration, the sensor arm47may have an adhesive surface to allow it to adhere to the patient's skin. This arrangement of the sensor allows for the sensor29to be located in the temporal region of the face or on the frontal region of the forehead or on the mental region near the lower lip, where there are blood vessels that can be used to get blood oxygen (i.e. SpO2) readings. The structure of the wire coil provides adjustability of the sensor29position to a region on the fac where there are larger blood vessels useful for obtaining SpO2 readings.

As shown inFIG.26, the sensor arm47starts in an initial position, in which the sensor arm is located on or next to the wire coil49, with the secondary wire46abeing substantially completely retracted into the wire coil49. As shown inFIGS.27and28, the sensor arm47can then be moved to a location on the patient's skin such that patient sensor29can begin measuring the one or more patient parameters. As the sensor arm47is moved onto the patient's skin, the secondary wire46auncoils as much as necessary from the wire coil49. This arrangement provides the user with added flexibility in their placement of the patient sensor29. For example,FIGS.27and20Cillustrate examples of how the patient sensor29can be placed on the patient's cheek or temple depending on the preference of the user and/or patient.

The secondary wire46ais able to retract into the wire coil49. The wire coil49may have a coil spring mechanism. A coil spring mechanism allows for compact storage of the secondary wire46awithout requiring much input by the user when the recoiling needs to be performed. The coil spring mechanism may be configured to automatically retract the secondary wire46a. This is advantageous in that there is a reduced chance of the user forgetting to recoil the secondary wire46a. Additionally, automatic retraction means that the only minimum required length of the secondary wire46ais uncoiled, thereby reducing the chance that it becomes tangled with other components. Alternatively, coil spring mechanism may be configured to only retract the secondary wire46awhen the user actuates a component, such as a switch, button, lever, or the like. This is advantageous in that there is no tension in the secondary wire46aduring use, thereby potentially increasing patient comfort and reducing the chance of the sensor arm47becoming dislodged.

The wire coil49may be fixedly attached to one of the front straps50. Alternatively, the wire coil49may be removably mounted to one of the front straps50, such that it can removed and replaced on a separate section of one of the front straps50and/or on a sperate part of the nasal cannula30by use of a clip or any other suitable connector. To facilitate this, the wire coil49may have a second coil spring mechanism corresponding to a second wire that connects the wire coil49to the wire46of the nasal cannula30. The second coil spring mechanism may have any of the same features as the first coil spring mechanism.

In a further configuration, the wire coil49may be fixedly or removably attached to the gases inlet conduit62as shown inFIGS.30to32. In this configuration, the wire coil49may connect to the wire46as it passes through the gases inlet conduit62. This configuration may be more suitable if the user wishes to attach the patient sensor29to the patient's neck or chest. The coil49allows for adjustability which assists in getting more accurate SpO2 readings by moving the sensor29in various locations.

The maximum length of the secondary wire46ais set based on the expected maximum necessary length. The expected maximum necessary length depends on the expected locations at which the user might wish to place the patient sensor29. For example, a longer maximum length may be provided in order allow user to attach the patient sensor29to the patient's chest, upper back, or shoulders. In one configuration the secondary wire46ahas a maximum length of about 300 mm.

In a further configuration, the sensor arm47is replaced by a sensor clip, thereby allowing the patient sensor29to be clipped onto a part of the patient, such as the ear lobe. In this configuration a transmissive pulse oximeter is used instead of a reflectance pulse oximeter. This variation may be applied to any of the wire coil configurations described above.

A further configuration in which the patient sensor29is integrated into the head securement assembly will now be described with reference toFIGS.33to36.

Referring now toFIGS.33, a configuration is shown in which a patient sensor29is incorporated into a forehead strap53c. The patient sensor29may be a reflectance type pulse oximeter as previously described. The forehead strap53cmay be made of an elastic material, thereby helping to stabilize the head securement assembly as well as to maintain contact between the patient sensor29and the patient's forehead. In this configuration the wire46continues from the side arms31into the head securement assembly to the location of the patient sensor29. In configurations in which the side arms31are removably attached to the head securement assembly, the head securement assembly and side arms31comprise corresponding electrical contacts.

