CN118076400A - Valve - Google Patents

Valve Download PDF

Info

Publication number
CN118076400A
CN118076400A CN202280063942.7A CN202280063942A CN118076400A CN 118076400 A CN118076400 A CN 118076400A CN 202280063942 A CN202280063942 A CN 202280063942A CN 118076400 A CN118076400 A CN 118076400A
Authority
CN
China
Prior art keywords
valve
actuator
pressure
gas
inlet
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202280063942.7A
Other languages
Chinese (zh)
Inventor
Z·J·弗林托夫
J·N·博思玛
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fisher and Paykel Healthcare Ltd
Original Assignee
Fisher and Paykel Healthcare Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fisher and Paykel Healthcare Ltd filed Critical Fisher and Paykel Healthcare Ltd
Priority claimed from PCT/IB2022/058897 external-priority patent/WO2023047286A1/en
Publication of CN118076400A publication Critical patent/CN118076400A/en
Pending legal-status Critical Current

Links

Landscapes

  • Safety Valves (AREA)

Abstract

A valve for a respiratory system arranged for delivering breathable gas to a patient, wherein the valve allows gas to be expelled from within the respiratory system, the valve comprising: a valve body comprising an inlet and an outlet, the inlet configured to be in fluid communication with the respiratory system; an actuator disposed within the valve body in a flow path between the inlet and the outlet, wherein the actuator is biased toward the inlet, and movement of the actuator away from the inlet is dependent at least in part on a gas pressure at the inlet, the movement adjusting the flow path between the inlet and the outlet to adjust the gas pressure in the respiratory system to within a predetermined range.

