Therapeutic Powder Applicator

Abstract

A therapeutic powder applicator and method of operation are described. In some embodiments, a first gas flow can flow through a distal porous portion of a chamber containing a therapeutic powder. The gas can fluidize and entrain the therapeutic powder and cause the entrained powder to flow through an outlet in fluid communication with the chamber.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 63 / 046,176, filed June 30, 2020, the disclosure of which is incorporated by reference in its entirety herein.

[0002] Field

[0002] The disclosed embodiments relate to therapeutic powder applicators and related methods of use. [Background technology]

[0003] background

[0003] Powder applicators are used in many different applications to apply various types of powders to desired surfaces, including the delivery of therapeutic powders to desired locations on a subject for therapeutic purposes. The powders delivered using these applicators tend to be light, low density powders with Hausner ratios between 1.00 and 1.18. Some applicators fluidize the powder by directing a flow of gas through the entire bulk of the mass of particles, such as onto the upper free surface of the powder with the entire bulk positioned vertically below the flow of gas applied during operation, or from opposite an opening in a chamber containing the powder. However, these types of structures may not adequately fluidize powders that are more difficult to fluidize than the powders mentioned above. Summary of the Invention [Means for solving the problem]

[0004]

[0004] In one embodiment, the therapeutic powder applicator includes a chamber configured to contain a therapeutic powder, at least a distal portion of the chamber including a plurality of holes, a first source of pressurized gas in fluid communication with the chamber via the plurality of holes in the distal portion of the chamber, and an outlet in fluid communication with the chamber.

[0005]

[0005] In one embodiment, the therapeutic powder applicator includes a chamber configured to contain a therapeutic powder, at least a distal portion of the chamber including a plurality of holes, a first gas inlet, and an outlet in fluid communication with the chamber, the first gas inlet in fluid communication with the outlet via the plurality of holes in the distal portion of the chamber.

[0006]

[0006] In one embodiment, a method of applying a therapeutic powder includes flowing a first gas flow through a plurality of holes in a distal portion of a chamber containing the therapeutic powder, entraining the therapeutic powder in the first gas flow, and flowing the entrained therapeutic powder through an outlet in fluid communication with the chamber.

[0007]

[0007] It should be appreciated that the foregoing concepts and the additional concepts described below may be arranged in any suitable combination, as the disclosure is not limited in this respect. Furthermore, other advantages and novel features of the present disclosure will become apparent from the following detailed description of various non-limiting embodiments when considered in conjunction with the accompanying figures.

[0008]

[0008] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown in various figures may be represented by a similar numeral. For clarity, not every component in every drawing is numbered. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view of one embodiment of a powder applicator. [Diagram 2]

[0010] FIG. 1 illustrates a cross-sectional view of one embodiment of a powder applicator. [Diagram 3]

[0011] FIG. 2 is a cross-sectional view of an embodiment of a powder applicator nozzle. [Figure 4A]

[0012] FIG. 13 is a cross-sectional view of an embodiment of a powder applicator including two flow channels of different orientation. [Figure 4B] FIG. 1 is a cross-sectional view of one embodiment of a powder applicator including two flow channels of different orientation. [Figure 4C] FIG. 1 is a cross-sectional view of one embodiment of a powder applicator including two flow channels of different orientation. [Diagram 5]

[0013] FIG. 13 is a cross-sectional view of an embodiment of a powder applicator including two flow paths and a valve. [Figure 6]

[0014] FIG. 1 illustrates a cross-sectional view of one embodiment of a powder applicator. [Figure 7]

[0015] FIG. 13 is a cross-sectional view of an embodiment of a powder applicator having two gas sources. [Figure 8]

[0016] 1 is a photograph of one embodiment of a powder applicator used to apply powder to areas of different sizes. [Figure 9A]

[0017] FIG. 1 is a perspective view of one embodiment of the powder applicator, with the handle in a first position; [Figure 9B]

[0018] FIG. 9C is a perspective view of the powder applicator of FIG. 9B, with the handle in a second position. [Figure 10]

[0019] FIG. 13 is a cross-sectional view of an embodiment of a powder applicator having a rotatable handle. [Figure 11]

[0020] FIG. 13 is a cross-sectional view of another embodiment of a powder applicator having a rotatable handle. [Figure 12A]

[0021] FIG. 1 is a perspective view of one embodiment of a powder applicator handle. [Figure 12B]

[0022] FIG. 1 is a perspective view of an embodiment of a powder applicator having a valve. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010]

[0023] Therapeutic powders used for different applications may differ in both particle size and density. These properties affect the flow characteristics of the powder, i.e., flowability. The Hausner ratio can be used to evaluate the flowability of a powder, which is calculated by dividing the measured tap density of a powder by its bulk density. In general, the lower the Hausner ratio, the better the flowability. For example, powders with Hausner ratios between 1.00 and 1.18 are considered to exhibit excellent to good flow properties, while powders with Hausner ratios above 1.18 are considered to exhibit fair to poor flow properties. There may also be other powder characteristics such as particle morphology, basic flowability energy (BFE) (mJ), air permeability energy (AE) (mJ), air permeability index (AE), wall friction angle (WFA), compressibility, electrostatic charge, moisture content, and other suitable parameters that may result in a decrease in the overall flowability of the powder. Particles with poor flowability are relatively difficult to fluidize and are not suitable for certain applications.

[0011]

[0024] Hemostatic powders are therapeutic powders used to manage or stop bleeding. These powders are commonly applied by applicators that can use a stream of gas to guide the powder toward and over the bleeding site. Existing applicators use relatively high pressure and / or high velocity gas and are generally effective at fluidizing and applying relatively small particle size and / or relatively low density hemostatic powders. Such hemostatic powders may exhibit a Hausner ratio of 1.00 to 1.18. However, these small particle size and / or low density hemostatic powders may not be effective at breaking the surface tension of the flowing blood and therefore may not reach the desired location under the flowing blood. Therefore, in certain applications, it may be advantageous to use larger and / or denser powders that can break the surface tension of the flowing blood. In addition to particle size, density, and Hausner ratio, other particle properties including, but not limited to, particle morphology, basic flowability energy (BFE) (mJ), air permeability energy (AE) (mJ), air permeability index (AE), wall friction angle (WFA), compressibility, electrostatic charge, and moisture content can also improve the ability of a hemostatic powder to penetrate blood, but reduce the ability of the powder to be effectively fluidized in existing high pressure and / or velocity applicators. However, the inventors have recognized that existing high pressure applicators are generally not effective at fluidizing and applying powders having one or more of the above properties that can improve their ability to penetrate blood.

