Breathing system for substance inhalation

Abstract

The breathing system is arranged to cause a patient to continuously breathe and to inhale a substance during the breathing, the breathing system comprising: adding means for adding the substance to the gas to be inhaled, and control means for pressurizing the contained gas. The adding device comprises: a container for accommodating a substance in a liquid form; and a vaporizing device for vaporizing the substance. The contained gas communicates to the substance in the container to drive the substance to the vaporization device. The control device comprises a decompression device for causing the pressurized gas to lose at a speed less than the speed at which the control device can pressurize the gas. Alternatively or additionally, a flow control device (122) is arranged to limit the flow of the substance between the substance container and the vaporization device.

Description

Technical Field

[0001] The present invention relates to a breathing system for a patient to inhale substances, in particular analgesic, anesthetic and / or sedative substances. The invention also relates to a method of using such a device. Background Art

[0002] The inventors have noticed a lack of a breathing system that enables a patient to inhale an anesthetic, analgesic and / or sedative substance in which the patient can intervene or control the amount of the anesthetic, analgesic and / or sedative substance administered so as to remain comfortable without intervention by a medical professional. Safety is a significant issue in such systems in order to avoid the risk of overdose. In addition, conventional pumps for reliably adding small amounts of substances between 10 microliters and 150 microliters to the inhaled gas can be expensive. The object of the present invention is to address these problems in whole or in part. Summary of the invention

[0003] According to a first aspect of the invention, there is provided a breathing system for a patient to breathe continuously and to inhale a substance during breathing, the breathing system comprising: an adding device for adding a substance to a gas to be inhaled, the adding device comprising a container for containing the substance in liquid form and a vaporizing device for vaporizing the substance; and a control device for pressurizing the contained gas, wherein the contained gas is connected to the substance in the container to drive the substance to the vaporizing device, the control device comprising a decompression device that causes the pressurized gas to be lost at a rate less than the rate at which the control device can pressurize the gas. Thus, the decompression device causes the amount of the substance added to the gas to be inhaled to decrease over time until no more substance is added.

[0004] The control device may also include a flow control device arranged to enable the substance to flow between the container and the vaporization device and to restrict the flow of the substance to the vaporization device, wherein the contained gas is communicated to the substance in the container to drive the substance through the flow control device to the vaporization device.

[0005] According to a second aspect of the present invention, there is provided a breathing system for a patient to breathe continuously and inhale a substance during breathing, the breathing system comprising: an adding device for adding a substance to a gas to be inhaled, the adding device comprising a container for containing the substance in liquid or gaseous form and a vaporizing device for vaporizing the substance; and a control device for pressurizing the contained gas, wherein the contained gas is connected to the substance in the container to drive the substance to the vaporizing device, the control device comprising a flow control device arranged to cause the substance to flow between the container and the vaporizing device and to restrict the flow.

[0006] The flow control device may be located in a tube between the container and the vaporizing device, or at one end of the tube through which the substance flows.

[0007] The control device may further include a pressure reducing device for causing the pressurized gas to be lost at a rate slower than the rate at which the pressurizing device pressurizes the gas.

[0008] The following features are alternative features and / or preferred features in the first aspect and / or the second aspect.

[0009] The pressure reducing device may include a speed control portion for adjusting the speed. For example, the pressure reducing device may be a needle valve capable of achieving such control.

[0010] The control device may include user controls that can be operated by the patient to provide input to the control device for further operation by the patient. The user controls may be operated by the patient through consciously performed actions (e.g., finger or hand, blink or bite actions).

[0011] The pressure reducing device may be coupled to the control device, and the control device may be configured to regulate a rate of loss of pressurized gas based at least on the input.

[0012] The control means may be configured to control pressurisation of the contained gas based at least on the input.

[0013] The input can be pneumatic, mechanical or electrical.

[0014] The user controls may be positioned separately from the patient's airway interface, such as being held or worn by the patient's hand, when the breathing system is in use. One or more other components of the control device or the entire control device may be positioned separately from the patient's airway interface when the breathing system is in use. In addition, the container may be positioned separately from the vaporizer and connected to the vaporizer via a conduit to provide the vaporizer with a substance. The container may be provided together with the user controls as part of a handheld device.

[0015] The user control may be operated by the patient when in a first state (e.g., an expanded state when the input is pneumatic), and the patient's operation moves the user control to a second state (e.g., a contracted state when the input is pneumatic). In this case, the control device may include a reset limiter configured to set a time period for the user control to return to the first state from the second state.

[0016] The user control may be biased toward a first state and may include means for biasing toward the first state.

[0017] The operation of the user control to move the user control from the first state to the second state can remove the air in the chamber within the user control. In this case, the reset limiter allows air to enter the chamber at a speed that makes the user control return to the first state at the end of the time period.

[0018] The control device may include an expandable member, and the gas is filled into the expandable member through the operation of the user control, thereby expanding the expandable member. The expandable member is biased towards a contracted state. In this case, the expandable member can act on the substance to drive the substance to the vaporization device.

