VENTILATORY SUPPORT SYSTEM
RELATED APPLICATIONS
[0001] This application claims priority from Australian Provisional Patent Application No. 2023903001, filed September 18, 2023, and Australian Provisional Patent Application No. 2024900989, filed April 9, 2024, the entire contents of which are incorporated by reference.
FIELD
[0002] The disclosure relates to ventilatory support systems, breathing circuits, apparatuses, and methods. Particularly, but not exclusively, for aerating the upper respiratory tract of a patient during invasive ventilation.
BACKGROUND
[0003] A mechanical ventilator is a medical device that may be used to provide respiratory support to a patient by moving breathable air, oxygen, or a mixture of gases into and out of the lungs. Mechanical ventilators use positive pressure to push air into the lungs to partially or completely support the lung function of the patient. The ventilator may include one or more of a valve or a flow generator to provide a controlled flow of pressurized gases to the patient. Settings of the mechanical ventilator may be adjusted to meet the specific needs of the patient. The mechanical ventilator may:
• provide gases to the lungs of the patient;
• help remove expiratory gases, including carbon dioxide (CO2), from the lungs; or
• provide positive pressure to keep the alveoli (air sacs) in the lungs from collapsing.
[0004] The gases may be delivered to the patient non-invasively or invasively. Invasive ventilation may be preferred or required in some circumstances. For example, to ensure adequate ventilation and oxygenation of a patient that is in cardiac or respiratory arrest, experiencing severe respiratory failure, sedated, or undergoing a surgical procedure.
[0005] In non-invasive ventilation, gases are supplied to one or more of the nose or mouth of the patient by a non-invasive patient interface. The non-invasive patient interface may be a total face mask, a full face mask, a nasal face mask, an oral face mask, nasal pillows interface, or a nasal cannula, for example. [0006] In invasive ventilation, the gases are supplied to the patient by an invasive patient interface inserted, at least in part, within the trachea or pharynx, e.g., laryngopharynx, of the patient by a medical or surgical procedure such as intubation or tracheotomy. The invasive patient interface bypasses the upper respiratory tract of the patient. The invasive patient interface, e.g., an endotracheal tube (ETT), may include a cuff which is inflated after insertion to isolate at least part of the lower respiratory tract of the patient from at least part of the upper respiratory tract. And from ambient air. The invasive patient interface may be an oral endotracheal tube inserted into the trachea or a laryngeal mask inserted into the pharynx through the patient's mouth (oral intubation), a nasal endotracheal tube inserted into the trachea through the patient's nose (nasal intubation), or a tracheostomy tube inserted into the patient's trachea through a stoma in the patient's neck (tracheotomy), for example.
SUMMARY
[0007] In a first aspect, a ventilatory support system for providing ventilatory support to a patient may include: a first gas source configured to generate a first flow of gases, a first patient interface pneumatically coupled with the first gas source and configured to receive the first flow of gases from the first gas source for supply to at least part of a lower respiratory tract of the patient, a second gas source configured to generate a second flow of gases, and a second patient interface pneumatically coupled with the second gas source and configured to receive the second flow of gases from the second gas source for supply to at least part of an upper respiratory tract of the patient.
[0008] Ventilatory support systems according to the first aspect may advantageously aerate the upper respiratory tract with the second flow of gases, mitigating or avoiding stagnancy during invasive ventilation.
[0009] The first patient interface may include an invasive patient interface.
[0010] The first patient interface may be configured to at least partially isolate at least part of the lower respiratory tract of the patient from at least part of the upper respiratory tract of the patient.
[0011] The first patient interface may include one or more of: an oral endotracheal tube, a nasal endotracheal tube, a tracheostomy tube, or a laryngeal mask. [0012] The second patient interface may be, or include, a non-invasive patient interface.
[0013] The second patient interface may be, or include, a nasal patient interface or an oral patient interface.
[0014] The second patient interface may be, or include: a nasal face mask, a nasal pillows interface, a nasal cannula, an intranasal tube, an oral face mask, an intraoral tube, or an intraoral mask.
[0015] The second patient interface may be, or include, a non-sealing patient interface.
[0016] The second patient interface may be, or include, a non-sealing nasal cannula.
[0017] The second patient interface may be, or include, a sealing patient interface.
[0018] The second patient interface may be, or include, an intraoral mask.
[0019] The first patient interface may include an oral endotracheal tube and the second patient interface may include an intraoral mask, wherein the intraoral mask may include a mouth guard configured to be at least partially inserted within an oral cavity of the patient, seal a mouth of the patient, and envelop the oral endotracheal tube, and an intraoral tube configured to convey the second flow of gases to ventilate a nasopharynx, an oropharynx, and a laryngopharynx of the patient.
[0020] The first gas source may include a mechanical ventilator.
[0021] The system may be configured to generate a bi-directional gas flow in at least part of the lower respiratory tract of the patient.
[0022] The second gas source may include a blower configured to generate the second flow of gases from ambient air.
[0023] The system may be configured to generate a bi-directional gas flow in at least part of the upper respiratory tract of the patient.
[0024] The system may be configured to generate a uni-directional gas flow in at least part of the upper respiratory tract of the patient.
[0025] The second gas source may include a nasal high flow device configured to provide nasal high flow. The high flow rates, e.g., above about 15 l/min, 20 l/min, or 25 l/min, may advantageously agitate of move the gases in the upper respiratory tract, helping to aerate the upper respiratory tract. [0026] The first gas source and the second gas source may be pneumatically isolated from one another.
[0027] The first gas source and the second gas source may be pneumatically coupled, wherein: the first gas source is configured to supply the first flow of gases to the second gas source to form, at least in part, the second flow of gases; and/or the second gas source is configured to supply the second flow of gases to the first gas source to form, at least in part, the first flow of gases.
[0028] The system may be configured so that the first flow of gases is not supplied to the upper respiratory tract of the patient.
[0029] The system may be configured so that the second flow of gases is not supplied to the lower respiratory tract of the patient.
[0030] The system may include one or more of: a first humidifier configured to heat and humidify the first flow of gases, or a second humidifier configured to heat and humidify the second flow of gases.
[0031] The system may include a humidifier configured to heat and humidify the second flow of gases, wherein the humidifier is integrated with the second gas source. Humidifying the second flow of gases may advantageously help reach, or maintain, homeostasis, and/or mitigate desiccation of the upper respiratory tract.
[0032] The first gas source and the second gas source may be configured to be controlled independently of one another.
[0033] The first gas source may be configured to generate the first flow of gases based, at least in part, on the second flow of gases generated by the second gas source, and/or the second gas source may be configured to generate the second flow of gases based, at least in part, on the first flow of gases generated by the first gas source.
[0034] The first gas source may be configured to synchronize the first flow of gases with the second flow of gases, and/or the second gas source may be configured to synchronize the second flow of gases with the first flow of gases.
[0035] The second gas source may be configured to synchronize the second flow of gases with a breathing cycle of the first gas source. [0036] The first gas source and the second gas source may be configured to communicate with each other, wherein: the first gas source is configured to sense one or more properties of one or more of the second gas source, the second flow of gases, or the patient; and/or the second gas source is configured to sense one or more properties of one or more of the first gas source, the first flow of gases, or the patient.
[0037] The first gas source may be configured to control the first flow of gases based, at least in part, on one or more of: a volume of the first flow of gases, a pressure of the first flow of gases, or spontaneous breathing of the patient.
[0038] The second gas source may be configured to control the second flow of gases based, at least in part, on a target flow rate.
[0039] The target flow rate may be constant throughout an inspiratory phase and an expiratory phase of a breathing cycle.
[0040] The target flow rate may vary between an inspiratory phase and an expiratory phase of the breathing cycle.
[0041] The target flow rate may be: constant throughout at least part of the inspiratory phase of the breathing cycle, and/or constant throughout at least part of the expiratory phase of the breathing cycle.
[0042] The system may include a first breathing circuit configured to pneumatically couple the first gas source and the first patient interface.
[0043] The first breathing circuit may include: an inspiratory limb configured to convey the first flow of gases from the first gas source towards the first patient interface, and an expiratory limb configured to convey a flow of expiratory gases expired by the patient from the first patient interface to the first gas source.
[0044] The first breathing circuit may include a filter configured to pneumatically couple the expiratory limb and a gases return inlet of the first gas source, and to filter the flow of expiratory gases. [0045] The first breathing circuit may include one or more of: a Y-piece configured to pneumatically couple the inspiratory limb, the expiratory limb, and the first patient interface; or an interface conduit configured to pneumatically couple the first patient interface with the Y-piece, or the inspiratory limb and the expiratory limb.
[0046] The first breathing circuit may include one or more of: a humidifier chamber configured to be located in a flow path of the first flow of gases, and to contain a volume of water to humidify the first flow of gases; or a humidifier supply conduit configured to pneumatically couple the first gas source and the humidifier chamber.
[0047] The system may include a second breathing circuit configured to pneumatically couple the second gas source and the second patient interface.
[0048] The second breathing circuit may include a delivery conduit configured to convey the second flow of gases from the second gas source towards the second patient interface.
[0049] The second breathing circuit may include an inspiratory limb configured to convey the second flow of gases between the second gas source and the second patient interface, and an expiratory limb configured to convey the second flow of gases between the second gas source and the second patient interface.
[0050] In a second aspect, a breathing circuit kit for use in a ventilatory support system configured to provide ventilatory support to a patient may include: a first breathing circuit configured to convey a first flow of gases received from a first gas source of the ventilatory support system towards a first patient interface of the ventilatory support system for supply to at least part of a lower respiratory tract of the patient; and a second breathing circuit configured to convey a second flow of gases received from a second gas source of the ventilatory support system towards a second patient interface of the ventilatory support system for supply to at least part of an upper respiratory tract of the patient.
[0051] The first breathing circuit may include: an inspiratory limb configured to convey the first flow of gases from the first gas source towards the first patient interface, and an expiratory limb configured to convey a flow of expiratory gases expired by the patient from the first patient interface towards the first gas source.
[0052] The kit may include a filter configured to pneumatically couple the expiratory limb and a gases return inlet of the first gas source, and to filter the flow of expiratory gases.
[0053] The first breathing circuit may include one or more of: a Y-piece configured to pneumatically couple the inspiratory limb, the expiratory limb, and the first patient interface; or an interface conduit configured to pneumatically couple the first patient interface with the Y-piece, or the inspiratory limb and the expiratory limb.
[0054] The first breathing circuit may include one or more of: a humidifier chamber configured to be located in a flow path of the first flow of gases, and to contain a volume of water to humidify the first flow of gases; or a humidifier supply conduit configured to pneumatically couple the first gas source and the humidifier chamber.
[0055] The second breathing circuit may include a delivery conduit configured to convey the second flow of gases from the second gas source towards the second patient interface.
[0056] The second breathing circuit may include an inspiratory limb configured to convey the second flow of gases between the second gas source and the second patient interface, and an expiratory limb configured to convey the second flow of gases between the second gas source and the second patient interface.
[0057] The first breathing circuit and the second breathing circuit may be pneumatically isolated from each other.
[0058] The kit may include the first patient interface.
[0059] The first patient interface may include an invasive patient interface. [0060] The first patient interface may be configured to seal at least part of the lower respiratory tract of the patient from at least part of the upper respiratory tract of the patient.
[0061] The first patient interface may include one or more of: an oral endotracheal tube, a nasal endotracheal tube, a tracheostomy tube, or a laryngeal mask.
[0062] The kit may include the second patient interface.
[0063] The second patient interface may be, or include, a non-invasive patient interface.
[0064] The second patient interface may be, or include, one or more of: a nasal face mask, a nasal pillows interface, a nasal cannula, an intranasal tube, an oral face mask, an intraoral tube, or an intraoral mask.
[0065] The second patient interface may include a non-sealing patient interface.
[0066] The second patient interface may include a non-sealing nasal cannula.
[0067] The second patient interface may include a sealing patient interface.
[0068] The second patient interface may include an intraoral mask.
[0069] The first breathing circuit and the second breathing circuit may be packaged together in sealed packaging.
[0070] Breathing circuit kits according to the second aspect may advantageously facilitate circulation of gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation.
[0071] In a third aspect, an aeration device for use in a ventilatory support system, wherein the ventilatory support system comprises a primary gas source configured to provide a primary flow of gases for invasive ventilation of at least part of a lower respiratory tract of a patient, may include: a flow generator configured to generate a secondary flow of gases for supply to at least part of an upper respiratory tract of the patient during the invasive ventilation; and a controller configured to determine a breathing phase of one or more of the primary gas source, the primary flow of gases, or the patient, and to control operation of the flow generator based, at least in part, on the breathing phase. [0072] The aeration device may include a communications module, and the controller may be configured to determine the breathing phase of the primary gas source by communicating with the primary gas source via the communications module.
[0073] The aeration device may include a sensor configured to sense one or more properties of one or more of the primary gas source, the primary flow of gases, or the patient.
[0074] The sensor may comprise one or more of: a flow rate sensor configured to sense a flow rate of the primary flow of gases, or a pressure sensor configured to sense a pressure of the primary flow of gases.
[0075] The controller may be configured to control the flow generator to vary a flow rate of the secondary flow of gases between an inspiratory phase and an expiratory phase of the primary gas source.
[0076] The controller may be configured to control the flow generator to generate the secondary flow of gases at: a first flow rate during at least part of an inspiratory phase, and/or a second flow rate during at least part of an expiratory phase.
[0077] The controller may be configured to synchronize: the first flow rate with respect to the inspiratory phase, and/or the second flow rate with respect to the expiratory phase.
[0078] The first flow rate and the second flow rate may differ.
[0079] The first flow rate may be constant throughout at least part of the inspiratory phase, and/or the second flow rate may be constant throughout at least part of the expiratory phase.
