INHALATION DEVICE

Abstract: An inhalation device, comprising an inhalation chamber (1) fitted with an inlet duct (2) and a mouthpiece (3), the former receiving a spray (6) containing a substance to be inhaled. Said inhalation chamber (1) is substantially in the shape of one or several balls, flattened balls, ellipses or polygons.

Description: inhalation device The present invention relates to an inhalation device provided with an inhalation chamber and an inlet duct as well as a mouthpiece for receiving a spray which contains a substance to be inhaled. The most common form of medicine used in inhalation therapy is an inhalation aerosol. This is an effective form of medicine if used properly, but the correct use is difficult to learn for many patients. It is known that only a small share (circa 10 %) of the medicine reaches the lungs and most of the medicine remains in the mouth, with an added risk of side effects. It has also been stated that less than 20% of the aerosol propellant is gasified upon leaving the nozzle and that the gasification of the propellant takes several seconds. Various inhalation chambers,into which the aerosol dose is sprayed before, inhalation, have been developed in order to overcome the above drawbacks. When sprayed into such, a chambsϊ ' , the propellant droplets have sufficient time to gasify, whereby the medicament particles can be inhaled later. It has been shown that the amount of medicament remaining in mouth and throat is considerably decreasing by using a device with an inhalation chamber but the clinical effect of such a device is not better than a plain inhalation aerosol, if properly used. However, the presently available inhalation chambers are quite bulky, generally about 500 - 750 ml in capacity, and thus uncomfortable to use carry along. Finnish Patent publication 64512 (Draco A3, Sweden) discloses an inhalation device whose inhalation chamber is designed to .conform with the conical shape of an aerosol spray generated from an injection nozzle. The size of the chamber is 500 - 2000 ml. The conical form of the chamber does not «-. improve or support the rotational movement of the aerosol spray in the chamber. An object of the present invention is to provide an inhalation device, wherein an aerosol spray is set in rotating motion in the inhalation chamber thus improving the gasification of the propellant and liberation of the medicinal particles from the propellant. A device of the invention is characterized in that the cross- section of inhalation chamber (1) in a plane of the same direction as the a.erosol spray substantially the shape of a circle, ellipse, polygon or a combination or interlinked arrays thereof to ac iev a rotational movement of said spray and that said chamber (1 ) can be flattened at least in one of its lateral directions. In this inventio the form of the chamber is chosen to .build up a rotational movement of the aerosol spray. With this new functional principle a more efficient inhalator but smaller in. size is obtained. The efficiency is improved with the same or even lower doses of medical aerosol preparations. The other features of the invention are set forth in the annexed claims. The function of this new device was studied by photographing the behaviour of a spray sprayed into a round glass bottle (250 ml) (exposure time of 1/.1000 seconds). The turbulence was formed right after the triggering action and its fastest speed was circa 60 r/sec in the ball with a 4 cm radius. " It was also observed that ungasified propellant drops swirled along with the turbulence and gasified-while doing so. The turbulence continued for 3-4 minutes during which the propellant gasified almost completly. The construction of a device of the invention was optimized and compared with prior devices by measuring the amount of medicine that could be inhaled. Thus, a dose injected into the chamber was sucked 3 seconds after the triggering action into a particle separator (Andersen 1 AFTM Cascade Impactor) and the thus separated amounts of medicine having different particle sizes were analyzed chromatographically. Each result is the average of 40 sprays. Reference articles were commercially available inhalation chambers: Volu atic R , webulator R , Inspri- Ξase s , Inhal-Aid . A device of the invention having the optimal size and shape provided a result at least twice as good as any of the above- mentioned devices when using the same aerosol (Salbubent l ) . The size of such optimal device was smaller than any of the above-mentioned devices. The most efficient device proved to be a device with a spherical or spherically compressed inhalation chamber, If the form of the inhalation chamber deviated from a sphere., the rotation velocity and duration decreased as well as the amount of inhalable medicine. If in an ellipsoidal camber the shortes diameter was less than 3Q% of the longest diameter an efficient rotation was not obtained. In a spherical chamber the rotational movement was easily obtained by spraying into the chamber in a non-radial direction, i.e. with a slight deviation from the center of the sphere. With increasing deviation (over 10°) the turbulence is slowing down and the inhable