In the previous listed configurations, the patient interface17is a nasal cannula30. Referring now toFIG.34, a configuration is shown in which the patient interface17is a sealed nasal mask80. Alternatively, the patient interface may be another type of sealed interface, such as an oral mask, a full face mask, a nasal pillows interface, or the like. Sealed interfaces typically utilize a forehead support81, in which the patient sensor29may be located. The patient sensor29may be a reflectance type pulse oximeter as previously described. In this configuration the wire46continues from the patient interface17into the head securement assembly to the location of the patient sensor29. In configurations in which the patient interface17are removably attached to the head securement assembly, the head securement assembly and patient interface17comprise corresponding electrical contacts.

Referring now toFIGS.35and36, configurations are shown in which the patient interface is a tracheostomy interface90. As shown inFIG.35, the patient sensor29may be placed in a neck strap91. Alternatively, the patient sensor29may be paced in a sensing neck band92. The sensing neck band92may be made of an elastic material to promote contact between the patient sensor29and the patient's skin. The wiring46for the patient sensor29may be built into the neck strap91and/or the neck band92, as described for the previous configurations. The patient sensor29may be a reflectance type pulse oximeter as previously described.

The above features of a patient sensor29may be used in conjunction with a nasal cannula substantially as described in our earlier international patent application WO2014/182179 filed 7 May 2014, the entire contents of which are hereby incorporated by reference.

For example, a nasal cannula can be provided as described in WO2014/182179 comprising a body configured to engage with an orifice of the patient and direct the gases flow to said orifice. Such a nasal cannula can comprise part of a respiratory therapy system for example as described with reference toFIGS.1to3. As described with reference toFIGS.3to36, the nasal cannula can be provided with one or more sensors configured to measure a parameter. The one or more sensors are mounted (i.e. positioned) on the nasal cannula. Such embodiments are described in more detail below.

We refer now toFIGS.37to43. These embodiments show a patient interface101configured to deliver breathing gases from a gases supply and humidification source (not shown) to the patient, and headgear200configured to support and retain the patient interface against the patient's face in use. The patient interface101is in the form of a nasal cannula1000that is adapted to couple an inspiratory conduit300and that comprises at least one, but preferably two, nasal prongs111and112configured to fit within the nares of a patient to deliver a flow of gases to the patient. The headgear200is in the form of a head strap200that is preferably adjustable in length to customise the size of the strap to the patient.

The nasal cannula1000comprises a face mount part110(i.e. body) including at least one, but preferably a pair of, tubular nasal prongs111and112, integrally moulded with or removably attached to the face mount part110(i.e. body), and a gases flow manifold part120that is removably attached or integrally moulded to the conduit300. The gases flow manifold part120is insertable into the face mount part from either one of two opposing horizontal directions, i.e. from either left side or the right side. In this manner, the position or location of the gases flow manifold part120is reversible with respect to the face mount part110(i.e. body). In other words, a user may choose to have the manifold part120(and essentially the conduit300extending there-from) extend from either the left side or the right side of the cannula1000depending on what is most convenient, for example depending on which side of the user the gas source or ventilator is located.

The face mount part110is formed from a soft and flexible material such as Silicone or other cannula material known in the art. The nasal prongs111and112are preferably supple and maybe formed from a sufficiently thin layer of Silicone to achieve this property.

The gases flow manifold part120is formed from a relatively harder material such as Polycarbonate, a High-Density Polyethylene (HDPE) or any other suitable plastics material known in the art. The face mount part110provides a soft interfacing component to the patient for comfortably delivering the flow of gases through the nasal prongs111and112, while the gases flow manifold part120fluidly couples the conduit300to the nasal prongs111and112of the face mount part110.

A patient sensor29, such as a pulse oximeter or multiple pulse oximeter sensors, may be located on or in the manifold part120.

The sensors29may be integrated into the manifold part120and therefore may be disposable. Alternatively, the sensors29may be removably mounted on the manifold part120. The manifold part120may have an appropriate recess or receiving port/opening to receive the one or more sensor(s)29. The one or more sensor(s)29may be removable and reusable.