[0019] Alternatively, the control device may further include a pressurizing device (e.g., an air compressor) for pressurizing the gas and a controller coupled to the pressurizing device, the controller being used to control the pressurizing device to control the pressurization of the gas. For example, the controller may provide control instructions to the pressurizing device. The user controller and the controller may be electrically connected, and the input received by the control portion is electrical.

[0020] The contained gas can be communicated to the substance in the container via the intermediate member, and the contained gas pushes the intermediate member against the substance to drive the substance to the vaporization device. The intermediate member may include an elastically deformable membrane that separates the gas and the substance. The membrane may be an expansion membrane that is sealedly attached to the container around the opening of the container, the expansion membrane connects the container and the gas supply, and the expansion membrane is arranged so that when the gas pressure in the expansion membrane increases, the expandable member expands into the substance.

[0021] The breathing system may also include a patient airway interface that may be placed on the patient so that inhalation and exhalation occur repeatedly and continuously through the patient airway interface.

[0022] The patient airway interface can be placed on the patient and remain in place indefinitely without requiring the patient to use his hands. For example, the patient airway interface can be placed on the patient by a band around the patient's head.

[0023] When the breathing system is used, the vaporizing device or the additive unit may be fixedly mounted on the patient's airway interface. The additive device may not be carried by any other component except the patient's airway interface.

[0024] Controls other than the user controls may be fixedly mounted on the patient airway interface.

[0025] The substance may be an analgesic, anesthetic and / or sedative substance.

[0026] The components required to manufacture the breathing system can be obtained and assembled at a reasonable cost. Although not required, the breathing system can be disposable. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Embodiments of the present invention are described hereinafter, by way of example only, with reference to the accompanying drawings, in which: Figure 1A Schematically illustrating components according to an embodiment of the present invention; Figure 1Bis a block diagram of components of an adding unit and a control device according to an embodiment; Figure 2A is a schematic diagram of components of an adding unit according to another embodiment; Figure 2B yes Figure 2A A schematic diagram of components of the present invention, and also includes a housing; Figure 3 yes Figure 2A Schematic diagram of components of and also including a coupled expandable member according to a modified embodiment; Figure 4 schematically illustrates components of a breathing system according to another embodiment; Figure 5 schematically illustrates components of a breathing system according to yet another embodiment; Figure 6 Schematically shows a breathing system according to another embodiment Figure 2A and Figure 2B The components of the embodiment are similar to the components, but have a single control portion for operating both components; Figure 7 is an exemplary cross-sectional view of a patient mask for use in an embodiment; Fig. 8A is a schematic diagram of an embodiment including an intermediate member between contained gases and substances; Figure 8B is a schematic diagram of an embodiment including a modified intermediate member; Figure 8C is a schematic diagram of an embodiment of a further modified intermediate member in the form of a piston. DETAILED DESCRIPTION

[0028] Embodiments of the present invention relate to breathing systems for controllably adding a substance to an inspired gas.In this document, reference to an "operator" is to be understood as reference to a patient or other person such as a medical professional.

[0029] refer to Figure 1A , a breathing system according to these embodiments includes a housing 100 having a flow control valve, a patient airway interface (PAI) 102, an addition unit 104, and a control device 106. The control device 106 includes a user control 108 and a pressure relief component 110. In some embodiments, the control device 106 includes one or more sensors. The control device includes a pressure generating function to provide pressure to drive the addition of a substance. Also refer to Figure 1B, the adding unit 104 comprises a substance reservoir 112, a first conduit 115, a gas container 116, a vaporising unit 118, a second conduit 120 and a flow control device in the form of a flow restrictor 122. The control device comprises a pump unit 119, which is shown in dashed lines to indicate that the pump unit 119 may not be present in some embodiments, and the control device comprises a pressure generating function in the control unit 107, and the control device also comprises a user controller 108 in some of these embodiments.

[0030] The housing 100 provides a structure for mounting the PAI 102, the adding unit 104, and the control unit 107. The PAI 102 is initially disconnected from the housing 100 and can be connected to the housing 100 for use. The snap-fit ​​system on the PAI 102 and the housing 100 is not shown in the drawings, but the position of the snap-fit ​​system indicated by 125 is provided. Alternatively, the PAI 102 and the housing 100 can be connected using corresponding threads at the same position. The embodiment is not limited to any specific connection mode of the PAI 102 and the housing 100. The initial disconnection enables the selection of PAIs of different shapes / sizes for different patients, and the disposal of the PAI 102 after use and the reuse of the rest of the respiratory system. Alternatively, the PAI 102 and the housing 100 can be provided as a single component, i.e., permanently connected.

[0031] In the case where the PAI 102 and the housing 10 are connected, they are fixedly arranged relative to each other. The adding unit 104 and the control device 106 are mounted on the housing 100 and fixed relative to the housing 100. In a variant embodiment, these components can be flexibly attached. In some variant embodiments, one or more components of the adding unit 104 (e.g., a substance container and / or a gas container 116) and / or one or more components of the control device 106 (e.g., a user controller 108) or all of the control device 106 may not be mounted on the housing 100, and instead, may be connected to other components mounted on the housing 100, for example, via a flexible cable. In particular, as described below, the user controller 108 may be physically separated from the rest of the control device 107, and may be, for example, handheld and connected to another part of the control device with such a cable. In some embodiments, the control device may be provided as a handheld device that can be operated by a patient. Such a device may also include a substance container 112 and / or a gas container 116, in which case a second conduit extends between the handheld device and the vaporization unit 118.

