The present invention relates generally to an aerosol delivery device, such as a holding chamber, which is configured to provide indicia when the user has completed the inhalation of a predetermined volume, or completed the inhalation of a prescribed dosage of medicament, together with methods of delivering aerosol medicament and indicating the complete inhalation of the dosage of the medicament and methods of assembling the delivery device.
The use of an aerosol medication delivery apparatus and system to administer medication in aerosol form to a patient's lungs by inhalation (hereinafter “aerosol delivery system(s)”) is well known in the art. Such devices and systems include for example pressurized metered-dose inhalers (pMDIs), pMDI add-on devices, such as holding chambers, devices including a chamber housing and integrated actuator suited for a pMDI canister, nebulizers, dry powder inhalers and other such devices. While some aerosol delivery systems are configured to provide a visual indication to alert a caregiver when a patient is inhaling, such systems typically do not alert the user or caregiver that the user has inhaled all of their medication.
In one aspect, one embodiment of a medication delivery system includes a chamber housing defining an interior volume. The chamber housing has an inlet adapted to receive a dosage of medicament and an outlet spaced apart from the inlet. The inlet and outlet are in fluid communication with the interior volume. A flow channel is in fluid communication with the interior volume. A dosage indicator is translatable in the flow channel from a pre-inhalation position to a complete dosage position, wherein a positioning of the dosage indicator in the complete dosage position indicates a complete administration of the dosage of medicament through the outlet. In one embodiment, the dosage indicator is visible through the flow channel as the dosage indicator is translated between the pre-inhalation position and the complete dosage position.
In yet another aspect, a medication delivery system includes a chamber housing defining an interior volume and having an inlet adapted to receive a dosage of medicament and a user interface spaced apart from the inlet in a longitudinal direction. The inlet and user interface are in fluid communication with the interior volume. A flow channel is in fluid communication with the interior volume and extends in the longitudinal direction. A dosage indicator is translatable in the flow channel from a pre-inhalation position proximate the user interface to a complete dosage position proximate the inlet. A positioning of the dosage indicator in the complete dosage position indicates a complete administration of the dosage of medicament through the user interface. The dosage indicator includes a turbine that is rotatable in the flow channel as the dosage indicator is translated between the pre-inhalation position and the complete dosage position. In various embodiments, the dosage indicator is observable in the flow channel, for example the dosage indicator may be visible or audibly recognized as it moves in the flow channel and reaches the complete dosage position.
In another aspect, one embodiment of a medication delivery system includes a chamber housing defining an interior volume and having an inlet adapted to receive a dosage of medicament and a user interface spaced apart from the inlet in a longitudinal direction. The inlet and the user interface are in fluid communication with the interior volume. A flow channel is in fluid communication with the interior volume and extends in the longitudinal direction. A rod is disposed in the flow channel. A dosage indicator is translatable in the flow channel from a pre-inhalation position proximate the user interface to a complete dosage position proximate the inlet. The positioning of the dosage indicator in the complete dosage position indicates a complete administration of the dosage of medicament through the user interface. The dosage indicator includes a piston that is slidable along the rod in, and visible through, the flow channel as the dosage indicator is translated between the pre-inhalation position and the complete dosage position.
In another aspect, one embodiment of a method of delivering an aerosolized medication includes disposing an aerosolized dose of medicament in an interior volume of a chamber housing, inhaling through a user interface coupled to a chamber housing and thereby withdrawing the aerosolized dose of medicament from the interior volume, translating a dosage indicator in a flow channel in fluid communication with the chamber housing from a pre-inhalation position to a complete dosage position, observing the translation of the dosage indicator, and ceasing inhaling when the dosage indicator reaches the complete dosage position. In one embodiment, the dosage indicator is rotated as it is translated from the pre-inhalation position to the complete dosage position.
The various aspects and embodiments provide significant advantages over other medication delivery systems and methods. For example, and without limitation, the movement of the dose indicator allows users and caregivers to visually and/or audibly detect when the user has inhaled all of their medications. This feedback system may be particularly well suited for caregivers and users that may not be able to generate enough inhalation volume to inhale a complete dosage of medicament in one breath. The dosage indicator provides indicia to the user once the entirety of a predetermined, prescribed dosage of medicament has been inhaled, as opposed to prior devices that may only provide indicia that an inhalation flow is occurring, rather than indicating how much they have inhaled. Moreover, the dosage indicator is observable (e.g., visible and/or audible) to both the user and the caregiver in one embodiment.