[0012]

[0025] In view of the above, the present inventors have recognized the advantages of an improved therapeutic powder applicator capable of handling a variety of different types of powder. Such an applicator may be configured to effectively fluidize and apply therapeutic powder at a variety of pressures and / or velocities ranging from relatively high pressures and / or velocities used in existing applicators to relatively low pressures and / or velocities below those of existing applicators. In some embodiments, such an applicator may also enable the therapeutic powder to be applied with a variety of spreads, for example, allowing targeted application to both small and / or large areas. Thus, in some embodiments, the operation of the applicator may be modified to effectively dispense hemostatic powder with desired precision and / or control to target locations that may vary in size from large to small areas. In contrast, typical applicators use relatively high pressures and / or velocities of gas that are generally effective in fluidizing and applying hemostatic powder to large target areas.

[0013]

[0026] In view of the above, the inventors have recognized the advantage of an improved therapeutic powder applicator capable of controllably delivering a variety of different types of powders. In some cases, this may enable delivery to either a large and / or small target area. In such embodiments, the applicator may be configured to effectively control the area of ​​delivery by controlling the pressure and / or velocity of the gas used to entrain the particles, which may in some cases be a relatively low pressure and / or velocity compared to typical applicators.

[0014]

[0027] In certain embodiments, the therapeutic powder applicator includes a chamber configured to contain a powder, such as a therapeutic powder (e.g., a hemostatic powder). A portion or the entirety of the chamber may be made of a porous material. A first pressurized gas source may be in fluid communication with the chamber through the porous material of the chamber. Additionally, an outlet of the chamber may be in fluid communication with the interior volume of the chamber. In such embodiments, a first gas flow from the first pressurized gas source may flow into the chamber through the porous material. Upon entering the chamber, the gas flow may fluidize and entrain the powder before exiting the outlet of the chamber to dispense the powder from the applicator. In some embodiments, the gas flow may be delivered to the chamber such that the gas flow and entrained particles flow into the chamber through a porous material forming a portion of the chamber at an angle to the direction of exiting the chamber and / or at a location proximate a stationary distal portion of the chamber disposed between the opening and a proximal end of the chamber opposite the opening. Further, in some embodiments, this distal portion of the chamber may be configured such that when the device is operated, the distal portion of the chamber and the opening can be oriented at least partially vertically downward relative to the local direction of gravity to maintain powder adjacent the opening and porous portion of the chamber through which gas flows.

[0015]

[0028] In some embodiments, it may be desirable to further increase the turbulence of the gas flow entering the chamber, i.e., the mixing of the gas and particulates within the chamber. In such embodiments, the applicator may include a vortex chamber disposed adjacent the opening of the chamber. The vortex chamber may be configured to concentrate the incoming gas flow through a porous material forming a portion of the chamber proximate the exit location. Without wishing to be bound by theory, this may improve aeration and fluidization of the powder proximate the exit, thereby increasing the amount of delivered material per actuation.

[0016]

[0029] In certain embodiments, it may be desirable to entrain the fluidized powder in a separate gas flow. Such a configuration may help dispense the fluidized powder in a desired distribution pattern from the outlet of the applicator. Such an applicator may include at least a second gas flow separate from the first gas flow that passes through the chamber of the applicator and fluidizes the powder contained therein as described above. During operation, the first gas flow with the entrained powder may be combined with the second gas flow at a point downstream from the chamber. Thus, the entrained powder may be dispensed through the outlet of the applicator by the combined flow of the first and second gas flows. It should be understood that the pressure source of this second flow path may be the same or different from the pressure source used to fluidize the powder.

[0017]

[0030] During application, it may be desirable to adjust the spread or coverage of the powder applied by the applicator. For example, it may be desirable to start with a small spread so that the powder may be dispensed over a first small area, and a large spread where the powder may be dispensed over a second larger area. Furthermore, in some cases, it may be desirable to dispense a larger amount of powder, while in other instances, it may be desirable to dispense a smaller amount of powder. In some embodiments, the above dispensing parameters may be adjusted by adjusting the relative flow rates of gas through the first and second flow paths of the applicator described above. This may be accomplished by changing the relative flow resistance of one or both flow paths (e.g., a variable flow resistance valve), changing the flow rate of gas from an associated pressure source, and / or any other suitable method of controlling the relative flow rates of gas between the different flow paths. For example, in one exemplary embodiment, the variable resistance valve may be fully opened to allow maximum flow through the second flow path in a first mode of operation, partially closed to allow reduced flow through the second flow path in a second mode of operation, and fully closed to prevent gas flow through the second flow path in a third mode of operation.

[0018]

[0031] As described above, at least a portion of the chamber may be made of a porous material. In some embodiments, the porous material may be configured such that the porous material is permeable to gas from a first pressurized gas source and impermeable to powders of a predetermined particle size range. Thus, the porous material may retain the powder within the chamber and prevent the powder from flowing back toward the associated pressurized gas source. The applicator may be configured such that the powder is in the chamber when the applicator is not operating (e.g., when the first pressurized gas source is not operating to deliver gas to the chamber). The porous material may correspond to any suitable material and / or structure that includes a plurality of open pores extending from one side of the material to another opposite side of the material. In some embodiments, a plurality of holes may be formed in the material by drilling, molding, laser ablation, or using any other suitable manufacturing technique. In other embodiments, the porous material may be a porous membrane that may correspond to a woven, non-woven, or other suitable membrane structure. Additionally, in some cases, the diffusion properties of the porous membrane may be changed by sintering the porous membrane. Thus, in some embodiments, the porous material may include a sintered porous membrane. In view of the above, it should be understood that any suitable type of porous material having a suitable pore density and pore size may be used in the various embodiments described herein, as the disclosure is not limited in this respect.

[0019]

[0032] As discussed above, the entire chamber or only a portion of the chamber may be constructed of a porous material. In embodiments where only a portion of the chamber is porous, the remaining portion of the chamber may be constructed of any suitable non-porous material, including plastic, glass, metal, and the like. The porous and non-porous portions of the chamber may have a connecting surface. In certain embodiments, the porous and non-porous portions of the chamber may be selectively connectable at the connecting surface. This configuration may allow the chamber to be selectively opened and closed, allowing therapeutic powder to be added or removed as desired. Such embodiments may be configured for reuse. In other embodiments, the various portions of the chamber may be integrally formed and / or permanently connected to one another. In such embodiments, the chamber may be provided with a particular amount or dose of the desired therapeutic powder, and once that dose is depleted, the chamber may be removed from the applicator, discarded, and optionally replaced with a new chamber containing a new dose of therapeutic powder. Thus, the applicator may be configured for either single use or multiple use, as the disclosure is not limited in this manner.