[0080] Aeration devices according to the first aspect may advantageously circulate gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation.
[0081] In a fourth aspect, a method for providing ventilatory support to a patient may include: supplying a first flow of gases to at least part of a lower respiratory tract of the patient, and supplying a second flow of gases to at least part of an upper respiratory tract of the patient.
[0082] The method may include supplying the first flow of gases and the second flow of gases simultaneously.
[0083] The method may include supplying the first flow of gases to the lower respiratory tract by bypassing the upper respiratory tract of the patient.
[0084] The method may include supplying the first flow of gases to the patient via an invasive patient interface.
[0085] The method may include inserting the invasive patient interface by intubating the patient.
[0086] The method may include inserting the invasive patient interface through a stoma in a neck of the patient.
[0087] The method may include forming the stoma by performing a tracheotomy on the patient.
[0088] The method may include supplying the second flow of gases to one or more of a nose or a mouth of the patient.
[0089] The method may include supplying the second flow of gases to one of the nose or the mouth of the patient, and venting the second flow of gases from the other of the nose or the mouth of the patient.
[0090] The method may include supplying the second flow of gases to the patient via a non-invasive patient interface.
[0091] The method may include fitting the non-invasive patient interface to the patient.
[0092] The method may include sealing at least part of the lower respiratory tract of the patient from at least part of the upper respiratory tract of the patient.
[0093] The method may include isolating at least part of the lower respiratory tract of the patient from at least part of the upper respiratory tract of the patient by inflating a cuff of an invasive patient interface within a trachea or pharynx of the patient. [0094] The method may include supplying the second flow of gases comprising as a nasal high flow.
[0095] In some examples, the first flow of gases and the second flow of gases may be pneumatically isolated from one another.
[0096] In some examples, the first flow of gases is not supplied to the upper respiratory tract of the patient.
[0097] In some examples, the second flow of gases is not supplied to the lower respiratory tract of the patient.
[0098] The method may include the first flow of gases forming at least part of the second flow of gases, and/or the second flow of gases forming at least part of the first flow of gases.
[0099] The method may include humidifying one or more of the first flow of gases or the second flow of gases.
[0100] The method may include controlling the first flow of gases and the second flow of gases independently of one another.
[0101] The method may include: determining a breathing phase of one or more of the patient, the first flow of gases, or a gas source configured to supply the first flow of gases; and supplying the second flow of gases based, at least in part, on the breathing phase.
[0102] The method may include supplying the second flow of gases at: a first flow rate during at least part of an inspiratory phase, and/or a second flow rate during at least part of an expiratory phase.
[0103] The method may include supplying the first flow of gases based, at least in part, on one or more of: a volume of the first flow of gases, a pressure of the first flow of gases, or spontaneous breathing of the patient. [0104] The method may include supplying the second flow of gases based, at least in part, on a target flow rate for the second flow of gases.
[0105] The method may include controlling inflation of a cuff of an invasive patient interface through which the first flow of gases is supplied to at least part of the lower respiratory tract of the patient.
[0106] The method may include: inflating the cuff for at least part of an inspiratory phase, and deflating the cuff for at least part of an expiratory phase.
[0107] Methods according to the fourth aspect may advantageously circulate gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation.
[0108] In a fifth aspect, a method for controlling a gas source configured to supply a flow of gases to at least part of an upper respiratory tract of a patient, while the patient receives ventilatory support from a further gas source, the further gas source configured to supply a further flow of gases to at least part of a lower respiratory tract of the patient, the method performed by a controller of the gas source, may include: determining a breathing phase of one or more of the further gas source, the further flow of gases, or the patient; and controlling a flow rate of the flow of gases based, at least in part, on the breathing phase.
[0109] Methods according to the fifth aspect may advantageously circulate gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation.
[0110] In a sixth aspect, a method for providing gases support to a patient may include supplying a flow of gases to at least part of an upper respiratory tract of the patient while the patient is intubated and undergoing invasive ventilation, to circulate gases within the upper respiratory tract of the patient.
[0111] The method may include generating the flow of gases from ambient air and a supplementary gas. The supplementary gas may be, or include, carbon dioxide.
[0112] The method may include supplementing the ambient air with the supplementary gas for part of a breathing cycle. [0113] The method may include supplementing the ambient air with the supplementary gas for part of an expiratory phase of the breathing cycle.
[0114] Methods according to the sixth aspect may advantageously circulate gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation.
[0115] In a seventh aspect, a mouth guard is provided for use in a ventilatory support system configured to provide ventilatory support to a patient, the mouth guard configured to: seal a mouth of the patient, and envelop both an oral endotracheal tube configured to ventilate lungs of the patient, and an intraoral tube configured to ventilate a nasopharynx, an oropharynx, and a laryngopharynx of the patient.
[0116] The mouth guard may include an upper portion, a central portion, and a lower portion, each of the upper portion, the central portion, and the lower portion configured to be removably engaged with another of the upper portion, the central portion, and the lower portion.
[0117] The central portion may be configured to envelop both the oral endotracheal tube and the intraoral tube.
[0118] Mouth guards according to the seventh aspect may advantageously facilitate circulation of gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation.
[0119] In an eighth aspect, an aeration device is provided for use in a ventilatory support system, the ventilatory support system comprising a primary gas source configured to provide a primary flow of gases for invasive ventilation of at least part of a lower respiratory tract of a patient, and the aeration device may include: an inlet module, the inlet module comprising : an air inlet for a flow of air, and a carbon dioxide inlet for a flow of carbon dioxide; and a flow generator configured to generate a secondary flow of gases for supply to at least part of an upper respiratory tract of the patient during the invasive ventilation, from the flow of air and the flow of carbon dioxide. [0120] The flow generator may be configured to generate the secondary flow of gases from: the flow of air during at least part of an inspiratory phase, and both the flow of air and the flow of carbon dioxide during at least part of an expiratory phase.
[0121] Aeration devices according to the eighth aspect may advantageously circulate gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation, and/or mimic, at least in part, the natural physiology and breathing of a healthy human.
[0122] In a ninth aspect, a method of providing ventilatory support to a patient may include providing a flow of gases to one or more of a naris or a mouth of the patient to circulate gases within an upper respiratory tract of the patient while the patient is receiving ventilatory support from a mechanical ventilator.
[0123] Methods according to the ninth aspect may advantageously circulate gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation.
[0124] In a tenth aspect, a method of aerating an upper respiratory tract of a patient may include providing a flow of gases to the upper respiratory tract of the patient via a nose or a mouth of the patient, wherein the flow of gases is generated by a supplementary gas source and delivered to the nose or the mouth of the patient by a supplementary patient interface, while the patient is receiving ventilatory support to a lower respiratory tract from a primary gas source, wherein homeostasis of the upper respiratory tract is reached and/or maintained during at least a period while the patient is receiving ventilatory support from the primary gas source due to the flow of gases to the upper respiratory tract, wherein the flow of gases provided to the upper respiratory tract is a humidified flow of gases.
[0125] The flow of gases may be humidified to a dew point of about 370 Celsius.
[0126] The patient interface may be, or include, a non-sealing patient interface.
[0127] The supplementary gas source may include a blower and a humidifier enclosed, at least in part, within a common housing.
[0128] Methods according to the tenth aspect may advantageously circulate gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation. [0129] In an eleventh aspect, a method of circulating gases in an upper respiratory tract of a patient may include: generating a flow of gases, humidifying the flow of gases, and delivering the flow of gases to the upper respiratory tract of the patient via a patient interface associated with a nose or a mouth of the patient, while a lower respiratory tract of the patient is ventilated via another patient interface.
[0130] Methods according to the eleventh aspect may advantageously circulate gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation, and/or mimic, at least in part, the natural physiology and breathing of a healthy human.
[0131] In a twelfth aspect, a ventilatory support system for circulating gases in an upper respiratory tract of a patient may include: a first ventilatory support apparatus configured to invasively ventilate the patient, wherein gases from the first ventilatory support apparatus are delivered to a lower respiratory tract of the patient; and a second ventilatory support apparatus configured to provide a humidified flow of gases to the upper respiratory tract of the patient via a patient interface, wherein the second ventilatory support apparatus is pneumatically connected to the patient interface, and the humidified flow of gases is provided to one or more of a nose or a mouth of the patient, wherein homeostasis of the upper respiratory tract is reached and/or maintained during at least a period while the patient is receiving ventilatory support from the first ventilatory support apparatus due to the humidified flow of gases circulating in the upper respiratory tract.
[0132] Ventilatory support systems according to the twelfth aspect may advantageously circulate gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation, and/or mimic, at least in part, the natural physiology and breathing of a healthy human.
[0133] In a thirteenth aspect, a method for providing ventilatory support to a patient may include: supplying a flow of gases to one of a lower respiratory tract or an upper respiratory tract of the patient; receiving the flow of gases from the lower respiratory tract or the upper respiratory tract; supplementing the flow of gases with a supplementary gas; and supplying the flow of gases, including the supplementary gas, to the other of the lower respiratory tract or the upper respiratory tract.
[0134] Methods according to the thirteenth aspect may advantageously circulate gases to mitigate or avoid stagnancy within the upper respiratory tract of a patient during invasive ventilation, and/or mimic, at least in part, the natural physiology and breathing of a healthy human.
[0135] The supplementary gas may include one or more of oxygen, carbon dioxide, heliox, or water vapor.
[0136] In a fourteenth aspect, a mouth guard is able to seal the mouth, enveloping both the endotracheal tube and the tube to ventilate the nasal, oral and laryngopharynx.
[0137] In a fifteenth aspect, a tube ventilates the pharynx allowing the proximal end to be connected to the ventilator and the distal end, an aperture in the pharynx to allow inspiration and expiration and closely mimic normal gaseous circulation in the pharynx.
[0138] In a sixteenth aspect, a mechanism stabilizes the two tubes and the mouth guard to the patient.
[0139] In a seventeenth aspect, a method includes removing the mouth guard and ventilation tube for dental and oral hygiene while leaving the endotracheal tube in place.
[0140] In a eighteenth aspect, a ventilator ventilates the pharynx and synchronizes the cycle and respiratory physiology between this ventilator and an existing lung ventilator.
[0141] In a nineteenth aspect, a ventilator ventilates the lungs below the cuff of an endotracheal tube and the nasal, oral and laryngopharynx above the cuff of the endotracheal tube.
[0142] In a twentieth aspect, a preceding breath or current breath from a lung ventilator is transferred to the pharyngeal ventilator and expired through the pharynx of the current ventilation cycle. [0143] In a twenty-first aspect, further warming and humidifying and additionally adding carbon dioxide to the air of the current inspiration through the nostrils before it is expired through the pharynx and nostrils.
[0144] In a twenty-second aspect, the air inspired through the nostrils may be channeled into a fresh gas source, and if necessary be blended with oxygen for the lung ventilator.
[0145] In a twenty-third aspect, the expired air through the nostrils is vented through a port in the pharyngeal ventilator.
[0146] In an twenty-fourth aspect, the pressure in the cuff of the endotracheal tube may be varied and synchronized with the respiratory cycle to allow secretions to be expelled from the lungs below the cuff to the oropharynx above the cuff while still maintaining the desired lung inflation.
[0147] In a twenty-fifth aspect, ventilation of the respiratory tract above the cuff of an oral endotracheal tube may involve a second tube placed through the mouth to act as a channel through which inspiration is drawn and expiration is expelled to ventilate the nasopharynx. It is envisioned that the morphology of this tube will allow the inspired and expired gases to circulate through the pharynx to mimic natural respiratory gas flow with a closed mouth. The length, shape, diameter, and the number of apertures for the gas flow it the portion of tube in the pharynx may vary accordingly. In addition, when inspired gasses are drawn through this tube in the pharynx, secretions may be sucked into the tube providing an additional method of clearing secretions above the cuff of the endotracheal tube.
[0148] In a twenty-sixth aspect, a mouth guard may straddle and be stabilized by the teeth and gums of the patient, envelop the endotracheal tube and a tube to ventilate the nasopharynx, oropharynx, and laryngopharynx. The mouth guard may create a seal allowing inspiration and expiration of the nasopharynx, oropharynx, and laryngopharynx to occur through the nose of the patient. The mouth guard will ideally be made of a soft material that has properties to minimize the formation of a biofilm and is easily cleaned or replaced daily. The mouth guard may be premanufactured in various sizes, custom made, or a combination. The mouth guard may be able to be removed from the patient's mouth without dislodging the endotracheal tube, to allow oral and dental hygiene. The mouth guard may sit between the buccal surface of the lips and the gums and teeth of the patient. Further the tubes and mouth guard may secure the endotracheal tube to the patient. It is envisaged that there may be one or more apertures and tubes that pass through the mouth guard in addition to the endotracheal tube and tube to ventilate the pharynx. These tubes may be for suction of secretions from the floor of the mouth. [0149] In a twenty-seventh aspect, there is provided a ventilator that ventilates the respiratory tract above the endotracheal tube cuff of a mechanically ventilated patient. The breathing cycle and tidal volumes may mimic the existing device ventilating the patient's lungs below the endotracheal tube cuff. The inspired air may be drawn through the patient's nostrils then warmed and humidified, and after adding carbon dioxide, expired through the same.
[0150] In a twenty-eighth aspect, there is provided a single ventilator that is designed to provide ventilation both above and below the cuff of an endotracheal tube.
[0151] In a twenty-ninth aspect, the inspired air may be drawn though the nares and nasopharynx, but the expired air is the expired tidal volume from the ventilator of the lungs of the patient from the breath preceding or current breath. This will present the pharynx with warmed and humidified air and the oxygen and carbon dioxide concentrations may closely mimic natural processes such as ventilation.