[0032] The flow control valve includes a first one-way inhalation valve 118 and a second one-way inhalation valve 112 and a one-way exhalation valve 114. The first inhalation valve 118 is located at the air inlet 111 of the breathing system and prevents the gas with the substance from escaping into the environment through the air inlet 111. The second inhalation valve 112 is positioned to prevent the exhaled gas from entering the vaporization unit 118. In some embodiments, the second inhalation valve 112 is optional and can be omitted. The exhalation valve 114 is configured to enable the exhaled gas to be discharged from the breathing system and prevent air from entering from the environment. The arrows present in FIG. 1 indicate the airflow through the breathing system. A filter (not shown) such as an activated carbon filter can be positioned together with the exhalation valve 114 to remove any residual substances in the gas flowing out of the PAI 102.

[0033] Also refer to Figure 1B , the substance container 112 contains a substance 113 in liquid form and a gas above the surface of the substance. The gas container 116 also contains a gas. The gas is air, although one or more other gases may be used in addition or alternatively in variant embodiments. The substance container 112 is operably connected to the gas container 116 via a first conduit 115. The pressure of the substance in the substance container 112 is equal to the pressure of the gas in the gas container 116. When the breathing system is used, the substance container 112 is oriented so that the outlet of the conduit 115 into the substance container 112 is located above the surface of the substance 113. The control device is operably connected to the gas container 116 so as to increase the pressure of the gas contained in the gas container 116.

[0034] The material container 112 is connected to the vaporization unit 118 through the second conduit 120 and the flow controller 122. The material flowing from the material container 112 to the vaporization unit 118 flows through the second conduit 120 and the flow controller 122. The pressurized gas acts on the material to drive the material through the second conduit 120 and the flow controller 122. The flow controller 122 is arranged to limit the flow rate of the material flowing out of the container 112. For example, the flow rate can be limited to less than 10 microliters per second, or less than 5 microliters per second, or less than 2 microliters per second by the flow controller 122 when in use. The flow rate may depend on the pressure difference across the flow controller, but the device can be configured so that the flow rate does not exceed these limits.

[0035] The flow controller 122 can be a hollow tube in the form of a needle, for example. Alternatively, the flow controller can provide a labyrinthine flow channel. Alternatively, the flow controller can include an area of ​​compressed or woven material such as a wick or compressed fabric. In variant embodiments, the flow controller 122 should not be limited thereto, and can alternatively provide a function of obstructing the free flow of the substance 113 to the vaporization unit 118, so that a driving pressure is required to produce a clinically significant substance flow.

[0036] In a variant embodiment where the gas container 116 is adjacent to the substance container 116, the first conduit 115 may be in the form of an opening between the gas container 116 and the substance container 112. In addition, in a variant embodiment where the substance container 112 is adjacent to the vaporization unit 118, the second conduit 120 may simply consist of a flow restrictor 122 and openings to the substance container 112 and the vaporization unit 118.

[0037] The control device includes a control unit 107 and a user controller 108. The user controller 108 is operable to provide input to the control unit 107 in response to the operator's operation of the user controller 108. The user controller 108 is operable, for example, in manual operation. Although the user controller 108 can be mounted on the housing 100, in a preferred embodiment, the user controller 108 is connected to other control components of the control unit 107 by a flexible cable, so that the user controller 108 can be placed or held in the patient's hand for manual operation, i.e., handheld and / or wearable. In a variant embodiment, the user controller 108 is operable in any physical action (e.g., a biting action or a blinking action) performed by the patient's conscious control. Alternatively, the user controller 108 can be configured to be operated by an operator other than the patient.

[0038] In some embodiments, the control unit 107 includes a microcontroller, and the pressure generating function includes a pump unit 119. In this case, the microcontroller is coupled to the user control 108, and the user control 108 is configured to provide an electrical signal to the microcontroller in response to the patient's operation. The microcontroller may also be coupled to one or more sensors to receive data from the one or more sensors. The microcontroller is also coupled to the pump unit 119 to control the pressurization of the gas in the gas container 116 by the addition unit.

[0039] The microcontroller comprises a processor and a memory. Computer program code executable by the processor is stored on the memory for determining control instructions for the pump unit 119 based on the received input, and in the case of one or more sensors, real-time data from the one or more sensors is also stored on the memory. In variant embodiments, the control unit 107 may be provided with dedicated hardware or a mixture of dedicated hardware and software in order to perform the determination. In other embodiments, the control device may not include a microcontroller and may be mechanical and / or pneumatic in nature, i.e., having only mechanical and / or pneumatic control components.