The foregoing paragraphs have been provided by way of general introduction, and are not intended to limit the scope of the following claims. The various preferred embodiments, together with further advantages, will be best understood by reference to the following detailed description taken in conjunction with the accompanying drawings.
It should be understood that the term “plurality,” as used herein, means two or more. The terms “longitudinal” as used herein means of or relating to length or the longitudinal direction 2, for example between the opposite ends of the holding chamber or flow channel. The terms “lateral” and “transverse” as used herein, means situated on, directed toward or running from side to side (front and back of a worksurface), and refers to a lateral direction 4 orthogonal to the longitudinal direction. For example, the X direction may correspond to the longitudinal direction, which is horizontal when the device is in a use position, the Y direction may extend in a vertical direction when the device is in a use position, and the Z direction may correspond to the lateral direction, which is also horizontal when the device is in the use position. The term “direction” corresponds to an axis or line, rather than a vector. The term “coupled” means connected to or engaged with whether directly or indirectly, for example with an intervening member, and does not require the engagement to be fixed or permanent, although it may be fixed or permanent (or integral), and includes both mechanical and electrical connection. The terms “first,” “second,” and so on, as used herein are not meant to be assigned to a particular component so designated, but rather are simply referring to such components in the numerical order as addressed, meaning that a component designated as “first” may later be a “second” such component, depending on the order in which it is referred. For example, a “first” side may be later referred to as a “second” side depending on the order in which they are referred. It should also be understood that designation of “first” and “second” does not necessarily mean that the two features, components or values so designated are different, meaning for example a first side may be the same as a second side, with each simply being applicable to separate but identical components. As used herein: the term “substance” includes, but is not limited to, any substance that has a therapeutic benefit, including, without limitation, any medication; the terms “user” and “patient” includes humans and animals; and the term “aerosol delivery devices or system(s)” includes pressurized metered-dose inhalers (pMDIs), pMDI add-on devices, such as holding chambers, devices including a chamber housing and integrated actuator suited for a pMDI canister, nebulizers and dry powder inhalers.
In one embodiment, a force F may be applied to the canister, thereby moving the valve stem 122 of the pMDI canister to discharge a predetermined dosage of medicament from the discharge end, e.g., mouthpiece portion 118, of the pMDI receptacle in aerosol form into the interior volume 110 of the chamber housing 108. The aerosol medication particles within the interior volume 110 and chamber housing 108 are thereafter withdrawn through the outlet 112 by having the user/patient inhale through the interface 104.
The pMDI canister 106 contains a substance, preferably a medication suspension or solution under pressure. For example, the substance dispensed may be an HFA propelled medication suspension or solution formulation. Other medicaments, or medications, and propellants, such as CFC may also be used. It should be pointed out that while the described embodiments regard an aerosol delivery system for the delivery of an aerosolized medication from a pMDI, other aerosol delivery systems are contemplated that can be used within the spirit of the present invention. For example, it is contemplated that the completed dosage indicator may be incorporated with an aerosol delivery system such as existing ventilator systems, dry powder inhalers and nebulizers, in a manner similar to that described below. Examples of nebulizers that can be adapted to include such an indicator are disclosed in U.S. Pat. Nos. 5,823,179 and 6,044,841, the entire contents of which are incorporated herein by reference.
The present invention is not limited to the treatment of human patients. For example, it is contemplated that the complete dosage indicator may be incorporated in a mask for administering medication to animals, including for example and without limitation equines, cats, dogs, etc.
Referring to
The dosage indicator 160, 260 is moveable in the flow channel 150, 250 in the longitudinal direction 2 from a pre-inhalation position to a complete dosage position. In one embodiment, the dosage indicator 160 is translatable and rotatable in the flow channel 150 from the pre-inhalation position to the complete dosage position. The phrase “pre-inhalation position” refers to the position of the dosage indicator immediately preceding inhalation by the user through the aerosol delivery device, as shown for example in
For example, in one embodiment shown in
In various embodiments, the flow channel 150, 250 includes a track 180, 280, wherein the dosage indicator 160, 260 is moveable along the track 180, 280 between the pre-inhalation position and the complete dosage position. The dosage indicator may slide (translate) or roll (translate and rotate) along the track. As shown in
As shown in
The opening 154 that connects the channel to the chamber is designed to minimize resisting air flow between the channel and the chamber. This embodiment has a 10 mm by 9 mm opening, but it may be smaller or larger.