Description

Valve
Cross Reference to Related Applications
The present application claims priority from U.S. provisional patent application Ser. No. 63/261,439, filed on 21 at 9 at 2021, and U.S. provisional patent application Ser. No. 63/366,660, filed on 20 at 6 at 2022, the disclosures of which are incorporated herein by reference in their entireties.
Technical Field
The present disclosure relates to various devices, systems, and methods suitable for use in a respiratory system arranged for delivering breathable gas to a patient. In at least one aspect, the present disclosure relates to a valve for a respiratory system. In at least another aspect, the present disclosure is directed to a pressure regulating device for facilitating regulation of a pressure of a gas supplied to a patient.
Background
Positive End Expiratory Pressure (PEEP) and/or Peak Inspiratory Pressure (PIP) may be controllably provided to a patient through the respiratory system during breathing, resuscitation, or assisted breathing (ventilation).
PEEP is the pressure delivered to a patient during the expiratory phase of positive airway pressure, resuscitation, or assisted breathing. PIP is the desired highest pressure provided to a patient during the inspiratory phase of positive airway pressure, resuscitation, or assisted breathing. The patient may be a neonate or infant in need of respiratory assistance or resuscitation. Upon application of PEEP or PIP, the patient's upper airway and lungs are maintained open by the applied pressure and any fluid trapped in the patient's lungs is purged or reduced by the flow of air supplied to the patient.
Some existing respiratory systems are subject to flow variations, resulting in failure to achieve a target PEEP pressure. These flow changes may be caused by accidental leakage or automatic PEEP (also referred to as unintentional PEEP), and these factors are not considered during system calibration. Unexpected leaks may occur due to improper seals on the patient interface, incorrect patient interface size and assembly, patient coughing, movement, etc. Unexpected leaks may adversely reduce the pressure of the breathable gas delivered to the patient during respiratory therapy.
Automated PEEP is a phenomenon that occurs when a patient is actively ventilated, with pressure alternating between PIP and PEEP, and the patient is still exhaling from the last inflation at the beginning of the next inflation. This may occur when the expiration time (i.e., the time between puffs) is short, the expiration volume is large, or there is resistance to the flow of expiration gas. A potential impact of automatic PEEP is that the pressure received by the patient during respiratory therapy is higher than the target PEEP at the end of the expiratory phase.
Any reference or discussion of any document, act or knowledge in this specification is included solely for the purpose of providing a context for the present invention. It is not suggested or represented that any of these matters or any combination thereof formed part of the common general knowledge at the priority date or were known to be relevant to an attempt to solve any problem with which this specification is concerned.
Disclosure of Invention
In a first aspect, the present disclosure provides a valve for a respiratory system arranged to deliver breathable gas to a patient, wherein the valve allows gas to be expelled from within the respiratory system, the valve comprising:
A valve body comprising an inlet and an outlet, the inlet configured to be in fluid communication with the respiratory system;
an actuator disposed within the valve body in a flow path between the inlet and the outlet,
Wherein the actuator is movable by the gas, the movement of the actuator being at least partially dependent on the gas pressure at the inlet, wherein the movement adjusts the flow path between the inlet and the outlet to regulate the gas pressure in the respiratory system within a predetermined range.
In some embodiments, the actuator is biased toward the inlet of the valve.
In a second aspect, the present disclosure provides a valve for a respiratory system arranged to deliver breathable gas to a patient, wherein the valve allows gas to be expelled from within the respiratory system, the valve comprising:
A valve body comprising an inlet and an outlet, the inlet configured to be in fluid communication with the respiratory system;
an actuator disposed within the valve body in a flow path between the inlet and the outlet,
Wherein the actuator is biased towards the inlet and movement of the actuator away from the inlet is at least partially dependent on the gas pressure at the inlet, said movement adjusting the flow path between the inlet and the outlet to adjust the gas pressure in the respiratory system within a predetermined range.
In some embodiments, the actuator moves away from the inlet when the pressure exceeds a selected pressure level.
In some embodiments, the predetermined range is a predetermined PEEP pressure range.
In some embodiments, the selected pressure level is within the predetermined PEEP pressure range.
In a third aspect, the present disclosure provides a valve for a respiratory system arranged to deliver breathable gas to a patient, wherein the valve allows gas to be expelled from within the respiratory system, the valve comprising:
A valve body comprising an inlet and an outlet, the inlet configured to be in fluid communication with the respiratory system;
an actuator disposed within the valve body in a flow path between the inlet and the outlet,
Wherein the actuator is biased toward the inlet, the actuator moving away from the inlet when the pressure exceeds a selected pressure level, the movement adjusting a flow path between the inlet and the outlet to regulate the pressure of gas in the respiratory system within a predetermined PEEP pressure range, wherein the selected pressure level is within the predetermined PEEP pressure range.
In some embodiments, the valve includes a biasing member operatively coupled to the actuator.
In some embodiments, the actuator is biased toward the inlet by the biasing member.
In some embodiments, the biasing member applies a variable resistance to the actuator during movement of the actuator.
In some embodiments, the variable resistance applied by the biasing member counteracts the force applied to the actuator caused by the gas pressure at the inlet.
In some embodiments, the flow path between the inlet and the outlet of the valve is closed when the pressure at the inlet is below a selected pressure level.
In some embodiments, when the pressure at the inlet is above a selected pressure level, the pressure overcomes the variable resistance applied to the actuator by the biasing member and opens a flow path between the inlet and the outlet of the valve.
In some embodiments, the biasing member biases the actuator against a portion of the valve body when the flow path is closed.
In some embodiments, the portion of the valve body forms a valve seat of the actuator.
In some embodiments, when the actuator is displaced from the valve seat, a flow path between the inlet and outlet of the valve is opened.
In some embodiments, the flow path is determined at least in part by the relative displacement of the actuator from the valve seat.
In some embodiments, the flow path increases in size as the actuator is displaced farther away from the valve seat.
In some embodiments, the flow path decreases in size as the actuator moves closer to the valve seat.
In some embodiments, the valve includes a support member for the actuator for guiding and stabilizing movement of the actuator.
In some embodiments, the support member is an elongate shaft along which the actuator is arranged to slide during movement thereof.
In some embodiments, the actuator includes an aperture for receiving the shaft therein.
In some embodiments, the cross-section of the shaft, and the aperture are configured to have substantially similar shapes and/or sizes.
In some embodiments, the orifice has a diameter of approximately 1 to 5 mm.
In some embodiments, the aperture is formed at or near the center of the actuator.
In some embodiments, the actuator includes a substantially planar lower surface.
In some embodiments, the actuator comprises a circular disc, wherein the circular disc comprises a substantially flat lower surface.
In some embodiments, the size or area of the circular disk closely matches the size of the valve inlet.
In some embodiments, the actuator includes a portion for engaging the biasing member.
In some embodiments, the portion includes a raised portion extending above an upper surface of the actuator.
In some embodiments, the raised portion extends at least partially into the interior space of the biasing member.
In some embodiments, the valve body defines a chamber, wherein the inlet is formed at or near one end of the chamber and the outlet is formed at or near the other end of the chamber.
In some embodiments, the valve body includes a housing and an outlet member.
In some embodiments, the outlet member is arranged to be coupled to an end of the housing.
In some embodiments, the outlet member is removably coupled to an end of the housing.
In some embodiments, the outlet member includes threaded portions configured to couple to complementary threaded portions formed in the housing.
In some embodiments, the housing comprises a hollow cylindrical shape, and the valve seat is formed on an inner wall of the housing.
In some embodiments, the outlet member is integrally formed with or permanently connected to the housing.
In some embodiments, the outlet member includes at least one outlet member orifice to vent gas received at the inlet of the valve to ambient air.
In some embodiments, the outlet member aperture has a minimum area of approximately 20mm 2.
In some embodiments, the outlet member orifice forms an outlet of the valve.
In some embodiments, the outlet of the valve is arranged to be blocked when the PIP is delivered to the patient.
In some embodiments, the outlet of the valve is arranged to be blocked by the finger or digit of the operator during PIP delivery.
In some embodiments, the outlet of the valve is not blocked when PEEP is delivered to the patient.
In some embodiments, the shaft is received by an aperture of the actuator at a first end and connected to a portion of the valve body at a second end.
In some embodiments, the outlet member includes one or more arms disposed at or near the outlet member aperture, wherein the second end of the shaft is connected to the one or more arms.
In some embodiments, the outlet member includes a plurality of arms extending radially outward from a center of the outlet member.
In some embodiments, the biasing member is a spring.
In some embodiments, the biasing member is a coil spring.
In some embodiments, the biasing member is a conical coil spring.
In some embodiments, the biasing member is maintained in a compressed state when the actuator is biased toward the valve seat.
In some embodiments, the biasing member is further compressed when the actuator is lifted off the valve seat.
In some embodiments, the variable resistance applied to the actuator by the biasing member depends at least in part on: the spring constant of the spring, the spring compression, and/or the displacement of the actuator from the valve seat.
In some embodiments, the variable resistance applied by the biasing member to the actuator may be calculated as F Bias of =k (x_initial compression+x_lift), where:
K=the spring constant of the spring;
X_initial compression = initial compressed length of the spring when the flow path is closed (i.e., the difference between the original uncompressed length of the spring and the length of the spring after initial compression and placement within the valve body);
X_lift = displacement of the actuator from the valve seat under pressure P.
In some embodiments, the gas pressure at the inlet applies a lifting force (F Lifting up ) to the actuator in a direction opposite to the variable resistance applied to the actuator by the biasing member.
In some embodiments, the lifting force may be calculated according to F Lifting up ＝P*A actuator with a spring , wherein:
P=gas pressure at the valve inlet;
A actuator with a spring =the area of the actuator exposed to the gas pressure at the valve inlet.
In some embodiments, the movement of the actuator is determined by the relative relationship of F Bias of and F Lifting up .
In some embodiments, the actuator is displaced from the valve seat when F Lifting up is greater than F Bias of .
In some embodiments, the actuator begins to move closer to the valve seat when F Lifting up is less than F Bias of .
In some embodiments, the spring constant is determined at least in part by one or more of: spring wire diameter, free length of the spring, diameter of the spring coils, number of spring coils, solid height of the spring, spring pitch, etc.
In some embodiments, the spring constant is less than 0.05N/mm.
In some embodiments, the spring constant is between 0.005 and 0.02N/mm.
In some embodiments, the biasing member is configured to remain in a compressed state between the actuator and the outlet member when the actuator engages the valve seat.
In some embodiments, the outlet member is configured to adjust the compression of the spring by adjusting the distance of the outlet member relative to the actuator.
In some embodiments, the compression of the spring is adjusted by moving the outlet member closer to or farther from the actuator.
In some embodiments, the compression of the spring is adjusted by twisting the outlet member in a first or second direction, wherein when the outlet member is twisted in the first direction, the outlet member moves closer to the actuator and further compresses the spring, and when the outlet member is twisted in the second direction, the outlet member moves farther from the actuator and reduces the compression of the spring.
In some embodiments, twisting of the outlet member adjusts a predetermined pressure range that the valve is configured to regulate.
In some embodiments, the pressure at the valve inlet is determined at least in part by the pressure of the gas within the respiratory system.
In some embodiments, the pressure at the valve inlet is substantially the same as the pressure of the gas within the respiratory system.
In some embodiments, the pressure of the gas within the respiratory system is determined at least in part by an unexpected leak resulting in the pressure being below or above the target PEEP pressure to be delivered to the patient and/or a change in flow through the valve caused by patient breathing.
In some embodiments, the valve is arranged to compensate for unintended leakage by reducing the size of the gas flow path through the valve.
In some embodiments, the valve is arranged to compensate for the patient's breathing by allowing a variable portion of the gas within the respiratory system to flow through the valve and out of the respiratory system.
In some embodiments, the respiratory system is configured to deliver a flow rate in the range of 1L/min to 150L/min or 20L/min to 70L/min, or up to about 50L/min, or up to about 30L/min to an adult patient and a flow rate in the range of 5-15L/min to a neonatal patient when delivering respiratory therapy.
In some embodiments, the predetermined PEEP pressure range is between 5 and 15cm H 2 O.
In some embodiments, movement of the actuator can regulate the pressure of the breathable gas within the respiratory system, which can range from-2 to +2cm H 2 O.
In some embodiments, movement of the actuator can regulate the pressure of the breathable gas within the respiratory system, which can range from-1 to +1cmh 2 O.
In some embodiments, movement of the actuator is capable of adjusting the pressure of the breathable gas within the respiratory system, ranging from-0.5 to +0.5cm H 2 O.