[0020]

[0033] The applicators disclosed herein may be used to fluidize and dispense a wide range of therapeutic powders of various particle sizes and densities. The inventors have shown in tests that the lower pressures and / or velocities provided by certain embodiments described herein may enable the use of relatively large size and / or high density powders. For example, the applicators may be configured to fluidize powders having particle sizes of 100 μm or more, 200 μm or more, 300 μm or more, and / or any other suitable size or more. The powders may also have particle sizes of 700 μm or less, 600 μm or less, 500 μm or less, and / or any other suitable size or less. Combinations of the above ranges are also contemplated, including, for example, powder particle sizes between 100 μm and 700 μm. In addition to the above, in some embodiments, the disclosed applicators may enable the use of combinations of multiple types of powder particles, each of which may be of similar or different particle characteristics, i.e., particle size, density, etc. In addition to the above, it should be appreciated that in some embodiments, the powders may have a Hausner ratio greater than 1.18, although the applicator may be configured to fluidize and dispense powders having a Hausner ratio of 1.18 or less. For example, the Hausner ratio of one or more powders contained within the applicator may be 1.18 or greater, 1.2 or greater, 1.3 or greater, and / or any other suitable ratio or greater. Similarly, the Hausner ratio may be 1.4 or less, 1.3 or less, 1.2 or less, and / or any other suitable ratio or less. For example, combinations of the foregoing including Hausner ratios of 1.18-1.4 are contemplated, although both ratios above and below the above-mentioned ratios are also contemplated. Additionally, although specific particle sizes are set forth above, particles both above and below the above-mentioned particle sizes are contemplated, as the disclosure is not so limited.

[0021]

[0034] As noted above, in some embodiments, the applicator may be configured to utilize a pressure lower than that of a standard applicator. Suitable pressures that may be provided from the pressure source to the chamber and / or other portions of the applicator may be 2 millibar (mbar) or more, 3 mbar or more, 5 mbar or more, 10 mbar or more, 20 mbar or more, and / or any other suitable pressure or more. The pressure provided by the pressure source may also be 40 mbar or less, 30 mbar or less, 20 mbar or less, 2 mbar or less, and / or any other suitable pressure or less. Combinations of the foregoing are also contemplated, including, for example, a pressure source configured to provide a gas flow at a pressure between 2 mbar and 40 mbar. Of course, different combinations of the above ranges as well as pressure ranges both above and below the above pressure ranges are also contemplated, as the disclosure is not so limited.

[0022]

[0035] The pressure sources described herein may represent any suitable type of pressure source capable of providing a pressurized gas flow to one or more portions of the powder applicator. Suitable pressure sources may include, but are not limited to, a central pressure source such as a compressible bellows, a gas canister, a pressurized gas port, a pump, and / or any other suitable pressure source capable of providing pressurized gas to the applicator. Pressure sources may include atmosphere, CO 2 , hydrofluoroalkane, and / or any other suitable gas. Depending on the particular embodiment, the pressure source may be directly coupled to a portion of the applicator, connected to the applicator via a hose, and / or attached in any other suitable manner for providing fluid communication between the desired portion of the applicator and the one or more pressure sources. The one or more pressure sources may also be configured to provide a continuous flow of gas or a predetermined amount of gas depending on the desired application as described in more detail below.

[0023]

[0036] In some applications, it may be desirable for the applicator to be able to fluidize the powder contained therein in several different orientations. Generally, therapeutic powder is more easily fluidized when in contact with the porous portion of the chamber through which the gas flows. Therefore, it may be desirable to orient the chamber of the applicator such that the powder remains in contact with the porous portion of the chamber during use. To facilitate this placement of the powder, in some embodiments, it may be advantageous to angle the longitudinal axis of the chamber so that the longitudinal axis of the chamber can be angled with respect to an axis through the outlet of the application that may be parallel to the flow exiting the outlet. Tilting the chamber with respect to the outlet may help to maintain the powder in the desired portion of the chamber. Suitable angles between the axis of the outlet and the longitudinal axis of the chamber may be 15° or more, 20° or more, 30° or more, 45° or more, 60° or more, 70° or more, 90° or more, 120° or more, and / or any other suitable angle or more. The angle of the longitudinal axis of the chamber relative to the axis of the outlet can also be 165° or less, 150° or less, 135° or less, 120° or less, 90° or less, 70° or less, 60° or less, and / or any other suitable angle or less. Combinations of the above are also contemplated, including, for example, angles between the longitudinal axis of the chamber and the axis of the outlet from 20° to 70°. Inclining the longitudinal axis of the chamber relative to the axis of the outlet can facilitate effective fluidization of powder in the chamber having different orientations of the applicator relative to the downward force of gravity, although embodiments in which the longitudinal axis of the chamber and the axis through the associated outlet of the applicator are parallel and / or coaxial with one another are also contemplated, as the disclosure is not so limited.

[0024]

[0037] In some embodiments, the applicator may include a handle. The handle may be configured to rotate relative to another portion of the applicator to accommodate different holding positions and / or orientations. For example, the handle may be configured to rotate relative to the chamber of the applicator such that the chamber may remain upright or otherwise oriented such that the powder remains in contact with the porous portion of the chamber during use. For example, a user may rotate the handle from a vertical orientation to a horizontal orientation, but the orientation of the chamber relative to gravity does not change. In some embodiments, the handle may be configured to rotate about a longitudinal axis of the applicator, which may allow the handle to "spin" relative to another portion of the applicator. For example, the handle may be configured to rotate about an axis of rotation parallel to an axis through the outlet.

[0025]

[0038] It should be appreciated that the handle of the applicator may be configured to rotate through any suitable angle, as the disclosure is not limited in this respect. For example, the handle may be configured to rotate through an angle of -180° or more, -135° or more, -90° or more, -45° or more, -30° or more, -15° or more, 0° or more, 15° or more, 30° or more, 45° or more, 90° or more, 135° or more, and / or any other suitable angle or more, relative to an initial configuration. The handle may be configured to rotate through an angle of -135° or less, -90° or less, -45° or less, -30° or less, -15° or less, 0° or less, 15° or less, 30° or less, 45° or less, 90° or less, 135° or less, 180° or less, and / or any other suitable angle or less. Combinations of the foregoing are also contemplated. In some embodiments, the handle may be configured to rotate more than 360°. In some embodiments, the handle may be configured to rotate in one or more directions, but is not limited thereto.

[0026]

[0039] In some embodiments, the handle may be configured to rotate in discrete increments. For example, the handle may be biased to preset angular positions that are separated by defined increments (e.g., 5°, 10°, 15°, 30° increments, or any other suitable increments). The discrete rotational increments may be achieved using a detent, tab and slot configuration, a ratchet mechanism, or any other suitable configuration configured to allow for discrete angular placement. In some embodiments, the handle may be configured to rotate continuously. For example, the handle may rotate about a bushing or bearing disposed between the handle and the outer housing of the applicator. In some embodiments where the handle is configured to rotate continuously, the handle may be locked at any desired rotational angle. The handle may be locked using a friction collar, thumbscrew, button, or any other suitable locking mechanism.