[0040] The pressure reducing component 110 allows gas to leak from the gas container 116 into the environment at a speed that is less than the speed at which the pump unit 119 can add gas. For example, the pump unit 119 can pressurize the gas in the gas container in less than one second, and the loss of pressure in the gas container 116 that the pressure reducing component 110 may cause is sufficient to make the time for adding substances to the inhaled gas greater than 2 seconds but less than 60 seconds or less than 30 seconds or less than 15 seconds or less than 10 seconds. Therefore, the pressure reducing component 110 is configured to gradually reduce the pressure of the gas when the pump unit 119 is not operating to increase the pressure of the gas. The pressure reducing component 110 can be configured to allow the contained gas to escape into the environment until the remaining contained gas reaches the ambient pressure. Alternatively, the pressure reducing component 110 is configured to allow the pressure in the container 112 to be reduced until the pressure has been reduced to a predetermined pressure that is lower than the pressure required for the substance to flow through the flow controller 122 but higher than the ambient pressure. The pressure reducing component 110 can be in the form of a valve in the wall of the gas container 116 that connects the inside of the gas container 116 to the outside, and can be referred to as a "leak valve".

[0041] The pressure relief component 110 may be configured to allow gas to escape from the gas container 116 at a fixed rate. In a variant embodiment, the rate may depend on the pressure within the gas container 116. In another variant embodiment, the rate may be set by the operator; for example, the control device 106 may include a rate control that enables this. In some embodiments, the rate may depend on input caused by the patient operating the user control 108. In such an embodiment, where the control unit 106 includes a microcontroller, the pressure relief component 110 may be operably connected to the microcontroller, and the microcontroller may be configured to dynamically control the rate using a predetermined algorithm of code that changes the rate based on input from the operation of the user control 108. In other variant embodiments, where the control device also includes such a microcontroller, such a predetermined algorithm may cause a change in rate based on real-time information received additionally or alternatively from one or more sensors. The higher the rate, the faster the addition of the substance to the inhaled gas ends without further pressurization by the pump unit 119.

[0042] In a variant embodiment, the pressure reduction component 110 is located in the first conduit 115 instead of in the gas container 116. In another variant embodiment, the pressure reduction component 110 is located in the substance container 112 above the surface of the substance. In this case, the pressure reduction component 110 is positioned so that when the breathing system is in use, the pressure reduction component 110 is arranged so that the gas exerts pressure on it instead of the substance exerting pressure on it, that is, it is located above the surface of the substance 113.

[0043] PAI 102 is shown in the form of a mask. In a variant embodiment, mask 10 can be replaced by another type of PAI. PAI can be, for example, a nose clip, a nasal mask, or an invasive device such as a supraglottic airway. Such a nasal mask can be, for example, particularly suitable for use in the dental field. Patients can be prevented from breathing through their mouths by means known in the art. Embodiments of the present invention are not limited to any particular form of PAI 102, which serves as a conduit for all inhaled and exhaled respiratory gases and requires the patient to repeatedly and continuously inhale and exhale through the respiratory system. For example, in many applications, the PAI can be placed on the patient so that inhalation and exhalation are performed only through the respiratory system for at least 10 minutes. For many applications, the PAI can be placed in this way for at least 30 minutes.

[0044] The vaporization unit 118 includes a material 123 onto which the substance is dispersed after it exits the flow controller 122. The vaporization unit can be composed entirely of the material 123. The material 123 is attached across the interior of the PAI 102, attached to the PAI 102 at the edge, so that the carrier gas must pass through the PAI 102. The second conduit 120 extends into the PAI 102 to be dispersed on the material 123. If the housing 100 and the PAI 102 are initially separate, it may be necessary to insert the second conduit 120 through a hole in the PAI 102. In alternative embodiments, the material may instead be attached across the interior of the housing 100 or include a portion of the housing 100, in which case the location of the material is indicated by the dotted line 123a. In some embodiments, the vaporization unit 118 may include a grid mounted on the housing 100 for the material 123 to be positioned against, or two grids for the material 123 to be sandwiched between.

[0045] The material 123 is preferably configured to diffuse the substance, for example, by capillary action to increase the surface area of ​​the substance and thereby promote vaporization into the air of flow. The material is preferably hygroscopic, although the embodiment is not limited to this. The material 123 is arranged vertically across the flow path relative to the carrier gas. The carrier gas needs to pass through the material 123 that presents low inhalation resistance. In a variant embodiment, the material 123 can only partially span the housing 100 instead of completely spanning, or extend longitudinally relative to the air flow direction so that the carrier air passes above it. The embodiment should not be limited to whether the material 123 is located in any specific setting in the housing 100 or PAI 102. The material 123 can be, for example, in the form of a piece of gauze or a fabric (e.g., cotton) pad. The embodiment is not limited to any specific form.

[0046] The vaporization unit 118 is configured to diffuse the substance so that the substance is vaporized quickly due to the speed at which the substance flows toward the vaporization unit 118. This avoids the substance from being retained on the material 123 for an excessively long time (e.g., more than 10 seconds) due to the patient's breathing rate. In addition, the vaporization unit 118 is configured to promote rapid vaporization to avoid any accumulation of the substance in the housing 100.