[0152] In a thirtieth aspect, the air inspired through the nostrils may be blended with oxygen if required, warmed, and humidified and used as the inspiratory breath for lung ventilation.
[0153] In a thirty-first aspect, the ventilators may include a mechanism where the cuff of the endotracheal tube is attached to a manometer, the degree of pressure in the cuff may vary with the respiratory cycle allowing inflation or deflation of the cuff. In lung inflation the cuff may be inflated and for parts of expiration the cuff may be partially or completely deflated to allow the passage of lung secretions to be expelled from below the cuff to the oropharynx above the cuff along the pressure gradient. A cough may be simulated similarly, by allowing an intrathoracic pressure to build below the cuff of the endotracheal tube generated by the lung ventilator, followed by a sudden deflation of the cuff simulating the opening of the glottis as occurs with a cough, allowing secretions to be expelled from the lungs.
[0154] Further aspects, features, and/or advantages of the present technology will become apparent from the following detailed description.
BRIEF DISCRIPTION OF THE DRAWINGS
[0155] Non-limiting examples of the present technology will be described in detail below with reference to the accompanying drawings.
[0156] FIG. 1 illustrates a schematic diagram of a ventilatory support system according to an example of the present technology, and gas flows within the ventilatory support system during an expiratory phase. [0157] FIG. 2 illustrates a schematic diagram of the ventilatory support system of FIG.
1, and gas flows within the ventilatory support system during an inspiratory phase.
[0158] FIG. 3 illustrates the second flow of gases within the upper respiratory tract of the patient during the expiratory phase of the ventilatory support system of FIG. 1.
[0159] FIG. 4 illustrates a sagittal view of the intraoral mask of FIG. 5.
[0160] FIG. 5 illustrates a transverse cross-sectional view of a mouth guard of an intraoral mask according to an example of the present technology.
[0161] FIG. 6 illustrates a sagittal cross-sectional view of the mouth guard of FIG. 5, fitted to a patient.
[0162] FIG. 7 illustrates a perspective view of the mouth guard of FIG. 5, fully assembled.
[0163] FIG. 8 illustrates a plan view of the mouth guard of FIG. 5, disassembled.
[0164] FIG. 9 illustrates a schematic diagram of a ventilatory support system according to another example of the present technology, and the gas flows within the ventilatory support system during an inspiratory phase.
[0165] FIG. 10 illustrates a schematic diagram of a ventilatory support system according to yet another example of the present technology, and the gas flows within the ventilatory support system during an expiratory phase.
[0166] FIG. 11 illustrates a schematic diagram of a ventilatory support system according to yet another example of the present technology, and gas flows within the ventilatory system during an expiratory phase.
[0167] FIG. 12 illustrates the gas flows within the ventilatory support system of FIG. 11 during an inspiratory phase.
[0168] FIG. 13 illustrates the second flow of gases within the upper respiratory tract of the patient during the expiratory phase or inspiratory phase of the ventilatory support system of FIG. 11.
[0169] FIG. 14 illustrates a block diagram of an aeration system suitable for use in ventilatory support systems of the present technology.
[0170] FIG. 15 illustrates an example inlet module 1408 of the aeration system of FIG. 14. [0171] FIG. 16 illustrates an example control system for the aeration system of FIG.
14.
[0172] FIG. 17 illustrates an isometric view of an example aeration device suitable for use in ventilatory support systems of the present technology.
[0173] FIG. 18 illustrates a right side view of the aeration device of FIG. 17.
[0174] FIG. 19 illustrates a plan view of the aeration device of FIG. 17.
[0175] FIG. 20 illustrates a bottom view of the aeration device of FIG. 17.
[0176] FIG. 21 illustrates a reverse isometric view of the aeration device of FIG. 17.
DETAILED DESCRIPTION OF THE DRAWINGS
[0177] Invasive ventilation is life-saving medical intervention used to assist or replace spontaneous breathing in patients who are unable to breathe adequately on their own. But it has been found that potential side effects of invasive ventilation may include one or more of desiccation of the upper respiratory tract, accumulation of secretions, asynchrony, tracheitis, Ventilator-Associated Pneumonia (VAP), Ventilator-Associated Sinusitis (VAS), or disruption to the nasal cycle, for example.
[0178] Desiccation refers to the condition where the upper respiratory tract becomes abnormally dry. The desiccation may lead to mucosal damage, increased risk of infection, impaired mucociliary clearance, thickened secretions, or discomfort, for example.
[0179] Accumulation of secretions may promote bacterial overgrowth and colonization by pathogenic bacteria.
[0180] Asynchrony occurs when a spontaneously-breathing patient commences expiration while the mechanical ventilator is in an inspiratory phase, or commences inspiration while the mechanical ventilator is in an expiratory phase.
[0181] Tracheitis is an inflammation of the trachea without the radiological signs of pneumonia.
[0182] Ventilator-Associated Pneumonia (VAP) has, in addition to what occurs with tracheitis, radiological evidence of pneumonia. VAP is part of a spectrum of bacterial infections of the patient's respiratory system following invasive ventilation, e.g., for at least 48 hours. The most common cause of VAP is bacterial infection. [0183] Ventilator-Associated Sinusitis (VAS) is another infection associated with invasive ventilation. Infectious sinusitis is thought to affect about 27 % of mechanically ventilated patients. And the cause of undetermined fever in about 25 % of cases. The presence of VAS and VAP have been found to be associated.
[0184] The nasal cycle is a natural, physiological process in which an asymmetry of flow between the nasal passages varies over time. The predominant nasal airflow may alternate between the left and right nasal passages. This cycle typically occurs over a period of several hours and is a normal function of the nasal mucosa, the tissue lining the nasal cavities. Disruption to the nasal cycle may be a contributing factor to tracheitis, VAP, VAS, or other side effects of invasive ventilation.
[0185] It has been found that one or more of the above or other side effects of invasive ventilation may be ameliorated by aerating the upper respiratory tract during invasive ventilation.
[0186] During invasive ventilation, the upper respiratory tract is typically bypassed, e.g., by an endotracheal tube. As a result of introducing the endotracheal tube to the patient, the normal physiological functions occurring in the upper respiratory tract and the lower respiratory tract can be considered out of balance. For the lower respiratory tract, the addition of artificial heat and humidification may offer compensatory conditions that go some way toward restoring the conditions that the lower respiratory tract is accustomed to. Such that homeostasis is largely restored. The upper respiratory tract, however, receives no additional compensatory support (other than occasional oral care, suctioning, etc.). Hence the upper respiratory tract may remain largely out of balance. The nasopharynx, oropharynx, and laryngopharynx of the upper respiratory tract, for example, play a role in respiratory function. In this area there are chemoreceptors, neuroreceptors, hairs and turbinates to filter air, mechanisms for the humidification and warming of inspired air, cells that produce immunoglobulins, and secretions for inhibiting or preventing infection. Aerating the upper respiratory tract may restore, to at least some extent, the normal physiological behaviors in the upper respiratory tract during invasive ventilation. Aerating the upper respiratory tract with humidified gases, e.g., humidified towards or to a dew point of about 370 Celsius (C), may further enhance physiological benefits for the patient.
[0187] FIG. 1 and FIG. 2 illustrate, in schematic form, an example ventilatory support system 100 according to the present technology.
[0188] The ventilatory support system 100 supplies gases to a patient 102. The patient
102 is represented by the lower respiratory tract 104, e.g., the lungs, and the upper respiratory tract 106, e.g., the oral cavity and pharynx. Openings in the upper respiratory tract 106 represent the nares 108 and the mouth 110 of the patient.
[0189] A first patient interface of the ventilatory support system 100 may be an invasive patient interface. In this example, the invasive patient interface is an oral endotracheal tube 112. The oral endotracheal tube 112 passes through the upper respiratory tract 106 and into the lower respiratory tract 104. In other examples, the first patient interface may be a nasal endotracheal tube, a tracheostomy tube, or a laryngeal mask, for example.
[0190] The first patient interface, e.g., oral endotracheal tube 112, may include a cuff. The cuff 114 of the oral endotracheal tube 112 may be inflated to functionally separate, e.g., isolate, the lower respiratory tract 104 and the upper respiratory tract 106. In other examples, the first patient interface may not be configured to isolate the lower respiratory tract 104 from the upper respiratory tract 106. For example, an endotracheal tube for a neonatal patient may be uncuffed.
[0191] A distal end of the first patient interface, e.g., oral endotracheal tube 112, opens into the lower respiratory tract 104, e.g., the lungs, of the patient 102. Gases may be supplied to, or received from, the lower respiratory tract 104 of the patient 102 through the invasive patient interface, e.g., oral endotracheal tube 112.
[0192] A second patient interface of the ventilatory support system 100 may be a non- invasive patient interface. In this example, the non-invasive patient interface is an intraoral mask 116. In other examples, the second patient interface may be an invasive patient interface. The intraoral mask 116, is fitted to the patient 102. In other examples, as described in further detail below with reference to FIG. 11 and FIG. 12, the second patient interface may be an alternative interface such as a nasal cannula, or a nasal face mask, a nasal pillows interface, a nasal cannula, an intranasal tube, an oral face mask, an intraoral mask, or an intraoral tube.
[0193] The intraoral mask 116 opens into the upper respiratory tract 106, e.g., the oral cavity or pharynx. Gases may be supplied to, or received from, the upper respiratory tract 106, e.g., the oral cavity or pharynx, of the patient 102 through the second patient interface, e.g., intraoral mask 116. In some examples, the intraoral mask 116 may seal the patient's mouth as described in further detail below with reference to FIG. 5 to FIG. 8.
[0194] In the example ventilatory support system 100, a first gas source 118 is configured to supply a first flow of gases to the lower respiratory tract 104 of the patient 102. The first gas source 118 may be a mechanical ventilator, for example. In other examples or contexts, the first gas source may be referred to as a primary gas source or further gas source (i.e., further to the second gas source described below), for example. The first flow of gases may include any one, or a combination of any two or more, of air, oxygen, or heliox, for example. The first gas source may be configured to control the first flow of gases, e.g., a phase of the first flow of gases, based at least in part on one or more of a volume of the first flow of gases, a pressure of the first flow of gases, or spontaneous breathing of the patient.
[0195] The first gas source 118 may be pneumatically coupled with the first patient interface, e.g., by a first breathing circuit 120. The first breathing circuit 120 may include one or more of a first inspiratory limb 122, a first expiratory limb 124, or a first interface conduit 126. The first breathing circuit 120 in the illustrated example is a dual-limb breathing circuit. The first inspiratory limb 122 is configured to convey the first flow of gases from the first gas source 118, e.g., a gases outlet of the first gas source 118, to the first patient interface, e.g., oral endotracheal tube 112, via the first interface conduit 126. For example, during at least part of an inspiratory phase. The first expiratory limb 124 is configured to convey the first flow of gases from the oral endotracheal tube 112 to the first gas source 118, e.g., a gases return inlet of the first gas source 118, via the first interface conduit 126. For example, during at least part of an expiratory phase. In other examples, one or more of the first inspiratory limb 122 or the first expiratory limb 124 may be coupled directly with the first patient interface, e.g., oral endotracheal tube 112, optionally omitting the first interface conduit 126.
[0196] One or more of the first inspiratory limb 122, first expiratory limb 124, or first interface conduit 126 may be heated, e.g., include a heated conduit. Heating a conduit may advantageously inhibit or prevent the formation of condensate in the conduit or downstream components of the ventilatory support system 100, or dissipate condensate or other liquids within the conduit. In some examples, a heating wire may be provided within a lumen of the conduit, embedded in a wall of the conduit, or wrapped around the conduit. The first gas source 118 may be configured to control heating of the conduit, e.g., by controlling power supplied to the heating wire.
[0197] The first breathing circuit 120 may include a Y-piece (not shown). The Y-piece may couple, e.g., removably couple, together the first inspiratory limb 122, the first expiratory limb 124, and the first interface conduit 126 (or, in some cases, the first patient interface).
[0198] The first breathing circuit 120 may include a filter (not shown). The filter may be configured to inhibit or prevent the ingress of pathogens into the first gas source 118. The filter may be located between the first expiratory limb 124 and the gases return inlet of the first gas source 118, for example. [0199] The ventilatory support system 100 may include a first humidifier (not shown) configured to heat and humidify the first flow of gases. The first humidifier may include a heat source configured to heat a volume of water, or other humidifying liquid, contained within a humidifier chamber. The humidifier chamber may include chamber inlet configured to receive the first flow of gases from the first gas source 118, e.g., via a humidifier supply conduit, and a chamber outlet configured to supply the heated and humidified first flow of gases to the first patient interface. The humidifier chamber may be regarded as part of the first breathing circuit 120, e.g., the first inspiratory limb 122.
[0200] In some cases, the first patient interface, e.g., the oral endotracheal tube 112, may also be regarded as part of the first breathing circuit 120.
[0201] The first breathing circuit 120 may be supplied as a breathing circuit kit. The components of the first breathing circuit 120 may be packaged together, e.g., in sterile sealed packaging. Any two or more components of the first breathing circuit 120 may be pre-assembled. Pre-assembly may improve ease or efficiency in setting up the ventilatory support system 100. The first breathing circuit 120 may be disposable, e.g., to reduce the risk of cross-infection between different patients. In other examples, one or more components of the first breathing circuit 120 may be configured to be reprocessed for extended use by the same patient, or for use with two or more different patients. The reprocessing may include chemical disinfection or autoclaving, e.g., exposure to one or more of an elevated temperature or pressure for a predetermined period of time sufficient to sterilize the component. For example, a temperature of about 1200 Celsius (C) at a pressure of about 2 standard atmospheres (atm) for a period of between about 30 minutes (min) and 60 min. The components may be configured to withstand multiple reprocessing cycles, e.g., five or more, or ten or more, reprocessing cycles.