[0027]

[0040] In some embodiments, the proximal portion of the applicator may rotate with the handle as the handle rotates relative to the chamber, and the distal portion of the applicator may remain stationary relative to the chamber. For example, the proximal portion may include a pressurized gas source (e.g., a bellows) and a handle, and the distal portion may include a chamber and an outlet. The entire proximal portion may rotate relative to the entire distal portion as the handle rotates relative to the chamber. Thus, in such embodiments, the pressurized gas source may rotate with the handle as the handle rotates relative to the chamber. In such embodiments, a first portion of an overall flow path from the pressurized gas source to the outlet (e.g., a portion of the flow path within the proximal portion of the applicator) may rotate relative to a second portion of the overall flow path (e.g., a portion of the flow path within the distal portion of the applicator). The proximal and distal portions of the applicator (and / or the first and second portions of the overall flow path) may be rotatably coupled using any suitable coupling configured to enable relative rotation. For example, either the proximal or distal portion of the applicator may include a flange, and the other of the proximal or distal portion of the applicator may include a shelf and / or ledge configured to engage the flange. The interface between the proximal and distal portions of the applicator may include a gasket, O-ring, or other component configured to seal the interface between the first and second portions of the overall flow path to prevent or minimize leakage of pressurized gas.

[0028]

[0041] In some embodiments, the handle may be the only component that rotates when the handle rotates relative to the chamber. For example, the pressurized gas source may be fixed relative to the chamber such that the handle is configured to rotate relative to the pressurized gas source when the handle rotates relative to the chamber. In such embodiments, the overall flow path from the pressurized gas source to the outlet may not include parts that rotate relative to one another, since the handle may rotate about the overall flow path. Thus, such embodiments may not include gaskets, O-rings, or other sealing components.

[0029]

[0042] The applicator may include any suitable number, type, and / or configuration of valves configured to control the flow of fluid. In some embodiments, the applicator may include one or more one-way valves (also referred to as check valves or anti-return valves) configured to prevent backflow of fluid to the outlet. For example, if the applicator includes a bellows as the pressurized gas source, expanding the bellows from a compressed configuration (e.g., after delivering the therapeutic powder) may involve the generation of a vacuum pressure. Such vacuum pressure may draw gas and / or liquid from the area around the outlet back into the applicator through the outlet. Such backflow may be undesirable in that the area around the outlet may contain moist, humid gas and / or liquid that may adversely affect the performance of the applicator if it enters the interior of the applicator. Thus, the applicator may include a first one-way valve configured to allow gas to flow from the pressurized gas source to the outlet and configured to prevent fluid from flowing from the outlet to the pressurized gas source. The first one-way valve may be located at any suitable point along the flow path from the pressurized gas source to the outlet. For example, the first one-way valve may be located immediately downstream of the outlet of the pressurized gas source or proximal to the outlet, although other suitable locations are contemplated. In some embodiments, the applicator may include a second one-way valve configured to allow gas to flow into the applicator from the external environment. For example, the second one-way valve may be configured to allow gas to flow from the atmosphere surrounding the bellows to the applicator to replenish the bellows when the bellows expands from a compressed configuration, but may be configured to prevent gas from flowing from the bellows to the atmosphere when the bellows is compressed. The second one-way valve may be located at any suitable point along the flow path from the pressurized gas source to the outlet. In some embodiments, the second one-way valve may be located at a position upstream of the first one-way valve.

[0030]

[0043] It should be understood that the applicator may have a chamber of any suitable shape for containing the powder to be dispensed. However, in certain embodiments, the applicator chamber may have an elongated shape with a longitudinal axis extending along the length of the chamber. For example, the chamber may be generally cylindrical in shape with hemispherical ends. Such a shape may facilitate fluidization of the powder and dispensing through the outlet. For example, the shape may be free of sharp edges, corners, etc. that may impede the flow of gas and fluidization of the powder within the chamber. However, embodiments are contemplated in which sharp edges, corners, and other abrupt, discontinuous design features are present along the flow paths and / or within the applicator chamber, as the disclosure is not so limited. For example, there may be doglegs or other sharp bends along the flow paths connecting various flow paths and / or chambers to one another.

[0031]

[0044] In some embodiments, it may be desirable to dispense a predetermined amount of powder during actuation of a pressure source of the applicator. For example, as described in more detail below, actuation of a bellows or other pressure source in fluid communication with a porous chamber containing the powder may cause a predetermined amount of powder to be dispensed from the applicator for each actuation cycle. In one embodiment, this may be accomplished by flowing a predetermined amount of gas at a desired pressure through one or more flow paths of the applicator, dispensing a metered amount of gas from a pressurized gas source, or any other suitable method of dispensing a desired amount of gas at a desired pressure, as may occur during one actuation cycle of the bellows. This may allow for a substantially metered dispensation of powder from the applicator.

[0032]

[0045] The applicators described herein may be used to dispense any suitable type of powder, as the disclosure is not so limited. However, as noted above, in some embodiments, the various embodiments of the powder applicators described herein may be used to dispense a powder including one or more therapeutic compounds, which may be referred to as a therapeutic powder. As the disclosure is not so limited, a therapeutic compound for purposes of this application may represent any suitable material, including, but not limited to, any drug, agent, pharmaceutical, imaging agent, and / or biological agent, such as a protein, antisense molecule, and gene therapy viral vector. In certain embodiments, the therapeutic compound may be a hemostatic agent. The amount of therapeutic powder dispensed from the applicator may be selected such that an effective amount of the therapeutic compound may be dispensed at a desired location. When a therapeutic compound is present at a particular location in an "effective amount," this means that the concentration of the therapeutic compound is more than trace amounts and is sufficient to achieve a desired purpose, such as, for example, enabling detection of the therapeutic compound in a subject for diagnostic purposes, treating a disease or condition in the subject, and / or enhancing treatment of a disease or condition in the subject. In some embodiments, an effective amount of a particular therapeutic compound is present in an amount sufficient to reduce or alleviate one or more symptoms associated with a particular condition.

[0033]

[0046] Certain non-limiting embodiments will now be described in more detail with reference to the figures. It will be understood that the present disclosure is not limited to only the specific embodiments described herein, and that the various systems, components, features, and methods described with respect to these embodiments can be used either individually and / or in any desired combination.

[0034]

[0047] FIG. 1 illustrates a first embodiment of a therapeutic powder applicator 100. In this embodiment, the applicator is handheld and configured to be operated using a bellows 120 configured to function as a first source of pressurized gas. The bellows includes an internal compressible volume in fluid communication with a chamber 110 in which powder may be contained. The chamber is at least partially formed from a porous material as indicated by a porous material 112 including a plurality of holes 114 forming a lower portion of the chamber. In the embodiment shown, the chamber includes a second portion of a non-porous material 116 that is joined and connected to the porous material 112 at an interface 115 to form the overall chamber, although it is contemplated that the entire chamber may be made from a porous material. As previously mentioned, this interface may be selectively matable, allowing the chamber to be opened to allow therapeutic powder to be added to or removed from the chamber 110 as desired. In other embodiments, the porous material 112 and the non-porous material 116 may be permanently connected at the interface 115, or the chamber may be a single, integral component.