Referring to
The piston bushing 410 extends out from the disc 409 to prevent the disc from tipping and binding on the rod 402, resulting in smooth motion along the shaft. In various embodiments, the difference in diameters between the piston bushing and the shaft may be 0.1 mm-0.13 mm for a 2-5 mm long bushing, however, the difference in bushing diameters may be as small as 0.05 mm and as large as 1 mm, depending on the length of the bushing.
In one embodiment, the bushing inner diameter is about 3.4 mm and the rod outer diameter is about 3.18 mm for adult, infant and child. The bushing inner diameter could be as large as 6 mm and small as 1 mm. In one embodiment, the piston rod 402 shape is a cylindrical/tube shape, that extends along the length of the channel, connecting at the distal end of the channel and the proximal end. The rod may be made from stainless steel; however, it could also be made from PP plastic (or other polyolefins, nylons, MABS, polycarbonate).
The piston fin, or disc, may be any two-dimensional shape, but with the disc having an appropriate specified weight and edge gap for air to pass by (i.e., the channel should have a matching shape). Non-circular disc shapes may require an alignment feature on the rod to prevent the piston from rotating about the rod and touching the channel wall.
The rod 402 and opening 412 may be cylindrical, with the piston able to rotate about the axis of the rod, or the opening and rod may have non-cylindrical shapes, for example a keyed cross-sectional shape, such as a cross-sectional X shape, which prevents the piston from rotating about the axis. A first fitting 406 (e.g., hub) may be formed in a first end cap, which closes off one end of the channel. A second fitting 404 is formed in a valve assembly housing 420, which defines a second cap closing off a second end of the channel. The outlet 154 is formed in side wall of the channel. A slight clearance may be provided between the outer periphery of the piston 270 and the interior surface of the flow channel, which defines an elongated chamber, such that there is no interference, and attendant friction, created between the piston and the flow channel. Rather, the piston 270 slides freely along the guide, or rod 402. In one embodiment, the clearance between the periphery of the disc, or fin, and interior surface of the channel is between and including 0.1 mm and 2 mm. In exemplary embodiments, the radial clearance may be 0.25 mm for children/adults and 0.35 mm for infants, which allows the piston to slide freely though the channel without interfering with the peripheral edge, but also creates enough restriction such that the piston 270 may be pulled down the length of the channel.
In other embodiments, there may be contact between the piston and interior surface. In one embodiment, the interior surface of the flow channel may serve as the guide, with the outer surface of the piston riding along and being guided by the flow channel. In this embodiment, the rod may be omitted.
Referring to
In one embodiment, the flow channel includes a pair of laterally spaced tracks 180, each defined by a longitudinally extending slot or channel 200. In one embodiment, each track has an upper and lower surface 202, 204 defining the channel, as shown for example in
When the user 148 inhales through the user interface 104, such as the mouthpiece or mask, the aerosolized medication and air mixture disposed in the interior volume 110 of the holding chamber 102 is pulled through the inhalation valve 132, as air backfills/refills the holding chamber. In one embodiment, the air that re-fills the holding chamber 102 comes from the ambient environment through two or more inlets. In one embodiment, the backfilling air may come from three sources: through the inhaler 106 and inlet 116 (pMDIs and SMIs), through the inlet 156 communicating with the flow channel 150 and through one or more inlets 220 in the MDI adapter (backpiece) 114, which are spaced apart from the inlet 116. As air is pulled through the flow channel 150, the turbine 170 will begin to move from the pre-inhalation position, wherein the turbine is positioned at proximal end of the holding chamber, towards the distal end. The user's inhalation rate over time will cause the turbine 170 to hit a stop 212 at or near an end of the flow channel 150, which defines the complete dosage position, when the patient has inhaled enough volume to ensure that the patient has emptied the interior volume of the chamber of medicament. The volume may vary by age group, for example, and may be, or approximately be, 500 mL for adults, 300 mL for children and 150 mL for infants. To reset the dosage indicator 160 for the next use, the user simply tilts the holding chamber 102 (e.g., counterclockwise when viewed as shown in
Referring to the dosage indicator embodiment of