[0202] Together, the first gas source 118, first breathing circuit 120, and first patient interface may be regarded as forming a respiratory support system, or sub-system, of the ventilatory support system 100.
[0203] In the example ventilatory support system 100, a second gas source 128 is configured to supply a second flow of gases to the upper respiratory tract 106 of the patient 102. The second gas source may be a mechanical ventilator, for example. In other examples or contexts, the second gas source may be referred to as a secondary gas source, aeration device, nasal high flow device, second ventilatory support apparatus, or supplementary gas source, for example. The second flow of gases may include any one, or a combination of any two or more, of air, oxygen (O2), carbon dioxide (CO2), or heliox, for example. [0204] In some examples, as illustrated in FIG. 1, the first gas source 118 may be physically separate from the second gas source 128. In other examples, the first gas source 118 and the second gas source 128 may be enclosed within a single housing. In some examples, as shown in FIG. 1, the first gas source 118 may be pneumatically isolated from the second gas source 128. And the first flow of gases may be isolated from the second flow of gases. In other examples, as described in further detail below with reference to FIG. 9 or FIG. 10, the first gas source 118 may be pneumatically coupled with the second gas source 128.
[0205] The second gas source 128 may be configured to mimic, at least in part, one or more of the breathing cycle (e.g., timing of one or more of the inspiratory phase or the expiratory phase) or tidal volume of the first gas source 118.
[0206] The second gas source 128 may be pneumatically coupled with the second patient interface, e.g., by a second breathing circuit 130. The second breathing circuit 130 may include one or more of a second inspiratory limb 132, a second expiratory limb 134, or a second interface conduit 136. The second breathing circuit 130 in the illustrated example is a dual-limb breathing circuit. The second inspiratory limb 132 is configured to convey the second flow of gases from the second patient interface, e.g., the intraoral mask 116, to the second gas source 128, e.g., a gases return inlet of the second gas source 128, via the optional second interface conduit 136. For example, during at least part of an inspiratory phase. The second expiratory limb 134 is configured to convey the second flow of gases from the second gas source 128 to the second patient interface, e.g., intraoral mask 116, via the optional second interface conduit 136. For example, during at least part of an expiratory phase. In other examples, one or more of the second inspiratory limb 132 or the second expiratory limb 134 may be coupled directly with the second patient interface, e.g., intraoral mask 116, optionally omitting the second interface conduit 136.
[0207] One or more of the second inspiratory limb 132, second expiratory limb 134, or second interface conduit 136 may be heated, as described above with respect to the first breathing circuit 120.
[0208] The ventilatory support system 100 may include a second humidifier (not shown) configured to heat and humidify the second flow of gases. The humidifier chamber of the second humidifier may be regarded as part of the second breathing circuit 130, e.g., the second expiratory limb 134.
[0209] The second breathing circuit 130 may include one or more of a Y-piece, filter, humidifier chamber, or humidifier supply conduit as described above with respect to the first breathing circuit 120. [0210] In some cases, the second patient interface, e.g., the intraoral mask 116, may be regarded as part of the second breathing circuit 130.
[0211] The second breathing circuit 130 may be supplied as a breathing circuit kit as described above with respect to the first breathing circuit 120.
[0212] In some examples, the first breathing circuit 120 and the second breathing circuit 130 may be supplied together as a single breathing circuit kit. The first breathing circuit 120 and the second breathing circuit 130 may be packaged together, e.g., in sterile sealed packaging.
[0213] Together, the second gas source 128, second breathing circuit 130, and second patient interface may be regarded as forming an aeration system, or sub-system, of the ventilatory support system 100.
[0214] The arrows in FIG. 1 represent potential gas flows within the ventilatory support system 100 during at least part of an expiratory phase of the breathing cycle. The phase of the breathing cycle in this example may refer to the phase of the first gas source 118.
[0215] During at least part of the expiratory phase, the first gas source 118 receives the first flow of gases from the lower respiratory tract 104 of the patient 102. In this example, through the first patient interface, e.g., oral endotracheal tube 112, first interface conduit 126, and first expiratory limb 124. Meanwhile, the second gas source 128 supplies the second flow of gases to the upper respiratory tract 106 of the patient 102. In this example, through the second expiratory limb 134, second interface conduit 136, and second patient interface, e.g., intraoral mask 116. The second flow of gases may circulate within at least part of the upper respiratory tract 106 of the patient 102 before being vented from the upper respiratory tract 106 through the patient's nares 108.
[0216] The arrows in FIG. 2 represent potential gas flows within the ventilatory support system 100 during at least part of an inspiratory phase of the breathing cycle.
[0217] During at least part of the inspiratory phase, the first gas source 118 supplies the first flow of gases to the lower respiratory tract 104 of the patient 102. In this example, through the first inspiratory limb 122, first interface conduit 126, and first patient interface, e.g., oral endotracheal tube 112. Meanwhile, the second gas source 128 draws the second flow of gases from the upper respiratory tract 106 of the patient 102. In this example, through the second patient interface, e.g., intraoral mask 116, second interface conduit 136, and second inspiratory limb 132. The second flow of gases may be received into the upper respiratory tract 106 through the patient's nares 108, and may circulate within at least part of the upper respiratory tract 106 of the patient before being received from the upper respiratory tract 106 by the second gas source 128.
[0218] In other examples, as described below with reference to FIG. 9 and FIG. 10, the first gas source 118 and the second gas source 128 may be pneumatically coupled. Or, as described below with reference to FIG. 11 and FIG. 12, the second breathing circuit 130 may be a single-limb breathing circuit, and/or the second gas source 128 and the second patient interface may be configured to supply a uni-directional gas flow to the upper respiratory tract 106 during both the inspiratory phase and expiratory phase.
[0219] The second flow of gases supplied to the upper respiratory tract 106 of the patient 102 may include, or consist solely of, fresh gases. In other examples, as described below with reference to FIG. 10, the second flow of gases may include expiratory gases, e.g., the first flow of gases received from the lower respiratory tract 104 of the patient 102. The expiratory gases may be one or more of warmed, humidified, or supplemented with a further gas, e.g., carbon dioxide (CO2) between being received from the upper respiratory tract 106 and supplied to the upper respiratory tract 106.
[0220] In some examples, the breathing cycle may include one or more of an inspiratory pause or an expiratory pause. An inspiratory pause is a period during the inspiratory phase during which there is little or no flow of the first flow of gases. An expiratory pause is a period during the expiratory phase during which there is little or no flow of the first flow of gases.
[0221] It will be appreciated that, in the example ventilatory support system 100, the second flow of gases is not inspired into, or expired from, the patient's lungs. The terms "second inspiratory limb" and "second expiratory limb" are employed for clarity to distinguish between the respective limbs of the aeration system. In examples in which the second gas source 128 is synchronized with the first gas source 118, the second "inspiratory limb" 132 and second "expiratory limb" 134 may be regarded as referring to the limb of the aeration system which conveys the second flow of gases during the respective inspiratory or expiratory phase of the first gas source 118. FIG. 1, for example, illustrates gas flows during an expiratory phase of the first gas source 118, during which the first flow of gases is conveyed by the first expiratory limb 124 and the second flow of gases is correspondingly conveyed by the second expiratory limb 134.
[0222] The ventilatory support system 100 may advantageously aerate the upper respiratory tract 106 of the patient during ventilation of the lower respiratory tract 104. 1 Mitigating or avoiding the stagnancy associated with invasive ventilation bypassing the upper respiratory tract 106. The aeration may advantageously mimic, at least in part, the natural periodic gas flows in the upper respiratory tract 106 of a healthy human.
[0223] FIG. 3 illustrates the potential gas flows within the upper respiratory tract 106 of the patient during at least part of the expiratory phase of the ventilatory support system 100 as shown in FIG. 1.
[0224] For clarity, only the second flow of gases is illustrated in FIG. 3. But it will be appreciated that the first flow of gases may simultaneously flow through the oral endotracheal tube 112.
[0225] As described above, during at least part of the expiratory phase the second gas source supplies the second flow of gases to the upper respiratory tract 106 of the patient 102. The second flow of gases may exit the intraoral tube 314 into the oral cavity 304, and circulate within at least part of the upper respiratory tract 106 before being vented from the nares 108 of the patient. For example, as illustrated in FIG. 3, the second flow of gases may circulate within the oral cavity 304, oropharynx 308, upper part of the trachea 312 above the cuff 114 of the invasive patient interface, nasopharynx 306, and nasal cavity 302.
[0226] In some examples, the ventilatory support system 100 may be configured to control sealing of the invasive patient interface, e.g., oral endotracheal tube 112, within the trachea 312 of the patient 102. For example, by controlling inflation of the cuff 114. The ventilatory support system 100, e.g., first gas source 118 may be configured to selectively deflate or inflate the cuff 114, e.g., to allow for secretions to pass from the lower respiratory tract 104, e.g., the lungs, below the cuff to the upper respiratory tract 106, e.g., the oropharynx 308, above the cuff 114. The cuff 114 of the invasive patient interface, e.g., oral endotracheal tube 112, may be attached to a manometer. The degree of pressure in the cuff 114 may vary with the breathing cycle. For example, during at least part of the inspiratory phase the cuff 114 may be inflated. Inflation of the cuff 114 may isolate the lower respiratory tract 104 from the upper respiratory tract 106. During at least part of the expiratory phase, the cuff 114 may be partially or completely deflated. For example, to allow the passage of lung secretions to be expelled along the pressure gradient. A cough may be simulated by allowing an intrathoracic pressure build-up below the cuff 114 to be generated by the first gas source 118, followed by a sudden deflation of the cuff 114 simulating the opening of the glottis as occurs with a cough, allowing secretions to be expelled from the lungs. [0227] FIG. 4 to FIG. 8 illustrate an example intraoral mask 400 according to the present technology. The intraoral mask 400 may be used as the intraoral mask 116 in the ventilatory support system 100 of FIG. 1, for example.
[0228] FIG. 4 illustrates a sagittal cross-sectional view of the intraoral mask 400.
[0229] The intraoral mask 400 may include a mouth guard 402.
[0230] The mouth guard 402 is configured to be fitted at least partially within the mouth of the patient, e.g., between the teeth of the patient as described in further detail below with reference to FIG. 6. The mouth guard 402 may be configured to secure one or more tubes in position with respect to the patient. The mouth guard 402 may seal the mouth of the patient to inhibit or prevent the unintended passage of gases or liquids to or from the oral cavity of the patient.
[0231] As shown in FIG. 4, the mouth guard 402 may include an anterior rim 406 and a posterior rim 408. The anterior rim 406 may be longer than the posterior rim 408, in cross-section. For example, at least about twice as long. A channel 410 may be formed between the anterior rim 406 and the posterior rim 408. The anterior rim 406, posterior rim 408, and/or channel 410 may aid one or more of location, retention, or sealing of the mouth guard 402 within the mouth of the patient, as described in further detail below with reference to FIG. 6.
[0232] The intraoral mask 400 may include an intraoral tube 404.
[0233] The intraoral tube 404 is configured to convey a flow of gases, e.g., the second flow of gases of ventilatory support system 100. The intraoral tube 404 may include a number of holes 412 for passage of the flow of gases to or from the upper respiratory tract of the patient. The holes 412 may advantageously diffuse the flow of gases across a wider area of the upper respiratory tract 106 of the patient 102. The length, shape, diameter, and the number of holes 412 may vary from those shown in the drawing. In some examples, one or more of a distribution or dimensions of the holes 412 may be uniform. For example, a number of identical holes 412 may be uniformly distributed along a length, or a portion of the length, of the intraoral tube 404. In other examples, one or more of a distribution or dimensions of the holes 412 may vary, e.g., to better mimic natural respiratory gas flow of a healthy human.
[0234] A distal end of the intraoral tube 404 may be closed, as shown in FIG. 4. In other examples, the distal end of the intraoral tube 404 may be open as shown in FIG. 3. The open distal end may provide a single inlet/outlet for the flow of gases. A single outlet may advantageously direct the second flow of gases to the patient's pharynx or the upper part of the trachea 312, above the cuff 114 of the invasive patient interface. [0235] In some examples, when gases are received from the upper respiratory tract of the patient into the intraoral tube 404 during at least part of the expiratory phase, secretions may be sucked into the intraoral tube 404. The intraoral mask 400 may thereby aid in clearing secretions above the cuff of the invasive patient interface.
[0236] FIG. 5 illustrates a transverse cross-sectional view of the example intraoral mask 400, through the mouth guard 402.
[0237] In the mouth guard 402 are two apertures. A first aperture 502 may envelop an invasive patient interface, e.g., the oral endotracheal tube 112 of the ventilatory support system 100. A second aperture 504 may envelop the intraoral tube 404 as shown in FIG. 4.
[0238] The first aperture 502 and the second aperture 504 may have diameters that are sized to fit the oral endotracheal tube and the intraoral tube, respectively.
[0239] The first aperture 502 and the second aperture 504 may be arranged side-by- side, i.e., aligned horizontally as shown in FIG. 5. In other examples, the first aperture 502 and the second aperture 504 may be aligned vertically as shown in FIG. 3.
[0240] The intraoral tube may be separate or separable from the mouth guard 402. Or the intraoral tube may be permanently fixed in the mouth guard 402. The mouth guard may be manufactured in two or more different sizes to suit different patients. Alternatively, or additionally, the shape may be customized to fit individual patients. For example, the mouth guard 402 may be formed to suit a particular patient, e.g., by additive manufacturing. Or the mouth guard 402 may be moldable or malleable.
[0241] FIG. 6 illustrates the sagittal cross-sectional view of the intraoral mask 400 in position in a patient's mouth.