product decreases. The best result was obtained when mouthpiece was on the side wall of the chamber perpendi¬ cular to the rotational plane of the aerosol spray. The poorest result was obtained when the mouthpiece was on the periphery of the rotation but even then the result were better than the result obtained by the prior art devices. Satisfactory result were also obtained when the inhalation chamber was made of two or more spheres or spherelike chambers interconnected. The direction and plane of the rotation are depending on how the axle of the spray is directed to the center of the chamber. The operation of a device of the invention is very easy. It can be used the same way as a regular inhalation aerosol, whereby a patient places the mouthpiece in his or her mouth and triggers a dose at the start of inhalation. If this is awkward, a patient can first trigger a dose and then inhale after a while; the device functions just as effectively. If a one-way valve is employed, the device will be particularly suitable for children and elderly persons who have most deficiencies in aspiration technique. In this case, it is not possible to exhale through the device, only inhalation is possible. The invention will now be described in more detail with reference made to the accompanying drawings, in which figs. 1 - 3 illustrate a fet-r basic embodiments of the chamber of a device of the invention, figs. 4 - 5 show in cross-section three * embodiments of the invention, and figs. 7 - 12 show still further embodiments of the invention. A few examples of the chamber dasings in a device of the invention are illustrated in figs. 1 - 3. Fig. 1 illustrates perpendicular section planes of the device in view of the aerosol spray and fig. 2 shows the corresponding examples of chamber outlines obtained by these planes. From the user's point of view it is preferable that the optimal configuration was found to be a distinctly laterally flattened shape (fig. 2), whereby the device can be designed narrow and readily portable. The structures of an aerosol container or a completed inhalation aerosol as well as those of a supply duct, mouthpiece and an eventual one-way valve can be re¬ solved in several ways (figs. 4 - 10). A medicine- containing aerosol aerosol container can be fitted to the device as an integral part thereof (figs. 4, 5, 6 and 10) or the device can be provided with a separate inhalation aerosol with its plastic casing (figs. 7 9), The supply or inlet duct and the mouthpiece can be made of one and the same tube (figs. 4 and 10) or they can be separate components (figs. 5, S and 7 - 9). In this case, the position of a mouthpiece must be experimentally optimized as its position has an effect on the operation of the device depending on the chamber configuration, volume and gas dosage. Figs. 11 and 12 illustrate an embodiment consisting of three combined spherical chambers. It is obvious that the chambers can be different chape and their number can be different from what is illustrated. ' The purpose of figs. 11 and 12 is to demonstrate that the invention relates also to linked inhalation chambers. As pointed out above, figs. 1 - 3 illustrate a few basic embodiemtns of an inhalation chamber. Fig. 1 shows the cross-sectional planes described in figs. 2 and 3. In principle, a chamber of the invention comprises a spherical and flattened chamber but, as shown in fig. 3, the chamber configuration can nevertheless be other than circular. The chamber outline can be circular, elliptical, polygonal or a combination of all these. The cross-section of an inhalation chamber shown in fig. 2 can also vary; its shape is not critical for the invention. The shape can be an elliptical, polygonal, rectangular or various combinations thereof. Fig. 4 illustrates an embodiment, wherein an inhalation chamber 1 of circular cross-section is provided with a mouthpiece 3 which also serves as an inlet duct for a medicament sprayed from an aerosol container β. Thus, the duct of mouthpiece 3 is fitted with a socket 7 and its associated nozzle 9 for receiving an aerosol container valve stem 3. Thus, above said mouthpiece 3 is mounted a holder 2 for the aerosol container. Alongside said holder socket 2 is fitted a one-way valve 10 whereby air can flow into the inhalation chamber during inhalation. Both holder; 2 and mouthpiece 3 are also fitted with protective plugs for preventing contamination.- The solution of fig. 5 corresponds to that of fig. 4 with a difference that mouthpiece 3 and inlet duct 2 are separated from each other. Fig. 6 discloses an embodiment which corresponds to that of fig. 4 but also in this case mouthpiece 3 and inlet duct 2 are separated from each other. The. embodiment of fig. 6 differs from that of fig. 5 in the way a one-way valve 10 is positioned and the duct of mouthpiece 3 is designed. A device shown in figs. 7 — 9 comprises a flattened spherical chamber 1. The opposite chamber walls 11 are flat or slightly convex surfaces, with an peripheral surface T therebetween. The cross-section of such envelope surface can be circular, eliptical or the like. The essential point is that a medicament spray is set in a turbulent or rotating motion in the