[0047] In use, the breathing system enables the patient to breathe through it, and usually also applies substances according to the input of the operator. First, the PAI 201 is worn on the patient so that the patient is forced to breathe through the breathing system and perform repeated and continuous inhalation and exhalation. The operator may need to open the breathing system. Then, when more substances need to be applied, the patient operates (or attempts to operate in some embodiments below) the user control 108. The control device determines whether the gas in the gas container 116 is to be pressurized, thereby causing more substances to be added to the inhaled air, and if so, the gas container 116 is pressurized accordingly. In the case where the control device includes a control unit 107 including a microcontroller and a pump unit 119, this includes the microcontroller making a determination and therefore providing a control instruction to the pump unit 119, and the pump unit 119 is used to increase the pressure in the gas container 116. In the case where the control device is only pneumatic and / or mechanical, this determination depends on the state of the control device.

[0048] The embodiments described below can be considered as possible implementations of the many general embodiments described above. The same or functionally similar parts in different embodiments are represented by the same reference numerals in the corresponding one or more figures showing the corresponding embodiments and the reference numerals of the corresponding figures are increased by 100.

[0049] refer to Figure 2A According to an embodiment, the control means is mechanical and pneumatic. The control means comprises a control unit 207 and a user control 208. These components are operable to provide gas to the substance container 112 described above to drive the substance to the vaporization unit 118.

[0050] The control unit 207 includes a first one-way valve 230 and a second one-way valve 231, a pressure reducing member in the form of an adjustable first needle valve 232, a recovery time control unit in the form of an adjustable second needle valve 233, and a tube. The first needle valve 232 includes a first knob 234 for controlling the flow rate through the first needle valve 232. The second needle valve 233 includes a second knob 235 for controlling the flow rate through the second needle valve 233.

[0051] A first needle valve 232 is coupled to the gas container 216 to allow the contained gas to gradually escape. The first needle valve 232 can be operated by a first knob 234 to adjust the escape rate of the contained gas, which also depends on the pressure of the gas.

[0052] The user control 208 is in the form of a pump 236 that is preferably held by the patient. The cable 222 is a tube that is sealingly connected to the pump 236. The pump 236 has an internal chamber and can be squeezed in a manual squeezing action to provide input to the control unit 207 in the form of pumped air. The pump 236 is biased toward the expanded state; for example, the pump 236 can be made of a suitable elastic rubber that is inherently configured to move to the expanded state. Alternatively, the pump 236 can be formed by a bellows or similar device and biased toward the expanded state by an elastic member such as a spring.

[0053] The cable 222 is connected at one end thereof to the first tube 237 through the first connector 241, and the first tube 237 is in turn connected at the other end thereof to the second one-way valve 231. The second tube 238 connects the second one-way valve 231 to the gas container 216. The second one-way valve 231 allows air to flow from the pump 236 to the gas container 216, i.e., from the first tube 237 to the second tube 238, and prevents flow in the reverse direction.

[0054] The second needle valve 233 is connected to the first tube 237 via a third tube 239. The second needle valve 233 is also connected to the first non-return valve 230 via a fourth tube 240. The first non-return valve 230 allows ambient air to flow into the second needle valve 233 and prevents air from flowing in the opposite direction. Therefore, the control unit 207 is arranged so that the pump 236 must draw air through the second needle valve 233 in order for the pump 236 to expand from a compressed state to an expanded state. Therefore, the recovery time control limits the speed at which the patient can cause the pump to supply air to the control unit 207, thereby setting a maximum speed at which the amount of substance that can be administered to the patient.

[0055] The first needle valve 232 is connected to the second tube 238 through the fifth tube 242. Air can flow from the gas container 216 to the environment through the second needle valve 232.

[0056] In addition, reference Figure 2B , the components are mounted on the housing 200. Bolts 243 hold the parts of the housing 200 in place.

[0057] In use, the patient operates the user control 208, i.e., squeezes the pump 236. This forces air through the cable 222, through the second one-way valve 231, thereby pressurizing the gas container 216. The pressurized gas acts to drive the substance toward the flow controller 122. As the substance is so driven, air is exhausted from the control unit 207 through the first needle valve 232, thereby reducing the pressure in the gas container 216. In addition, because the pump 236 is biased toward the expanded state, the pump 236 acts to allow air to enter through the second needle valve 233. The speed of returning to the expanded state depends on the speed at which the second needle valve 233 allows air to flow through it.

[0058] In a variant embodiment, the gas container 216 can be elastically expandable. For example, the gas container 216 can be formed of a deformable elastic material such as rubber or latex. Alternatively, the gas container 216 can be formed of an expandable flexible material and biased toward an initial volume. Operation of the user control can cause the expansion of the gas container 216.