The one or more sensor(s)29may be wireless or wired. The or one or more wires of the sensor(s)29can be routed through the manifold part120, via the inlet122and back to the system controller via the inspiratory conduit300.

The one or more sensor(s) are positioned on the manifold part120so as to position the sensor(s)29in contact with or adjacent the upper lip region e.g. in the oral region of the face. There are a number of blood vessels in the upper lip and the sensor(s)29can be used to determine blood oxygen via contact with or proximity to the upper lip region via the manifold part120.

The manifold part120may be formed from a rigid plastics material as it is received into a soft silicone body of the cannula. The manifold part120being rigid makes it easier to insert the manifold part into the face mount portion and retain the manifold part in its operative position (i.e. inserted within the face mount). The manifold part is inserted into the face mount part and in fluid communication with the prongs to direct gases from the inlet conduit to the prongs. The sensors29located on or in the manifold part being positioned in the face mount part positions the sensor29in a sensing position i.e. the sensor is positioned adjacent or in contact with the upper lip.

A patient's septum and/or columalla is generally quite a sensitive area and can be a source of discomfort when subjected to excessive contact pressure for prolonged periods. The nasal cannula of the present disclosure can alleviate or reduce this pressure by providing a cushioned region of the cannula1000adjacent the patient's septum/columalla. With reference toFIGS.42and43, in an embodiment, the outlet123comprises a pair of opposed recesses or grooves124/125at the outer periphery for forming a dent or dip127in a region that locates adjacent the septum/columalla in use. When coupled to the face mount portion110, this dip127creates a gap between the base portion118and the outlet123of the manifold120. In use, the gap cushions/softens the region of the cannula100directly adjacent the septum/columalla. It disengages the pressure of the harder manifold part120from the septum/columalla and allows the septum/columalla to rest on the soft base of the face mount portion110only.

The base portion118is preferably also formed with a hollowed outer portion and/or dipped outer profile118bbetween the prongs111and112to alleviate pressure at the septum/columalla. The hollowing should be as much as possible without (significantly) compromising the flow delivered to the patient. The dipped portion118bis also preferably complementary to the periphery of the outlet123to maintain an effective seal between the two parts of the cannula.

The pulse oximeter29may be placed in between the prongs111,112on the upper surface of the cannula such that it contacts the septum/columella. For example the pulse oximeter29is positioned within the dipped portion118bbetween the prongs. The recessed manifold is advantageous when the sensor29is positioned between the prongs111,112in order to reduce pressure sores or other pressure injuries due to the sensor29being in contact with the septum/columella. The recessed portion, that is, dip127in the face mount portion110, allows the cannula to deform into the recessed section thereby ensuring sensor contact while alleviating pressure injury. The dip127may therefore be beneficial if the pulse oximeter29is located on the top surface of the base portion118(for example in a position as indicated inFIG.9, between the two prongs111,112).

In the embodiment ofFIGS.37to41, the headgear used to retain the patient interface100against the patient's face comprises a head strap200of a single continuous length and adapted to extend in use along the patient's cheeks, above the ears and about the back of the head.

Primary end portions201and202of the strap200are adapted to releasably connect to respective formations101and102(seeFIG.38Afor example) on either side of the nasal cannula100to hold the cannula100in position during use.

A strap connector230is provided at each of the secondary end portions203/204of the main strap210and the respective end portions203/204of the strap segments220.

Each connector230is provided with a strap connection mechanism at one end to couple to the strap material, and a coupling mechanism at an opposing end to releasably couple the respective end of a similar connector230.

Cannula connectors240are provided at the primary end portions201and202of the main strap210. These connectors240have a similar strap connection mechanism to the strap connectors230of the secondary end portions203and204, but include a clip member, such as a push fit clip241, at an end of the connector240opposing the strap ends. The clip241is configured to releasably couple the respective formation101/102at the side of the cannula110. The clip member241is preferably a bendable part, such as a plastic part, that forms a hinged portion relative to the strap. The clip241is preferably preformed to have a curved shape along its length, such as one with an angle between flat and 20 degrees for example. This curve allows the clip241to fit the contour of the patient's face in the region of the clip241.

