Inhaler for analgesic or anaesthetic purposes

2,442,004

May 25, 1948. j. τ. hayward-butt

INHALER FOR ANALGESIC OR ANAESTHETIC PURPOSES

Filed Aug. 17, 1945

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Patented May 25, 1948

2,442,004

UNITED STATES PATENT OFFICE

2,442,004

INHALER FOR ANALGESIC OR ANAESTHETIC PURPOSES

John Terry Hayward-Butt, Bude, North Cornwall, England

Application August 17, 1945, Serial No. 611,107 In Great Britain January 29,1945

Claims.

This invention is for improvements in or relating to inhalers for analgesic or anaesthetic purposes, and has particular reference to inhalers which are small and compact enough to be carried in the pocket and are robust in construction.

Various forms of portable inhalers are already known but these suffer from the disadvantage that the relatively small charge of the volatile inhalant supported on fibrous absorbent material has to be replenished comparatively frequently.

It is an object of the present invention to provide an inhaler for analgesic or anaesthetic purposes which in addition to the properties of lightness, compactness and robustness also possesses the property of having a relatively large capacity so that repeated re-charging at short intervals is unnecessary. Further it is an object of the invention to provide an inhaler which is simple to charge and use, can be stored in charged condition indefinitely and is rendered ready for use instantly.

According to the present invention, there is provided a pocket inhaler for analgesic or anaesthetic purposes which comprises a perforated nose-piece, a chamber containing fibrous absorbent material for the volatile liquid analgesic or anaesthetic substance, one or more air inlets for directing air through the absorbent material and thence to the nose-piece, a container connected with the said chamber adapted to hold a supply of the volatile liquid and means for feeding the liquid to the absorbent material. The charge of volatile liquid may be carried in a frangible ampoule or like sealed container and the apparatus may be provided with means for breaking the ampoule to liberate the liquid.

As in the case of known inhalers air is drawn by the patient through the absorbent material moistened with the liquid and thence through the perforated nosepiece into the lungs.

The apparatus may be used for the administration of a wide variety of volatile analgesic or anaesthetic materials. The apparatus may conveniently be of cylindrical form, the nose-piece, chamber for absorbent and the liquid container or the container for the ampoule may be screwcoupled in series.

The liquid container may be of the unspillable variety so that flooding of the absorbent chamber is prevented and the means for feeding the liquid (Cl. 128—200) to the chamber for the absorbent may conveniently consist of a wick, one end of which is embedded in fibrous absorbent (comprising, e. g., cotton wool, which may be in the form of dental rolls) and the other end of which dips into the liquid. The absorbent may consist of other fibrous material or of a coil of the wick itself. Alternative means for feeding the liquid may embody a device for passing a predetermined volume 10 of liquid to the abosrbent as required.

The end of the liquid container or a cap covering the nose-piece may constitute a measure for the liquid so that over-filling of the container is prevented.

The apparatus is intended to be held in the hand and volatilisation of the liquid is thereby increased. Alternatively, the apparatus may embody a simple form of electric heater.

Means may be provided, e. g., a fingerhole or an 20 adjustable valve for controlling the flow of air through the apparatus and the air inlet, or inlets, may be so arranged that a screw cap over the nose-piece constitutes an air-tight seal.

It will be understood that the absorbent cham25 ber and liquid container may be arranged concentrically.

The whole apparatus may be sufficiently small to be carried in the pocket, e. g., like a pen or like a pencil torch, though it will be understood that 30 parts may vary in relative size, shape and arrangement.

The apparatus may conveniently be made of metal or of synthetic resin or of both and the liquid container may be transparent.

The nose-piece and the rest of the apparatus may if desired be connected by a length of rubber tubing which enables the chambers for the fibrous material and liquid to be fixed, e. g., to the patient’s head, by means of one or more adjust40 able elastic straps. Alternatively, the complete apparatus may be held as above-described and the nose-piece may be connected by rubber tubing to a cap for the patient’s nose.

When the liquid charge is contained in an 45 ampoule this is preferably made of glass or of plastic and the means to liberate the liquid may be such as to break, crush, pierce or otherwise open the ampoule.

The ampoule may conveniently be cylindrical 5Q in shape and may fit snugly within the casing of

2,442,004 the apparatus. It may be held resiliently in place within the casing by means of fibrous material.