[0059] refer to Figure 3 2 or its variant, except that the expandable member 343 is connected to the cable 222. In a variant embodiment, the expandable member 343 need not be connected to the cable 222, but can be connected to any position, and the interior of the expandable member 343 can be connected to the interior of the pump 236. For example, the expandable member 343 can be connected to the first tube 237 or the third tube 239, or directly connected to the pump 236 such as at its distal end. The expandable member 343 can be inflated to an expanded state and is biased towards a collapsed state. When the pump 236 is operated, the gas pressure in the cable 222 increases, and therefore the gas pressure in the expandable member 343 also increases, causing the expandable member 343 to expand. The presence of the expandable member 343 prevents a high pressure peak from occurring in the gas container 216 after the pump 236 is operated, and allows the pressure in the gas container 216 to remain higher than the pressure required to deliver the substance to the vaporization unit 118 for a longer period of time, thereby smoothing the pressure curve in the gas container 216. The expandable member 343 is made of, for example, rubber or latex that is inherently configured to move to a contracted state. Alternatively, the expandable member 343 can be formed by a bellows or similar device and biased to a contracted state by an elastic member such as a spring.

[0060] In use, these components function the same as those of Figure 2, except for the following: Air flows into the expandable member 343, causing expansion of the expandable member 343. The expandable member 343 acts to return to its collapsed state.

[0061] refer to Figure 4 In another embodiment, the pressure generating function in the form of a pump unit 419 includes an air inlet 445. The control unit 407 includes a microcontroller, and the one or more sensors include a pressure sensor 443 electrically coupled to the microcontroller via a cable 444. A user control 408, such as a button, can provide input in the form of an electrical signal to the microcontroller via a cable 422 in response to the user control being operated by an operator or patient.

[0062] The pressure sensor 443 provides data indicative of the real-time pressure in the gas container 416 to the microcontroller. The microcontroller is configured to control the pump unit 414 according to the pressure in the gas container 416 and according to operator-induced input from the user control 408 and its stored algorithms. The pump unit 414 may be in the form of a compressor.

[0063] The substance container 412 includes a container 448 having a threaded hole at its base 449. The container 448 is used in a direction where the opening is located at the bottom of the container. The container 412 includes a closure member 449 that is threadedly connected to the base 449, thereby sealingly closing the container 448. The closure member includes a first through hole for the first conduit 415 to extend through it in a sealed manner. The closure member 449 also includes a second through hole for one end of the second conduit 420 to be connected to it. One end of the first conduit 415 is located in the container 448 and terminates near the top of the interior of the container 448 so as to be located above the surface of the substance. The substance is prevented from being discharged from the container 448 by the flow controller 422 and the gas pressure in the gas container 416. When the gas pressure in the container 448 is greater than the gas pressure at one end of the second conduit 420 where the substance is provided to the vaporization unit, the flow controller 422 allows the substance to flow out of the container 448, in the illustrated embodiment, the substance is the material 446.

[0064] The control device comprises a leak valve 410 enabling the gas to gradually escape from the gas container 416. The leak valve 410 extends approximately from the midpoint of the gas container 416 to reduce the risk of matter reaching the leak valve and possibly blocking it.

[0065] The container 448 may be a vial obtained from a supplier with a substance therein and a seal not shown.

[0066] In use, the control unit 407 receives input from the user control 408 to further operate the user control by the patient. The control unit 407 determines whether to provide a control instruction to the pump unit 414 to add a substance to the gas to be inhaled. When the pump unit 414 is operated to increase the gas pressure, the substance flows to the vaporizing unit through the second conduit 420. The leak valve 410 limits the time when the gas container 416 is fully pressurized to drive the addition of the substance. The control unit 407 also receives real-time pressure data from the pressure sensor 416, so that the control unit 407 obtains feedback. Therefore, closed-loop control can be achieved.

[0067] refer to Figure 5In another embodiment, the control device includes a housing 550, a cable 522, a recess 551 in the housing 550, a button 552, a spring 553, a reset time control, a piston 555, and a cylinder 556 in the user control 508. The button 552 can be moved into the recess 551 (or chamber) into a depressed position (or state) by the patient overcoming the force of the spring 553 that causes the button 552 to enter the extended position. The piston 555 is slidably located in the cylinder 556. The piston 555 is attached to the button 552 so that pressing the button 552 into the recess 551 causes the piston 555 to move into the cylinder 556. The cable 522 is sealingly connected to the cylinder 556 at one end thereof and to the gas container at the other end. Therefore, pressing the button causes the air in the cylinder 556 to be pushed toward the gas container, thereby pressurizing the gas in the gas container 516.

[0068] The recovery time control includes a second needle valve 533 and a second adjustment knob 535, the second needle valve 533 being located between the recess 551 and the environment. The functions of these components are similar to the second needle valve 233 and the adjustment knob 235. The second needle valve 233 limits the speed at which ambient air enters the recess 551, thereby limiting the speed at which the button 552 returns to the extended position, thereby limiting the speed at which the patient provides air to the gas container 516.

[0069] The control device includes a leak valve 510 including a first needle valve having a needle 532 and a control portion 534. The leak valve 510 extends approximately from the midpoint of the gas container 516. Similar to the leak valve 410, the leak valve 510 limits the time that the gas container 416 is sufficiently pressurized to drive the addition of the substance.

[0070] refer to Figure 6 , relative to Figure 2A Simplified, relative to FIG. 2A to FIG. 2B In a variation of the described embodiment, flow through the first needle valve 632 and the second needle valve 633 may be controlled by a single control, such as a single knob 670. In this case, operation of the control results in both the air flow rate through the first needle valve 632 and the second needle valve 633 being reduced or both being increased.