Referring toFIGS.40and41, a method of engaging and disengaging each connector240of the head strap200to and from the patient interface110will now be described. Each connector240comprises a clip member241having an elongate connector body242and a lateral projection243at a terminal end of the body242. The lateral projection243comprises an inwardly facing engagement surface243a. The face244of the connector240opposing the face245from which the projection243extends is preferably substantially smooth or planar. The corresponding formation101/102of the cannula110comprises a channel101a/102ahaving entry101b/102band exit101c/102capertures at either end of the channel101a/102a. A peripheral wall of the exit aperture101c/102cdefines an abutment101ci/102ciconfigured to engage with the surface243aof the projection243of the clip member241. A periphery101bi/102biof the entry aperture101b/102bdefines an abutment for engaging a flange246at an opposing end of the body242to the projection243. This acts to limit the extent of insertion of the connector240into the corresponding channel101a/102a. The flange246may be provided by a terminal end of the strap connection mechanism and/or the sleeve270.

Each section on either side of the head strap200and adjacent the respective primary end portion201/202includes or has applied thereto a cheek support270comprising at least a surface region271for frictionally engaging with the user's face to stabilise the headgear200on the face at the cheek, such as the cheekbone or below or a region thereof, both during coupling of the headgear to the patient interface100and after when in use. The surface region270is preferably of a relatively higher frictional surface material than the remainder of the strap200.

The high friction surface material271is adapted to extend over a portion of the side of a patient's face in use, preferably at or at least substantially towards the patient's cheek, to assist with retaining or stabilising of the patient interface100upon the face of a patient. The high friction surface material, being locatable at the cheek of the user, further assists in keeping a remainder of the head strap200separated from and preferably extending below the eye or the orbit of the eye of the user, so as to prevent obstruction of vision and/or discomfort resulting from the head strap200bridging at or near the eye or eye orbit.

It will be appreciated the high friction surface material271may be adapted to extend over a portion of the side of a patient's face in use, for example, extending from at or near or above the left and right outer upper lips rearwardly and upwardly across the left and right cheeks.

The frictional surface material may be provided in the form of an elongate sleeve270that is configured to receive the respective primary end portion201/202of the strap200. The sleeve270is configured to removably couple (or alternatively be permanently coupled) about the strap200, a section of the strap200and/or a cannula connector240/260at the primary end portion of the strap.

The sleeve270is coupled about the strap210at the primary end portion201/202and also about a portion of the connector240. The strap210extends through a passage272in the sleeve270, as can be seen inFIG.37B. The strap210is adapted to be threaded through this passage and preferably remains free to be stretched or elasticised or extended when in a sleeved configuration. The connector240is substantially housed by the sleeve270or shrouded by the surface region to minimise direct contact with the user's skin thereby improving stability comfort of the headgear200. The clip241extends from an end273of the sleeve270. In another embodiment, the sleeve270can be over-moulded on the connector240and/or the strap210.

Referring toFIG.38A, the sleeve270may be coupled about the connector260extending from the strap210at the primary end portion201/202. In this embodiment the connector260is substantially housed by the sleeve270or shrouded by the surface region to minimise direct contact with the user's skin thereby improving stability and comfort of the headgear200. In other words, the connector260extends fully though the passage272of the sleeve270. The buckle251/252extends from an end274of the sleeve270and the clip261extends from the opposing end273.

The sleeve270may be pre-formed to have a curved shape along its length, such as one with an angle between flat and 20 degrees for example. The curve allows the sleeve270to fit the contour of the patient's face or cheek in the region of the sleeve in use. Alternatively the sleeve270may elastically or non-elastically deform to take on the shape of a curved sleeve upon engagement with the primary end portion201/202or connector260of the head strap200.