[0035]

[0048] Also as shown, the interior volume of the bellows 120 or other suitable pressure source is fluidly connected to the interior volume of the chamber through the porous material of the chamber via a first gas conduit 122. In the embodiment shown, the first gas conduit corresponds to one or more channels or gaps between the exterior surface of the chamber and the interior surface of the applicator's exterior housing 102 and an associated connector 104 disposed between the bellows and the housing chamber. The connector may include an inlet 121 to the housing and the first flow conduit. In this embodiment, the non-porous material 116 of the chamber 110 may help guide the first gas flow around the proximal portion of the chamber 110 as it flows from the bellows 120 at the proximal end of the applicator 100 toward the distal portion of the applicator. The porous portion of the chamber may be located distal to the non-porous portion of the chamber. Thus, a bellows or other pressurized gas source can deliver a gas flow to a distal portion of the chamber, which in this case can be an opening in fluid communication with the second conduit 132 located in the distal portion of the chamber. Alternatively, in some embodiments, the location to which the gas flow from the gas source is delivered can be a distal portion of the chamber located on one or more sides of the chamber extending between the proximal and distal ends of the chamber, such that in the initial fill condition the gas flow flows into the bulk of the powder rather than the proximal end of the chamber opposite the opening. Additionally, in some embodiments and as shown, the gas flow entering the volume surrounding the porous portion of the chamber can allow the flow of pressurized gas to enter the chamber along the entire porous portion of the chamber, which in this case corresponds to the distal portion of the chamber proximal to the opening of the chamber.

[0036]

[0049] In the above embodiment, the second conduit 132 is also in fluid communication with the applicator outlet 130. This can help prevent fluid flow from entering the chamber in a direction parallel to the direction of flow out of the chamber, which can aid in fluidizing the powder contained within the chamber. For example, depending on the particular configuration, the fluid flow from the bellows or other gas source may enter the chamber in a direction angled relative to the longitudinal axis of the chamber and / or the opening of the chamber. Suitable angles may include, but are not limited to, angles of about 15° to about 180° (i.e., in the opposite direction) such that the gas flow entering the chamber is not in the same direction as the gas flow and entrained particles through the opening of the chamber. However, angles both greater than and less than the above angles are contemplated, as the disclosure is not so limited. However, it should also be understood that embodiments are contemplated in which the direction of gas flow entering the chamber and the direction of gas flow and entrained particles exiting the chamber are parallel to one another.

[0037]

[0050] In the embodiment shown, both the longitudinal axis of the chamber 110 and the axis through the applicator outlet 130 are substantially parallel and coaxially aligned with one another along the illustrated axis 118. Furthermore, when the applicator is oriented with the outlet facing vertically downward relative to the local gravitational field, the porous material 112 forms the bottom of the chamber 110. When the applicator 100 is oriented in this vertically downward orientation or with a relatively small angular deviation from the vertical (e.g., less than 45 degrees from the vertical), the majority of the therapeutic powder contained within the chamber may be disposed in contact with the porous material 112 due to gravity acting on the powder. Without wishing to be bound by theory, the primary mechanism by which fluidization is achieved is that the flowing gas prevents friction between the particles and the inner surface of the chamber 110. Thus, the effectiveness of fluidization may depend on what percentage of the powder comes into contact with the porous material 112 as the gas flows through the porous portion of the chamber. Thus, the configuration shown in the first embodiment may be effective in fluidizing therapeutic powders when oriented vertically or when deviated from vertical by less than a certain angle (e.g., less than 45 degrees). However, it should be understood that the operation of the illustrated device is not limited to any particular angular range, as various shapes, relative sizes, amounts, and / or other suitable operating parameters of the porous material forming the chambers can be varied to provide different operating angular ranges for operation of the applicator.

[0038]

[0051] In operation, compression of the bellows 120 generates a first gas flow that flows through the first gas inlet 121 into the housing 102 of the applicator 100. From here, the first gas flow travels through the first gas conduit 122. The first gas conduit 122 passes gas around the chamber 110 from a proximal portion of the device near the bellows 120 to a distal portion of the device near the outlet 130 where the porous material of the chamber is located. Upon reaching the distal portion of the device, the first gas flow flows through a plurality of holes 114 formed in the porous material 112 of the chamber 110. After flowing through the porous material 112, the first gas flow fluidizes and entrains a therapeutic powder (not shown) that is present in the chamber 110 before flowing through an opening in the chamber into the second gas conduit 132. The entrained powder may then be dispensed from the outlet 130 along with the gas flow.

[0039]

[0052] In embodiments in which a bellows is used, the bellows may be configured such that a force applied to the bellows may affect the pressure and / or velocity of the gas delivered to the chamber or other portion of the applicator. This may further affect the fluidization and / or distribution characteristics of the applicator. For example, applying a large force or compressibility to the bellows may create a higher pressure, resulting in a larger amount of powder being fluidized and dispensed through the outlet to a smaller first area in a smaller distribution pattern. Conversely, applying a small force or compressibility to the bellows may create a lower pressure, resulting in a smaller amount of powder being fluidized and dispensed through the outlet to a second larger area in a wider distribution pattern. Of course, as previously mentioned, similar functionality may be obtained by controlling the pressure and / or flow rate of the gas from any other suitable pressure source.

[0040]

[0053] FIG. 2 illustrates a second embodiment of the applicator 100. In this embodiment, the applicator 100 is similar to the embodiment described with respect to FIG. 1. However, in this case, the applicator is configured to operate using gas provided by a pressurized gas source 120 other than a bellows. For example, a gas source or gas canister in an operating room / clinic may be fluidly connected to the applicator by an associated tubing 120a or other suitable connection that is in fluid communication with a first gas inlet 121 of the applicator. In this embodiment, the first gas inlet 121 includes a 90 degree elbow, although in other embodiments, any angle offset or straight connection may be used. The tubing may be attached to the first gas inlet by any suitable connection, including but not limited to a quick connect fitting, a threaded connection, an adhesive, a compression fitting, and / or any other suitable type of connection. In another embodiment, an appropriately sized canister may be attached to the housing 102 of the applicator 100 and fluidly connected to the first gas inlet 121. 1, the gas flow flows in the first gas conduit 122 from a proximal portion of the device near the first gas inlet 121 to a distal portion of the device near the outlet 130. At this point, the gas is able to flow within the porous material 112 of the chamber 110 where it is fluidized to entrain a therapeutic powder (not shown) before carrying the powder through the second gas conduit 132 and dispensing the powder through the outlet 130.

[0041]

[0054] FIG. 3 shows an isolated view of one embodiment of an outlet 130 of the applicator. In this embodiment, the outlet 130 includes a first inner wall 132a formed from a porous material that defines at least a portion of a channel 131 extending into the nozzle. The inner wall may be spaced apart from a second wall 132b of the nozzle disposed radially outward from the inner wall such that an interior volume 133 may be formed between the first and second walls. The walls are shown as cylindrical tubes. However, any suitable shape of wall and corresponding volume may be used. In the embodiment shown, the second wall may be made from a non-porous material and the first inner wall may include a plurality of holes 134 formed therein such that the interior volume disposed between the walls is in fluid communication with the channel extending into the nozzle via the plurality of holes formed in the first inner wall. It should be understood that any porous material may be used to form the inner wall including holes formed in a solid material, a porous membrane material, or any other suitable porous material. The nozzle may include an inlet 136 to the interior volume located at any point between the first and second walls, in some embodiments distal to the outlet 131, and in some proximal.

