GB2412325A

GB2412325A - A portable spacer for use with inhalers

Info

Publication number: GB2412325A
Application number: GB0406655A
Authority: GB
Inventors: Galal Eldin Ibrahim Fahmy; Joan Fahmy
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-03-24
Filing date: 2004-03-24
Publication date: 2005-09-28
Anticipated expiration: 2024-03-24
Also published as: GB2412325B; GB0406655D0

Abstract

A device comprises two telescoping tubes 1,2 each having at least one perforation 9 therein, and a sleeve 8 mounted on the tubes 1,2 and surrounding the perforations 9. A valve 15 has two operable positions, in the first position it allows the patient to blow into the spacer, in the second position it allows the patient to inhale from the spacer. When in use a inhaler and mouthpiece are attached to each end, the patient blows into the spacer and activates the inhaler at the same time. The turbulence mixes the air and medicine. The patient then inhales this mix. Such a device constitutes a portable, collapsible spacer suitable for use with inhalers, intended in particular for the treatment of asthmatics.

Description

241 2325

A PORTABLE SPACER FOR USE WITH INHALERS

Field of the Invention

This invention relates to a portable spacer for use with inhalers, intended in particular for the treatment of sufferers of asthma who have breathing difficulties.

Background of the Invention

Asthma is a condition which by nature indicates breathing difficulties, and these are characterized by fluctuating courses of reversible bronchial obstruction of varying severity. There are a number of drugs currently available to prevent these attacks, the majority of which are administered via an inhaler. Normally, the patient's own inspiratory flow is sufficient to draw the medication to the target area in his bronchial tree, with a single breath from the inhaler. When the airway obstruction increases, the patient's inspiratory flow may be insufficient to draw the inhaled medication to the airway target in a single breath. Spacers are used to trap the medication in a fixed volume of air, so that the patient may take his dose over several inhalations rather than in a single breath.

A number of spacers are currently commercially available, all of which have disadvantages. Primarily, they are often bulky devices, often up to 300 mm in length.

They are therefore impractical for the patient to carry with them at all times. Secondly, they typically give no indicator to the user that the dose has been used up. They may also occasionally contain gaps which allow the medication to escape, resulting in a reduced and inaccurate dose. In addition, they may have a poor dosage output, e.g. 15-30.

Summary of the Invention

According to the present invention, a telescopic spacer with a collapsible sleeve provides a portable means of treating sufferers of asthma with additional compromised breathing. The device comprises a telescopic, perforated, substantially tubular body, enclosed in a sleeve, which can be inflated to provide a volume of air in which the medication may be trapped. By being telescopic and fitted with a collapsible sleeve, it can reduce to the dimensions of a standard MD inhaler, to make it easily portable and packaged with the inhaler in the same box. Further, providing a sleeve with an elastic recoil helps complete the clearance of the aerosol from the spacer, as opposed to the passivity of the rigid walls of current spacers. A study along the lines used by Berg, Madsen & Bisgaard, Europ. Resp. J., 98:12, may even provide delivery comparable with that of a nebuliser.

In a preferred embodiment, closure of shoulder slots on the outer tube isolates the spacer volume (tubes and sleeve). This, together with enclosure of a canister and an actuator within a second sleeve creates an airtight space. The patient's continued breathing will result in the patient's inspiration emptying the spacer space through a unidirectional valve until the collapse of the sleeve, indicating full delivery of the dose.

High dose output can be achieved. This is the result of the elastic recoil of the sleeve and the intra-device turbulence created by the opposed firing and exhaling which has the effect of knocking out large particles.

Another feature of this invention is a novel mouthpiece which comprises two channels, one to provide means to inflate the sleeve during the priming expiration, and another to provide means for deflating it during inspiration by inhalation of its contents. During expiration, expired air may pass through the first channel into the tubular body of the spacer during priming of the device only, or subsequently, during regular use, expired air may pass through a valved hole into the atmosphere.