The sleeve270provides a surface region271of relatively higher frictional surface material for frictionally engaging with the user's face or facial skin. This surface region271is to be positioned for frictional engagement with the facial cheek skin of a user. The surface region271is at least localised to the strap or the section of strap which is to be positioned upon the cheeks of a user. The surface region271provided with the relatively higher frictional surface material is preferably of a material that is smooth and comfortable on the skin of the patient. The sleeve270or at least the surface region271is therefore formed from a relatively softer material than the connectors240and260.

In one preferred embodiment, the surface region271or the sleeve270is formed from a soft Thermoplastic Elastomer (TPE), but may alternatively be formed from another plastics material such as Silicone, or any other biocompatible materials.

Headgear for other forms of interface in addition to nasal cannula may comprise cheek supports270as described or similar, at or adjacent either side end of straps of headgear of the interface, which connect to the mask, for frictionally engaging with the user's face to stabilise the mask on the face at the cheeks, and particularly for example direct nasal masks comprising nozzles or pillows which enter or engage the nares of the wearer. Such headgear may again comprise a single head strap adapted to extend in use along the patient's cheeks, above the ears and about the back of the head, with ends comprising clips in any suitable form which couple to the mask on either side (or are permanently attached to the mask).

A patient sensor29, for example in the form of a pulse oximeter, may be provided on the nasal cannula1000ofFIGS.37to41.

The patient sensor29may be provided on nasal cannula1000in accordance with any of the configurations described with reference to the nasal cannula100ofFIGS.1to36.

The patient sensor29may be provided on the headgear200, or on another removable part of the nasal cannula1000that connects to the face mount part110, or the gases flow manifold part120of the nasal cannula1000. In this way, if the face mount part110, and/or the gases flow manifold part120are replaced or disposed of, the patient sensor29can be retained with the headgear200or other removable part, so that the patient sensor29is not disposed of and can be reused. For example, the patient sensor29could be provided on headgear200which is configured to connect to multiple different sizes of face mount part110, and/or gases flow manifold part120. This allows a user to swap or replace parts of the cannula without having to dispose of the patient sensor29.

Referring toFIGS.37to41, the patient sensor29may be provided on sleeve270. Any wiring associated with patient sensor29may extend through passage272of sleeve270, and extend from the end274.

Patient sensor29may be recessed into the face contacting surface271of the sleeve270and may be flush with that face contacting surface271. Patient sensor29may be located in any suitable position along the length of sleeve270, for example adjacent the formations101,102, or adjacent headgear strap210.

Patient sensor29may be permanently mounted on the sleeve, for example the patient sensor29may be overmoulded onto the sleeve270.

Patient sensor29may be removably mounted on the sleeve270so that the patient sensor29can be replaced, or reused if the sleeve270is disposed of. The patient sensor29can be removed, wiped and incorporated into a different cannula having a similar recess in the sleeve270to receive the sensor29. This allows the sensor to be reused for patient's thereby reducing costs to a medical care facility.

Alternatively, the patient sensor29may be provided in a complimentary sensor body that can be permanently or removably mounted on the sleeve270, for example in a corresponding recess on the sleeve270. The recess and complimentary body may be provided with one or more retaining formations configured to retain the body in the recess. The sensor29being incorporated into the sleeve270provide the sensor29in contact with the cheek region e.g. the buccal or temporal regions of the face. There are blood vessels in this area of the face that the sensor can be positioned adjacent and used to detect the blood oxygen.

A patient interface, such as a nasal cannula in accordance with any ofFIGS.37to43, may comprise a plurality of patient sensors29.

For example, the patient interface may comprise multiple sensors29(i.e. multiple pulse oximeters) incorporated into the patient interface. For example, each or at least one sleeve270may have one or a plurality of pulse oximeters29that are positioned on or in the side arm (i.e. sleeve270). The measurements from these multiple sensors29can be averaged by the controller to provide a blood oxygen (SpO2) reading.

Each sleeve270may therefore comprise a single sensor29.

In a further alternative form, each sleeve270(i.e. each side arm) of the cannula may comprise multiple sensors. One, some or all of the plurality of sensors may be removable. Each sleeve270may comprise a plurality of recesses or openings to receive sensors29.