chamber. Projecting from said peripheral surface ■ -1 of the chamber is an inlet or supply duct 2, designed so as to be readily fitted with a meterin-g sprayer. Also project- ing from ball 1 is a mouthpiece 3, fitted with a oneway valve 4. Said valve 4 only opens during inhalation. During exhalation, one-way valve 4 is shut off and-air discharges through a hole 5. The imaginary axes of inlet duct 2 and mouthpiece 3 form a 90o angle relative to each -other. The device is operated as follows. The patient connects a metering sprayer to inlet duct 2, places mouthpiece 3 between his or her lips and triggers a dose of aerosol into chamber 1. The patient performs exhalation through mouthpiece 3, said one-way valve 4 being shut off to prevent exhalation air from passing into chamber 1. Exhalation air discharges through a hole 5 in mouthpiece 3. The patient performs a deep, slow inhalation, whereby oneway valve 4 opens and the medicament particles float¬ ing in the chamber are entrained and carried by inha¬ lation air into the patient's lungs. Thus, the i ha- - lation of a medicament is automatically synchronized .with an inhalation step. A -device shown in fi.g. 10 comprises a flattened, spher¬ ical chamber 1 , out of whose envelope surface 1 extends a mouthpiece 3. This mouthpiece is provided with a socket 7, intended for an aerosol container 6 containing a medicament to be inhaled and fitted at the bottom thereof with a nozzle 9, the latter receiving a container valve stem 8 and opening towards the chamber. Said mouthpiece 3 is also fitted with a one-way valve 4 and a hole 5. The chamber bottom is provided with another one-way valve 10, wherethrough the air required by inhalation flows into the chamber. The device of fig. 10 is operated the same way as that of fig. 7 except that the device is' now fitted with a mere aerosol can. Figs. 11 and 12 illustrate a device whose chamber con¬ sists of three interlinked spherical sub-chambers. Fig. 11 shows the device in side view and fig. 12 shows the same device in plan view. The chamber includes also an inlet duct 2, designed to be readily fitted- with a metering sprayer (shown with dash-and-dot lines in fig. 11). mouthpiece 3 is mounted on the end of chamber 1 opposite from inlet duct 2. The imagenary axes of mouthpiece 3 and inlet duct 2 form a 90° angle relative to each other. The device is operated as follows. The patient connects a metering sprayer to inlet duct 2, performs a deep exhalation, places mouthpiece 3 between his or her lips, triggers aerosol and performs a deep inhalation. The mouthpiece of such a device can be fitted with a one-way valve,, if necessary, in which case there is no need for synchronization between aerosol release and inhalation. As pointed out above, the final shape and linkage of interlinked inhalation chambers may vary within the scope of the invention, regarding the shape, size and number of individual sub-chambers. Only as an example, figs. 11 and 12 illustrate three interlinked balls.

Claims: Claims 1. An inhalation device, comprising an inhalation chamber (1) fitted with an inlet duct (2) receiving a spray (o) which contains a substance to be inhaled, as well as a mouthpiece (3), c h a r a c t e r i z e d in that the cross-section of inhalation chamber (1) in a plane of the same direction as the aerosol spray substantially the shape of a circle, ellipse, polygon or a combination or interlinked arrays thereof to achiev a rotational movement of said spray and that said chamber (1 ) can be flattened at least in one of its lateral directions. 2. A device as set forth in claim 1, c h a r a c t e r i¬ z e d in that the chamber is in the shape of a flattened ball or ellipse. 3. A device as , set forth in claim 2, c h a r a c t e r i ¬ z e d in that the opposite side walls (11) of the chamber are flat or convex and a peripheral surface (1) therebetween forms a chamber outline substantially in the shape of a circle, ellipse, polygon or a combination thereof. 4. A device as set forth in claim 1 , 2 or 3, σ h a τ a c- t e r i z e d in that from the peripheral wall (1 ) of the chamber extend an inlet duct (2). and a mouthpiece (3) . 5. A device as ' set forth in claim 1, 2, 3 or 4, c h a r a c¬ t e r i z e d in that said inlet duct (2) and mouthpiece (3) are an integral component in the envelope (1) of said chamber. " 6. A device as set forth in claim 5, c h a r a c t e r i¬ z e d in that said inlet duct (2) and mouthpiece (3) build separate channels in a common component. 7. A device as set forth in claim 5, c h a r a c t e r i¬ z e d in that the mouthpiece is mounted alongside the chamber. 3. A device as set forth in claim 5, c h a r a c t e r i¬ z d in that the mouthpiece is fitted below the inlet duct. 9- A device as set forth in claims 4 and 5, c h a r a c- t e r i z e d in that the inlet duct is provided with a one-way valve. 10. A device as set forth in claims 4 and 5, c h a r a c- t e r i z e d in that the mouthpiece is provided with a one-way valve.

Inventors: LANKINEN TAPIO, LEHTINEN MATTI JARMO KALEVI, LANKINEN, TAPIO, LEHTINEN, MATTI, JARMO, KALEVI
Applicants: HUHTAMAEKI OY
Application year: 1987
Main classification: A61M15
IPC codes: A61M11, A61M15, A61M16