[0242] The mouth guard 402 may sit, at least in part, between the buccal surface of the lips and the gums and teeth. The anterior rim 406 of the mouth guard 402 is configured to sit in the oral vestibule of the patient, between the lips and one or more of the teeth or vestibular gingiva (gums). The posterior rim 408 is configured to sit anteriorly of the teeth. The teeth may be received within the channel 410 of the mouth guard 402. The anterior rim 406, posterior rim 408, and/or channel 410 may stabilize the intraoral mask 400 within in the mouth, e.g., against tube drag forces from the second interface conduit 136 of ventilatory support system 100. The mouth guard 402 may thus straddle and be stabilized by the teeth and gums of the patient.
[0243] The fit of the mouth guard 402 as described above may allow for the mouth to be sealed. Sealing the mouth may inhibit or prevent gases being expelled from the mouth when the ventilatory support system 100 is in the expiratory phase, and received through the mouth in the expiratory phase. Sealing the mouth may advantageously leave the nares and nasopharynx as the only apertures in the respiratory tract above the cuff, thus allowing a flow of warmed and humidified gases in the pharynx, inhibiting pooling of secretions, and inhibiting desiccation of the pharynx.
[0244] FIG. 7 illustrates a perspective view of the intraoral mask 400. The oral endotracheal tube and intraoral tube are omitted for clarity.
[0245] In some examples, the mouth guard 402 of the intraoral mask 400 may be assembled from two or more components. For example, an upper portion 702, a central portion 704, and a lower portion 706.
[0246] The upper portion 702 may include an anterior rim 406, posterior rim 408, and channel 410 configured to locate the mouth guard 402 with respect to the maxillary (upper jaw) of the patient.
[0247] The lower portion 706 may include an anterior rim 406, posterior rim 408, and channel 410 configured to locate the mouth guard 402 with respect to the mandible (lower jaw) of the patient.
[0248] The central portion 704 may include the first aperture 502 and the second aperture 504 configured to receive portions of the invasive patient interface, e.g., an oral endotracheal tube, and the intraoral tube, respectively. During assembly, one or more of the intraoral tube or endotracheal tube may be fed through the respective first aperture 502 or second aperture 504, either before or after the endotracheal tube is inserted.
[0249] The mouth guard 402 may be made from a soft material that has properties to minimize the formation of a biofilm, and may be easily cleaned or replaced daily. The mouth guard 402 may be premanufactured in various sizes or custom made or a combination. The mouth guard may be configured to be removed from the patient without dislodging the endotracheal tube, to allow oral and dental hygiene. For example, the upper portion 702 and lower portion 706 may be removed from the mouth of the patient, leaving the central portion 704 in place to mitigate or avoid interruption to the ventilation of the lower respiratory tract, and optionally aeration of the upper respiratory tract.
[0250] The mouth guard 402 may optionally include further apertures and/or tubes, other than the endotracheal tube and the intraoral tube 404. For example, a suctioning tube configured to extract secretions from the floor of the patient's mouth. [0251] FIG. 8 illustrates a plan view of the disassembled upper portion 702, central portion 704, and lower portion 706 of the mouth guard 402.
[0252] The upper portion 702 and lower portion 706 may include locating features 802. the locating features 802 may be configured to align and/or retain the upper portion 702 and the lower portion 706 upon assembly of the mouth guard 402. In some example, as shown in FIG. 8, the locating features 802 may include complementary elongate projections and slots. A slot on the lower portion 706 may be configured to be received, and optionally retained, by a complementary projection on the upper portion 702, or vice versa.
[0253] The central portion 704 may similarly include locating features (not shown) configured to align and/or retain the central portion 704 with one or more of the upper portion 702 or the lower portion 706 upon assembly of the mouth guard 402.
[0254] FIG. 9 illustrates, in schematic form, another example ventilatory support system 900 according to the present technology.
[0255] Aside from the differences described below or otherwise apparent from the drawings, the ventilatory support system 900 of FIG. 9 may be similar to the ventilatory support system 100 of FIG. 1 and FIG. 2. The description of elements and variants of ventilatory support system 100 are intended to apply equally to the ventilatory support system 900.
[0256] Unlike the ventilatory support system 100 of FIG. 1 and FIG. 2, in the ventilatory support system 900 the first gas source 118 and the second gas source 128 are pneumatically coupled. And the first flow of gases and the second flow of gases are not isolated. The ventilatory support system 900 may include a connection 902 pneumatically coupling a physically separate first gas source 118 and second gas source 128, as shown in FIG. 9. In other examples, the first gas source 118 and the second gas source 128 may be enclosed within a single housing, or replaced by a single gas source configured to supply gases to both the lower respiratory tract 104 and the upper respiratory tract 106. The first flow of gases and the second flow of gases may form, at least in part, a single sequential flow of gases as described in further detail below.
[0257] The arrows in FIG. 9 represent potential gas flows within the ventilatory support system 900 during at least part of an inspiratory phase of the breathing cycle. The phase of the breathing cycle in this example may refer to the phase of the first gas source 118.
[0258] During at least part of the inspiratory phase, the second gas source 128 draws the second flow of gases into the upper respiratory tract 106 of the patient 102 through the nares 108. Although not shown in FIG. 9, the second flow of gas may circulate within at least part of the upper respiratory tract 106 of the patient, e.g., the pharynx, before being received into the second gas source 128 through the non-invasive patient interface, e.g., intraoral mask 116, second interface conduit 136, and second inspiratory limb 132. The second flow of gases is then supplied to the first gas source 118 through the connection 902, and may form, at least in part, the first flow of gases supplied to the lower respiratory tract 104 of the patient 102. The first gas source 118, or the second gas source 128, may be configured to supplement, e.g., blend, the second flow of gases with one or more further gases, such as oxygen, to form the first flow of gases for supply to the lower respiratory tract 104 of the patient 102. The first flow of gases may be heated and/or humidified before it is supplied to the patient 102. The first gas source 118 supplies the first flow of gases to the lower respiratory tract 104 through the first inspiratory limb 122, first interface conduit 126, and invasive patient interface, e.g., oral endotracheal tube 112.
[0259] During at least part of the expiratory phase, not shown in FIG. 9, the first gas source 118 receives the first flow of gases from the lower respiratory tract 104 of the patient 102. In this example, through the oral endotracheal tube 112, first interface conduit 126, and first expiratory limb 124. Meanwhile, the second gas source 128 supplies the second flow of gases to the upper respiratory tract 106 of the patient 102. In this example, through the second expiratory limb 134, second interface conduit 136, and intraoral mask 116.
[0260] The ventilatory support system 900 may advantageously aerate the upper respiratory tract 106 of the patient during ventilation of the lower respiratory tract 104. Moreover, the ventilatory support system 900 may more closely mimic, at least in part, the natural physiology and breathing of a healthy human. For example, during at least part of the inspiratory phase the second flow of gases may be naturally warmed, humidified, and/or filtered by the patient's upper respiratory tract before forming, at least in part, the first flow of gases supplied to the lower respiratory tract 104 of the patient 102, including the lungs, for gas exchange. The nasal passages are lined with blood vessels. As gases flow through the nose, they come into close contact with these blood vessels, which transfer heat to the gases, warming it towards the patient's body temperature. The nasal mucosa (the moist lining of the nasal passages) contains mucous glands and serous glands that secrete mucus and other fluids. These secretions may add moisture to the gases, humidifying them before they reach the lungs, mitigating desiccation of the respiratory tract and maintaining efficient gas exchange in the lungs of the patient 102. The nasal passages may also act as a filter, trapping particles, dust, and/or pathogens. The vibrissae (nasal hairs) and the mucus layer may trap larger particles, while the cilia (hair-like structures) on the surface of the nasal mucosa may move the mucus and trapped particles. [0261] FIG. 10 illustrates, in schematic form, another example ventilatory support system 1000 according to the present technology.
[0262] Aside from the differences described below or otherwise apparent from the drawings, the ventilatory support system 1000 of FIG. 10 may be similar to the ventilatory support system 100 of FIG. 1 and particularly the ventilatory support system 900 of FIG. 9. The description of elements and variants of ventilatory support systems 100, 900 are intended to apply equally to the ventilatory support system 900.
[0263] Unlike the ventilatory support system 100 of FIG. 1 and FIG. 2, but like the ventilatory support system 900 of FIG. 9, the first gas source 118 and the second gas source 128 are pneumatically coupled, e.g., by connection 902. In other examples, the first gas source 118 and the second gas source 128 may be enclosed within a single housing, or replaced by a gas source including a single flow generator configured to supply gases to both the lower respiratory tract 104 and the upper respiratory tract 106.
[0264] The arrows in FIG. 10 represent potential gas flows within the ventilatory support system 1000 during at least part of an expiratory phase of the breathing cycle.
[0265] During at least part of the expiratory phase, the first gas source 118 receives the first flow of gases from the lower respiratory tract 104 of the patient 102, through the invasive patient interface, e.g., oral endotracheal tube 112, first interface conduit 126, and first expiratory limb 124. The first flow of gases is then supplied to the second gas source 128 through the connection 902, and may form, at least in part, the second flow of gases supplied to the upper respiratory tract 106 of the patient 102. The second gas source 128 (or the first gas source 118) may be configured to supplement, e.g., blend, the first flow of gases with one or more further gases, such as carbon dioxide (CO2), to form the second flow of gases for supply to the upper respiratory tract 106 of the patient 102. In this example, the second gas source 128 supplies the second flow of gases to the upper respiratory tract 106 of the patient 102. In this example, through the second expiratory limb 134, second interface conduit 136, and non-invasive patient interface, e.g., intraoral mask 116. Although not shown in FIG. 10, the second flow of gases may circulate within at least part of the upper respiratory tract 106, e.g., the pharynx, before being vented through the nares 108.
[0266] The ventilatory support system 1000 may advantageously aerate the upper respiratory tract 106 of the patient during ventilation of the lower respiratory tract 104. Moreover, the ventilatory support system 1000 may more closely mimic, at least in part, the natural physiology and breathing of a healthy human. For example, the composition of the second flow of gases may vary between the inspiratory phase and expiratory phase of the breathing cycle. There may be a higher proportion of CO2 in the second flow of gases in the expiratory phase due to the gas exchange between the first flow of gases and the lower respiratory tract 104 of the patient. The increase in CO2 in the upper respiratory tract 106 during at least part of the expiratory phase may have physiological benefits for the patient.
[0267] In another example, a ventilatory support system may be configured to both:
• supply the second flow of gases received from the upper respiratory tract 106 of the patient 102 to the lower respiratory tract 104 of the patient 102 during at least part of the inspiratory phase, as described above with reference to FIG. 9; and
• supply the first flow of gases received from the lower respiratory tract 104 of the patient 102 to the upper respiratory tract 106 of the patient 102 during at least part of the expiratory phase, as described above with reference to FIG. 10.
[0268] FIG. 11 and FIG. 12 illustrate, in schematic form, another example ventilatory support system 1100 according to the present technology.
[0269] Aside from the differences described below or otherwise apparent from the drawings, the ventilatory support system 1100 of FIG. 11 and FIG. 12 may be similar to the ventilatory support systems 100, 900, 1000 of FIG. 1, FIG. 9, and FIG. 10, respectively. The description of elements and variants of ventilatory support systems 100, 900, 1000 are intended to apply equally to the ventilatory support system 1100.
[0270] In the example ventilatory support system 1100, the non-invasive patient interface is a nasal cannula 1102. The nasal cannula 1102 includes a pair of nasal prongs each extending into a respective one of the patient's nares 108. The non- invasive patient interface, i.e., nasal cannula 1102, in this example is a non-sealing nasal cannula. The nasal prongs do not occlude the patient's nares 108. Gases may vent from the nares 108 about the nasal prongs. In other examples, the nasal cannula 1102 may be a sealing nasal cannula. The nasal prongs may seal within the nares 108. Or the non-invasive patient interface may be nasal face mask, nasal pillows interface, for example.
[0271] The second breathing circuit 130 in this example is a single-limb breathing circuit. The single-limb breathing circuit includes a delivery conduit 1104.
[0272] Like the ventilatory support system 100, but unlike ventilatory support systems 900, 1000, the first gas source 118 and the second gas source 128 of ventilatory support system 1100 may be pneumatically isolated. [0273] The second gas source 128 in this example may be configured to supply the second flow of gases as a uni-directional gas flow, as described in further detail below. For example, the second gas source 128 may include a centrifugal blower configured to generate a pressurized flow of gases from ambient air.
[0274] The second gas source 128 may be configured to control a flow rate of the second flow of gases. The second gas source 128 may be configured to maintain a constant flow rate of the second flow of gases throughout at least part, or an entirety, of one or more of the inspiratory phase, expiratory phase, or breathing cycle. In some examples, the second gas source 128 may be configured to maintain a constant flow rate throughout the entire breathing cycle. The second gas source 128 may be configured to provide nasal high flow. For example, the constant flow rate may be at least about 15 liters per minute (l/min), e.g., about 30 l/min.
[0275] In other examples, the second gas source 128 may be configured to vary the flow rate of the second flow of gases. The flow rate may be varied based, at least in part, on the phase of the breathing cycle. The flow rate may be synchronized with the breathing cycle. For example, the second gas source 128 may be configured to deliver the second flow of gases to the upper respiratory tract 106 of the patient 102 at a first flow rate during at least part, e.g., an entirety, of the inspiratory phase. And a second flow rate during at least part, e.g., an entirety, of the expiratory phase. The first flow rate and the second flow rate may be different to each other. The first flow rate may be higher than the second flow rate. For example, the first flow rate may be about 30 l/min, and the second flow rate may be about 15 l/min. Alternatively, the second flow rate may be higher than the first flow rate. The first flow rate and the second flow rate may each be non-zero flow rates. The first flow rate and the second flow rate may each be positive flow rates. The first flow rate and the second flow rate may each be at least about 15 liters per minute (l/min). Changes in the flow rate may be synchronized to coincide with an event in the breathing cycle, such as initiation of one or more of the inspiratory phase or the expiratory phase.
