GB2054381A

GB2054381A - Infusion device

Info

Publication number: GB2054381A
Application number: GB8018989A
Authority: GB
Original assignee: Unisearch Ltd
Current assignee: Unisearch Ltd
Priority date: 1979-06-11
Filing date: 1980-06-10
Publication date: 1981-02-18
Also published as: DE3021686A1; AU5924380A; JPS5649161A; GB2054381B; CH636272A5

Abstract

An infusion device suitable for subcutaneously or intravenously supplying medication, and which is lightweight and readily portable, comprises a container 1 for a sachet containing liquid medication which is collapsible within the container under the action of mechanical means. In the Figure, the sachet (not shown) is collapsed by a coil spring 2 acting on a lever 3', 3'', and is positioned under the lever arm 3''. The lever arm 3' moves across a window (not shown) to indicate the amount of liquid medication left in the sachet. The contents of the sachet are dispensed through outlet nozzle 5. <IMAGE>

Description

SPECIFICATION Infusion device The present invention relates to infusion devices and more particularly to medical infusion devices for supplying metered amounts of a liquid medication over a prolonged period of time.

Infusion devices are known but prior art construc tions have been bulky and inconvenient and have required electrical power supplies, usually in the form of a battery, to a motor drive. It is an object of the present invention to provide an infusion device which can be made small enough to be convenient for the user which in the case of a medical patient may be a child, to carry or wear for extended periods. In this regard the present invention is appl icable to use in the treatment of endocrine disorders such as diabetes, where daily injections of insulin are the normal means of treatment; or for, say, opi ate infusion to terminal cancer patients.

In one form the present invention provides an infusion device comprising, a housing for containing a renewable collapsible liquid containing sachet, reloadable mechanical means operable to collapse said liquid containing sachet when in situ, and outlet means for delivery of the liquid contents of the sac het when acted upon by the mechanical means.

The reloadable mechanical means preferably takes the form of a spring force or gas pressure whereby when a sachet containing, say, a day's sup ply of medication is fitted it is slowly squeezed to deliverthe medication via a hypodermic fitting. The supply rate may be controlled by a porous metering nozzle under constant pressure or by a mechanism driven at a constant rate.

Embodiments of apparatus of the invention will now be described by way of example with reference to the accompanying drawings, in which:~ Fig. 1 is a view of a first embodiment of an infuser in accordance with the invention; Fig. 2 is a cut-away view showing the inner work ings of the device of Fig. 1; Fig. 3 is a view Ill-Ill of the device of Fig. 1; Fig. 4 is a view of a second embodiment; Fig. 5 is the view V-V of the Fig. 4 embodiment; Fig. 6 is an enlarged cut-away view of the embod iment of Fig. 4; and Fig. 7 is an external view of a third embodiment in accordance with the invention; and Fig. 8 is a cut-away view of the embodiment of Fig.

7 to an enlarged scale.

In the embodiments shown there are two spring force operated infusers (Figs. 1-6) and one gas pressure operated infuser (Figs. 7, 8).

The infuser of Figs. 1-3 comprises a housing 1 containing a resettable coil spring 2 acting upon one end of a pivoting lever 3. There is a window 4 provided in the housing 1 which displays calibrated settings denoting the extent of the supply of medication remaining to be dispensed at any time during its operation. The amount of remaining supply being denoted by the position of the lever arm 3' as it passes across the window 4, during collapsing of a sachet (not shown) positioned underthe lever arm 3".

The contents of the sachet being dispensed via outlet nozzle 5.

In Figs. 4-6 like numerals indicate like components as per the embodiment of Figs. 1-3. It will be noted that in this case the spring 2 acts directly upon the exterior of the sachet 7. In this embodiment the spring 2 is fitted with a locking device or tab 8 so that the infuser can be loaded and stored ready for use which is accomplished by unlocking the tabs 8 from their complementary recesses 9 in the housing.

Figs. 7 and 8 show an embodiment of a gas pressure operated infuser comprised of a housing 1 and a tube 9 for containing a collapsible sachet and a containment volume 1' to be filled with gas under pressure which acts upon the sachet to expel its contents through nozzle 5. The containment volume is pressurized, when the sachet has been fitted, via an inlet valve 10. The volume can only be pressurized to a predetermined level as pressure control valve 11 operates at that predetermined pressure. If, at any time, it is desired to disconnect the infuser the gas pressure within may be released by operating relief valve 12.

Metering of the outflow of medication in all these embodiments may be provided by a porous metering membrane or other porous medium located within the outlet nozzle or by an additional metering device remote from the infuser.

The porous nozzle may be either a part of the sachet or part of the infuser, to be thrown away after a day's use or re-used, respectively. Where the sachet is provided already loaded with a sterile medication and complete with its own nozzle and a fitting to attach directly to a hypodermic tube, the complete sachet may be disposed of and replaced by a fresh sachet complete with its own metering membrane when the first sachet has been emptied.

It will be appreciated that the foregoing embodiments which describe the present invention in relation to medical application are not to be limiting upon the broadest form of the invention which is applicable to other fields as will be appreciated by the addressee.

Claims

1. An infusion device comprising, a housing for containing a renewable collapsible liquid containing sachet, reloadable mechanical means operable to collapse said liquid containing sachet when in situ, and outlet means for delivery of the liquid contents of the sachet when acted upon by the mechanical means.

2. An infusion device as claimed in claim 1, wherein the reloadable mechanical means comprises a spring.

3. An infusion device as claimed in claim 2 further comprising lever spring, which lever means are operated by the spring to apply collapsing force to a sachet when in situ.

4. An infusion device as claimed in claim 2 wherein the housing is a tubular member having a coil spring located therein, means protruding from the housing to compress the spring and retain it in its compressed condition ready for release when a sachet has been fitted.

5. An infusion device as claimed in claim 1 wherein the reloadable mechanical means comprises a rechargable gas pressure cylinder within the housing or a replaceable pressure cylinder adapted to be fitted in the housing.

6. An infusion device as claimed in any one of the preceding claims comprising a metering nozzle for controlling the outflow from the sachet when in use.

7. An infusion device substantially as herein before described with reference to the accompanying drawings.