In an alternative embodiment, one or more third inlets 220 are provided in fluid communication with the interior volume 110. In one embodiment, a pair of inlets 220 are provided in the backpiece 114, with each inlet 220 each having a variable size opening. In one embodiment, a one-way, variable, valve 222 is disposed over the inlet. The inlet 220 and valve 222 may be incorporated directly into the holding chamber, or the inlet and valve may be incorporated into the backpiece or adapter 114 as shown for example in
The dosage indicator embodiment of
As shown in
When the user inhales through the mouthpiece, the aerosolized medication and air mixture from the chamber is pulled through the mouthpiece valve. The external air that replenishes the chamber during patient inhalation can come from 2 sources: through the inhaler (pMDIs and SMIs) or through the valved channel. As air is pulled through the channel, the piston 270 will begin to move from one end of the chamber towards the other end. The user's inhalation rate over time will cause the piston to hit the end of the channel when the patient has inhaled enough volume to ensure a patient has emptied the chamber of medicine. The impact of the piston against the end of the channel may provide an auditory signal that the dosage delivery is complete. The volume may vary by patient/age group, including for example approximately 500 mL for adults, 300 mL for children and 150 mL for infants. The one-way, variable valve 430 accommodates for this difference. Specifically, the valve 430 closes the inlet as the valve is biased against the valve seat 432 when the inhalation resistance through an inhaler is high, and remains open when the resistance through the inhaler is low. The valve response to air flow through the channel allows the valve to maintain a consistent airflow through the channel so the piston can indicate when enough air has passed through the chamber. The valve is tuned to remain closed for the lowest resistance inhalers, for example Pro-Air HFA inhalers with built in counters, and open to increase airflow as inhaler resistance is higher, for example Proventil HFA inhalers. The valve may be made from an elastomeric material such as silicone or TPE.
Tidal volumes and maximum inhalation rates vary between different age groups, where infants have the lowest inhalation rate and adults the highest. In one embodiment, the piston may have a high sensitivity to inhalation (<7 L/min) for all age groups. To accommodate a high sensitivity valve for a user with a high volume, the piston may move to the distal end of the channel too quickly, such that the overall channel length may need to be extended, e.g., 2 to 3 times the nominal length assuming the resistance due to the channel length increase was not too high. To accommodate and adjust for this difference, the valve and piston sensitivity may be varied. Moreover, the valve 430 allows for the friction between the piston and rod to be accounted for and adjusted accordingly.
In one embodiment, the dosage indicator assembly, otherwise referred to as a breath tracker assembly, may be made of five (5) injection molded and/or extruded components: the piston, a channel top/cover, a channel base (which may be integrated into the chamber body), a front cover/valve seat and the channel valve. The front cover subassembly may be made of two or more different components.
The valve housing 420 includes a front cover 440 placed on the front of the channel to prevent the piston from falling out during use. The front cover 440 may include and define the valve seat 423. The front cover 440 may include a pair of arm 442, defining guides, that slidingly engage tracks 450 on a valve holder 446, which includes an upstanding fulcrum member 448, which engages and applies a preload to the valve 430. The valve holder holds the valve in place to allow the valve to throttle the airflow through the channel depending on what pMDI is being used with the chamber. The front cover 440 may include openings 424 to allow air flow into the channel. The pre-load arm, or fulcrum 448, biases the valve 430, configured as a flap in one embodiment, slightly toward the openings 424. The front cover and valve seat may be made from a variety of materials, such as metal or plastic screen.
In one embodiment, the valve 430 is configured as a thin flexible flap, which is offset from the valve seat in a normally open position. When the patient inhales, the airflow increases through the gap between the valve and the valve seat. Depending on the age group and pMDI used, the valve may partially or fully close against the valve seat, restricting the airflow to the channel. Even in a fully closed position, in one embodiment, the valve may not completely prevent air flow through the inlet, for example a gap may be left, or various leak openings may be provided to maintain some minimal air flow. While a flap embodiment if shown, the valve may also be configured as a duckbill valve, ball valve, umbrella valve, etc.