[0276] The second gas source 128 may be configured to determine a phase of the breathing cycle. The second gas source 128 may determine the breathing cycle by wired or wireless communication with the first gas source 118. Alternatively, or additionally, the second gas source 128 may be configured to determine the phase of the breathing cycle by sensing one or more properties of one or more of the first gas source 118, the first flow of gases, or the patient. For example, the second gas source 128 may include a sensor, e.g., one or more of a flow rate sensor or a pressure sensor, in the flow path of the first flow of gases. [0277] Further details of a device suitable for use as the second gas source 128 are described below with reference to FIG. 14 to FIG. 21.
[0278] The arrows in FIG. 11 represent potential gas flows within the ventilatory support system 1100 during at least part of an expiratory phase of the breathing cycle. The phase of the breathing cycle in this example may refer to the phase of the first gas source 118.
[0279] During at least part of the expiratory phase, the first gas source 118 receives the first flow of gases from the lower respiratory tract 104 of the patient 102. In this example, through the invasive patient interface, e.g., oral endotracheal tube 112, first interface conduit 126, and first expiratory limb 124. Meanwhile, the second gas source 128 supplies the second flow of gases to the upper respiratory tract 106 of the patient 102. In this example, through the delivery conduit 1104 and non-invasive patient interface, e.g., nasal cannula 1102. The second flow of gases may circulate within at least part of the upper respiratory tract 106 of the patient 102, e.g., one or more of the nasal cavity, pharynx, or oral cavity, before being vented from the upper respiratory tract 106 through the patient's mouth 110. Some of the second flow of gases may also be vented through the nares 108, around the nasal prongs of the nasal cannula 1102.
[0280] The arrows in FIG. 12 represent potential gas flows within the ventilatory support system 1100 during at least part of an inspiratory phase of the breathing cycle.
[0281] During at least part of the inspiratory phase, the first gas source 118 supplies the first flow of gases to the lower respiratory tract 104 of the patient 102. In this example, through the first inspiratory limb 122, first interface conduit 126, and invasive patient interface, e.g., oral endotracheal tube 112. Meanwhile, the second gas source 128 supplies the second flow of gases to the upper respiratory tract 106 of the patient 102. In this example, through the delivery conduit 1104 and non-invasive patient interface, e.g., nasal cannula 1102. The second flow of gases may circulate within at least part of the upper respiratory tract 106 of the patient 102, e.g., one or more of the nasal cavity, pharynx, or oral cavity, before being vented from the upper respiratory tract 106 through the patient's mouth 110. Some of the second flow of gases may also be vented through the nares 108, around the nasal prongs of the nasal cannula 1102.
[0282] The ventilatory support system 1100 may advantageously aerate the upper respiratory tract 106 of the patient during ventilation of the lower respiratory tract 104. And mitigate or avoid the stagnancy associated with invasive ventilation bypassing the upper respiratory tract 106. Moreover, pneumatic isolation of the first gas source 118 and second gas source 128 may advantageously permit greater flexibility in controlling the first flow of gases and the second flow of gases. For example, while the first flow of gases is bi-directional, the second flow of gases may be uni-directional, or the first flow of gases may be controlled based on a pressure or volume while the second flow of gases may be controlled based on a flow rate.
[0283] FIG. 13 illustrates the potential gas flows within the upper respiratory tract 106 of the patient 102 during either the expiratory phase or the inspiratory phase of the ventilatory support system 1100 as shown in FIG. 11 and FIG. 12, respectively.
[0284] For clarity, the first flow of gases is omitted from FIG. 13. But it will be appreciated that the first flow of gases may simultaneously flow through the oral endotracheal tube 112.
[0285] As described above, during one or more of the expiratory phase or the inspiratory phase, the second gas source supplies the second flow of gases to the upper respiratory tract 106 of the patient 102. The second flow of gases exits the nasal cannula 1102 into the nasal cavity 302, and circulates within at least part of the upper respiratory tract 106 before being vented from the mouth 110 of the patient 102. For example, as illustrated in FIG. 13, the second flow of gases may circulate within the nasal cavity 302, nasopharynx 306, oropharynx 308, laryngopharynx 310, the upper part of the trachea 312 above the cuff 114 of the invasive patient interface, e.g., oral endotracheal tube 112, and the oral cavity 304. Some of the second flow of gases may also be vented from the nares 108, e.g., around the nasal prongs 1302 of the nasal cannula 1102.
[0286] FIG. 14 illustrates, in schematic form, an example aeration system 1400 according to the present technology. The aeration system 1400, or sub-system, may be suitable for use in the ventilatory support system 1100, i.e., as the second gas source 128, delivery conduit 1104, and nasal cannula 1102.
[0287] The aeration system 1400 may include an aeration device 1402, delivery conduit 1428, and patient interface 1432. Other modules or elements may be present.
[0288] The device including the flow generator 1404 and humidifier 1406 will be referred to as an aeration device 1402, whereas the system including the flow generator 1404, humidifier 1406, delivery conduit 1428, and patient interface 1432 will be referred to as aeration system 1400. But these terms should not be considered limiting. The aeration system 1400 may omit the patient interface 1432 in some circumstances.
[0289] An example aeration device 1402 will be described with reference to FIG. 14 to FIG. 21. This is intended as a non-limiting example of an aeration device in accordance with the present technology. [0290] The aeration device 1402 is configured or operable to provide aeration to at least an upper respiratory tract of the patient via the delivery conduit 1428 and the patient interface 1432. The aeration device 1402 may be configured to be supported on a support stand.
[0291] The aeration device 1402 may be configured to provide nasal high flow (NHF). It will be appreciated that the components, methods, and processes described herein may be applied to other aeration devices and/or to other modes of operation delivered by such a device. For example, the aeration device 1402 may additionally or alternatively be configured or operable to provide pressure-based aeration such as continuous positive airway pressure (CPAP) and/or bi-level positive airway pressure (bilevel). When providing such aeration, the patient interface used may be a sealing patient interface.
[0292] The aeration device 1402 may be an integrated apparatus including a plurality of components in a single housing, or a discrete component-based arrangement where the components are separate but connected together.
[0293] With reference to FIG. 14, the aeration device 1402 may include a flow generator 1404 and a humidifier 1406. In some examples, as shown in FIG. 17 to FIG. 21, the flow generator 1404 and humidifier 1406 may be part of an integrated aeration device 1402, e.g., sharing a common housing 1702. In other examples, the aeration device 1402 could be a modular arrangement of discrete components, with the flow generator 1404 and humidifier 1406 being separate modules that can be connected together.
[0294] The aeration device 1402 may include an inlet module 1408 for providing gases such as air, oxygen (O2), carbon dioxide (CO2), one or more other supplemental gases, or a mix or two or more of the foregoing gases to the flow generator 1404. The inlet module 1408 may include one or more inlets for receiving flows of (or drawing in) ambient and/or pressurized air, oxygen, carbon dioxide, and/or other gases. For example, with reference to FIG. 15, in some examples the inlet module 1408 may include an ambient air inlet 1502, low-pressure gas inlet 1504, and/or high-pressure gas inlet 1506. A greater or lesser number of inlets may be provided in other examples. Some or all of the inlets may include connectors (such as ports, terminals, couplers, and the like) for establishing pneumatic connections to the sources of the gases. The inlet module 1408 may be considered to form part of the flow generator 1404, the aeration device 1402, or it may be a separate, modular component, depending on the context.
[0295] With reference to FIG. 15, a filter or multiple filters may be provided as part of the inlet module 1408, at or immediately downstream of the ambient air inlet 1502, the low-pressure gas inlet 1504, and/or the high-pressure gas inlet 1506. There may be a single filter 1516 positioned at the inlet or inlets to blower 1412 to filter particulates and pathogens carried with the incoming gases before they reach the blower 1412. Additionally, or alternatively, there may be individual filters positioned at each of the gas inlets 1502, 1504, 1506. In some examples, the filter 1508 may be provided between the high-pressure gas inlet 1506, at or upstream of the proportional valve 1510, in addition to a filter 1516 positioned at the inlet or inlets to the blower 1412, downstream of the proportional valve 1510 and the inlets 1502, 1504.
[0296] The aeration system 1400 may include a combination of components or modules selected from the following:
• a flow generator 1404, including an inlet module 1408, including one or more gas source inlets and their respective connectors (if applicable), a filter or filter module 1516, and a blower/sensor module 1410,
• non-return valve (NRV) 1418,
• a humidifier 1406 for humidifying the gases flow,
• a delivery conduit 1428, and/or
• a patient interface 1432.
[0297] The gas sources connected to the inlet module 1408 or inlets of the inlet module may include an in-wall ('piped') supply of supplementary gas (e.g., oxygen or carbon dioxide) or mixture of gases, a tank of supplementary gases, and/or a gas flow source such as an oxygen concentrator. The gas sources may provide the respective gas or gases at low or high pressures and/or low or high flow rates. In some examples, one or more of the gas sources may include a shut-off valve and/or regulator or other flow or pressure control mechanism which may be manually adjustable by a user. For example, one of the gas sources may be pressurized gas cylinder connected to the high- pressure gas inlet 1506 via a regulator and shut-off valve.
[0298] The flow generator 1404 may include a blower/sensor module 1410. The blower/sensor module 1410 may include a blower 1412 that controls flows delivered to the patient via the delivery conduit 1428 and patient interface 1432. The blower 1412 may be a centrifugal blower, including at least a motor and impeller or fan that is driven by the motor. Other types of blowers may be employed, such as axial blowers. The flow rate and/or pressure of flows of gases being output by the flow generator 1404 can be controlled by varying the output of the blower 1412, for example by varying the rotational speed of the motor driving the impeller or fan. The flow generator 1404 may be configured to provide flows of gases at high flow rates. Examples of high flow rates are described below.
[0299] The blower/sensor module 1410 may include a sensor module 1416. With reference to FIG. 14, in some examples the sensor module 1416 may be positioned downstream of the blower 1412 (i.e., an inlet of the sensor module 1416 may be pneumatically connected to the outlet of the blower 1412). In other examples, the sensor module 1416 may be positioned upstream of the blower 1412. The sensor module 1416 may be located upstream of the humidifier 1406.
[0300] One or more sensors (for example, Hall effect sensors) may be used to measure a motor speed of the blower motor.
[0301] Positioning sensors (e.g., flow rate, pressure, oxygen fraction, and/or other types of sensors in the sensor module 1416) downstream of the blower 1412 may increase accuracy of measurements, such as the measurement of fractional gas concentrations, including oxygen fraction, over systems that position the sensors upstream of the blower 1412 and/or a mixer. Positioning these sensors at a location further along the flow pathway, after the flow of gases has been more mixed (and may therefore be more homogeneous), may yield more consistent and/or repeatable measurements.
[0302] In some examples of the aeration device 1402, a non-return valve (NRV) 1418 may be located downstream of the blower 1412 or blower/sensor module 1410. And upstream of the flow generator outlet 1420 and/or the inlet to humidifier chamber 1422. The NRV 1418 may be positioned within the flow generator outlet 1420. The NRV 1418 inhibit or prevent backflow of gases, aerosols, and/or liquids into the flow generator 1404 via the humidifier 1406. During the provision of aeration, some flows of gases may travel up the delivery conduit 1428, back into the humidifier 1406 and potentially reaching the flow generator or displacing other gases that then travel into the humidifier and/or flow generator. These flows of gases may carry pathogens which could contaminate the flow generator. In addition, the flows of gases may transport water vapor (especially if returning via the humidifier 1406) which, over time, may damage the internal hardware of the flow generator if backflow is allowed to occur.
[0303] A humidifier 1406 may be provided between the flow generator 1404 and the device outlet 1424 and/or delivery conduit 1428 to humidify the flow of gases being output by the flow generator 1404. Humidification may be particularly useful where high flow rates of otherwise dry gases are delivered to the patient, as it may improve the toleration and comfort. Increasing the humidity of the gases to or closer to the natural levels in a healthy patient (e.g., 370 C dew point) may help to maintain the condition of the respiratory tract, mitigating or preventing drying-out or other effects which may cause discomfort and adverse health outcomes. In some examples the humidifier 1406 may be optional, in which case the aeration device 1402 may provide non-humidified gases from the flow generator 1404 to the patient.
[0304] The humidifier 1406 may be a heated humidifier, wherein the humidifier includes at least one heating element. The humidifier 1406 may be a heated pass-over humidifier. A heated pass-over humidifier typically includes a heater plate 1444, a heating element 1446 arranged and configured to heat the heater plate 1444, and a humidifier chamber 1422 including a heat-conductive base that is in close contact with the heater plate 1444 when in use. The humidifier chamber 1422 may be at least partially filled with water when in use. The heat-conductive base will transfer heat from the heater plate to the water, thereby causing controlled evaporation of the water to increase the humidity of a gases flow travelling through the chamber.
[0305] The patient interface 1432 may be a non-sealing patient interface such as a nasal cannula. The term 'non-sealing' as used when referring to patient interfaces may be defined as a patient interface having elements that do not completely seal a respiratory passage of the user from the outside environment. For example, a nasal prong of a non-sealing nasal cannula may ideally occlude 80% or less of a user's naris. Non-sealing patient interfaces may help to inhibit or prevent barotrauma (e.g., tissue damage to the respiratory tract and/or lungs due to differences in pressure relative to standard atmospheric pressure).
[0306] Various sensors configured to detect or measure properties or parameters of the aeration system 1400 and/or the flow of gases may be disposed at one or more locations throughout the aeration system 1400.