[0042]

[0055] During operation, a gas flow separate from the main gas flow through the channel 131 of the nozzle 130 may be provided from a pressurized gas source through the inlet 136 into the interior volume 133 between the first wall 132a and the second wall 132b. The pressurized gas source may be the same as or different from the pressurized gas source used to provide the main gas flow through the applicator nozzle. In either case, this gas may be at a higher pressure than the main gas flow through the channel of the nozzle, such that the gas flows from the interior volume through the holes in the first interior wall into the channel. This gas flow into the channel of the nozzle through the interior walls forming the channel may help retain powder entrained in the gas flow through the nozzle and may help prevent clogging of the applicator. Of course, while a particular nozzle design has been described in connection with the figures, it should be understood that any suitable type of nozzle may be used with the various embodiments of the applicator described herein, including nozzles that do not have the structures shown.

[0043]

[0056] 4A-4C show a third embodiment of a therapeutic powder applicator 100. Most notably, the third embodiment is configured to include a second gas flow path and includes an angular offset between the longitudinal axis of the chamber 110 and an axis through the applicator's outlet 130. In this embodiment, a bellows 120 is configured to be a first pressurized gas source. As with the previous embodiment, a bellows or other pressure source is in fluid communication with the porous portion of the applicator's chamber 110 containing the powder (not shown) through a first gas inlet 121 in fluid communication with a first conduit in fluid communication with a volume surrounding a porous material 112 forming a portion of the chamber. As with the previous embodiment, the first conduit may deliver a pressurized gas flow to a location proximate an opening of the chamber through which the gas and entrained particles can flow. In the embodiment shown, the outlet from the first conduit is directed toward the porous portion of the chamber at an angle different from the angle of the axis extending through an opening 132 formed in the chamber. The bellows may also be in fluid communication with a second flow path in the form of a second conduit 142 that bypasses the chamber. The flow paths connecting the bellows via the gas inlet to the first and second conduits may branch at a first branch 123. These separate first and second flow paths may recombine at a second branch 124 downstream of the chamber and the second conduit before passing through the outlet of the applicator.

[0044]

[0057] During operation, compression of the bellows 120 generates a first gas flow that flows into the interior of the applicator 100 through the gas inlet 121. Upon entering the applicator, the first gas flow encounters the first branch 123 where the gas flow splits into two different streams. As described above, the first gas flow enters the first gas conduit 122 and flows through the porous material 112 of the chamber 110 where the gas fluidizes and entrains the powder contained within the chamber. A separate second gas flow enters the second gas conduit 142 and flows along the second gas conduit 142 to the second branch 124 such that the second gas flow bypasses, i.e. does not flow through, the powder-containing chamber. Similarly, powder entrained in the first gas flow exiting through the opening 132 of the chamber can also flow to the second branch 124 where the entrained powder and the first gas flow are combined with the second gas flow. Depending on the relative velocities of the two gas streams, the second gas stream can aerosolize any powder entrained in the combined gas stream before exiting through outlet 130.

[0045]

[0058] As noted above, Figures 4A-4C also show the chamber 110 having a longitudinal axis that is angled relative to an axis extending through the outlet 130 of the applicator 100. In the illustrated embodiment, the angle between the longitudinal axis of the chamber and the outlet is approximately 45°, although other suitable angles may be used. The figures include dashed lines that represent a horizontal plane perpendicular to the direction of gravity. Figure 4A shows the applicator outlet tilted upward at an angle of approximately 45° relative to the horizontal plane, Figure 4B shows the applicator with the outlet tilted downward at an angle of approximately 45° relative to the horizontal plane, and Figure 4C shows the applicator outlet oriented vertically downward. In each of these three orientations, the longitudinal axis of the chamber is angled relative to an axis passing through the applicator outlet such that the portion of the chamber made of the porous material 112 may be located at the vertically lowest portion of the chamber. Thus, gravity acting on the powder contained within the chamber may keep the majority of the powder in contact with the porous portion of the chamber. As discussed above, maintaining the powder in contact with the porous portion of the chamber through which gas can flow can help ensure proper fluidization of the powder contained within the chamber. Thus, embodiments can allow for a wider range of effective operating orientations of the applicator compared to applicators in which the longitudinal axis of the chamber is aligned with an axis extending through the applicator outlet, similar to the embodiment shown in Figures 4A-4C in which the longitudinal axis of the chamber 110 is at an angle to the axis of the outlet 130.

[0046]

[0059] FIG. 5 shows another embodiment of the powder applicator 100. This is similar to the embodiment described above in connection with FIGS. 4A-4C. However, a variable fluid restriction, such as a valve 125, may be disposed along the second gas conduit 142 between the first branch 123 and the second branch 124. This valve may be configured to adjust the relative flow resistance and therefore the flow rate of gas through the first conduit 122 and the second conduit 142. Depending on the desired operation, the variable flow resistance may be manipulated to provide a variable flow resistance in the second conduit bypassing the chamber that is less than, equal to, and / or greater than the flow resistance in the first conduit and associated chamber. Furthermore, in some cases, the variable flow resistance may be used to close off the second conduit, in which case the operation of the applicator may be similar to that described in the previous embodiment including a single flow path. By appropriately varying the relative flow resistance of different flow paths in the applicator, it may be possible to vary the amount, velocity, and / or spread of powder dispensed. For example, without wishing to be bound by theory, in one mode of operation, a smaller coverage area and a higher powder dispensing rate may be achieved by using a lower pressure in the second flow path that bypasses the powder chamber, which may have a relatively high pressure. In another mode of operation, a larger coverage area and a lower powder dispensing rate may be achieved by using a higher pressure in the second flow path compared to the lower pressure in the chamber.

[0047]

[0060] In the above embodiment, a valve 125 is shown disposed in the second flow path that bypasses the chamber 110. However, embodiments are contemplated in which a valve or other flow restriction is disposed in either one or both of the first and second flow paths, as the present disclosure is not limited to how the relative flow resistance between the two flow paths is controlled. Furthermore, it should be understood that the valve or other suitable variable flow resistance may be operated by either manual and / or electrical control, as the present disclosure is not limited to any particular method for controlling the variable flow resistance.