As shown in
In one embodiment, the valve 430 and valve seat 432 may be fixed for a particular user target, for example a particular age range. In other embodiments, the valve assembly may be adjustable. In one embodiment, at the time of assembly or upon first use by the patient, a one-time adjustment would be made which would involve positioning the 430, valve seat 432, inlet opening and/or another feature (e.g., fulcrum 448) to allow for a change in airflow through the channel. The valve would then behave according to the desired specification without the need for unique valve seat components for each age range. For example, as shown in
In this way, in one embodiment, the valve assembly includes a valve 430 disposed adjacent the inlet of the flow channel, wherein the valve is moveable from a normally open position to an inhalation position in response to inhalation by a user. The valve at least partially closes the inlet opening when moved to the inhalation position. The valve assembly includes a fulcrum member 448 biasing the valve to the normally open position, i.e., applying a pre-load to the valve. The valve assembly is adjustable between a plurality of settings to vary the flow in the flow channel.
With either embodiment, and during operation, the user 148 holds the chamber in the horizontal position, such that gravity does not play an unintended role in the movement, or resistance thereto, of the turbine 170 or piston 270. In the embodiment of
In other embodiments, the flow channel and track may not be linear, but rather follow a curved or curvilinear path, for example a circular path, which may lie in the horizontal plane for example. For example, the flow indicator may follow a circular path wherein the pre-inhalation and compete dosage positions are adjacent.
Tidal volumes and max inhalation rates vary between different age groups, where infants have the lowest and adults the highest. Ideally the turbine 170 and piston 270 would have a high sensitivity to inhalation (<7 L/min) for all age groups, however, high sensitivity may cause the turbine to move to the distal end of the channel, or complete dosage position, too quickly since the length of the channel may be limited, for example if integrally formed with the holding chamber. In one embodiment, the adult turbine flow channel 150, 250 may be much longer (˜2-3×) so as to be able to detect very low inhalation rates (<7 L/min), assuming the resistance due to the channel length increase was not too high. By varying the turbine sensitivity, the turbine 170 and piston 270 may be optimized to work for the correct inhalation volumes of the three different patient groups. The turbine's weight may be reduced for high sensitivity. For example, in one embodiment, the turbine blades 186 may be thinned, and the diameter of the fins is reduced. Overall, a lower moment of inertia is desired for high sensitivity. Turbine blade diameters above 12 mm may become less sensitive as the fins require more material and less weight.
The turbine movement is highly sensitive to airflow since the turbine is very light, but also there is minimal friction restricting the movement of the turbine, as the rack 206 and pinion 188 design forces the turbine 170 to roll at a fixed rotation to distance rate. In other embodiments, the dosage indicator may slide in the track, with attendant friction providing resistance.
Air passing through the flow channel from the inlet 152 to the outlet 154 causes the turbine 170 to rotate and translate in the flow channel 150. Because the turbine 170 is contacting the channel via the pinion 188, the turbine travels along the channel at a much lower speed than the linear speed of the tip of the blade 186 of the turbine. In one embodiment a smaller diameter pinion 188 causes the turbine to spin more times to travel the distance of the channel, therefore allowing design control of the turbine response. As shown in
A primary source of drug delivery feedback is by the user observing, for example visually observing or seeing the turbine 170 or piston 270 move to the end of the track or flow channel 150 and stop. The turbine 170 or piston 270 may be made from a colored (non-clear or white) plastic (e.g., black, red, green, orange, blue, etc.) to provide contrast to the user, so their eyes do not need to focus on the turbine features, but rather see the different color object. The turbine or piston material may be mixed with a glow in the dark additive, or a glow in the dark coating may be applied, so that the caregiver or user can see the turbine 170 or piston 270 move when administering medications in the dark.
Another source of feedback comes from the sound that the turbine 170 makes as it moves along the flow channel 150 due to the pinion teeth 190 rolling over the teeth 207 of the rack. In this way, observing the translation of the dosage indicator 160 includes listening to the translation of the dosage indicator in the flow channel as the dosage indicator rotates. As such, the term “observing” refers to seeing or listening. The sound will indicate to the user if the turbine is moving, since it makes a subtle rattling sound. In addition, when the turbine hits the end of the channel, engaging for example the stop 212, and thereby reaches the complete dosage position, the turbine 170 provides a different audible queue to the user/caregiver indicative of the position being reached.