[0307] In some examples, the aeration system 1400 may include one or more, and optionally all, of:
• sensor 1514 at the ambient air inlet 1502 (e.g., a pressure, flow, temperature, and/or humidity (relative and/or absolute) sensor),
• sensor 1512 at or optionally downstream of the high-pressure gas inlet 1506 (e.g., a pressure and/or a flow sensor),
• sensor 1518 downstream of the proportional valve 1510 (e.g., a pressure and/or a flow sensor),
• sensor 1414 at the blower 1412, optionally proximal to the stator windings of the motor driving the blower (e.g., a temperature and/or a motor speed sensor), • sensor 1448 at the heating element 1446, or proximal to the heater plate 1444 (e.g., a temperature sensor),
• sensor 1426 downstream of the device outlet 1424 (e.g., a temperature sensor), or
• sensor 1430 at a patient end of the delivery conduit 1428 (e.g., a temperature sensor).
[0308] One or more of the sensors 1514, 1512, 1518, 1414, 1448, 1426, 1430 may each include multiple sensors. The multiple sensors may be part of a single package or separate, discrete sensors, or a combination of integrated sensor modules and discrete components.
[0309] Additional sensors may be provided as part of or within the sensor module 1416. The sensor module 1416 may be configured to measure properties of the gases flow travelling from the blower 1412 through to flow generator outlet 1420 and beyond. For example, the sensor module 1416 may include a sensor or sensors to detect the flow rate, oxygen concentration fraction (FdC ), pressure, temperature, and/or humidity of the flow of gases.
[0310] In addition to the sensors described above, various other sensors may be provided in and throughout the aeration system 1400. The sensors may be configured to detect, measure, and/or determine flow rate, pressure, temperature, humidity (e.g., relative and/or absolute humidity), oxygen concentration/fraction, and/or motor speed. Other sensors can be placed throughout the system and/or at, on or near the patient — for example, a pulse oximetry sensor 1450 may be attached to the patient and coupled to the controller 1436 via a pulse oximeter. Alternatively, or additionally, sensors from which the above parameters can be derived could be used.
[0311] Some or all of the sensors listed above may be electrically and/or communicatively connected to a controller 1436. The connection may be direct or indirect — e.g., via signal conditioning circuits, driver circuits, another controller, and/or other types of circuit. The connection(s) may be wired or wireless.
[0312] The controller 1436 may be a microprocessor, a microcontroller, a programmable logic device (such as a complex programmable logic device (CPLD) or field-programmable gate array (FPGA)), a digital signal processor (DSP), an applicationspecific integrated circuit (ASIC), or other suitable form of device, and may not necessarily be implemented in a single monolithic integrated circuit (IC) but may include additional discrete electrical and/or electronic components. The controller 1436 may include a single device or multiple devices and components. For example, the controller 1436 may include multiple microprocessors or microcontrollers.
[0313] The controller can include programming instructions for detection of input conditions and control of output conditions. The programming instructions can be stored in a memory of, or associated, with the controller 1436. The programming instructions may correspond to the methods, processes and functions described herein. The programming instructions can be executed by one or more processors of the controller 1436. The programming instructions can be implemented in C, C+ + , Java, or any other suitable programming languages or combinations thereof. Some or all of the portions of the programming instructions can be implemented in application specific circuitry such as ASICs and FPGAs.
[0314] In some examples, the outputs from at least some or all of the sensors described above are sent to the controller 1436 to assist the control of the aeration system 1400 and its constituent components or modules (e.g., the blower 1412, heating element 1446, delivery conduit 1428, display 8i I/O 1440, and other modules). The controller 1436 may be coupled to one or more of: the proportional valve 1510, blower 1412, humidifier heating element 1446, and/or a heated delivery conduit 1428. In some examples, the controller 1436 controls at least these and other parts of the aeration system 1400 as described herein. 'Control' as referred to herein may involve direct control of components (i.e., by signals output from the controller 1436) or indirect control via signal conditioning circuits or drivers/driving circuits (such as metal-oxide- semiconductor field-effect transistor (MOSFET) gate drivers or motor drivers), for example.
[0315] In some examples, the controller 1436 can operate the blower 1412 and/or the proportional valve 1510 to provide a flow of gas at a desired flow rate.
[0316] The controller 1436 may receive user input from a user interface of the display 8i I/O 1440. The user interface may include virtual and/or physical button(s) and/or dial(s). The user interface may include a touch-sensitive screen. The user input may include one or more of a target flow rate, pressure, oxygen fraction (i.e., FdO2 (fraction of delivered oxygen) or FiO2 (fraction of inspired oxygen)), mode (high flow, CPAP, etc.), alarm thresholds, and/or other parameters. The user can be a patient, healthcare professional, or others.
[0317] The controller 1436 may output information to a display 8i I/O 1440. The display 8i I/O 1440 may display warnings and/or other alerts. The display 8i I/O 1440 may be configured to display characteristics of sensed gases, or aeration parameters, for example, in real time or otherwise. The aeration parameters may include one or more of aeration time, flow rates, humidity levels, e.g., dew point, or pressures, for example.
[0318] FIG. 16 illustrates a block diagram of an example control system (which can be implemented on, by, or at least partially on or by the controller 1436 (and any other controllers or circuits described herein) that can detect patient and/or system conditions and control operation of the aeration system 1400, including any gases source(s). The control system 1600 can determine and generate the output control signals 1624-1632 based on one or more received inputs 1602-1622. The inputs 1602-1622 may correspond to sensor measurements and/or user inputs received by the controller 1436. The control system 1600 can receive one or more of pressure sensor inputs 1602, temperature sensor inputs 1604, flow rate sensor inputs 1606, motor speed sensor inputs 1608, gas fraction/concentration sensor inputs 1610, humidity sensor inputs 1612, pulse oximetry sensor inputs 1614 (for example, SpC and/or heart rate), stored or user parameter inputs 1616, duty cycle or pulse width modulation (PWM) duty inputs 1618, voltage inputs 1620, or current inputs 1622.
[0319] The aeration device 1402 may include one or more communications modules 1438. The communications modules 1438 may enable data communications with one or more external devices or servers over a data or communication link or data network, whether wired, wireless or a combination thereof. In some examples, the aeration device 1402 may include a wireless data transmitter, receiver, and/or transceiver to enable the controller 1436 to send and receive data signals in a wireless manner to/from external devices, including sensors (e.g., sensors affixed to a patient), patient monitoring systems, mobile phones or other devices, and/or remote servers. In one example, the one or more communications modules 1438 may include cellular (e.g., 3G, 4G, 5G, and/or 6G), Bluetooth™, and/or Wi-Fi™ modules. The one or more communications modules 1438 may include a singular module configured to perform communication using cellular, Bluetooth, and Wi-Fi technologies and protocols.
[0320] The one or more communications modules 1438 may deliver data to a remote patient management system (for example, implemented or located on a remote server) and/or enable remote control of the aeration device 1402 or aeration system 1400. The remote patient management system may include a single server, multiple servers, or multiple computing devices implemented in a cloud computing network. The communication may be two-way (bidirectional) communication between the aeration device 1402 and the remote patient management system, and/or another remote system.
[0321] The one or more communications modules 1438 may allow the controller 1436 to wirelessly send information to another local device such as, for example, a user or patient's mobile phone, tablet, smartwatch, etc. The aeration device 1402 may additionally, or alternatively, include a Near Field Communication (NFC) module to allow for local data transfer and/or data communication. In some examples, the aeration device 1402 may transmit data over a wired or wireless connection to the local user or patient device, for example via universal serial bus (USB), Wi-Fi™, Bluetooth™, or NFC, and the user or patient device may then wirelessly transmit data to a remote server, such as the remote patient management system (for example, via the Internet).
[0322] Estimated, measured, or determined parameters that are generated or received by the aeration device 1402 may be logged and/or transmitted via the one or more communications modules 1438 to a remote server. Usage information and selected aeration parameters may be transmitted. Aeration parameters — e.g., aeration time, flow rates, humidity levels, e.g., dew point, pressure, or other aeration parameters — may be transmitted, individually or together. In some examples, the aeration device 1402 or the user or patient device may generate an index that includes or is based on aeration parameters and is transmitted by the aeration device 1402 or the user or patient device to a remote server.
[0323] The remote patient management system may be implemented on a single server or a network of servers or a cloud computing system or other suitable architecture for operating a remote patient management system. The remote patient management system may include memory for storing received data and various software applications or services that can be executed to perform multiple functions. The remote patient management system may communicate information or instructions to the aeration device 1402 at least in part dependent on the data received. For example, the nature of the data received may trigger the remote server (or a software application running on the remote server) to communicate an alert, alarm, or notification to the aeration device 1402. The remote patient management system may store the received data for access by an authorized party such as a clinician, or the patient, or another authorized party. The remote patient management system may be configured to generate reports in response to a request from an authorized party. Aeration parameters may be included in the generated reports. The reports may include other data, e.g., respiratory rate, or device parameters such as flow rate(s), pressure(s), temperature(s), and/or humidity level(s).
[0324] With reference to FIG. 17 to FIG. 21, the aeration device 1402 may include a housing 1702. The housing 1702 may house the inlet module 1408, blower/sensor module 1410, and the heater plate 1444 and heating element 1446 of the humidifier 1406. The controller 1436, communications modules 1438, display 8i I/O 1440, and peripherals ports 1442 may also be positioned within or on the housing 1702. In other examples, the humidifier 1406 may be a separate module with its own housing and therefore not enclosed by the housing 1702 of the aeration device 1402.
[0325] The housing 1702 may include a housing upper chassis 1704 and a housing lower chassis 1706. The housing upper chassis 1704 may include a peripheral side wall 1802. The peripheral side wall 1802 may define a humidification chamber bay 1718 for receipt of the removable humidifier chamber 1422. The removable humidifier chamber 1422 may contain a suitable liquid for humidifying gases, such as water. A floor portion of the humidification chamber dock 1902 (hidden) can have a recess to receive a heater arrangement such as a heater plate 1444 or other suitable heating arrangements(s) for heating liquid in the humidifier chamber 1422 during a humidification process.
[0326] The aeration device 1402 may include an arrangement to enable the blower to deliver air, oxygen (or alternative auxiliary gases), or a suitable mixture thereof to the humidifier chamber 1422 and thereby to the patient. This arrangement can include an ambient air inlet in the peripheral side wall 1802 of the housing lower chassis 1706 of the housing 1702. Additionally, or alternatively, the ambient air inlet may be positioned in an underside/bottom wall 1806 of the housing 1702.
[0327] A filter cartridge can be positioned adjacent the ambient air inlet internally in the main housing and in communication with the blower 1412 to deliver filtered air and/or oxygen to the blower 1412 via an inlet port in the blower/sensor module 1410. The filter cartridge can include a filter 1516 configured to remove particulates (e.g., dust) and/or pathogens (e.g., viruses or bacteria) from the gases flow. The aeration device 1402 can include a separate oxygen inlet port positioned adjacent one side of the housing 1702 or at a rear end thereof, the oxygen port 1506 being for receipt of oxygen from an oxygen source such as a tank or source of piped oxygen. The oxygen inlet port 1506 may be in fluid communication with a proportional valve 1510. The proportional valve 1510 can suitably be a solenoid valve that enables electronic control of the amount of oxygen that is added to the gases flow that is delivered to the humidifier chamber 1422.
[0328] With reference to FIG. 17 to FIG. 19, a device outlet 1424 may include an L- shaped removable elbow 1728. The removable elbow 1728 may include a patient outlet port 1808 for coupling to the delivery conduit 1428 to deliver a flow of gases to a patient interface. The inlet to the removable elbow 1728 may extend at least substantially along the longitudinal axis 1722 while the outlet of the removable elbow 1728 (i.e., the patient outlet port 1808) may extend at least substantially along a vertical axis 1724. In other words, the patient outlet port 1808 may extend upwardly from the housing upper chassis 1704 of the aeration device 1402 main housing 1702. [0329] The patient outlet port 1808, gases inlet 1716 and gases outlet 1720 of the humidifier 1406 (or the inlet and outlet ports of the gases manifold 1714), device outlet 1424, and patient outlet port 1808 each or all can have soft seals such as O-ring seals or T-seals to provide a sealed gases passageway between the flow generator 1404, the humidifier chamber 1422, and the delivery conduit 1428.
[0330] The housing upper chassis 1704 may include an upper surface section 1710. With reference to FIG. 17 and FIG. 18, the upper surface section 1710 may protrude outwardly from the housing upper chassis 1704, such that it may extend at least partially over the flow generator outlet 1420 and the inlet to the removable elbow 1728.
[0331] The housing upper chassis 1704 may include the display 8i I/O 1440. The display 8i I/O 1440 can include a user interface which may include a display screen and input devices such as mechanical buttons or dials, a touch screen (e.g., a touch-sensitive liquid crystal display (LCD) or light emitting diode (LED) screen), a combination of a touch screen and mechanical buttons or dials, or the like. In one example, the user interface of the display 8i I/O 1440 may include a separate display and/or touch screen that is not permanently integrated with the housing 1702 but may be communicatively connected to the apparatus in a wired or wireless fashion. The aeration device 1402 may include a docking element for securing the separate display screen to the aeration device 1402, e.g., the housing 1702.
[0332] With reference to FIG. 17 to FIG. 19, the aeration device 1402 may include a display screen 1708 that may be part of the display 8i I/O 1440 (i.e., it may be the aforementioned display screen or touch-sensitive screen). The display screen 1708 can protrude from the housing 1702, for example, in an angled fashion. The angle of the display screen relative to a plane defined by the surface of the housing upper chassis 1704 may help to improve visibility and/or usability of the screen for users. For example, an angled display screen may be more easily viewed from a distance than a completely flat screen provided in the housing upper chassis 1704.