Multiple sensors29can be advantageous, as averaging the measured values can provide for a more accurate SpO2 reading and reduce noise in the sensor readings received by the controller.

Referring toFIG.39, a retention clip280may be provided that comprises a tubular body281for receiving and accommodating a portion of the conduit300therein. A hook282projects from the body281to couple the strap or other component of the headgear200. In this manner the conduit300can be coupled or tethered to the head strap210or headgear200in use. If the conduit300is pulled, the force will be exerted onto the head strap210and not directly on the cannula100. This relocation of force will reduce the likelihood of the prongs111and112of the cannula100flicking out of the patient's nostrils.

One or more tethering points for connecting the clip280may be available on the headgear200, with preferably at least two symmetric tethering points on either side of the headgear to increase usability.

It will also be appreciated the retention clip280may be removeable from or may be a permanent fitting on the gas supply tube300.

The retention clip280may be connected or retained to a part of the patient interface, such as for example a part of an interface which provides for a relatively more rigid region (such as to facilitate support of the gas supply tube item300).

The retention clip280may also be positioned or affixed at a particular location on the gas supply tube item300, for example a predetermined location may be provided which holds the retention clip280in place.

The retention clip280may be configured to retain the wiring of the patient sensor29, to secure the wiring against the conduit300. The patient sensor wiring can therefore extend in parallel with the longitudinal axis of the conduit300.

The conduit300may be provided with one or more sensor wires, for example in the wall of the conduit, or extending through the bore of the conduit. The one or more sensor wires may be configured to be electrically coupled to the patient sensor29.

Such electrical coupling could be provided by a physical electrical coupling, such as via an electrical connector, between wiring of the patient sensor29and the one or more sensor wires in the conduit300.

Such electrical coupling could be provided via an inductive coupling. For example patient sensor wiring may extend along sleeve270and/or may be provided in the face mount part110, and/or the gases flow manifold part120of the cannula1000. Conduit wiring may extend to a position at or adjacent an end of the conduit300, where the conduit300is connected to the inlet of the nasal cannula. The conduit300and the cannula1000may be provided with inductive couplers configured to electrical couple the conduit300to the patient sensor wiring.

Such an arrangement would remove or reduce the need for a physical electrical connector or the like, and the need for one or more exposed electrical contacts. Such an arrangement would also remove or reduce the number of connections needing to be made by a user in use of the nasal cannula1000. For example if the patient sensor29and headgear200were to be reused, the user would not have t physically disconnect the patient sensor wiring from the conduit300.

The conduit300may be a heated or an unheated conduit. The conduit may be an extension of any desired length.

Where reference is used herein to directional terms such as ‘up’, ‘down’, ‘forward’, ‘rearward’, ‘horizontal’, ‘vertical’ etc., those terms refer to when the apparatus is in a typical in-use position, and are used to show and/or describe relative directions or orientations.

The terms “approximately,” “about,” and “substantially” as used herein represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, in some embodiments, as the context may permit, the terms “approximately”, “about”, and “substantially” may refer to an amount that is within less than or equal to 10% of, within less than or equal to 5% of, and within less than or equal to 1% of the stated amount.

Depending on the embodiment, certain acts, events, or functions of any of the algorithms, methods, or processes described herein can be performed in a different sequence, can be added, merged, or left out altogether (for example, not all described acts or events are necessary for the practice of the algorithms). Moreover, in certain embodiments, acts or events can be performed concurrently, for example, through multi-threaded processing, interrupt processing, or multiple processors or processor cores or on other parallel architectures, rather than sequentially.

It should be noted that various changes and modifications to the presently described embodiments described herein will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the disclosed apparatus and systems and without diminishing its attendant advantages. For instance, various components may be repositioned as desired. It is therefore intended that such changes and modifications be included within the scope of the disclosed apparatus and systems. Moreover, not all of the features, aspects and advantages are necessarily required to practice the disclosed apparatus and systems. Accordingly, the scope of the disclosed apparatus and systems is intended to be defined only by the claims that follow.