In some embodiments, the selected pressure level is in the range of 4.5 to 5.5cm H 2 O.
In some embodiments, the selected pressure level is in the range of 4 to 6cm H 2 O.
In some embodiments, the selected pressure level is in the range of 3 to 7cm H 2 O.
In some embodiments, the selected pressure level is in the range of 6 to 10cm H 2 O.
In some embodiments, the valve is configured to be removably attached to a ventilation orifice of the respiratory system.
In some embodiments, the vent aperture is provided in a tee device.
In some embodiments, the ventilation aperture is disposed in an exhalation tube of the CPAP device.
In some embodiments, the valve includes an adapter to allow the valve to be detachably coupled to the respiratory system.
In some embodiments, the valve is configured to be detachably coupled to the tee device.
In some embodiments, the valve is configured to be detachably coupled to an exhalation tube of the CPAP device.
In a fourth aspect, the present disclosure provides an apparatus for a respiratory system arranged to deliver breathable gas to a patient, the apparatus comprising:
a housing including an inlet configured to be in fluid communication with the respiratory system to receive a flow of gas therefrom, an outlet configured to be in fluid communication with the patient interface, and a vent;
The valve according to the first, second or third aspect of the present disclosure, wherein the valve is configured to be removably attached to or integrally formed with a vent of the housing.
In some embodiments, the device is a tee resuscitator device.
In some embodiments, the device further comprises an opening (which may comprise an optional valve, such as a duckbill valve) for insertion of an auxiliary device, such as a cannula for fluid removal or delivery of surfactant to the patient.
In some embodiments, the device includes an adapter to allow the valve to be detachably coupled to the respiratory system.
In some embodiments, the device is arranged to be detachably coupled to an exhalation tube of a CPAP device.
In a fifth aspect, the present disclosure provides a kit of parts for a respiratory system, the kit of parts comprising:
A valve according to the first, second or third aspect of the present disclosure; and
A tee device, wherein the valve is connectable to a vent of the tee device.
In some embodiments, the kit of parts includes a patient interface connectable to an outlet of the tee device.
In some embodiments, the patient interface includes a range of different sizes and/or adaptations.
In some embodiments, the kit of parts includes a flexible hose connectable to the inlet of the tee device.
In some embodiments, the kit of parts includes one or more conduits connectable to a respiratory device to receive a flow of breathable gas therefrom.
In some embodiments, the kit of parts comprises a connector for establishing a connection between the valve and the tee device, and/or between the one or more conduits and the breathing apparatus, and/or between the tee device and the flexible hose.
In some embodiments, the patient interface may be a CPAP interface.
In a sixth aspect, the present disclosure provides a respiratory system for delivering respiratory therapy to a patient, the respiratory system comprising:
A breathing apparatus that supplies a source of breathable gas at a target pressure and/or flow rate;
A conduit assembly connectable to the respiratory apparatus to receive the flow of breathable gas;
A patient interface arranged to receive breathable gas and operable to deliver respiratory therapy to a patient;
Means arranged for forming a fluid connection between the catheter assembly and the patient interface; and
The valve according to the first, second or third aspect of the present disclosure.
In some embodiments, the respiratory system may be connected to a gas source, which may be a wall-mounted gas source.
In some embodiments, the respiratory system may further comprise a humidifier for humidifying the breathable gas before it is delivered to the patient.
In some embodiments, the device comprises a housing comprising:
an inlet arranged to receive breathable gas from the breathing apparatus;
an outlet configured to be in fluid communication with an inlet of the patient interface;
A vent arranged to allow gases within the respiratory system to escape from the respirator to ambient air.
In some embodiments, the valve may be connected to a vent of the device.
In a seventh aspect, the present disclosure provides an apparatus for facilitating regulation of pressure of a gas supplied to a patient, the apparatus comprising:
A housing defining a chamber, the housing having an inlet configured to connect with a source of a gas flow providing a flow of gas to the chamber, an outlet configured to direct gas from the chamber, and a vent comprising an actuator for controlling the discharge of gas from the chamber through the vent;
a biasing member biasing the actuator toward the seating position;
Wherein the vent and the actuator are mutually adapted such that the actuator has an exposed area exposed to the gas in the chamber, wherein the biasing member comprises a spring constant selected relative to the exposed area of the actuator, wherein the actuator is maintained in the seating position until the pressure of the gas in the chamber exceeds a selected pressure level.
In some embodiments, the spring constant may be in the range of 0.005N/mm to 0.02N/mm.
In some embodiments, the exposed area of the actuator may be between 70mm 2 and 320mm 2, or in the range of 100mm 2 to 250mm 2, or in the range of 120mm 2 to 200mm 2, or in the range of 140mm 2 to 180mm 2.
In some embodiments, the exposed area may be, for example, about 160mm 2.
In some embodiments, the device may be configured to supply a flow of gas between 5L/min and 15L/min to the patient.
In some embodiments, the device may be configured to supply a flow of gas to the patient of about 12L/min.
In some embodiments, when the patient is an adult, the pressure regulating device may be configured to accommodate a flow rate in the range of 1L/min to about 150L/min or about 20L/min to 70L/min, or up to about 50L/min, or up to about 30L/min.
In some embodiments, the selected pressure level may be Positive End Expiratory Pressure (PEEP) in the range of between 5 and 15cm H 2 O, or in the range of 6 to 10cm H 2 O, or in the range of 4cm H 2 O to 8cm H 2 O, or in the range of 3cm H 2 O to 7cm H 2 O.
In some embodiments, the selected pressure may be a Peak Inspiratory Pressure (PIP) in the range of between 20cm H 2 O and 80cm H 2 O, or in the range of between 20cm H 2 O and 40cm H 2 O.
In some embodiments, the vent and actuator are adapted to each other such that the actuator moves along the vent axis when moving relative to the seating position.
In one embodiment, the pressure regulating device includes an outlet member associated with the vent, the outlet member including a support member aligned with the vent axis, the actuator having an aperture formed therein, the aperture receiving the support member such that the actuator moves along the support member when moved relative to the seating position.
In some embodiments, the support member may include a shaft configured to extend through the aperture, the aperture extending through the actuator such that the actuator moves relative to the shaft.
In some embodiments, the aperture may be a blind hole.
In some embodiments, the mutual dimensions of the shaft and the orifice are designed to be within a tolerance range of 0.15mm to 0.025mm such that any gas flow through the gap formed between the shaft and the orifice is negligible.
In some embodiments, the vent may be configured to position an outlet member downstream of the actuator, the outlet member having an orifice through which gas passes when venting, the orifice being configured relative to the actuator such that the outlet member provides less restriction to the flow of gas exiting through the vent outlet than when the actuator is moved away from the seating position.
In some embodiments, the aperture is configured to be selectively occluded, such as by placing a user's finger thereon.
In some embodiments, the actuator and the outlet member may be configured to position a biasing member therebetween.
In some embodiments, the biasing member may be adapted to extend coaxially with the vent axis.
In some embodiments, the outlet member is adapted to engage the first end of the biasing member to inhibit movement of the biasing member in a direction that is not aligned with the vent axis.
In some embodiments, the actuator is adapted to engage the second end of the biasing member to also inhibit movement of the biasing member in a direction that is not aligned with the vent axis.
In some embodiments, the actuator may be annular in shape.
In some embodiments, the actuator and vent are mutually adapted so that the gas exiting the chamber exits uniformly over the perimeter of the actuator so that the pressure remains uniformly distributed over the exposed surface as the actuator moves from the seating position.
In some embodiments, the vent and the outlet member are adapted to engage one another.
In one arrangement, the vent includes a threaded inner surface and the outlet member includes a threaded outer surface such that the threaded engagement allows the outlet member to be positioned in the vent, thereby impeding manual adjustment of the outlet member relative to the vent outlet when the device is in use.
In another arrangement, the vent includes an outlet member configured to interact with the biasing member to adjust the compression percentage of the biasing member when the actuator is in the seating position.
In some embodiments, the vent is integrally formed with the outlet member, the vent includes a threaded outer surface, and the outlet member includes a threaded inner surface such that the threaded engagement allows manual adjustment of the outlet member relative to the vent when the device is in use.
In some embodiments, the engagement between the vent and the outlet member may be achieved by welding, clamping or gluing.
In some embodiments, the biasing member may be a conical coil spring, a coil spring, or other form of spring.
In some embodiments, the housing may further comprise a hole configured to allow insertion of a device (such as a surfactant delivery device or a suction tube) therethrough.
In some embodiments, when the housing comprises a hole, sealing means are provided, which are configured to prevent the flow of gas through the opening and allow the insertion of a device therethrough while providing gas to the patient.
In one embodiment, the sealing means may be a duckbill valve, however other forms of valve may be suitable.
In some embodiments, the opening may be located at any suitable location on the housing, and in one arrangement the housing is substantially aligned with the outlet on the opposite side of the chamber.
In some embodiments, the vent may include a valve seat that extends radially and engages a radial peripheral surface of the actuator when in the seated position such that an engagement area between the valve seat and the radial peripheral surface is within a radial dimension in the range of 0.2mm to 2.0 mm.
In some embodiments, the actuator may be relatively rigid such that the actuator uniformly disengages the valve seat when moving from the seated position.
In some embodiments, the actuator may be formed of any suitable material, including thermoplastic elastomers such as polyurethane, silicone, or rubber.
In an eighth aspect, the present disclosure provides a respiratory system for facilitating delivery of a gas to a patient, the respiratory system comprising at least one apparatus according to the seventh aspect, a gas flow source configured to supply a flow of gas, and a patient interface configured to engage with the patient.
In some embodiments, the gas stream source may provide a gas stream having a flow rate in the range of about 1L/min to about 150L/min, or about 20L/min to about 70L/min, or up to about 50L/min, or up to about 30L/min.
In some embodiments, the gas stream source may provide a gas stream having a flow rate in the range of about 5 to 15L/min.
In some embodiments, the respiratory system may include a controller for controlling the flow of gas supplied to the device from a source of gas flow.
In some embodiments, the controller may receive input indicative of pressure in the patient's airway and adjust control of the source of the gas flow to set Peak Inspiratory Pressure (PIP).
In some embodiments, the controller may receive input indicative of pressure in the patient's airway and adjust control of the source of gas flow to set Continuous Positive Airway Pressure (CPAP).
In some embodiments, the patient interface may be any suitable interface, such as a mask, an endotracheal tube, a laryngeal mask, or a nasal cannula.
In some embodiments, the respiratory system may further include a humidifier configured to condition the gas to a predetermined temperature and/or humidity prior to delivering the gas to the patient.
In some embodiments, the respiratory system may include a gas delivery conduit that provides other flows from a gas flow source to at least the patient interface.
In some embodiments, the respiratory system may include a plurality of devices.
In a ninth aspect, the present disclosure provides a pressure regulating device for facilitating regulation of pressure of a gas supplied to a patient, the device comprising:
A housing defining a chamber, the housing including an inlet couplable to a flow source providing a flow of gas to the chamber, an outlet couplable to a patient interface for supplying gas from the chamber to a patient, and a vent including an actuator for controlling the passage of gas from the chamber through the vent;
a biasing member biasing the actuator toward a seating position, wherein the actuator remains in the seating position until the pressure of the gas in the chamber exceeds a selected pressure level; and
An outlet member associated with the vent, wherein the outlet member includes a support member aligned with the vent axis, the actuator having an aperture formed therein that receives the support member such that the actuator moves along the support member when moved relative to the seating position.
In some embodiments, the support member may include a shaft within the aperture that extends through the actuator such that the actuator moves relative to the shaft.
Further features and advantages of the present disclosure will become apparent from the following detailed description.
Drawings
Various preferred embodiments of the present disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 illustrates an example of a respiratory system;
fig. 2 shows another example of a respiratory system;
FIG. 3 shows an example of a tee device in use with its PEEP orifice blocked;
FIG. 4 shows another view of the tee device in use with the PEEP orifice unblocked;
FIG. 5 shows another example of a tee device in use with its PEEP orifice blocked;
FIG. 6 shows another view of the tee device in use with the PEEP orifice unblocked;
FIG. 7 illustrates the direction of gas flow in a tee arrangement;
FIG. 8 shows a cross-sectional view of a prior art PEEP valve;
Fig. 9 shows a cross-sectional view of a conventional PIP valve;
FIG. 10 illustrates a cross-sectional view of a valve according to an embodiment of the present disclosure;
FIG. 11 shows a cross-sectional view of the valve of FIG. 10 with the valve actuator lifted from its valve seat;
FIG. 12 shows an exploded perspective view of the valve of FIGS. 10 and 11 configured for use with a tee device;
FIG. 13 shows a cross-sectional side view of the valve and tee of FIGS. 10 and 11, with the valve coupled to the PEEP orifice of the tee device;
FIG. 14 shows a schematic cross-sectional view of a valve and parameters of its components;