[0333] With reference to FIG. 14 and FIG. 17, a delivery conduit 1428 can be coupled to a device outlet 1424 formed in or as part of the housing 1702 of the aeration device 1402 at one end, and to a patient interface 1432, such as a non-sealing interface (for example, a non-sealing nasal cannula) at another end.
[0334] The gases flow generated by the flow generator 1404 may be humidified before being delivered to the patient via the delivery conduit 1428 and the patient interface 1432. The controller 1436 can control the flow generator 1404 to generate a flow of gases at a desired flow rate, and/or one or more valves (such as proportional valve 1510) to control the mixing of air and oxygen, carbon dioxide, and/or other supplemental gases by the blower 1412. The controller 1436 may control a heating element 1446 in or associated with the humidifier 1406, if present, to heat the gases flow to a desired temperature that achieves a desired level of temperature and/or humidity for delivery to the patient. The delivery conduit 1428 may be a heated conduit, including one or more conductors (i.e., heating elements) embedded within the walls of the supply conduit, which may be supplied with electrical current to heat the internal passageway(s) of the conduit. Alternatively, the heating element(s) may be attached to the interior surface of the delivery conduit 1428, or even float within the interior of conduit. The power supplied to the heating elements can be controlled by the controller 1436.
[0335] The humidifier 1406 of the apparatus may be configured to increase the humidity of the gases flow by introducing water vapor to gases passing through the humidifier chamber 1422. Various humidifier configurations may be employed. In one example, the humidifier 12 may include a removable humidifier chamber 1422 that is configured to contain one or more liquids. For example, the humidifier 1406 may be configured to allow the humidifier chamber 1422 to be partially or entirely removed or disconnected from the flow path and/or aeration device 1402. The humidifier chamber may be removed for refilling, cleaning, replacement and/or repair. With reference to at least FIG. 17 to FIG. 19, in one example, the humidifier chamber 1422 may be received and retained by or within the humidification chamber bay 1718 of the aeration device 1402, or may otherwise couple onto or within the housing 1702 of the aeration device 1402.
[0336] With continued reference to at least FIG. 17 to FIG. 19, the humidifier chamber 1422 of the humidifier 1406 may include at least a gases inlet 1716 and a gases outlet 1720 to enable connection to the gases flow path of the aeration device 1402, optionally via a gases manifold 1714 that connects between the flow generator outlet 1420 and humidifier gases inlet 1716, and the humidifier gases outlet 1720 and device outlet 1424. For example, the flow of gases from the device outlet 1424 of the flow generator 1404 is received into the humidifier chamber via its gases inlet and exits the humidifier chamber via its gases outlet 1720, after being heated and/or humidified.
[0337] The humidifier chamber 1422 may be configured to contain a volume of liquid, typically water. In operation, the liquid in the humidification chamber is controllably heated by one or more heaters (e.g., heater plate 1444) or heating elements (e.g., heating element 1446 of the heater plate 1444) associated with the humidifier 1406 to generate water vapor and thereby increase the humidity of the gases flowing through the humidifier chamber 1422. [0338] In some examples, the humidifier 1406 may be a heated pass-over humidifier.
In other examples, the humidifier may be a non-heated (i.e., cold) pass-over humidifier.
In yet other examples, the humidifier may be a non-pass-over humidifier.
[0339] The aeration device 1402 may be a nasal high flow (NHF) device.
GLOSSARY
[0340] "Aerate" and "aeration" refer to providing a flow of gases within the upper respiratory tract of the patient. The flow of gases may include any gas or gases mixture. For example, any one or more of air, oxygen, carbon dioxide, heliox, or water vapor. The flow of gases may circulate within at least part of the upper respiratory tract, e.g., one or more of the nasal cavity, oral cavity, nasopharynx, oropharynx, or laryngopharynx. Aeration may mitigate or avoid stagnancy within the upper respiratory tract, and one or more of the associated adverse health outcomes.
[0341] "Gas" or "gases," unless the context clearly requires otherwise, are each intended to encompass both a single gas, e.g., pure oxygen, or a gas mixture, e.g., air (i.e., nitrogen, oxygen, argon, carbon dioxide, and trace amounts of other gases).
[0342] "Homeostasis" refers to the maintenance of a metabolic equilibrium within a patient by compensating for the disruption from invasive ventilation, e.g., by aerating the upper respiratory tract of the patient.
[0343] "Invasive patient interface" refers to a patient interface which is inserted into a patient's respiratory tract, e.g., the trachea or pharynx, and bypasses the upper respiratory tract, e.g., at least the nasal cavity and the oral cavity. The invasive patient interface may be fitted to a patient by intubation or a surgical procedure such as a tracheotomy. The invasive patient interface may include a cuff. The cuff may be configured to isolate at least part of the lower respiratory tract from at least part of the upper respiratory tract. Examples of invasive patient interfaces include, without limitation, an oral endotracheal tube, a nasal endotracheal tube, a tracheostomy tube, or a laryngeal mask.
[0344] "Isolate," "seal," "functionally separate" and similar terms refer to inhibiting, or some cases preventing, the unintended passage of fluids, e.g., a gas or a liquid. They are not intended to imply that there is necessarily perfect isolation or perfect sealing, e.g., completely isolating the lower respiratory tract 104 from the upper respiratory tract 106. It is anticipated that there may be some unintended leakage. Moreover, in some contexts there may be an intentional "leak," as in the example of bias flow holes in a nasal face mask or full face mask for venting gases to ambient air. The term "sealing patient interface," for example, is not intended to exclude such patient interfaces.
[0345] "Lower respiratory tract" refers to the portion of the respiratory tract of an invasively ventilated patient below the cuff of the invasive patient interface. The lower respiratory tract may include a lower part of the trachea, bronchi, and lungs. If the invasive patient interface does not have a cuff, or is otherwise not configured to form a seal within the patient's respiratory tract, the "lower respiratory tract" refers to the portion of the respiratory tract that lies within the chest of the patient, including the trachea, bronchi, and lungs.
[0346] "Mechanical ventilator" refers to a medical device designed to provide ventilatory support to a patient by delivering a controlled flow of gases and pressure to a patient's respiratory tract via a patient interface. When the flow of gases is delivered to the lower respiratory tract of the patient, i.e., the lungs, the mechanical ventilator may provide respiratory support, assisting or replacing spontaneous breathing. When the flow of gases is delivered only to the upper respiratory tract, there may be other physiological benefits to the patient. The mechanical ventilator may be equipped with sensors, control systems, and safety mechanisms to regulate parameters such as tidal volume, respiratory rate, inspiratory and expiratory pressures, and oxygen concentration, ensuring precise and safe ventilation tailored to the patient's needs.
[0347] "Nasal high flow" (NHF) refers to a flow of humidified gases via an intentionally unsealed or non-sealing patient interface. Typical flow rates for adults often range from, but are not limited to, about 15 l/min to about 60 l/min or greater. Typical flow rates for pediatric users (such as neonates, infants, or children) often range from, but are not limited to, about 1 l/min per kilogram of user weight to about 3 l/min per kilogram of user weight or greater. For example, for an adult patient 'nasal high flow' may refer to the delivery of gases to a patient at a flow rate of greater than or equal to about 10 l/min, such as between about 10 l/min and about 100 l/min, or between about 15 l/min and about 95 l/min, or between about 20 l/min and about 90 l/min, or between about 25 l/min and about 85 l/min, or between about 30 l/min and about 80 l/min, or between about 35 l/min and about 75 l/min, or between about 40 l/min and about 70 l/min, or between about 45 l/min and about 65 l/min, or between about 50 l/min and about 60 l/min. For a neonatal, infant, or child patient 'nasal high flow' may refer to the delivery of gases to a patient at a flow rate of greater than 1 l/min, such as between about 1 l/min and about 25 l/min, or between about 2 l/min and about 25 l/min, or between about 2 l/min and about 5 l/min, or between about 5 l/min and about 25 l/min, or between about 5 l/min and about 10 l/min, or between about 10 l/min and about 25 l/min, or between about 10 l/min and about 20 l/min, or between about 10 l/min and 15 l/min, or between about 20 l/min and 25 l/min. A nasal high flow device with an adult patient, a neonatal, infant, or child patient, may deliver gases to the patient at a flow rate of between about 1 l/min and about 100 l/min, or at a flow rate in any of the sub-ranges outlined above. Nasal high flow can also optionally involve delivery of gas mixture compositions, e.g., including supplemental oxygen, carbon dioxide, or heliox, and/or administration of therapeutic medicaments.
[0348] "Non-invasive patient interface" refers to a patient interface which is external to the patient, or in some cases extends into the patient's nasal cavity or oral cavity, and supplies gases to the upper respiratory tract of the patient. The non-invasive patient interface may be fitted to a patient without the need for intubation or a surgical procedure such as a tracheotomy. Examples of non-invasive patient interfaces include, without limitation, a total face mask (sealing around the patient's eyes, nose, and mouth), a full face mask (sealing around the patient's nose and mouth), a nasal face mask (sealing around the patient's nose or nares), an oral face mask (sealing around the patient's mouth), an intraoral mask (extending and/or sealing within a patient's mouth), a nasal pillows interface, (sealing around and/or in each of the patient's nares), or a nasal cannula (extending into either or both of the patient's nares, in a sealing or non-sealing manner).
[0349] "Upper respiratory tract" refers to the portion of the respiratory tract of an invasively ventilated patient above the cuff of the invasive patient interface. The upper respiratory tract may include the nasal cavity, oral cavity, nasopharynx, oropharynx, and laryngopharynx. If the cuff is located within the trachea of the patient, the upper respiratory tract may also include an upper part of the trachea above the cuff. If the invasive patient interface does not have a cuff, or is otherwise not configured to form a seal within the patient's respiratory tract, the "upper respiratory tract" refers to the portion of the respiratory tract that is superior to the thorax of the patient, including the nasal cavity, oral cavity, pharynx, and larynx.
[0350] "Ventilate" or "ventilation," at least in the context of ventilating the lower respiratory tract of a patent, refers to the provision of a flow of gases to support respiration.
[0351] Anatomical terms such as "nasopharynx," "oropharynx," "laryngopharynx," "bronchi," and "nares" are referenced in accordance with the structures illustrated in Netter, F. H. (2022). Netter Atlas of Human Anatomy: A Systems Approach (8th ed., Enhanced Digital Version). Elsevier.
[0352] The terms "first," "second," and similar descriptors are employed for clarity to distinguish between comparable elements unless the context explicitly dictates otherwise. These terms do not imply a specific sequence or the necessity of another element. For instance, the term "second humidifier configured to heat and humidify the second flow of gases" does not inherently suggest the existence of a first humidifier, regardless of whether it is configured to heat the first flow of gases, the second flow of gases, or otherwise.
[0353] The expressions "one or more of," "at least one," and "and/or" are intended to denote any possible combination of the listed elements. For example, "one or more of X, Y, or Z," is meant to cover scenarios such as a single X alone, two instances of X alone, the combination of X and Y, the combination of Y and X, and so forth.
LISTING OF DRAWING ELEMENTS
100 ventilatory support system
102 patient
104 lower respiratory tract
106 upper respiratory tract
108 nares
110 mouth
112 oral endotracheal tube
114 cuff
116 intraoral mask
118 first gas source
120 first breathing circuit
122 first inspiratory limb
124 first expiratory limb
126 first interface conduit
128 second gas source
130 second breathing circuit
132 second inspiratory limb
134 second expiratory limb
136 second interface conduit
302 nasal cavity
304 oral cavity
306 nasopharynx
308 oropharynx
310 laryngopharynx
312 trachea
314 intraoral tube
400 intraoral mask
402 mouth guard
404 intraoral tube 406 anterior rim
408 posterior rim
410 channel
412 hole
502 first aperture
504 second aperture
702 upper portion
704 central portion
706 lower portion
802 locating feature
900 ventilatory support system
902 connection
1000 ventilatory support system
1100 ventilatory support system
1102 nasal cannula
1104 delivery conduit
1302 nasal prong
1400 aeration system
1402 aeration device
1404 flow generator
1406 humidifier
1408 inlet module
1410 blower/sensor module
1412 blower
1414 sensor
1416 sensor module
1418 NRV
1420 flow generator outlet
1422 humidifier chamber
1424 device outlet
1426 sensor
1428 delivery conduit
1430 sensor
1432 patient interface
1434 battery pack
1436 controller
1438 communications modules
1440 display 8i I/O
1442 peripherals ports
1444 heater plate 1446 heating element
1448 sensor
1450 pulse oximetry sensor
1502 ambient air inlet
1504 low-pressure gas inlet
1506 high-pressure gas inlet
1508 filter
1510 proportional valve
1512 sensor
1514 sensor
1516 filter
1518 sensor
1600 control system
1602 pressure sensor inputs
1604 temperature sensor inputs
1606 flow rate sensor inputs
1608 motor speed sensor inputs
1610 gas fraction/concentration sensor inputs
1612 humidity sensor inputs
1614 pulse oximetry sensor inputs
1616 user parameter inputs
1618 PWM duty inputs
1620 voltage inputs
1622 current inputs
1624 blower motor control outputs
1626 proportional valve control outputs
1628 heater plate control outputs
1630 heated breathing tube control outputs
1632 display & audio control outputs
1702 housing
1704 housing upper chassis
1706 housing lower chassis
1708 display screen
1710 upper surface section
1712 flow generator outlet
1714 gases manifold
1716 gases inlet
1718 humidification chamber bay
1720 gases outlet
1722 longitudinal axis 1724 vertical axis
1726 lateral axis
1728 removable elbow
1802 peripheral side wall
1804 feet
1806 underside/bottom wall
1808 patient outlet port
1902 floor portion of the humidification chamber dock