Brief Description of the Drawings

The accompanying drawings illustrate the invention. In the drawings: Figure 1 shows a fully extended spacer comprising telescopic tubes and attached sleeve, without mouthpiece or inhaler attached, in longitudinal section, and more detailed views of a locking mechanism for the tubes and a retaining means for the sleeve; Figures 2 and 3 respectively show the outer tube and inner tube as illustrated in figure 1, in various views; Figure 4 illustrates the mouthpiece, in various views; and Figure 5 illustrates a second sleeve enclosing a canister and an actuator of an inhaler.

Description of the Invention

The invention will now be described by way of example only, with reference to the drawings. The novel spacer, as shown in Fig. 1, comprises two perforated tubes, so designed as to enable one tube to slide within the other.

As illustrated in Fig. 2, the outer tube 1 includes opposed ridges 3 on its internal surface, whilst the inner tube 2 illustrated in Fig. 3 includes corresponding opposed channels 4 on its outer surface. This construction prevents the tubes from rotating with respect to each other.

When not in use, the tubes may be fully contracted, e.g. to a length of 115 mm. By way of example, the device has a diameter of 45 mm. When required for use, the spacer may be extended in a telescopic manner and, when fully extended, the ridges of the outer tube become aligned with two recesses 5 from the channels on the inner tube. By rotating one tube with respect to the other, the ridges are relocated from the longitudinal channels, into the recesses, thereby locking the tubes together and providing a rigid spine in the spacer.

On the outer face, towards each end of the fully extended tubes, continuous circumferential grooves 6 are located. These are designed to each accept a single constraining means, such as a rubber ring 7, used to mount a sleeve 8, which surrounds the perforations 9. The perforations in one embodiment of the device have a diameter of 6 mm.

The sleeve is typically made of neoprene. Neoprene is chosen for the sleeve due to its long history of use in anaesthesia without causing allergies.

The sleeve is flexible and can be fully inflated prior to use, thus providing a larger volume of air in which the medicament may be trapped. The sleeve starts inflating at low pressure (0.1 cm of water) and continues to inflate to a pressure of 45 cm of water, reaching four times its normal size. When not in use, the sleeve is collapsed in a concertina fashion and may be taken off for washing occasionally. The perforations 9 in the tubes allow the free mixing of air and medication with the sleeve so that together they constitute the spacer volume.

The inner tube has a free end 10 on which a standard inhaler can be mounted, although this can be modified to suit other conformations. A mouthpiece may be mounted on the opposite end 11. Fig. 4 illustrates a mouthpiece 12 that may be releasably secured with retaining clips 13 to the free end 11 of the outer tube. The mouthpiece may be connected to the outer tube via a cordage 14, allowing the mouthpiece to be removed from the tube to reduce the length of the spacer, and ensure it is not lost.

The mouthpiece may contain central a one-way or non- return valve 15, e.g. of conventional type. During expiration, the valve disc rests on the shoulders of the central hole, preventing air from entering the spacer volume. During inspiration, the negative pressure created in the mouthpiece, assisted by the elastic recoil of the sleeve, allows the valve disc to move away from the shoulders until it comes into contact with four spaced pegs. Air and medication then flow through the gap around the disc and between the pegs, from the spacer to the patient's mouth.

Further, the mouthpiece may comprise means for optionally routing the air expired by the user into the device via two holes 16 located at the end of the outer tube and corresponding holes 17 on the mouthpiece. The mouthpiece further comprises two outlet holes 18 on the side of the mouthpiece. By routing expired air into the device at the stage of priming, the sleeve may be inflated.

This route may be selected by rotating the mouthpiece, thereby aligning the two holes 16 located at the end of the outer tube and corresponding holes 17 on the mouthpiece, as shown in Fig. 4b. Arrows 19 indicate the direction of the flow of air. When these holes are not aligned, expired air will pass through the outlet holes 18, into the atmosphere.