Means for breaking the ampoule may consist of a piston moving within the casing and provided with a striking pin or rod passing through the end cap of the apparatus and pressed away from the ampoule by means of a spring of such stiffness that accidental dropping of the apparatus even on the rod fails to drive the piston against the ampoule.

When the apparatus is required for use the end is driven against, a- hard surface so as to force the pin and its piston against the end of the ampoule to break it between the piston and the inner end of the nose-piece unit.

Sufficient absorbent fibrous material is-provided in the container to soak Up the whole of the contents of the ampoule.

Volatilisation of the analgesic or anaesthetic liquid into the air stream is effected by passing air, e. g. from the nose-piece end of the apparatus over a wick wound around the tube attached to the nose-piece and thence through one or more holes or slots into the tube to the nose-piece.

It will be understood, that any one of a number of alternative means may be provided: for breaking,.piercing or ;opening;the: ampoule;: Thus* the: ampoule may be broken by means of. a screw plunger or by; means of a lever operated from outside the: casing* suitable means being: provided to guard against accidental breakage of the. ampoule.

Following is a description by way of example and; withreferencetothe accompanyingdiagrammatic drawing of three forms of inhaler made in accordance with the. present invention.

In the drawing,

Figure 1 shoWspattly in central· section, ah inhaler provided with a supply of volatile analgesic or anaesthetic: liquid in a sealed ampoule.

Figure· 2 shows an alternative form of inhaler, alSo in section in which the liquid is contained in a sealed frangible container broken by means of a scrcw-threadedplunger; arid

Figure 3 shows in section another form Of apparatus in which the iiquid is contalhed in a nonspillable chamber within the casing.

Similar reference fiUffierais denote similar parts throughout the figures of the drawing.

Referring to the three figures* H is a casing which is preferably metal and has- a sCrewihreaded vapOUr-tight nose-cap 12 at one end. A fibse-pi§Ce I ^provided, with nostril-guard 14 projects fTOm the casing 1 i and terminates within the casing in a tubular extension 15 which is slotted or otherwise perforated at 16 arid at its inner end preferably terminates in a solid head I T. The tubular extension IB- is held in position axially in the casing H ^;by.me’ahs-0f locating plates 18 and 19, the. latter being provided with One-or more holes for the admission of air to the annular space between the casing I (and the tubular extension 15* ’ihe-tUbUlar extension 15; is wound with a wick: of fibrous liquid absorbent material 20. ReferriiigtoFlgufel, the volatile liquid 21 is held in a sealed frangible ampoule 22 and is held in position in the casing between plugs of fibrous material 23 and 24. That end of the casing remote froth the nose-piece is closed by means of a screw cap 25 provided with a central hole 26 through Which a pin :27 of a piston 28 passes. This pistbn is held away from thO ampoule 22 by means of. a spring 29 which, bears against the abutmeht_3ft andis.of.such stiffness that even if the apparatus falls to the ground on the pin 27 the ampoule is not broken.

The inhaler is operated by holding it in the hand and driving the pin 27 against a hard surface to break the ampoule 22 and liberate the liquid 21 which saturates the fibrous material 23 and 24 and the wick 20. The cap 12 is now withdrawn and the nose-piece 13 inserted in the nostril. Air is aspirated through the perforated plate 19 over the wick 20 through the slot 16 and thence to the nose-piece. Vaporisation of the volatile liquid is assisted by the warmth of the hand.

Referring to Figure 2, a frangible ampoule 33 is held loosely in position by inwardly-extending projections 34.and.by a screwthreaded plunger 35. The. end, face of the plunger 35 remote from the ampoule is grooved, as at 36, for rotation of the plunger, e. g;, by means of a coin or by means of a. flange 37 attached to the end of the screw cap 3 3 for the purpose of breaking the ampoule and liberating the liquid.

Referring to Figure 3, the casing 11 is divided as in Figure 2 by a transverse wall 31 provided with an axially-projecting tube 32 and wick 20. The chamber 39 is charged with volatile liquid through the screwed-on cap, 40; the* amount of liquid being such that liquid, does- not, flow directly through the tube 32. In this-case, the apparatus is instantly ready for use as long as any liquid remains in it and requires only the. removal of the nose-cap and insertion in the nostril.