FIG. 15 illustrates an exploded perspective view of another embodiment of a valve according to the present disclosure;
FIG. 16 shows the valve of FIG. 15 connected to a tee device;
FIG. 17 illustrates an exploded side perspective view of another embodiment of a valve according to the present disclosure;
FIG. 18 shows a perspective view of the valve of FIG. 17 configured to couple with a tee;
FIG. 19 shows a bottom perspective view of the body of the valve of FIGS. 17 and 18;
FIG. 20 shows a schematic cross-sectional view of the valve of FIGS. 17 and 18;
FIG. 21 shows a side view of the valve of FIGS. 17 and 18 after coupling to a tee;
FIG. 22 illustrates an exploded side perspective view of another embodiment of a valve according to the present disclosure;
FIG. 23 shows a perspective view of the valve of FIG. 22 configured to couple with a tee;
FIG. 24 shows a side view of the valve of FIGS. 22 and 23 after coupling to a tee device;
FIGS. 25, 26, 27 illustrate examples of using the valve of the present disclosure with a respiratory system including a CPAP interface;
Fig. 28, 29, 30 illustrate another example of using the valve of the present disclosure with a respiratory system including a CPAP interface;
FIG. 31 shows a comparison of pressure curves with and without auto PEEP;
FIG. 32 shows a comparison of pressure curves generated by a theoretical "perfect system" and by a respiratory system including a valve of the present disclosure;
Fig. 33 illustrates the pressure regulating effect of the present valve to compensate for unexpected leaks in the respiratory system.
Detailed Description
The present disclosure relates to various devices, systems, and methods suitable for use in a respiratory system arranged for delivering breathable gas to a patient. In at least one aspect, the present disclosure relates to a valve for a respiratory therapy system. In at least one aspect, the present disclosure provides a pressure regulating device for facilitating regulation of a pressure of a gas supplied to a patient.
Respiratory therapy referred to throughout this disclosure may be resuscitation therapy, such as infant or neonatal resuscitation therapy, positive airway pressure therapy (PAP), continuous positive airway pressure therapy (CPAP), bi-level positive airway pressure therapy, non-invasive ventilation, or another form of respiratory therapy. In some configurations, the system may provide bi-level positive airway pressure therapy to achieve infant resuscitation.
As used in this disclosure, "pressure therapy" may refer to the delivery of breathable gas to a patient at a pressure of at least greater than or equal to about 1cmH 2 O. The pressure therapy may be delivered to mimic the patient's natural respiratory cycle and/or to assist the patient's breathing according to the patient's respiratory cycle.
In some configurations, the breathable gas delivered to the patient is or includes oxygen. In some configurations, the breathable gas includes oxygen or a mixture of oxygen-enriched gas and ambient air. In some configurations, the percentage of oxygen in the delivered gas may be between about 20% and about 100%, or between about 30% and about 100%, or between about 40% and about 100%, or between about 50% and about 100%, or between about 60% and about 100%, or between about 70% and about 100%, or between about 80% and about 100%, or between about 90% and about 100%, or 100%. In at least one configuration, the delivered gas may have an atmospheric composition. In at least one configuration, the gas delivered may be ambient air.
In the case of infant resuscitation, the lungs of the fetus are filled with fluid and oxygen comes from the blood vessels of the placenta when in utero. At birth, with the assistance of the birth canal's compression of the lungs, a transition is made to continuous post-natal respiration. Surfactants within the alveoli can also assist the infant in breathing to reduce surface tension, thereby preventing the alveolar walls from adhering to each other.
Any neonate may need respiratory assistance at birth to initiate or improve breathing. However, several factors may predict the need for resuscitation or respiratory assistance during a post-partum continuous respiratory transition. For example, childbirth of less than 35 weeks of gestational age, evidence of severe fetal damage, maternal infection or congenital anomalies, and an urgent caesarean section are all associated with an increase in respiratory assistance requirements at birth.
1. Summary of the invention
Fig. 1 shows an example of a respiratory system 1. Fig. 2 shows another example of a respiratory system 1. The respiratory system 1 is configured to provide respiratory therapy to a patient by delivering breathable gas to the airway of the patient.
In general, respiratory system 1 includes a respiratory apparatus 100, a conduit assembly 200 arranged to deliver breathable gas from respiratory apparatus 100 to a patient, and a patient interface 340 arranged to communicate with an airway of the patient. Some respiratory systems may also include a device 320 configured to be fluidly connected to the patient interface 340 when delivering respiratory therapy. In at least some embodiments, the device 320 includes a suitable connector to allow it to be fluidly coupled at one end to an inlet of the patient interface 340 and at the other end to a connector of the catheter assembly 200.
Referring to fig. 1, respiratory therapy apparatus 100 may include a flow generator 110, an optional humidifier 120 for humidifying the gas generated by flow generator 110, and an associated controller 130 that manages the operation of flow generator 110 and/or humidifier 120 (when present). In at least one embodiment, the flow generator 110 may be in the form of a blower.
Respiratory therapy device 100 may also include a transmitter 150, a receiver 150, and/or a transceiver 150 to enable controller 130 to receive signals emitted from sensors 30, 31, 32, 33 and/or to control various components of respiratory system 1, such as flow generator 110, humidifier 120, humidifier heating element 220, or accessories or peripherals associated with respiratory therapy device 100.
Fig. 2 shows another example of a respiratory system 1 comprising a respiratory therapy apparatus 100, which may be a positive airway pressure device, such as a resuscitator. An example of a resuscitator is the Neopuff TM infant resuscitator of the fischere healthcare (FISHER AND PAYKEL HEALTHCARE). The respiratory therapy apparatus 100 receives a flow of breathable gas from a gas supply 160 via a gas inlet. The respiratory therapy apparatus 100 may be connected to an optional humidifier 120 via a gas outlet of the apparatus 100. The humidified, breathable gas is then supplied to the patient from the outlet of the humidifier 120 via the conduit assembly 200 and the device 320 (connectable to a patient interface (not shown)). The gas supply 160 typically supplies a flow of breathable gas to the breathing apparatus 100 at a substantially constant flow rate. The respiratory device 100 receives a flow of breathable gas and is generally configured to set a pressure level to be delivered to a patient during an initial calibration phase. The pressure level may be PIP and/or PEEP.
As mentioned above, the device 320 is provided for the respiratory system 1 and, when in use, fluidly connects the catheter assembly 200 to the patient interface 340. In some existing respiratory systems, the device 320 is used by an operator of the system to manually adjust the pressure of the gas delivered to the patient, as illustrated in fig. 3-6.
Referring to fig. 3-6, each apparatus 320 includes an inlet 324 arranged to receive breathable gas from the breathing apparatus 100. The outlet 325 of the device 320 is arranged to be fluidly connected to the patient interface 340 when delivering respiratory therapy. Each device 320 also includes a PEEP vent 322 that is arranged to be occluded or unblocked by an operator's finger or digit when delivering respiratory therapy to a patient. When the PEEP vent 322 is blocked by the operator, the breathable gas received from the breathing apparatus 100 is delivered to the patient via the patient interface 340, and the respiratory system 1 delivers the breathable gas to the patient at a second pressure. When the occlusion is removed from the PEEP vent 322, the PEEP vent 322 allows gas from within the ventilator 1 to vent from the interior cavity of the device 320 to ambient air, and the ventilator 1 delivers breathable gas to the patient at a first pressure. In this way, resuscitation of the patient may be attempted by varying between the first pressure and the second pressure at a selected respiration rate.
Fig. 7 illustrates the direction of flow of breathable gas as it enters the device 320 via the inlet 324 of the device and exits the device 320 from the PEEP vent 322 (if it is not plugged) and/or from the outlet 325 (which is connected to the patient interface 340 in use). An optional valve 323 (such as a duckbill valve) may also be included in the device shown in fig. 5 and 6, which may be used to insert auxiliary equipment (such as a cannula for fluid removal or surfactant delivery), or a gas detection device (such as a CO 2 detector).
The configuration of the device 320 in fig. 3-6 allows for one-handed manual operation during resuscitation therapy. Over time, the pressure change of the breathable gas delivered to the patient may be represented by a generally square waveform, as shown in the upper right hand corner of fig. 3-6.
In some embodiments, the first pressure level is delivered at or near the patient terminal 26 at a first time or during a first time window. Once interface adaptation is confirmed, the first pressure level may be delivered at or near the patient terminal 26.
In one embodiment, the first pressure level is equal to the desired PEEP. The first pressure may be 1, 2,3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15cm H 2 O, and the useful value may be selected between any of these ranges (e.g., about 1 to about 15, about 1 to about 14, about 1 to about 13, about 1 to about 12, about 1 to about 11, about 1 to about 10, about 1 to about 9, about 1 to about 8, about 1 to about 7, about 1 to about 6, about 1 to about 5, about 2 to about 8, about 2 to about 6, about 2 to about 5, about 3 to about 8, about 3 to about 5, about 4 to about 8, about 4 to about 7, about 4 to about 5, about 5 to about 8, or about 6 to about 8cm H 2 O). The first pressure may be about 5cm H 2 O, but may also be set according to, for example, patient requirements and/or clinician preferences.
Similarly, the second pressure level may be delivered at or near the patient terminal 26 at a second time or during a second time window. Once the interface fitting is confirmed and/or once a given second pressure level is confirmed in the resuscitator 100, the second pressure level may be delivered at or near the patient terminal 26, for example by sealing the outlet of the device 320 with a protective cover (e.g., during an initial calibration phase). The respiratory system 1 continuously provides the patient with breathable gas at first and second pressure levels to mimic the patient's respiratory cycle. Typically, for an infant or child patient population, the patient is provided with 30-60 respiratory cycles/min during respiratory therapy. In some applications, the patient's respiratory cycle is manually determined by a clinician. It will be appreciated that the number of respiratory cycles/minute required will depend largely on the type of therapy to be provided to the patient, the condition of the patient (age, respiratory condition), and may vary from patient to patient, or based on different hospital protocols.
In at least one embodiment, the second pressure level is equal to the desired PIP. The second pressure may be 15、16、17、18、19、20、21、22、23、24、25、26、27、28、29、30、31、32、33、34、35、36、37、38、39、40、41、42、43、44、45、46、47、48、49、50、51、52、53、54、55、56、57、58、59、60cm H2O, and may be selected to be a useful value (e.g., about 15 to about 60, about 20 to about 25, about 21 to about 30, about 21 to about 27, about 21 to about 25, about 22 to about 30, about 22 to about 29, about 22 to about 25, about 23 to about 30, about 23 to about 28, about 23 to about 26, about 24 to about 30, about 24 to about 29, about 24 to about 28, about 24 to about 26, or about 25 to about 30cm h2 o) between any of these ranges. The first few respiratory cycles (to clear the airway of fluid and begin pulmonary ventilation) and/or if the patient does not respond positively to the originally administered respiratory therapy, a higher PIP may be required. In addition, the level of pressure required for resuscitation will typically vary from patient to patient depending on the presence of factors such as lung maturity, lung disease, condition and the like. The above-mentioned pressure ranges are for reference only, and in practice, the pressure may be adjusted individually according to the patient's reaction.
In at least one configuration, the patient interface 340 may be in the form of a sealed patient interface. In at least one configuration, patient interface 340 may be in the form of a respiratory mask, or an endotracheal tube, or a laryngeal mask. Patient interface 340 may be configured to deliver breathing gas to the airway of a patient via a seal or cushion at patient terminal 26. The patient interface 340 is intended to form an airtight seal in or around the nose and/or mouth of the patient. Patient interface 340 may be an oral-nasal interface, a direct nasal interface, and/or an oral patient interface that forms a substantially airtight seal between patient terminal 26 and the patient's nose and/or mouth. In at least one embodiment, the seal or cushion may be held in place on the patient's face by a headgear. In at least one embodiment, the patient interface 340 may be held on the patient's face by an operator (which may be a healthcare professional). Such sealed patient interfaces may be used to deliver pressure therapy to a patient. Alternative patient interfaces, such as those including nasal prongs, may also be used. In some examples, the nasal prongs may be sealed or unsealed. In at least one embodiment, the patient interface is a CPAP interface, such as the interface described in WO 2021176338 A1, the entire contents of which are incorporated herein by reference.
The neonatal interface may be any interface, such as the interfaces described above that are configured for infants or newborns. The neonatal interface may be configured to seal at least partially and preferably substantially around the nose and mouth of the patient.
In order to provide respiratory therapy to a patient, the pressure delivered to the patient needs to be regulated within a range to ensure the effectiveness of the respiratory therapy and at the same time prevent injury to the patient. This is particularly important because of the weaknesses in the lungs and airways of infants and neonates. In the past, a variety of different valves have been used to achieve this pressure regulation. For example, for the respiratory system 1 illustrated in fig. 2, the PEEP vent of the device 320 may include a pressure regulating valve (not shown) that allows gas from within the respiratory system 1 to vent to the outside and reduce any overpressure within the respiratory system 1. Such pressure regulating valves are commonly referred to as PEEP valves. A pressure regulating valve may also be provided in the breathing apparatus 100 of fig. 2 to set the pressure of the breathable gas delivered to the patient at the PIP. This is commonly referred to as a PIP valve. Additionally, a maximum pressure relief valve may also be provided in the breathing apparatus 100 to set the maximum pressure that may be delivered to the patient. In infant or neonatal respiratory therapy systems, the maximum pressure bleed may be set to about 40cm H 2 O.