This is shown in Fig. 4d, wherein the arrows 19 again indicate the direction of the flow of air. In each of Figs. 4b and 4d, an arrow 20 shows the flow of air during inhalation, passing back through the one-way valve 15.

These air routes may be termed "use", indicating that the sleeve may be inflated by expiration, and "expel", whereby expired air may be expelled from the device. Furthermore, the mouthpiece may comprise means for informing the user of which route is being used, such as colour coding it green for use, red for expel, as well as an audible click when the holes are in alignment.

The holes 18 may be provided at an end having two skins or layers each having exactly corresponding holes 18a and lab. Between the skins is a single circular disc 21 which will move with air movement. Tapering pegs 22, four in number and set at the periphery, and fitting into cut- outs in the disc, will prevent disc closing external hole 18b during expiration, whilst negative pressure and disc weight will close internal hole 18a during inspiration.

The cut-outs stabilise disc in space between skins. Viewed from top (end on) the disc will look like a ring (or a washer); in profile it will look like current central one way valve. This arrangement allows air to escape during expiration and prevents air entry into device during inspiration.

By a process of inflating the sleeve, via expiration, and simultaneously spraying the medicament into the spacer, the subsequent air turbulence encourages thorough mixing throughout the spacer. Furthermore, if the mouthpiece is then rotated to the "expel" position, it follows that when the sleeve becomes fully deflated, this may indicate that the dose has been completed.

Although this invention is of particular use to asthma sufferers, it also has a number of other applications, for example, the administration of vaccines or therapies such as the influenza therapy Zanamavir.

A typical method of use for the device comprises the following steps: i) The telescopic tubes are extended to their full length, and rotated to lock in position.

ii) The canister and mouthpiece are attached to each end with the mouthpiece in the red, "exp" position. The patient closes his mouth on the mouthpiece, maintaining this throughout subsequent normal breathing. The patient holds the back of the spacer with the attached inhaler in one hand whilst the other hand holds the mouthpiece and outer tube.

iii) The patient presses the inhaler canister and expires "blows into spacer". The turbulence created by both simultaneous actions ensures a thorough mixing of air and medicine as the expired air flows through the open holes 16 and 17 from the mouthpiece into spacer volume, to collide with the inhaler aerosol. This collision may knock out the larger aerosol particles.

iv) The mouthpiece is then rotated to the "use" position, to close off holes 16 and 17 and the patient continues to breathe normally. In this position, inspiration assisted by the elastic recoil of the sleeve will empty the spacer through the central unidirectional valve. Whilst the expired air is routed through hole 18 into the atmosphere.

Complete delivery is indicated by the sleeve collapse.

v) The mouthpiece and canister are removed, and the spacer is collapsed.

Claims

1. A device comprising two telescoping tubes each having at least one perforation therein, and a sleeve mounted on the tubes and surrounding the perforations.

2. A device according to claim 1, wherein the tubes are lockable into the extended position.

3. A device according to claim 1 or claim 2, wherein the sleeve is mounted in circumferential grooves towards each end of the device and held in the grooves by constraining means.

4. A device according to any preceding claim, wherein the tubes respectively comprise means for attaching an inhaler at one end of the device and a mouthpiece at the other.

5. A device according to claim 4, which additionally comprises a mouthpiece mounted on one of the tubes.

6. A device according to claim 5, wherein the mouthpiece comprises one or more one-way valves and means for routing air expired by the user either into the device or through outlet holes in the mouthpiece.

7. A device according to claim 6, wherein the mouthpiece comprises a number of holes and the tube on which it is mounted comprises a corresponding number of holes.

8. A device according to claim 7, wherein the mouthpiece may be rotated with respect to the tubes to bring the corresponding holes either into or out of alignment, thereby routing the expired air into the device or through the outlet holes respectively.

9. A device according to claim 8, including means to indicate which route is selected.

10. A device according to any preceding claim, additionally comprising a canister and an actuator, and also a second sleeve enclosing the junction of or path between the canister and the actuator.