[0071] refer to Figure 7 , the mask includes a substance container 712. A first conduit 715 extends from the mask to connect to a control device for pressurizing the gas. The mask includes a strap 771 for placing the mask on the patient's head. The material 723 is held in a mesh (not shown) that is joined to the interior of the mask at its edges.

[0072] The first conduit 715 leads to the container 712 near the uppermost portion of the container 712, which is defined based on the orientation of the container 712 when the mask is placed on the patient. The second conduit 720 leads to the container 712 near the lowermost portion of the container 712, which is defined based on the orientation of the container 712 when the mask is placed on the patient.

[0073] In a preferred embodiment of the present invention, when the breathing system is in use, the substance container is oriented so that the contained liquid is located at the bottom of the container under the action of gravity, whether the patient is in an upright or supine position. In some embodiments, the gas container may include a drain valve. Thus, if any substance accidentally enters the gas container, it will be discharged through the drain valve.

[0074] In the above embodiments, the pressurized gas acts directly on the surface of the liquid substance to drive the substance through the flow restrictor. In a variant embodiment, the gas can act on an intermediate member. This intermediate member also allows the substance to exist in gaseous or liquid form.

[0075] refer to Fig. 8A In one such embodiment, the intermediate member is in the form of a resiliently flexible and / or deformable membrane 890 located between the gas and the substance. The membrane 890 is attached (e.g., by an adhesive) around the inner wall of the container 812a to separate the gas and the substance. When the pressure of the gas pressurizes the gas due to the gas entering the container 812a through the first conduit 815a, it pushes the membrane 890 toward the substance, driving the substance through the second conduit 820. The embodiments are not limited to any particular orientation of the membrane 890. The membrane 890 can be made of, for example, rubber or latex.

[0076] refer to Figure 8B In another such embodiment, the intermediate member is in the form of an expansion bag 891 that is sealingly attached to the inside of the container 812b around the hole of the first conduit 815b entering the container 812b. When the gas pressure in the bag increases, the expansion bag 891 resists the expansion of the substance. The embodiments are not limited to any particular arrangement of the bag in the container 812b, although the bag is preferably at least partially immersed in the substance. The expansion bag 891 can be made of, for example, rubber or latex.

[0077] refer to Figure 8C In another such embodiment, the intermediate member is in the form of a piston 892, and the container 812c is at least partially a cylinder. The piston 892 can slide in the container. When the pressure of the gas increases, the gas pushes the piston 892 against the substance, thereby driving the substance toward the second conduit 820. For example, the piston 892 can be made of a hard plastic material. The piston 555 described above is an example of a similar intermediate member in another embodiment.

[0078] The substance is a volatile liquid. The substance may be an analgesic, anesthetic and / or sedative substance that has an analgesic, anesthetic and / or sedative effect on the patient. For example, the substance may be methoxyflurane, sevoflurane or ketamine. In variant embodiments, the substance may have alternative or additional effects.

[0079] The substance container of the embodiments may in all embodiments be in the form of a medical vial. In variant embodiments, alternative forms of containers may be provided that can be configured for replenishing substances.

[0080] In alternative embodiments, the vaporization unit 118 is not limited to this material. Alternative means for vaporizing the substance may be provided. In some embodiments, particularly where the substance to be used is highly volatile, the vaporization unit 118 does not need to diffuse the substance to facilitate vaporization. Instead, the vaporization unit 118 may simply be a space into which the substance is vaporized.

[0081] In an alternative embodiment, the vaporization device may include a heater for heating the substance. The heater may be located at the outlet of the second conduit 120. In this case, the substance need not be a volatile liquid, and may be any substance that can be vaporized by heating at a temperature that matches the performance of the heater. In the case of including a heater, the control device includes a microcontroller and a heater coupled to the microcontroller, and the microcontroller controls the operation of the heater by determining control instructions and providing control instructions to the heater. For example, the control instructions may include "on" and "off" instructions. The control instructions may also control the degree of heating. The control device may also include a temperature sensor for providing information indicating the temperature of the substance and / or the ambient temperature to the control device, and the control device may determine the control instructions regarding the degree of heating based on the information.

[0082] In an alternative embodiment, the vaporizing unit 118 may include a nozzle spray located at the outlet of the second conduit 120. In this case, the substance need not be a volatile liquid, but may be any liquid suitable for the nozzle spray to convert it into droplets and can be carried by the gas in the respiratory system and absorbed by the patient through inspiration.

[0083] Based on the embodiments described above, the manufacturing process for manufacturing the respiratory system will be obvious to those skilled in the art. For example, the mask can be made of hard plastic material or silicone, and the airway can be made of hard plastic material. The embodiments are not limited to the use of specific materials.

[0084] It will be apparent to those skilled in the art that various modifications may be made to the above described embodiments. In some embodiments, the gas container of the embodiments may be omitted. Instead, the space above or adjacent to the substance in the substance container may be used as a gas container.

[0085] When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. These terms should not be interpreted as excluding the presence of other features, steps or components.