Fig. 8 shows a schematic cross-sectional view of a known PEEP valve 40. In use, PEEP valve 40 allows gas to flow through valve 40 and exit the respiratory system in the direction indicated by the arrow. The PEEP valve 40 is used to provide manual pressure adjustment as previously described with reference to fig. 3-6. That is, when the PEEP vent 422 is blocked, the PEEP valve 40 closes and prevents air from flowing through the valve 40. When the plug is removed from PEEP vent 422, valve 40 opens to allow gas to flow through the valve in the direction indicated by the arrow. Such PEEP valves 40 provide a fixed flow restriction to the gas required to flow through the valve 40. In some existing PEEP valves 40, the flow restriction created by the valve is adjustable by twisting the outlet member 401 of the valve to adjust the vertical distance between the inner edge 402 of the outlet member and the gas inlet 403 of the valve 40. Springs may be included to prevent accidental or unintended changes in PEEP levels during operation. Although this device may be referred to as a "valve," its operation is the same as a manually operated fixed flow restriction device and will not close at any time during operation unless an operator manually blocks its outlet 422 to switch between PEEP and PIP.
Fig. 9 shows a cross-sectional view of a known PIP valve 50. PIP valve 50 includes a plunger 501 biased toward a gas inlet 504 of valve 50 by a spring 502. The lower end of the plunger 501 includes a flat region 503. During delivery of bi-level resuscitation therapy, plunger 501 remains seated on the valve seat when PEEP is delivered and is lifted off the valve seat to a fixed distance when PIP is delivered. Because plunger 502 sits on the valve seat, PIP valve 50 does not provide any pressure regulating effect during PEEP delivery. Additionally, PIP valve 50 is typically located within resuscitator device 100 and upstream of the location where gas is delivered to the patient, controlled by the controller of resuscitator device 100, and therefore the valve is generally not affected by changes in flow (e.g., leakage or increased flow caused by patient respiration) that typically occur near the patient's end.
The present disclosure is directed to a valve configured to respond to and compensate for flow changes experienced by the respiratory system, as will be described further below.
2. Valve
According to an aspect of the present disclosure, a valve for the respiratory system 1 described above is provided. The valve assists in regulating the pressure of the gas supplied to the patient. In at least some embodiments, the valve assists in regulating the PEEP pressure provided to the patient such that the gas pressure delivered to the patient remains within a predetermined pressure range (i.e., PEEP pressure range). In at least some embodiments, the valve can be configured to assist in regulating the PIP pressure provided to the patient such that the gas pressure delivered to the patient remains within a predetermined pressure range (i.e., PIP pressure range). According to the present disclosure, the valve achieves its pressure regulating effect by acting as a variable flow restrictor for the respiratory system 1 as the biasing member of the valve reacts to flow and pressure changes that are not considered during the initial calibration phase of the respiratory therapy apparatus but are typically experienced by the respiratory system 1 near the patient end. The valve provides continuous mechanical adjustment of the flow restriction based on the instantaneous gas pressure at the valve inlet without any manual or controller intervention. The flow restriction created by the valve is at least partially determined by the position of the actuator relative to the valve seat, as will be described further below.
Fig. 10, 11, 12, 13 illustrate various views of one embodiment of a valve 60 according to the present disclosure.
Referring to fig. 10, the valve 60 includes a valve body 620 defining an inlet 621 through which a flow of gas can enter and exit the valve 60 when the valve is open, and an outlet 622 through which the flow of gas exits the valve. In its simplest form, the valve body 620 may comprise a chamber with one end of the chamber comprising an inlet 621 and the other end of the chamber comprising an outlet 622. In the illustrated embodiment, the valve body 620 includes at least a housing 624 and an outlet member 625 configured to be coupled to the housing 624 via a suitable coupling (e.g., screw threads or a press fit).
The actuator 610 is housed within the valve body 620 in a space formed by the housing 624 and the outlet member 625. In other embodiments, the housing 624 and the outlet member 625 may be permanently connected or integrally formed together without a coupling therebetween. In the illustrated embodiment, the coupling between the housing 624 and the outlet member 625 includes a threaded portion formed on an inner wall of the housing 624 and a corresponding threaded portion formed on an outer wall of the outlet member 625 extending into the housing 624. It should be appreciated that the coupling between the housing 624 and the outlet member 625 may be provided in alternative forms and is not necessarily limited to a threaded coupling as illustrated. In at least some embodiments, this coupling allows housing 624 and outlet member 625 to be removably coupled to one another. The relative positions of the housing 624 and the outlet member 625 may also be adjusted by this coupling. For example, when a threaded coupling is used, the outlet member 625 may be twisted relative to the housing 624 to gradually linearly increase or decrease the height of the interior space of the valve body 620.
In one form, the housing 624 includes a substantially hollow body, which may be formed in a cylindrical shape. At or toward the lower end of the housing 624, the diameter of the cylindrical body decreases, allowing the inner wall of the housing 624 to form a valve seat 623 for the actuator 610 and to determine the seated position of the actuator 610.
The outlet member 625 may engage the housing 624 at its upper end. As shown in fig. 12, the outlet member 625 may be formed in a circular shape, including at least one aperture 628 at or near the center of the outlet member 625. In some embodiments, a plurality of apertures 628 may be formed in the outlet member 625. Orifice 628 forms outlet 622 of valve 60.
In some embodiments, the shaft 650 is also housed within the valve body 620 and aligned with the direction of movement of the actuator 610. This direction of movement may be considered as the venting axis of the valve 60. As illustrated, the shaft 650 may have an elongated shape with a lower end received in an aperture of the actuator 610. The aperture may be formed at or near the center of the actuator 610.
In at least one embodiment, the shaft 650 may be formed as an elongated rod having a circular cross-section in the lateral direction. The aperture of the actuator 610 may be configured to have a shape that is different from the cross-sectional shape of the shaft 650. For example, a square aperture may be formed in the actuator 610 into which the shaft 650 extends such that a small gap exists between the shaft 650 and the actuator 610. The apertures may be provided in other shapes having contours and/or dimensions that differ from the cross-sectional shape of the shaft 650. In some embodiments, the aperture of the actuator 610 may have the same shape as the cross-sectional shape of the shaft 650, but may be larger in size such that there is a gap between the shaft 650 and the actuator 610 when the shaft 650 extends into the actuator 610. A small clearance is provided between the shaft 650 and the actuator 610 to help reduce friction as the actuator 610 moves along the shaft 650 and to achieve controlled leakage through the clearance.
In some embodiments, the aperture of the actuator 610, and the shaft 650 are configured to reduce leakage of gas through a gap formed between the shaft 650 and the actuator 610. In these embodiments, the gap may have a width in the range of 0.025 to 0.15mm, such that any gas flow through the gap is negligible.
The upper end of the shaft 650 may be supported by an outlet member 625. For example, the outlet member 625 may include one or more arms 627 that are positioned within the outlet 622 and extend radially outward from the center of the outlet member 625 to connect to the inner rim of the outlet 622. Thus, the spaces between adjacent arms 627 form one or more apertures 628. A receiver may be formed below the one or more arm joints to receive the upper end of the shaft 650. In one form, the receiver may be formed in a square shape or any other shape. In this way, the shaft 650 is fixed in a vertical orientation to help stabilize the movement of the actuator 610 along its vent axis. In at least one embodiment, the upper end of the shaft 650 can be directly connected to the one or more arms 627 or integrally formed with the one or more arms 627.
The shaft 650 is arranged to guide and stabilize the movement of the actuator 610 during pressure adjustment of the actuator. Without the shaft 650, the actuator 610 may flutter on the valve seat 623 when affected by factors such as the stiffness of the biasing member 630, the stability of the actuator 610, and rapid pressure changes within the respiratory system 1. When the actuator 610 vibrates, noise and internal pressure oscillations may be generated. The shaft 650 assists in stabilizing the actuator by allowing the actuator 610 to slide in a vertical direction along the axis of the shaft 650 while minimizing any lateral movement.
The actuator 610 may be configured to have a substantially planar lower surface. In one form, the actuator may include a circular disk 611 that includes a substantially planar lower surface. The peripheral region of the circular disk 611 is configured to engage or rest on the valve seat 623, as indicated in fig. 10. A significant portion of the flat lower surface of the circular disk 611 is configured to be exposed to gas at the inlet 621 of the valve 60, allowing the gas pressure to apply an upwardly directed, uniformly distributed lifting force (F Lifting up ) to the exposed area of the circular disk 611. In some embodiments, the actuator 610 further includes a portion 612 that is raised relative to the upper surface of the actuator 610. The raised portion 612 engages the lower end of the biasing member 630, for example, by extending into the interior volume of the biasing member 630. The upper end of the biasing member 630 engages the lower surface of the outlet member 625. In some embodiments, a similar raised portion 626 may also be provided to the lower surface of the outlet member 625 to assist in maintaining the position of the biasing member 630 within the valve body 620. In alternative forms, the actuator 610 may be configured differently from the illustrated embodiment and does not necessarily have a flat lower surface.
In fig. 10, the actuator 610 is biased by a biasing member 630 toward the inlet 621 of the valve 60. In at least some embodiments, the biasing member 630 can be a spring, such as a coil spring comprising a plurality of coils. In at least one embodiment, the biasing member is a conical coil spring. That is, the coils at one end of the spring are configured to have a different coil size than the coils at the other end of the spring. The size of the windings may increase gradually from one end of the spring to the other. In some embodiments, the coils of the conical spring may increase in size from one end of the engagement actuator 610 to one end of the engagement outlet member 625. In some embodiments, a conical spring may be preferred so that the spring does not significantly affect the flow resistance and provides a degree of lateral stability to the valve 60.
The biasing member 630 is maintained in a compressed state in the valve body 620. That is, the height of the biasing member 630 in FIG. 10 is less than the uncompressed natural length of the biasing member 630. Since the biasing member 630 has been compressed, it applies a resistance force (F Bias of ) to the actuator 610 to urge the actuator 610 toward the inlet 621 of the valve 60 until it engages the valve seat 623. When in this seated position, the actuator 610 closes the gas flow path between the inlet 621 and the outlet 622 of the valve body 620, thereby minimizing any gas flow through the valve 60. The resistance generated by the biasing member may be calculated from F Bias of =k (x_initial compression+x_lift), where:
K=spring constant of the spring;
x_initial compression = initial compressed length of the spring when the flow path is closed (i.e., the difference between the original uncompressed length of the spring and the length of the spring after it was initially compressed and placed within the valve body 620);
x_lift = displacement of actuator 610 from valve seat under pressure P.
It will be appreciated that the resistance generated by the biasing member is a variable resistance due to the x_lift (which may vary with the variation of the pressure level P). When the actuator 610 is biased against the valve seat 623, the x_lift is equal to 0 because the actuator 610 has not been relatively displaced from the valve seat 623. The initial variable resistance applied by the biasing member 630 may be reduced to F Bias of =kx_initial compression. When the actuator 610 is lifted off the valve seat 623 and begins to slide along the shaft 650 with the valve body, the x_lift is equal to the displacement distance of the actuator 610 relative to the valve seat 623, which distance is variable. That is, the variable resistance varies according to the movement of the actuator 610, which changes the compression of the biasing member 630.
In addition to the variable resistance force (F Bias of ) applied by the biasing member 630, the actuator 610 is also subjected to an opposite upward lifting force (F Lifting up ) due to the area of the actuator 610 exposed to the gas at the inlet of the valve 60. The lifting force depends on the pressure level P at the inlet 621 and the area of the actuator exposed to the pressure (F Lifting up =p×a). Accordingly, the position and movement of the actuator 610 relative to the valve seat 623 is determined by the relative strengths of the two forces F Bias of and F Lifting up .
Using the equation mentioned above, the minimum pressure required to lift the actuator 610 off the valve seat 623, which is greater than kxx—initial compression/a, can be determined. The minimum pressure level determines the selected pressure level at which the valve 60 is opened, and the predetermined pressure range within which the valve 60 is configured to regulate. It should be appreciated that during delivery of breathable gas to a patient, as the flow of gas through valve 60 changes, the pressure level at inlet 621 may fluctuate, e.g., an increase in the flow of gas through valve 60 will increase the pressure level at inlet 621, while a decrease in the flow of gas through valve 60 may decrease the pressure level at inlet 621.
If the gas pressure of the respiratory system 1 is below the selected pressure level, F Lifting up is insufficient to lift the actuator 610 off the valve seat 623. Accordingly, the net effect of these two forces maintains the actuator 610 in its seated position on the valve seat 623 (F Bias of ≥F Lifting up ). As the gas pressure at inlet 621 begins to increase, it translates into an increased F Lifting up . As the gas pressure reaches or exceeds the selected pressure level such that F Lifting up is greater than F Bias of , the lifting force will overcome the variable resistance force (F Lifting up >F Bias of ) exerted by the biasing member 630 and lift the actuator 610 above the valve seat 623, as indicated in fig. 11.