In one embodiment, the dosage indicator assembly incudes a plurality (shown as four) of components, each of which may be injection molded: the turbine 170, a flow channel top/cover 261, a channel base 262 and a front cover 264. The channel top/cover and bottom/base may be coupled, for example by snap or sliding fit/interface and/or with adhesive. Each of the top and bottom includes a horizontal wall defining one of the upper and lower surfaces 202, 204 of the track. In another embodiment, the flow channel part may include a pair of side components. The base component defines the bottom half of the channel, including the track and rack teeth. The base component may be made separate from or integral with the chamber body. If separate, the base component may be coupled to the chamber body with insert portions/guide, tabs, adhesive or other fasteners. Once assembled, the cover and base define the channel. In one embodiment, the flow channel may be one piece, made for example from an extrusion, with caps positioned at opposite ends thereof.
After the turbine 170 is disposed in the channel, a front cover 264 may positioned over and secured to the front of the flow channel to prevent the turbine 170 from falling out. The front cover 264 may have holes to allow air flow into the turbine channel and define the inlet 152. The front cover may be made from a variety of materials, such as metal or plastic screen. In this way, the front cover maintains the turbine 170 in the flow channel such that the turbine does not pose a choking hazard. The flow channel 150 may be detachable from the chamber body so the chamber body may be easily cleaned. The flow channel has an outlet 154 which is mated/communicates with and overlies the inlet 156 in communication with the holding chamber.
The channel assembly, and the top cover in particular, may be made from a transparent or translucent material, like polypropylene (PP) plastic (or possibly other polyolefins, nylons, MABS, polycarbonate), so that the user may see the turbine move along the length of the flow channel. As mentioned, the turbine 170 may be a contrasting color (e.g., black or a vibrant color) relative to the color of the holding chamber and flow channel. The turbine sensitivity is dependent on weight, therefore a lightweight plastic like PP may allow the turbine to be more sensitive than if it were made from a higher density plastic such as PET.
The turbine 170 includes the shaft 184, configured with a pair of pinion gears 188 at opposite ends thereof, that defines a laterally extending rotation axis 189, which is perpendicular to the longitudinally extending flow channel and track. The plurality of branching fin blades 186, extend radially outwardly from the shaft 184 and are arranged in a Savonius, or drag, design (ex, straight fins, helical fins, cup design). In one embodiment, the turbine 170 is configured with five blades 186. Other embodiments may be configured with or between 3 and 8 blades.
The effective turbine diameter (distance across/between the tips of the fins when viewed along the axis of the turbine, or the diameter of the space filled by the rotating turbine) is 8.6 mm 7.2 mm and 6.6 mm, for adult, child and infant turbines, respectively, but may be varied by 1-2 mm each. The turbine diameter dictates the length of the blades/fins, which impacts the turbine weight and therefore sensitivity to airflow. The weight of the adult, child and infant turbines may be 0.077 g, 0.046 g, and 0.033 g, respectively, but may be up to and including 0.125 g, for example as being suitable for adults. The turbine blade/fin thickness may be varied to increase or decrease the weight of the turbine, therefore influencing the sensitivity of the turbine. The adult or infant blade/fin thickness may be between 0.1 mm and 0.6 mm. In various embodiments, the thickness of the blades/fins for adults is 0.35 mm, 0.25 mm for children and 0.20 mm for infants. For the adult, child and infant design, the blades/fins may have a curvature radius between 2 mm and 6.5 mm, with 2.5 mm being suitable.
The shaft 184 extends past the length of the blades 186 and is formed in the shape of the pinion 188. In one embodiment, the length of the shaft or pinion is around 2.5 mm, which may be selected based on a balance of added weight and friction as turbine length increases. The length of the pinions may be between and including 0.5 mm and 5 mm.
The pinion 188 may have various number of teeth 190, for example between 4 and 7 teeth, with 5 teeth being suitable in one embodiment. More teeth may help prevent the turbine from popping out of the tracks. The pinion diameter, or outer circumferential periphery of the pinion gear 188 and teeth 190, may be between and including 0.5 mm to 2.5 mm, with various embodiments having a diameter of between and including 1 mm and 1.75 mm, which offers a suitable ratio between the outer fin diameter and the pinion diameter. In one embodiment, the pinion gear has a 1.75 mm.