[0048]

[0061] FIG. 6 shows yet another embodiment of a powder applicator 100 similar to that described above. This embodiment includes only one flow path and a chamber 110 having a longitudinal axis that is angled relative to an axis through the applicator's outlet 130 as described above. Additionally, as best seen in FIG. 6, in some embodiments, the downstream opening of the first conduit 122 into the interior of the housing containing the chamber can be radially offset from the opening 132 formed in the chamber while still directing the gas flow toward a distal portion of the chamber located between the opening of the chamber and the proximal end of the chamber opposite the opening. Similarly, the first conduit can also direct the gas flow into a volume surrounding the distal porous portion of the chamber. The opening of the conduit can also be oriented in an angled direction relative to the opening of the chamber and / or the longitudinal axis through the chamber itself. Similarly, this can help prevent the gas flow from exiting the conduit and flowing directly into the opening of the chamber without fluidizing the powder contained within the chamber. In addition to the above, the illustrated embodiment may also be able to provide fine control over the amount and spread of powder dispensed from the applicator, in particular compressing the bellows 120 at a relatively slow rate may allow a larger amount of powder to be dispensed in a more concentrated area compared to a smaller amount of powder dispensed over a larger area when the bellows is compressed at a relatively fast rate.

[0049]

[0062] FIG. 7 shows another embodiment of a powder applicator 100 similar to that of FIGS. 4A-4C. In this embodiment, the applicator 100 is configured to receive a first gas flow from a first pressurized gas source and a second gas flow from a second pressurized gas source separate from the first pressurized gas source. In this embodiment, a first pressurized gas source 120 and a second pressurized gas source 140, which may be gas supplies or canisters as described above, are provided to the applicator 100 at a first gas inlet 121 and a second gas inlet 141. Upon entering the applicator 100, the first gas flow passes through a first gas conduit 122 and through a porous material 112 forming at least a portion of a chamber 110 where the first gas flow fluidizes and entrains powder (not shown) contained within the chamber. The entrained powder then flows through an opening 132 formed in the chamber to a second branch 124. A separate second gas stream flows through the second conduit 142 to the branch 124. At the branch 124, the first gas stream with entrained powder and the second gas stream combine to form a combined gas stream and entrained powder, which then flows through the outlet 130. Similar to the use of variable flow restrictions in any one or both flow paths of the device, the pressurized gas source can be operated to adjust the amount of gas flowing in the various flow paths to adjust how the powder is dispensed from the applicator, as described above. It should be understood that the first and second pressurized gas sources may be configured to operate independently such that no gas can flow, only the first gas stream can flow to the chamber 110, only the second gas stream can flow to the outlet 120, or both the first and second gas streams can flow. However, embodiments are also contemplated in which the first and second pressurized gas sources operate in combination with each other.

[0050]

[0063] 9A and 9B show one embodiment of powder applicator 100 with rotatable handle 150 in different positions. In the configuration of FIG. 9A, handle 150 is oriented vertically relative to chamber 110. In the configuration of FIG. 9B, handle 150 is oriented horizontally relative to chamber 110. As explained above, rotating handle 150 relative to chamber 110 can allow a user to adjust the holding position (e.g., to gain better access to the target delivery site) while maintaining the chamber in an orientation that keeps the powder in contact with the porous portion of the chamber. Although only two different handle positions are shown in FIGS. 9A and 9B, it should be understood that the handle can be configured to rotate to any suitable angle as described above.

[0051]

[0064] 10 illustrates an embodiment of a powder applicator 100 having a rotatable handle 150. In this embodiment, a proximal portion 171 of the applicator is configured to rotate relative to a distal portion 172 of the applicator. The proximal portion 171 includes the bellows 120 (or other suitable source of pressurized gas), the handle 150, and a first portion 175 of a general flow path from the bellows 120 to the outlet 130. The distal portion 172 includes the chamber 110, the outlet 130, and a second portion 176 of a general flow path. The handle 150 (and the remainder of the proximal portion 171) may be configured to rotate about an axis of rotation 151 that is parallel to an axis 152 through the outlet 130. The proximal portion 171 and the distal portion 172 may be rotatably coupled at an interface 170, which may include a sealing component 174, such as a gasket or O-ring, as described in detail above.

[0052]

[0065] Although the handles shown in Figures 9 and 10 are illustrated as being used with an applicator having a chamber at a particular angle and a single flow passage connecting the bellows to the outlet, it should be understood that the illustrated handles may be used with any of the applicator embodiments disclosed herein, as the disclosure is not so limited.

[0053]

[0066] Also shown in FIG. 10 are valves configured to prevent backflow, including a first one-way valve 158 and a second one-way valve 159. As discussed above, the first one-way valve 158 may be configured to allow gas flow from the bellows 120 to the outlet 130, and may be configured to prevent fluid flow from the outlet 130 to the bellows 120. In the embodiment of FIG. 10, the first one-way valve 158 is located immediately downstream of the outlet of the bellows 120. In other embodiments, as discussed above, the first one-way valve may be located in another location, such as proximal to the outlet. The second one-way valve 159 may be configured to allow gas flow from the ambient air surrounding the bellows 120 to the applicator 100, but may be configured to prevent gas flow from the bellows 120 to the ambient air when the bellows 120 is compressed. In the embodiment of FIG. 10, the second one-way valve 159 is located adjacent to the first one-way valve 158 and is angled relative to the first one-way valve 158. However, it should be appreciated that the second one-way valve may be located in a number of suitable locations and in a number of suitable orientations. Further, it should be appreciated that the applicator may include any suitable number of valves (such as first one-way valve 158 and second one-way valve 159), regardless of whether the applicator includes a handle.

[0054]

[0067] 11 illustrates another embodiment of an applicator 100 having a rotatable handle 150. In this embodiment, the handle 150 rotates relative to the outer housing 102 of the applicator 100 while other components of the applicator 100 (e.g., the bellows 120, the chamber 110, and the outlet 130) remain stationary. Thus, the handle 150 may be configured to rotate relative to both the chamber 110 and the bellows 120. The handle 150 may be configured to rotate about a rotation axis 151 that is parallel to an axis 152 that passes through the outlet 130.

[0055]

[0068] 12A and 12B show details of one embodiment of an interface between the handle 150 and the applicator. The handle 150 includes a protrusion 160 configured to be received in any one of a number of recesses 162. While the recess 162 may be associated with any suitable portion of the applicator 100, such as the outer housing 102, in the embodiment of FIG. 12A, the recess 162 is associated with a connector 104 disposed between the bellows 120 and the outer housing 102. As the handle 150 is rotated, the protrusion 160 is biased into one of the recesses 162 such that the handle 150 is locked in discrete angular positions.

[0056]

[0069] Although the handle shown in FIG. 11 is shown as being used with an applicator having a chamber at a particular angle and a single flow passage connecting the bellows to the outlet, it should be understood that the handle shown may be used with any of the applicator embodiments disclosed herein, as the disclosure is not so limited.