As the actuator 610 is lifted off the valve seat 623, a gap is formed between the outer peripheral region of the actuator 610 and the valve seat 623. The gas flow may then begin through the gap into the valve body 620 and out of the valve via the outlet 622. In other words, the gas flow path between the inlet 621 and the outlet 622 of the valve body 620 is now open, and the gas within the respiratory system 1 may now exit via the valve 60 in the direction indicated by the arrow in fig. 11. If the gas pressure is at or above the selected pressure level, and the gas pressure further increases (e.g., due to an increase in gas flow through the valve 60), the F Lifting up continues to displace the actuator 610 in an upward vertical direction even though the actuator 610 has been lifted off the valve seat 623. This will increase the clearance between the actuator 610 and the valve seat 623, allowing air to enter the valve body 620 and be expelled to the outside, and limit the pressure increase to substantially maintain the gas pressure at a selected pressure level. At the same time, lifting of the actuator 610 causes the biasing member 630 to compress further (which increases the variable resistance created by the biasing member 630) until it reaches an equilibrium position, where F Lifting up is equal to F Bias of , at which point the actuator 610 is not displaced further away from the valve seat 623. The actuator 610 is maintained at this position to discharge the gas flow to the outside until the gas pressure is changed again.
If the gas pressure decreases (e.g., due to a decrease in the flow of gas through the valve 60) and the gas pressure is still at or above the selected pressure level, F Lifting up is less than F Bias of , so the net effect of these two forces will begin to move the actuator 610 closer to the valve seat 623. This movement will reduce the size of the flow path within the valve 60, allowing the gas flow to vent to the outside to limit pressure drop and substantially maintain the gas pressure at the selected pressure level. The actuator 610 is maintained at this position to discharge the gas flow to the outside until the gas pressure is changed again.
As can be seen from the foregoing, the operation of the valve 60 differs from conventional pressure relief valves which temporarily open to reduce excessive pressure and then remain closed after the excessive pressure is released. In contrast, the valve 60 of the present disclosure acts as a mechanical pressure regulating device that assists in maintaining the gas pressure at the inlet of the valve 60 within a predetermined pressure range. More specifically, the pressure regulating effect is achieved by allowing the valve 60 to open and remain open, so long as the pressure at the inlet of the valve 60 is above a predetermined pressure level. When used for infant resuscitation, it is contemplated that the valve 60 will remain open throughout PEEP delivery and will open to a greater extent (i.e., the actuator 610 is displaced farther from the valve seat 623) if it is desired that the valve 60 allow a higher flow of gas through the valve 60.
The valve 60 of the present disclosure may be used in conjunction with a tee device 320 to regulate the pressure of gas delivered to a patient. Fig. 12 shows an exploded perspective view of the valve 60 and tee arrangement 320. Fig. 13 shows a cross-sectional side view of the valve 60 and tee arrangement 320 when all components are connected. In this embodiment, the housing 624 of the valve 60 may be integrally formed with the tee arrangement 320. In other embodiments, the valve 60 may be detachably connected to the tee device 320 or another component of the respiratory system 1 via an adapter, as will be described further below.
The configuration of the tee arrangement 320 is substantially similar to the arrangement 320 shown in fig. 3-6. The tee arrangement 320 includes an inlet 324 arranged to receive a flow of breathable gas from a source of gas flow (e.g., the respiratory apparatus 100). The outlet 325 of the device 320 is arranged to be connected to a patient interface (not shown) when delivering respiratory therapy. An optional valve 323 (such as a duckbill valve) may be provided, which may be used to insert auxiliary devices, such as a cannula for fluid removal or surfactant delivery, or a gas detection device, such as a CO 2 detector. The device 320 also includes a vent, referred to as a PEEP vent, and the valve 60 is provided to the PEEP vent to act as a pressure regulating valve for the tee device 320.
The valve 60 and tee arrangement 320 may be used to regulate the pressure of gas delivered to the patient during bi-level resuscitation. More specifically, the valve 60 and tee device 320 may be used to regulate PEEP pressure delivered to a patient as follows.
As previously mentioned, when delivering bi-level resuscitation therapy, the gas pressure delivered to the patient is switched between PEEP and PIP depending on the desired respiratory rate to be provided to the patient. After an initial calibration procedure, the respiratory system 1 may be arranged to enter a delivery mode and provide a source gas flow to the patient at a substantially constant gas flow rate, as previously described with respect to fig. 2. When used to regulate PEEP pressure, the valve 60 may be configured such that when the pressure reaches a selected pressure level, which is within the range of PEEP pressures to be provided to the patient, the actuator 610 is lifted off the valve 623 and the gas flow path between the inlet 621 and the outlet 622 is opened. For example, for infants or newborns, the target PEEP pressure range may be about 5cm h2o, ranging from-2 to +2cm h2o. That is, the predetermined and acceptable PEEP pressure range may be about 3 to 7cm h2o. In this case, the selected pressure level (at which the actuator 610 is lifted off the valve seat 623) may be set to 3.5 to 4.5cm h2o, which is within the predetermined PEEP pressure range. This ensures that valve 60 remains open during PEEP delivery as long as the pressure is above the selected pressure level. It will be appreciated that for infant or neonatal patients, the target PEEP pressure range may be in the range of 5cm to 15cm h2o, for example 6, 7, 8, 9, 10cm h2o.
The respiratory system 1 may experience flow changes due to accidental leaks or patient breathing (e.g., resulting in automated PEEP), which typically requires venting of either less or more of the gas flow to the outside via the valve 60. Patient respiration refers not only to spontaneous breathing of the patient, but also to other inspiratory and expiratory flows of the patient that may potentially cause pressure changes within the respiratory system 1, for example, during assisted ventilation. In the event of an unexpected leak, the pressure within the respiratory system 1 may decrease, which reduces the lifting force applied to the actuator 610 in an upward direction. Accordingly, the actuator 610 may be moved closer to the valve seat 623 to reduce the size of the gas flow path between the inlet and outlet of the valve. This will limit the pressure drop so that the pressure is maintained substantially at the selected pressure level (within the predetermined PEEP pressure range). Alternatively, if the pressure drops below a selected pressure level of 3.5 to 4.5cm h2o, the actuator 610 may seat on the valve seat 623 (as shown in fig. 10) to fully close the valve 60.
If the patient exhales during PEEP delivery, the patient may cause an increase in the gas flow in the respiratory system because the respiratory system 1 is set to deliver a fixed source gas flow, especially when using the respiratory system 1 of fig. 2. The increased gas flow can increase the gas pressure in the system and increase the lifting force in the upward direction. While the actuator 610 has been lifted off the valve 623, the increase in pressure will displace the actuator 610 further away from the valve 623, increasing the size of the flow path between the inlet 621 and the outlet 622 of the valve and letting out additional gas flow through the valve 60. In this way, the valve 60 is able to limit the increase in pressure to regulate the gas pressure so that it remains within the predetermined PEEP pressure range.
During PIP delivery, outlet 622 of valve 60 is arranged to be blocked, for example, by an operator's finger, to effectively close valve 60 regardless of the gas pressure within respiratory system 1. When PIP delivery is complete, the blockage may be removed from outlet 622, allowing valve 60 to again adjust PEEP pressure, as described above.
The configuration of the biasing member 630, the exposed area of the actuator 610 and the inlet of the valve 60 should be carefully determined and mutually adapted to each other so that the valve 60 is able to adjust the gas pressure when needed and to maintain the gas pressure of the respiratory system 1 within a predetermined PEEP pressure range.
Fig. 14 schematically shows structural components in the valve 60. As previously mentioned, the pressure regulation mechanism of valve 60 is determined by the relative intensities of F Lifting up and F Bias of . Thus, key parameters affecting the pressure regulation mechanism of valve 60 are: the gas pressure at inlet 621 (P), the area of the actuator 610 exposed to the gas pressure at the valve inlet (a), the initial compression of the biasing member (x_initial compression), the depth of the valve body 620 (which determines the potential maximum x_lift), and the spring constant (k). The spring constant of the biasing member 630 is also related to other parameters of the biasing member 630, such as the number of coils, the diameter of the wire of the coils, the spring pitch, etc.
While the above example is using bi-level resuscitation therapy as an example and the valve 60 is configured to regulate PEEP delivery pressure, it should be appreciated that the valve 60 may also be adapted to regulate another pressure range by selecting different parameters of the biasing member 630 and the exposed area of the actuator 610. As mentioned above, the pressure at which the actuator 610 is lifted off the valve seat 623 may be calculated from p=kx—initial compression/a. That is, once the pressure P is selected or known, the equation may be used to derive other parameters for the valve.
In addition to selecting an appropriate spring constant (k), initial compression of the spring (x—initial compression), and exposed area (a) of the actuator 610, there are other design considerations that help how the valve 60 can be configured, at least some of which are listed below.
Gas flow through valve 60: in order to regulate PEEP pressure, the valve 60 should be capable of regulating the flow of gas in the range of 5 to 15L/min when used on infants. For adult patients, the gas flow may be in the range of 1 to 150L/min, or in the range of 20 to 70L/min, or up to 50L/min, or up to 30L/min. This range may be approximately the same as the source flow that the respiratory system 1 is configured to provide to the patient.
Predetermined range of PEEP pressures: for infant resuscitation, the target PEEP pressure is typically in the range of 4 to 15cm h2 o. The valve 60 should be configured such that it is able to regulate the gas pressure within the respiratory system 1 such that it remains within this range. In some embodiments, valve 60 is configured to regulate the pressure of the breathable gas within respiratory system 1, ranging from-2 to +2cm H 2 O, -1 to +1cm H 2 O, or-0.5 to +0.5cm H 2 O. That is, if respiratory system 1 is set to deliver PEEP to a patient at a given flow rate and a target PEEP pressure of 5cm H 2 O, valve 60 is configured to regulate the PEEP pressure such that, regardless of the system experiencing any flow rate change, the pressure remains in the range of 3 to 7cm H 2 O, or 4 to 6cm H 2 O, or 4.5 to 5.5cm H 2 O at the given flow rate.
Depth of valve: the depth (D) of the valve 60 at least partially determines the initial compression length (x_initial compression) of the biasing member 630 and the maximum x_lift that can be achieved. In at least one embodiment, the depth of the valve is approximately 3 to 6mm.
Configuration of biasing member 630: the configuration of the biasing member includes selection of appropriate spring constants, spring wire diameters, the size of the spring coils, the number of spring coils, the spring pitch, etc. In at least one embodiment, the spring constant is less than 0.05N/mm. Preferably, the spring constant is in the range of 0.005 to 0.02N/mm.
An actuator: the exposed area (a) of the actuator 610 and the size (d_v) of the valve inlet 621 may be selected such that the pressure at which the valve 60 is opened and the valve regulated pressure are similar. In at least some embodiments, the cross-sectional area of the actuator 610 or the cross-sectional area of the exposed area (a) of the actuator 610 is between 50 and 320mm 2. In other embodiments, the cross-sectional area of the actuator 610 or the cross-sectional area of the exposed area of the actuator 610 may be in the range of 100 to 250mm 2, or in the range of 120 to 200mm 2, or in the range of 140 to 180mm 2. In one embodiment, the exposed area (a) may be, for example, about 160mm 2 when the actuator 610 is in the sitting position. In some embodiments, the actuator 610 may be made of a relatively rigid material (such as polyurethane) to reduce the likelihood of the actuator 610 flexing. However, other materials (e.g., thermoplastic elastomer materials such as silicone or rubber) may also be suitable.
Furthermore, the exposed area and spring constant of the actuator 610 are mutually selected such that a relatively small displacement (i.e. in the mm range, or a fraction of a millimeter) of the actuator 610 relative to the valve seat 623 is sufficient for the valve 60 to achieve its pressure regulating effect. That is, the relationship between the exposed area of the actuator 610 and the spring constant of the biasing member 630 determines the pressure adjustment effect described above. Because of this relationship, the relatively small displacement that occurs to actuator 610 limits the increase and decrease in pressure (caused by the increase and decrease in gas flow through device 320 and valve 60, respectively, as described above) to thereby regulate the gas pressure to be maintained at a selected pressure level (e.g., within a predetermined target PEEP pressure range).
Since a relatively small displacement of the actuator 610 may be sufficient to allow the valve 60 to achieve its pressure regulating effect, the actuator orifice may be formed as a blind hole (i.e., rather than a through hole) that receives the lower end of the shaft 650.
The cross-sectional area of the actuator 610 is preferably smaller or substantially smaller than the inner lateral dimension of the valve body 620, so that there is no significant additional flow resistance as the gas passes between the inner sidewall of the valve body 620 and the actuator 610. The resistance to flow through the valve 60 is primarily determined by the gap formed between the actuator 610 and the valve seat 623. The resistance to flow through the valve 60 is primarily determined by the displacement of the actuator 610 relative to the valve seat 623. In general, for a given gas flow rate through the valve 60, an increase in flow resistance through the valve 60 results in an increase in pressure, and conversely, a decrease in flow resistance through the valve 60 results in a decrease in pressure.
Flow consistency: the inlet 324 of the tee arrangement 320 may be the same size as the inlet 621 of the valve 60 to maintain a consistent flow between the inlet 324 of the tee arrangement and the inlet 621 of the valve 60 when the valve 60 is open.