The profile of the outer surface 276 of the flow channel may be rounded for aesthetics and to improve the tactile feel and cleanability. To maximize space within the curved channel, the turbine 170 has a rounded profile when viewed perpendicular to the turbine axis, maintaining a uniform clearance from the channel. The length of the flow channel 150 and cross-sectional shape are shaped to conform to the shape of the turbine, while leaving a 0.5 mm gap between the blades and the interior surface of the flow channel 150 to prevent contact. The opening 152, or inlet that connects the channel to the chamber minimizes the resistance of air flow between the channel and the chamber. In one embodiment, the opening 152 is 10 mm by 9 mm, but the opening may be smaller or larger.
During operation, the method of dispensing the medication includes disposing an aerosolized dose of medicament in an interior volume 110 of a chamber housing, for example by actuation the inhaler 106, which release a predetermined, metered dosage of medicament. The medication may be dispensed into the holding chamber while the interface is engaged with the patient, or beforehand. The method further includes inhaling through the user interface 104 coupled to the chamber housing and thereby withdrawing the aerosolized dose of medicament from the interior volume, translating the dosage indicator 160, 260 in the flow channel 150, 250 in fluid communication with the chamber housing from the pre-inhalation position to the completed dosage position as shown in
The flow rate at which the turbine 170 or piston 270 is designed to begin moving is called the “trigger flow rate”. This flow rate for adults could be between 5-30 L/min, 5-20 L/min for children and 5-10 L/min for infants, but ideally at 15 L/min, 10 L/min and 5 L/min respectively. The weight, pinion diameter, channel length, channel cross-sectional area, backpiece valved hole size and other various features may impact the turbine's trigger flow rate. In one embodiment, the holding chamber has three inlets: through the channel, the inhaler/receptacle and the valve. For each of the age variant designs (adult, child, and infant), the turbine and channel are designed to begin moving at a given pressure based on the average tidal breath flow rates.
In an alternative embodiment, a sliding dial 300 aligns with various dial numbers, or indicators 304, to vary the size of an opening 302 defining an inlet in the backpiece 114. For example, the indicators may be configured as alphanumeric characters, such as letters, numbers and/or as other shapes or symbols, which may be identified by different colors. Before use, the user aligns the dial 300 with the corresponding inhaler setting, using the indicators 304. The inhaler setting may be listed on the inhalation device, instructions accompanying the device or inhaler, as well as online. At the trigger flow for adults, the dial opening 302, or inlet 220, has an isolated flow rate of 12 L/min at setting 3 (max setting, fully open), and a flow rate of 8 L/min at setting 2 (mid setting, partially open) and OL/min at setting 1. While the embodiment shown in
In other embodiments, a smartphone or computer camera may capture video of the breath tracker feature moving to deliver real-time feedback of drug delivery performance through a user interface such as a smartphone or tablet via bluetooth. Alternatively, various sensors and a controller, incorporating software, may detect the type of inhaler being used and track the breath tracker piston's change in position over time, relative to the channel. With this information, a variety of performance metrics may be calculated, including peak inhalation rate, volume inhaled, inhalation before actuation, neck and head posture during treatment. The controller and output may provide tips to improve the user's inhalation technique for subsequent treatments.
For child and infant chambers, the use interface may provide or incorporate a story, or interactive game, which requires the user to use their inhaler and chamber to complete the story by making the breath tracker travel the whole length of the channel. For example, the interactive story may be viewed through a virtual reality headset, and augmented reality could integrate the use of the chamber with the story.
Although the present invention has been described with reference to preferred embodiments, those skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. As such, it is intended that the foregoing detailed description be regarded as illustrative rather than limiting and that it is the appended claims, including all equivalents thereof, which are intended to define the scope of the invention.
This application claims the benefit of U.S. Provisional Application 63/342,452, filed May 16, 2022 and entitled “Aerosol Delivery Device With Completed Dosage Indicator,” the entire disclosure of which is hereby incorporated herein by reference.
Number | Date | Country | |
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63342452 | May 2022 | US |