[0057]

[0070] FIG. 12B further illustrates a one-way valve, referred to (for consistency with the above description) as second one-way valve 159. Second one-way valve 159 may be configured to allow gas flow from the ambient air surrounding bellows 120 to applicator 100 (e.g., when bellows is expanded) but may be configured to prevent gas flow from bellows 120 to the ambient air (e.g., when bellows is compressed). In the embodiment of FIG. 12B, second one-way valve 159 is disposed between bellows 120 and outer housing 102 and oriented perpendicular to the flow path between bellows 120 and outer housing 102. However, it should be appreciated that in other embodiments, second one-way valve may be in other positions and / or orientations as the disclosure is not limited in this respect. EXAMPLES

[0058]

[0071] Example: Variable Operation of a Powder Applicator

[0072] Figure 8 shows representative diagrams of different powder distribution patterns achievable using a therapeutic powder applicator similar to that shown in Figure 6. The left side shows a broad, diffuse distribution pattern. The right side shows a distribution pattern that is more convergent to a smaller area. These different distributions were obtained by varying the speed at which the applicator bellows is pressed as described above.

[0059]

[0073] Example: Powder flow properties

[0074] Dry powders having Hausner ratios between about 1.08 and 1.39 were characterized and evaluated for flowability. Based on the tests performed, and without wishing to be bound by theory, it was found that a low Basic Flowability Energy (BFE), low Airflow Energy (AE), high Airflow Index (i.e., low cohesiveness due to high sensitivity to airflow), low Wall Friction Angle (WFA) (due to low sliding resistance between the powder and the wall), and low Compressibility Percent are associated with improved powder flowability.

[0060]

[0075] While the present teachings have been described in conjunction with various embodiments and examples, the present teachings are not limited to such embodiments or examples. On the contrary, the present teachings encompass various alternatives, modifications, and equivalents, as will be appreciated by those skilled in the art. Accordingly, the foregoing description and drawings are by way of example only.

Claims

1. a chamber configured to contain a therapeutic powder, at least a distal portion of the chamber including a porous membrane including a plurality of holes; a first source of pressurized gas in fluid communication with the chamber through the plurality of holes in the distal portion of the chamber; an outlet in fluid communication with the chamber; Including, the distal portion of the chamber is disposed adjacent to the outlet; the first pressurized gas source and the chamber are configured such that a first flow of gas from the first pressurized gas source flows around at least a portion of the chamber before entering the plurality of holes in the distal portion of the chamber, entraining the therapeutic powder in the first flow of gas. Therapeutic powder applicator.

2. 2. The therapeutic powder applicator of claim 1, wherein the first pressurized gas source and the chamber are configured to cause the entrained therapeutic powder to flow through the outlet.

3. 3. The therapeutic powder applicator of claim 2, wherein said first pressurized gas source and said outlet are configured such that a second flow of gas from said first pressurized gas source flows through said outlet without flowing through said chamber.

4. 4. The therapeutic powder applicator of claim 3, wherein the relative flow rates of the first and second gas streams are adjustable.

5. 3. The therapeutic powder applicator of claim 2, further comprising a second source of pressurized gas, said second source of pressurized gas and said outlet configured such that a second flow of gas from said second source of pressurized gas flows through said outlet without flowing through said chamber.

6. 10. The therapeutic powder applicator of claim 1, wherein said first source of pressurized gas is a bellows.

7. 10. The therapeutic powder applicator of claim 1, further comprising a handle configured to rotate relative to said chamber, wherein said first source of pressurized gas is configured to rotate with said handle as said handle rotates relative to said chamber.

8. 10. The therapeutic powder applicator of claim 1, further comprising a handle configured to rotate relative to said chamber, said handle configured to rotate relative to said first source of pressurized gas.

9. 7. The therapeutic powder applicator of claim 6, further comprising a first one-way valve configured to prevent backflow into said outlet when said bellows expands.

10. 10. The therapeutic powder applicator of claim 9, further comprising a valve configured to fluidly connect said bellows with an external environment when said bellows expands.

11. a chamber configured to contain a therapeutic powder, at least a distal portion of the chamber including a porous membrane including a plurality of holes; A first gas inlet; an outlet in fluid communication with the chamber; Including, the first gas inlet is in fluid communication with the outlet through the plurality of holes in the distal portion of the chamber; the distal portion of the chamber is disposed adjacent to the outlet; the first gas inlet and the chamber configured such that a first gas flow from the first gas inlet flows around at least a portion of the chamber before entering the plurality of holes in the distal portion of the chamber to entrain the therapeutic powder in the first gas flow.

12. 12. The therapeutic powder applicator of claim 1 or 11, further comprising the therapeutic powder disposed within the chamber.

13. 13. The therapeutic powder applicator of claim 12, wherein said therapeutic powder is a hemostatic powder.

14. 12. The therapeutic powder applicator of claim 11, further comprising a first conduit extending between said first gas inlet and said chamber.

15. 15. The therapeutic powder applicator of claim 14, further comprising a second conduit extending between said first gas inlet and said outlet such that a second gas flow flows through said outlet without flowing through said chamber.

16. 16. The therapeutic powder applicator of claim 15, further comprising a variable flow resistance disposed along said first conduit and / or said second conduit.

17. 15. The therapeutic powder applicator of claim 14, further comprising a second gas inlet, said second gas inlet and said outlet in fluid communication such that a second flow of gas from said second gas inlet flows through said outlet without flowing through said chamber.

18. 12. The therapeutic powder applicator of claim 11, further comprising a bellows in fluid communication with the first gas inlet.

19. 12. The therapeutic powder applicator of claim 1 or 11, wherein a longitudinal axis of the chamber is parallel to an axis through the outlet.

20. 12. The therapeutic powder applicator of claim 1 or 11, wherein a longitudinal axis of the chamber is at an angle to an axis through the outlet.

21. 12. The therapeutic powder applicator of claim 1 or 11, further comprising a handle configured to rotate relative to the chamber.

22. 22. The therapeutic powder applicator of claim 21, wherein the handle is configured to rotate about an axis of rotation parallel to an axis through the outlet.

23. 22. The therapeutic powder applicator of claim 21, wherein the first gas inlet is configured to rotate with the handle when the handle is rotated relative to the chamber.

24. 22. The therapeutic powder applicator of claim 21, wherein the handle is configured to rotate relative to the first gas inlet.

25. 12. The therapeutic powder applicator of claim 11, further comprising a bellows coupled to said first gas inlet, a first one-way valve configured to prevent backflow into said outlet when said bellows expands.

26. 26. The therapeutic powder applicator of claim 25, further comprising a second one-way valve configured to fluidly connect said bellows with an external environment when said bellows expands.

27. a first gas inlet in fluid communication with the outlet through the plurality of holes in the distal portion of the chamber; 2. The therapeutic powder applicator of claim 1, wherein the first gas inlet is disposed adjacent a proximal portion of the chamber.

28. 12. The therapeutic powder applicator of claim 11, wherein the first gas inlet is disposed adjacent a proximal portion of the chamber.

29. 12. The therapeutic powder applicator of claim 1 or 11, wherein the outlet of the chamber is configured to be directed at least partially vertically downward during operation of the applicator such that the therapeutic powder is disposed adjacent the distal portion of the chamber.

Images