Overlap of actuator 610 with valve seat 623: the overlap (O) between the actuator 610 and the valve seat 623 is preferably kept small to avoid potential "sticking" of components and to avoid creating additional flow restrictions. In at least one embodiment, the overlap O is in the range of 0.2mm to 3mm, or in the range of 0.2mm to 2mm, in the radial direction.
Fig. 15 and 16 illustrate another embodiment of a valve 60 according to the present disclosure. The configuration of the valve 60 is substantially similar to the embodiment illustrated in fig. 10, 11, with some modifications. Fig. 15 shows an exploded view of the components of the valve 60. The valve body 620 also includes a housing 624 and an outlet member 625 that are coupled to one another via a threaded coupling. Now, a threaded portion is formed on the outer wall of the housing 624 and a corresponding threaded portion is formed on the inner wall of the outlet member 625. After the valve 60 is connected to the tee arrangement 320, the housing 624 may extend partially into the outlet member 625.
A gripping structure 640 is formed on the outer surface of the outlet member 625. The gripping structure 640 may include an array of parallel ridges evenly distributed around the outer surface of the outlet member 625. The grip structure 640 may facilitate easier connection and disconnection of the valve 60 to the tee device 320. The outlet member 625 can also be used to adjust the initial compression of the biasing member 630 by twisting the outlet member 625 relative to the housing 624. For example, the outlet member 625 may be twisted to increase the height of the interior space created by the housing 624 and the outlet member 625, thereby reducing the initial compression of the biasing member 630. Alternatively, the outlet member 625 may be twisted to reduce the height, causing the biasing member 630 to be further compressed. By adjusting the initial compression of the biasing member 630, the target pressure range over which the valve 60 is arranged to adjust is also adjusted. As mentioned above, the selected pressure level at which the valve 60 is opened is determined by p=kx_initial compression/a. Once P is exceeded, valve 60 opens. When the biasing member 630 has a greater initial compression (by reducing the height of the interior space created by the housing 624 and the outlet member 625), the selected pressure level that opens the valve 60 is also higher. Similarly, when the biasing member 630 has less initial compression, the selected pressure level that opens the valve 60 also decreases.
Fig. 17, 18, 19, 20, 21 show various views of another embodiment of a valve 60. In the previous embodiments described above, the valve 60 may be at least partially integrally formed with the tee device 320. Fig. 17-21 illustrate another embodiment of a valve 60 that may be removably connected to a tee fitting 320, or another vent orifice of the respiratory system, as will be described further below.
In this embodiment, valve 60 includes an adapter 660 to allow valve 60 to be detached and reattached to other locations of respiratory system 1. Examples of such adapters are described in US 9808612 B2, the entire contents of which are incorporated herein. The adapter 660 includes a male connector portion 661 and a female connector portion 662 that are configured to engage one another to form a detachable connection. The male connector portion 661 includes a pair of locking fingers and is arranged to be received by the female connector portion 662. Female and male connector portions 662 and 661, respectively, may be provided for the valve 60 and PEEP vent 322 of the tee device 320 to facilitate easier coupling between the two components. Or alternatively, a male connector portion 661 may be provided for the valve 60 and a female connector portion 662 may be provided for the PEEP vent 322. Fig. 19 shows a female connector portion 662 that may be formed on an inner wall of the housing 624. The adapter 660 allows the valve 60 to be connected to the PEEP vent of the device 320 by simply pushing the housing 624 of the valve 60 toward the PEEP vent 322 until the male and female connector portions 661, 662 engage each other and form a connection. Fig. 21 shows the valve 60 coupled to the device 320 by this coupling mechanism. To detach the valve 60 from the device 320, the user may pull the valve 60 away from the device 320, which disengages the male and female connector portions 662, 661 from each other.
Fig. 22-24 illustrate yet another embodiment of a valve 60 configured to connect to a PEEP vent of a tee device 320. To facilitate easier connection of the valve 60 to the tee device 320, the housing 624 may be configured with a tapered profile such that an end of the housing 624 can be inserted directly into the PEEP vent of the tee device 320 to form the connection.
The detachable connection mechanism described above may also be used to reduce installation complexity and enable resuscitation therapy to be provided through a different interface (e.g., through an infant CPAP interface). An example of an infant CPAP interface is described in WO 2021176338 A1, the entire contents of which are incorporated herein. In some CPAP respiratory systems, the flow of exhaled gas is directed from the patient interface to a resistance device (such as a bubbler device) via an exhalation tube. The valve 60 of the present disclosure may be used to act as a resistance device in such CPAP breathing devices, in place of the previous bubbler device. The valve 60 may be beneficial in a CPAP respiratory system in that the valve 60 may maintain a consistent CPAP pressure as the patient breathes spontaneously (which causes the flow of gas through the valve to vary during inspiration and expiration). Fig. 25-27, 28-30 illustrate examples of using the valve 60 of the present disclosure with an infant CPAP interface to deliver resuscitation therapy to a patient.
Fig. 25-27 illustrate an exemplary CPAP respiratory system 1 in which a valve 60 of the present disclosure is used. The valve 60 may include a detachable connector 660 as previously described with reference to fig. 19-29. In the illustrated arrangement, the patient interface 340 receives an inspiratory gas stream via an inspiratory conduit 201 a. The flow of exhalation gas may be directed from interface 340 via exhalation conduit 201b to a variable flow resistance device, which in the illustrated arrangement is valve 60. An optional humidifier system 120 is provided to humidify the flow of the inspiration gas. The humidified flow of inspiratory gas is delivered to the airway of the patient by inspiratory conduit 201a and patient interface 340. Excess and expired gases are exhausted from the patient interface 340 through the exhalation conduit 201 b. Valve 60 provides a variable flow resistance to the flow of exhalation gas exiting system 1 to provide a desired patient pressure. In at least one embodiment, the valve 60 and respiratory system 1 may be configured to provide bi-level resuscitation therapy as previously described. In use, the outlet of valve 60 may be blocked so that respiratory system 1 delivers PIP to the patient. When the occlusion is removed, the respiratory system 1 delivers PEEP to the patient, and the valve 60 regulates the gas pressure delivered to the patient so that it remains within the predetermined PEEP range.
Fig. 28-30 illustrate another example of the use of the valve 60 of the present disclosure in combination with a tee device 320 for a CPAP respiratory system 1. Referring to fig. 28, an adapter 660 (male or female) may be provided to the inlet of the tee device 320, while a complementary adapter 660 may be provided to the exhalation tube 201b of the CPAP interface 340. This will allow a quick connection to be made between the tee 320 and the CPAP interface 340. In addition, another adapter 660 may be provided with the PEEP vent of the tee device 320, and the valve 60, to enable the valve 60 to be removably connected to the tee device 320, as in the previous embodiment. The outlet of the tee 320 is then covered with a protective cover so that all of the expiratory gas flow passes through the valve 60. This configuration may also be used to provide resuscitation therapy to a patient, for example, by blocking the outlet 622 of the valve 60 with a finger or digit to switch between PIP and PEEP.
Examples
In prior art systems, when there is excess gas in the respiratory system 1 due to patient breathing, the gas pressure at the inlet of the existing PEEP valve may increase and result in an automatic PEEP. Fig. 31 illustrates the effect of automated PEEP in the prior respiratory system and its effect on gas pressure, i.e., when increased gas flow passes through the valve 60 of the present disclosure, independent of the valve 60 for pressure regulation to maintain the gas pressure within a selected pressure. Two pressure curves are shown in fig. 31: an automated PEEP pressure curve and a target pressure curve showing the pressure level that should be reached during respiratory therapy. As can be seen in fig. 31, during PEEP delivery, the target pressure provided to the patient may be set to 5cm H 2 O when the breathing apparatus is set to deliver a constant gas flow of 8L/min. If at the end of the expiration period the patient still has an expiratory flow of 2L/min, the total flow that needs to be released is 10L/min. If a fixed flow restriction device (such as the previous PEEP valve shown in fig. 8) is used to vent the gas to the outside, the increased flow of 10L/min may have the effect of temporarily raising the pressure within the respiratory system to approximately 8.3cm H 2 O. Thus, rather than allowing the gas pressure to drop to the desired 5cm H 2 O, the actual pressure delivered to the patient in the event of an automated PEEP is higher.
The valve 60 of the present disclosure is configured to prevent or reduce pressure increases due to expiratory flow, which prevents or reduces the occurrence of automated PEEP events. If the pressure at the inlet 621 of the valve 60 is below the selected pressure level at which the valve 60 should be opened, the actuator 610 remains seated on the valve seat 623. When the gas pressure reaches or exceeds a selected pressure level, the actuator 610 is lifted off the valve 623, allowing the gas to flow through the valve 60 and be discharged to the outside. In the case of automatic PEEP, the gas pressure at the inlet 621 of the valve 60 may increase due to the additional flow of gas (increased flow of gas through the valve 60) caused by the patient's breathing. The increase in gas pressure is translated into an increased lifting force applied to the actuator 610 and displaces the actuator 610 farther away from the valve seat 623, thereby increasing the size of the gas flow path between the inlet and outlet of the valve 60. As described above, displacement of the actuator 610 from the valve seat 623 limits the increase in gas pressure to regulate and maintain the gas pressure at a selected pressure level (e.g., within a predetermined PEEP pressure range).
Figure 32 shows the pressure profile generated by a "perfect" system, where the PEEP pressure was maintained at 5cm H 2 O at any flow rate. In contrast, the PEEP pressure regulated by valve 60 is shown. The solid line illustrates that for flows above 2L/min, the system is always able to deliver more than 4.5cm H 2 O, with the pressure increasing slowly with increasing flow, more than 5cm H 2 O at 5L/min and approaching 5.8cm H 2 O at 15L/min. Even if the flow rate increases from 2L/min to 15L/min, the corresponding PEEP pressure change is only 4.5cm H 2 O to 5.8cm H 2 O. The shaded area represents the "working zone" where any point within the zone is an acceptable PEEP pressure at that flow rate. Fig. 32 shows that valve 60 limits any increase or decrease in gas pressure (caused by an increase or decrease in gas flow through device 320 and valve 60, respectively, between about 2L/min and about 15L/min) to thereby regulate the gas pressure to be maintained at a selected pressure level (within a predetermined target PEEP pressure range).
FIG. 33 shows the valve 60 response to leakage at input flow rates up to 12L/min. In the event of an unexpected leak (a decrease in the flow of gas through the valve 60) that causes a drop in the pressure of the gas at the inlet 621, the size of the gas flow path between the inlet and the outlet of the valve 60 is reduced to compensate for the pressure loss. The decrease in gas pressure translates into a decreased lifting force applied to the actuator 610 and displaces the actuator 610 closer to the valve seat 623, thereby decreasing the size of the gas flow path between the inlet and outlet of the valve 60. As described above, displacement of the actuator 610 from the valve seat 623 limits the decrease in gas pressure to regulate and maintain the gas pressure at a selected pressure level (e.g., within a predetermined PEEP pressure range). If the leak continues to increase to a level greater than about 10.5-11L/min when 12L/min is provided, resulting in a further drop in pressure in the respiratory system 1, the actuator 621 may return to its valve seat 623 and block gas flow through the valve 60.
In fig. 32, as the flow increases from 2L/min to 15L/min, the valve 60 needs to displace its actuator 623 farther away from the valve seat 623 to allow higher gas flow through the valve 60 while ensuring that the gas pressure remains within the PEEP pressure range. In contrast, when there is a leak, the flow of gas through the valve 60 is reduced while still maintaining the pressure within the PEEP pressure range. As shown in fig. 33, when the leakage level increases from 0L/min to about 10.5L/min, the delivered PEEP pressure only slightly decreases from 6cm H 2 O to 4.5cm H 2 O and is maintained at a selected pressure level within the predetermined PEEP pressure range at an input flow of 12L/min. The shaded area represents the "working zone" (predetermined PEEP pressure range) where any point within the zone is acceptable PEEP pressure at that input flow rate.
Positive end-expiratory pressure (PEEP) is also known as end-expiratory peak pressure, and these two terms are often used interchangeably in respiratory therapy systems and methods.
In this specification, such as left and right, top and bottom, hot and cold, first and second, etc., adjectives may be used to distinguish one element or action from another element or action, without necessarily requiring or implying any actual such relationship or order. Where the context allows, references to a component, integer, or step (etc.) should not be construed as limited to only one of the component, integer, or step, but may be one or more of the component, integer, or step.
In this specification, the terms "comprises," "comprising," "includes," "including," "containing," or similar terms are intended to mean a non-exclusive inclusion, such that a method, system, or apparatus that comprises a list of elements does not include only those elements but may include other elements not listed.
The previous description of the disclosed embodiments is provided for the purpose of providing a description to those skilled in the relevant art. The above description is not intended to be exhaustive or to limit the disclosure to the precise embodiments disclosed. As mentioned above, numerous alternatives and variations of the present disclosure will be apparent to those skilled in the art in light of the above teachings. Accordingly, while some alternative embodiments have been specifically discussed, other embodiments will be apparent to or can be developed relatively easily by those of ordinary skill in the art. The present disclosure is intended to cover all modifications, alternatives, and variations that have been discussed herein, as well as other embodiments that fall within the spirit and scope of the above description.