[0086] Unless otherwise stated, all individual features and / or steps of all embodiments described herein are disclosed individually, and any combination of two or more such features is also disclosed. To the extent that, according to the common knowledge of ordinary technicians in the field, these features or steps or combinations of features and / or steps can be implemented as a whole based on the present specification, regardless of whether such features or steps or combinations of features and / or steps solve any problems disclosed herein.

Claims

1. A breathing system arranged to enable a patient to breathe continuously and to inhale a substance during breathing, said breathing system comprising: An adding device, used to add the substance to the gas to be inhaled, the adding device comprising: a container for containing said substance in liquid form; a vaporizing device for vaporizing the substance; Control means for pressurizing contained gas, wherein the contained gas is communicated to the substance in the container to drive the substance to the vaporizing means, the control means including pressure reducing means for causing the pressurized gas to be lost at a rate less than the rate at which the control means is capable of pressurizing the gas.

2. The breathing system according to claim 1, wherein: The control device also includes a flow control device arranged to enable the substance to flow between the container and the vaporization device and to restrict the substance from flowing to the vaporization device, wherein the contained gas is communicated to the substance in the container to drive the substance to the vaporization device.

3. A breathing system arranged to enable a patient to breathe continuously and to inhale a substance during breathing, said breathing system comprising: An adding device, used to add the substance to the gas to be inhaled, the adding device comprising: a container for containing said substance in liquid or gaseous form; a vaporizing device for vaporizing the substance; A control device for pressurizing a contained gas, wherein the contained gas is communicated to the substance in the container to push the substance from the container to the vaporizing device, the control device including a flow control device arranged to cause the substance to flow between the container and the vaporizing device and to restrict the flow.

4. The breathing system according to claim 3, wherein: The flow control device is located in a tube between the container and the vaporizing device or at one end of the tube through which the substance flows.

5. The breathing system according to claim 3 or 4, wherein: The control device also includes a pressure reducing device for causing the pressurized gas to be lost at a rate less than the rate at which the pressurizing device is able to pressurize the gas.

6. The breathing system according to any one of claims 1, 2 and 5, wherein: The pressure reducing device includes a speed control portion for adjusting the speed.

7. A breathing system according to any one of the preceding claims, wherein: The control device includes user controls operable by the patient to provide input to the control device for further operation by the patient.

8. A breathing system according to claim 7 when claim 7 is dependent on claim 6, wherein: The pressure reducing device is coupled to the control device, and wherein the control device is configured to adjust a rate of loss of pressurized gas based at least on input from the user control.

9. A breathing system according to any one of claims 7 and 8, wherein: The control device is configured to control pressurization of the contained gas based at least on the input.

10. A breathing system according to any one of claims 7 to 9, wherein: The input is pneumatic, mechanical or electrical.

11. A breathing system according to any one of claims 7 to 10, wherein: The user controls are for manual operation and are positioned spaced apart from the patient airway interface.

12. The breathing system of claim 11, wherein: When the breathing system is in use, the control device is positioned spaced apart from the patient airway interface.

13. The breathing system of claim 12, wherein: The container is positioned spaced apart from the vaporizing device and is connected to the vaporizing device by a conduit to provide the substance to the vaporizing device.

14. A breathing system according to any one of claims 7 to 13, wherein: The user control is operable by the patient when in a first state, and the patient's operation causes the user control to move to a second state, wherein the control device includes a reset limiter configured to set a time period for the user control to return from the second state to the first state.

15. The breathing system of claim 14, wherein: Operation of the user control to move the user control from the first state to the second state removes air from a chamber within the user control, wherein the reset limiter allows air to enter the chamber at a rate that causes the user control to return to the first state at the end of the time period.

16. The breathing system of claim 15, wherein: The pressurizing device comprises an expandable member through which a gas is disposed to expand the expandable member, wherein the expandable member acts on the substance to drive the substance at the flow control device.

17. A breathing system according to any one of claims 14 to 16, wherein: The user control is biased toward the first state.

18. A breathing system according to any one of the preceding claims, wherein: The contained gas is communicated to the substance in the container via an intermediate member, the contained gas pushing the intermediate member against the substance to drive the substance to the vaporizing device.

19. A breathing system according to any one of the preceding claims, further comprising: A patient airway interface is positionable on the patient so that inhalation and exhalation occur repeatedly and continuously through the patient airway interface.

20. The breathing system of claim 19, wherein: The patient airway interface is capable of being placed on the patient to remain in place indefinitely without the use of the patient's hands.

21. A breathing system according to claim 19 or 20, wherein: When the breathing system is in use, the additional unit is fixedly mounted on the patient airway interface.

22. A breathing system according to any one of claims 19 to 21, wherein: The control devices, except the user controls, are fixedly mounted on the patient airway interface when the breathing system is in use.

23. A breathing system according to any one of the preceding claims, wherein: The control device further includes a pressurizing device and a controller, wherein the pressurizing device is used to pressurize the gas, wherein the controller is connected to the pressurizing device to control the pressurizing device to pressurize the gas.

24. A breathing system according to any one of the preceding claims, wherein: The substance is an analgesic, anesthetic and / or sedative substance.

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