Claims (68)

1. A valve for a respiratory system arranged for delivering breathable gas to a patient, wherein the valve allows gas to be expelled from within the respiratory system, the valve comprising:
a valve body including an inlet and an outlet, the inlet configured to be in fluid communication with the respiratory system;
an actuator disposed within the valve body in a flow path between the inlet and the outlet,
Wherein the actuator is movable by the gas, the movement of the actuator being at least partially dependent on the gas pressure at the inlet, wherein the movement will adjust the flow path between the inlet and the outlet to adjust the gas pressure in the respiratory system to within a predetermined range.
2. The valve of claim 1, wherein the actuator is biased toward an inlet of the valve.
3. A valve for a respiratory system arranged for delivering breathable gas to a patient, wherein the valve allows gas to be expelled from within the respiratory system, the valve comprising:
a valve body including an inlet and an outlet, the inlet configured to be in fluid communication with the respiratory system;
an actuator disposed within the valve body in a flow path between the inlet and the outlet,
Wherein the actuator is biased towards the inlet and movement of the actuator away from the inlet is dependent at least in part on the gas pressure at the inlet, the movement adjusting the flow path between the inlet and the outlet to adjust the gas pressure in the respiratory system to within a predetermined range.
4. A valve as claimed in claim 1 or 3, wherein the actuator is caused to move away from the inlet when the pressure exceeds a selected pressure level.
5. A valve according to any one of the preceding claims, wherein the predetermined range is a predetermined PEEP pressure range.
6. The valve of claim 5, wherein the selected pressure level is within the predetermined PEEP pressure range.
7. A valve for a respiratory system arranged for delivering breathable gas to a patient, wherein the valve allows gas to be expelled from within the respiratory system, the valve comprising:
a valve body including an inlet and an outlet, the inlet configured to be in fluid communication with the respiratory system;
an actuator disposed within the valve body in a flow path between the inlet and the outlet,
Wherein the actuator is biased towards the inlet, the actuator being moved away from the inlet when the pressure exceeds a selected pressure level, the movement adjusting a flow path between the inlet and the outlet to regulate a gas pressure in the respiratory system to be within a predetermined PEEP pressure range, wherein the selected pressure level is within the predetermined PEEP pressure range.
8. A valve as claimed in any one of the preceding claims, wherein the valve comprises a biasing member operatively coupled to the actuator.
9. The valve of claim 8, wherein the actuator is biased toward the inlet by the biasing member.
10. A valve as claimed in claim 8 or 9, wherein the biasing member applies a variable resistance to the actuator during movement of the actuator.
11. The valve of claim 10, wherein the variable resistance applied by the biasing member counteracts a force applied to the actuator caused by the gas pressure at the inlet.
12. A valve as claimed in any one of the preceding claims, wherein the flow path between the inlet and outlet of the valve is closed when the pressure at the inlet is below the selected pressure level.
13. The valve of claim 12, wherein when the pressure at the inlet is above the selected pressure level, the pressure overcomes a variable resistance applied to the actuator by the biasing member and opens a flow path between the inlet and outlet of the valve.
14. A valve as claimed in any one of claims 8 to 13, wherein the biasing member biases the actuator against a portion of the valve body when the flow path is closed.
15. The valve of claim 14, wherein the portion of the valve body forms a valve seat for the actuator.
16. The valve of claim 15, wherein a flow path between an inlet and an outlet of the valve is open when the actuator is displaced from the valve seat.
17. The valve of claim 16, wherein the flow path is determined at least in part by a relative displacement of the actuator from the valve seat.
18. The valve of claim 17, wherein the flow path increases in size as the actuator is displaced farther away from the valve seat.
19. A valve as claimed in claim 17 or 18, wherein the flow path decreases in size as the actuator returns to the valve seat.
20. A valve as claimed in any one of the preceding claims, wherein the valve comprises a support member for the actuator for guiding and stabilizing movement of the actuator.
21. A valve as claimed in claim 20, wherein the support member is an elongate shaft along which the actuator is arranged to slide during movement thereof.
22. The valve of claim 21, wherein the actuator includes an aperture for receiving the shaft therein.
23. The valve of claim 22, wherein the cross-section of the shaft and the orifice are configured to have substantially similar shapes and/or sizes.
24. The valve of claim 22, wherein the orifice has a generally square shape and the shaft has a circular cross-section.
25. A valve as claimed in any one of claims 22 to 24, wherein the orifice has a diameter of substantially 1 to 5mm.
26. A valve as claimed in any one of the preceding claims, wherein the actuator comprises a substantially planar lower surface or the actuator comprises a circular disc, wherein the circular disc comprises a substantially planar lower surface.
27. The valve of claim 26, wherein the circular disk has a size or area closely matching the size of the valve inlet.
28. A valve as claimed in any one of the preceding claims, wherein the area of the actuator is greater than the cross-sectional area of the inlet, preferably the difference in area of the actuator and the inlet of the valve body is in the range 0 to 80mm 2 or 1 to 20mm 2.
29. A valve as claimed in any one of claims 8 to 28, wherein the actuator comprises a portion for engaging the biasing member.
30. A valve as claimed in any one of the preceding claims, wherein the valve body comprises a housing and an outlet member.
31. The valve of claim 30, wherein the outlet member is arranged to be coupled to an end of the housing.
32. A valve as claimed in claim 30 or 31, wherein the housing comprises a hollow cylindrical shape and the valve seat is formed on an inner wall of the housing.
33. A valve as claimed in any one of claims 30 to 32, wherein the outlet member comprises at least one outlet member orifice to vent gas received at the inlet of the valve to ambient air.
34. The valve of claim 33, wherein the outlet member orifice has a minimum area of approximately 20mm 2.
35. The valve of any of the preceding claims, wherein the outlet of the valve is arranged to be blocked when PIP is delivered to the patient.
36. Valve according to any of the preceding claims, wherein the outlet of the valve is arranged to be blocked by the finger or digit of an operator during PIP delivery.
37. A valve according to any one of the preceding claims, wherein the outlet of the valve is not blocked when PEEP is delivered to the patient.
38. A valve as claimed in any one of claims 22 to 37, wherein the shaft is received by an aperture of the actuator at a first end and is connected to a portion of the valve body at a second end.
39. A valve as claimed in any one of claims 8 to 38, wherein the biasing member is a spring, coil spring or conical coil spring.
40. A valve as defined in any one of claims 8 to 39, wherein the biasing member is maintained in a compressed state when the actuator is biased towards the valve seat and is further compressed when the actuator is lifted away from the valve seat.
41. The valve of claim 10, wherein the variable resistance applied to the actuator by the biasing member is dependent at least in part on: the spring constant, compression, and/or displacement of the actuator from the valve seat.
42. The valve of claim 40, wherein the variable resistance applied by the biasing member to the actuator is calculated as F Bias of = k (x_initial compression + x_lift), wherein:
K=the spring constant of the spring;
X_initial compression = initial compressed length of the spring when the flow path is closed (i.e., the difference between the original uncompressed length of the spring and the length of the spring after initial compression and placement within the valve body);
x_lift = displacement of the actuator from the valve seat under pressure P.
43. The valve of claim 10, 41 or 42, wherein the gas pressure at the inlet applies a lifting force (F Lifting up ) to the actuator in a direction opposite to the variable resistance applied to the actuator by the biasing member.
44. The valve of claim 43, wherein the lifting force is calculated according to F Lifting up ＝P*A actuator with a spring , wherein:
p=gas pressure at the valve inlet;
A actuator with a spring = area of the actuator exposed to gas pressure at the valve inlet.
45. The valve of claim 44, wherein the position of the actuator is determined by the relative relationship of F Bias of and F Lifting up .
46. The valve of claim 45, wherein the actuator is displaced from the valve seat when F Lifting up is greater than F Bias of .
47. The valve of claim 45 or 46, wherein the actuator begins to return to the valve seat when F Lifting up is less than F Bias of .
48. The valve of claim 41, wherein the spring constant is determined at least in part by one or more of: spring wire diameter, diameter of spring coils, number of spring coils, spring pitch, and material.
49. A valve as defined in claim 48, wherein the spring constant is less than 0.05N/mm.
50. A valve as defined in claim 48, wherein the spring constant is between 0.005 and 0.02N/mm.
51. The valve of claim 30, wherein the outlet member is configured to adjust compression of the biasing member by adjusting a distance of the outlet member relative to the actuator.
52. The valve of claim 51, wherein compression of the biasing member is adjusted by twisting the outlet member in a first or second direction, wherein the outlet member moves closer to the actuator and further compresses the biasing member when the outlet member is twisted in the first direction and moves farther from the actuator and reduces compression of the biasing member when the outlet member is twisted in the second direction.
53. The valve of claim 52, wherein twisting of the outlet member will adjust a predetermined pressure range in which the valve is configured to adjust.
54. The valve of any of the preceding claims, wherein the pressure of the gas within the respiratory system is determined at least in part by an unexpected leak resulting in the pressure being below or above a target PEEP pressure to be delivered to the patient and/or a flow change caused by patient respiration.
55. A valve as claimed in any one of the preceding claims, wherein the valve is arranged to compensate for pressure variations caused by accidental leakage by reducing the size of a gas flow path through the valve.
56. A valve as claimed in any one of the preceding claims, wherein the valve is arranged to compensate for pressure variations caused by patient breathing by allowing a variable portion of gas within the respiratory system to flow through the valve and out of the respiratory system.
57. The valve of any of the preceding claims, wherein the respiratory system is configured to deliver breathable gas to a patient at a flow rate of 5-15L/min when delivering respiratory therapy.
58. A valve according to any one of the preceding claims, wherein the predetermined pressure range is between 5 and 15cm H 2 O when PEEP is delivered.
59. The valve of any of the preceding claims, wherein the selected pressure level is in the range of 6 to 10H 2 O, or 3 to 7cm H 2 O, or 4 to 6cm H 2 O, or 4.5-5.5cm H 2 O.
60. The valve of claim 59, wherein movement of the actuator is capable of regulating the pressure of breathable gas within the respiratory system to vary from-2 to +2cm H 2 O, or-1 to +1cm H 2 O, or-0.5 to +0.5 cm H 2 O.
61. The valve of any one of the preceding claims, wherein the valve is configured to be removably attached to a ventilation orifice of the respiratory system.
62. The valve of claim 61, wherein the vent orifice is provided in a tee device.
63. The valve of claim 61, wherein the ventilation aperture is disposed in an exhalation tube of a CPAP device.
64. A valve as claimed in any one of the preceding claims, wherein the valve comprises an adapter to allow the valve to be detachably coupled to the respiratory system.
65. A valve as claimed in any one of the preceding claims, wherein the valve is configured to be detachably coupled to a tee arrangement.
66. A valve as claimed in any one of the preceding claims configured to be detachably coupled to an exhalation tube of a CPAP device.
67. A device for facilitating regulation of pressure of a gas supplied to a patient, the device comprising:
A housing defining a chamber, the housing having an inlet configured to connect with a source of a gas flow providing a flow of gas to the chamber, an outlet configured to direct gas out of the chamber, and a vent comprising an actuator for controlling the discharge of gas from the chamber through the vent;
A biasing member biasing the valve member toward the seating position;
Wherein the vent and the actuator are mutually adapted such that the actuator has an exposed area exposed to the gas in the chamber, wherein the biasing member has a spring constant selected relative to the exposed area of the actuator, wherein the actuator is maintained in a seating position until the pressure of the gas in the chamber exceeds a selected pressure level.
68. A pressure regulating device for facilitating regulation of pressure of a gas supplied to a patient, the device comprising:
a housing defining a chamber, the housing including an inlet couplable to a flow source providing a flow of gas to the chamber, an outlet couplable to a patient interface for supplying gas from the chamber to the patient, and a vent including an actuator for controlling the discharge of gas from the chamber through the vent;
A biasing member biasing the actuator toward a seating position, wherein the actuator is maintained in the seating position until a pressure of the gas in the chamber exceeds a selected pressure level; and
An outlet member associated with the vent, the outlet member including a support member aligned with the vent axis, the actuator having an aperture formed therein, the aperture receiving the support member such that the actuator moves along the support member when moved relative to the seating position.
CN202280063942.7A 2021-09-21 2022-09-21 Valve Pending CN118076400A (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US63/261,439 2021-09-21
US202263366660P 2022-06-20 2022-06-20
US63/366,660 2022-06-20
PCT/IB2022/058897 WO2023047286A1 (en) 2021-09-21 2022-09-21 Valve

Publications (1)

Publication Number Publication Date
CN118076400A true CN118076400A (en) 2024-05-24

Family

ID=91095782

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202280063942.7A Pending CN118076400A (en) 2021-09-21 2022-09-21 Valve

Country Status (1)

Country Link
CN (1) CN118076400A (en)

Similar Documents

Publication Publication Date Title
JP7334210B2 (en) respiratory aid
AU2021203341B2 (en) Pressurizing masks, systems and methods
US9038634B2 (en) Ventilation mask with integrated piloted exhalation valve
US9415183B2 (en) Ventilation mask with integrated piloted exhalation valve
EP2266651B1 (en) Breathing assistance apparatus
JP2011519655A (en) Exhaust assembly
WO2014164813A1 (en) Ventilation mask with integrated piloted exhalation valve
WO2014025591A1 (en) Ventilation mask with integrated piloted exhalation valve
CN118076400A (en) Valve
WO2023047286A1 (en) Valve

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication