GB2239804A - External catheter - Google Patents

Abstract

An external catheter for use by mobile men. The catheter comprises a bag (1) of natural rubber latex and contains absorbent material (2). The bag entrance is provided with a stiffening ring (5) a non-return valve (11) and sealing means (30). The bag is provided with at least one pleat (20) to facilitate easy packing. <IMAGE>

Description

EXTERNAL CATHETER This invention relates to external catheters primarily but not exclusively for use while travelling in a sitting position.

Drivers of vehicles may also become more hazardous as they concentrate more on finding a place to relieve themselves rather than on driving.

Many major roads are heavily congested and hence journey times can be significantly extended. Furthermore, recently constructed roads are often ill-equipped with service stations. Many vehicle users are accordingly caused considerable discomfort and distress by the lack of toilet facilities.

US 4 890 834 describes an external catheter comprising a bag.

of flexible water impermeable material. The bag is provided with an entrance having a stiffening ring and containing an absorbent material. The catheter is really only suitable for use within institutions and by bed ridden patients. The device is intended for long term use and hence is complex and expensive. Its use in public would be offensive and the used bag is liable to leak if roughly handled. The device is also difficult to pack compactly. According to the invention there is provided an external catheter comprising a bag of flexible water impermeable material the bag being provided with an entrance having a stiffening ring and containing a sorbent material and fitted with a valve for preventing escape of non-gaseous matter contained in the bag, the bag being opaque, and with one or more pleats.

An embodiment of the invention will be illustrated by reference to the accompanying figures of which Figure 1 is a side elevation cross-section of a bag of the invention for use by males, Figure 2 is a partial end view, of a further embodiment, and, Figure 3 is a top plan view.

The bag comprises a pouch or bag 1. Bag 1 is generally made of thin gauge rubber or plastics material. It is preferred that the bag comprise a natural rubber latex material. In this case the bag walls will generally be less than 0.5 mm thick, preferably less than 0.25 mm thick, preferably more than 50 um but less than 0.1 mm thick. Very thick bags can be rather bulky and expensive. Very thin bags can be rather fragile. The material should not be permeable to aqueous saline solutions and should have a degree of resistance to abrasion and puncture. In other preferred embodiments the catheter comprises paper or card which can be rendered waterproof for example by wax or plastics coating. In view of the short time in which the article contains liquid adequate performance is obtainable.Preferably the bag 1 is not rigid; the reason for this feature will be explained hereinafter. In plan view pouch 1 is preferably generally triangular or quadrilateral with two short edges generally parallel. Rectangular sections, especially those which are elongate are also preferred. Other shapes are also usable.

Bag 1 preferably has an effective volume in the range of about 250 cm3 to about 1000 cm3 more preferably about 500cm3 to about 750cm3. By effective volume the volume of the pouch which can under normal usage contain liquid without spillage is meant. Larger sizes may be used but unit cost may increase and the extra volume may not be utilised.

Furthermore large sized articles may be more noticeable thereby embarrassing the user. Smaller sized articles may also be used but more than one may be required for complete evacuation of the bladder of the user thereby increasing cost.

Bag 1 includes sorbent material 2. As is known salts can significantly reduce the sorbitive properties of many materials. Accordingly materials capable of retaining significant amounts of urine are preferred. Those skilled in the art will readily be able to select such materials which may include the so-called 'super-slurpers' used in diapers and sulphonated 'polyhipes'. Superslurpers are described in Chem Week 21 (July 24, 1974). Sulphonated 'polyhipes' are described in EP 105 634. Other suitable absorbents are cross-linked carboxymethylcellulose (especially CLD ex Buckeye Cellulose Corp, hydrolysed polyacrylonitrile grafted starch, polyvinyl pyrrolidine, maleic acid/acrylic acid copolymers and partially hydrolyzed polyacrylamide. Suitable materials include Aqualon (Trade Mark) fibre and Aquasorb (Trade Mark) sheet (both ex Svenska).Such materials generally take up between 3 and 100 times their own weight, especially 30 to 60 times their own weight of urine. Sorbtion typically takes 5 to 7 seconds. The preferred sorbent is a thermally bonded air laid cellulose bearing an acrylate based superabsorbent. As previously mentioned superabsorbents can take a significant time to take up saline solutions. The preferred sorbent is very suitable because the cellulose web traps the urine until it is fully taken up by the superabsorbent.

Although it is intended that the bags of the invention be discarded shortly after use, pouch 1 can also include a biocide or biostate to prevent growth of bacteria, yeast or fungus in urine contained in the bag. As will become apparent in view of the method of use of the article of the invention the biocide should be without deleterious effect on sensitive skin. Those skilled in the art will be able to selected an appropriate preservative.

A tubular member 3 extends from bag 1. Preferably tubular member 3 extends from a point close to an edge or corner of the pouch. In general tubular member 3 will extend from a top surface of the pouch 1 to ensure that urine is rapidly transferred to the absorbent material 2. In some embodiments of the invention a reservoir (not shown) is provided to retain urine for a short period to prevent flooding of the sorbent material 2.

Tubular member 3 should be long enough such that when pouch 1 is situated between the thighs of a user the free end 4 extends to about the navel. Tubular member 3 will generally be about 50 to 150mm long and about 100 to 175mm in circumference at the free end 4 and for a distance of about 50mm for the free end 4.

Tubular member 3 is generally made of the same material as pouch 1. In some embodiments of the invention at least part of tubular member 3 is coloured thereby alleviating embarrassment of the user. Preferably substantially the whole apparatus is opaque or dimly translucent.

A portion of tubular member 3 at or near the free end 4 can be provided with a stiffener 5. Stiffener 5 can be a ring of metallic wire or a plastics material especially nylon. Stiffener 5 forces the free end of tubular member 3 out of a collapsed configuration thereby facilitating use of the article of the invention.

Free end 4 is preferably provided with valve 6. The function of valve 6 is to prevent escape of any free liquid from the bag while allowing easy use and preferably escape of displaced air from the bag. A suitable valve is a bunsen or duck-bill valve 10. Duck-bill valve 10 comprises a pair of resilient leaves 11 biased together and extending from the point of attachment to tubular member 3 preferably at stiffener 5, away from the free end 4. Duck bill valve 10 acts as a one-way valve. When closed objects travelling in direction A are prevented from passing the leaves 11 which are biased together, objects travelling in direction B can overcome the biasing and are not hindered. When, as for example the valve is in use in a bag of the invention, and leaves 11 are held apart air is permitted to escape pouch 1 in direction A.

Alternatively valve 6 may comprise a pair of flaps 12, 12a each partially covering the free end 4 of tubular member 3 and overlapping one another. The device operates in an analogous fashion to duck-bill valve 10. Those skilled will readily be able to device other suitable valves.

The valve and ring may be integrally moulded and inserted into free end 4 at any assembly stage.

A generally triangular or trapezoidal shape with the tubular member positioned towards a narrow portion of the bag thereby allowing a good fit between the legs of the user is preferred. A non-rigid pouch is preferred so that the bag conforms to the body and in the unused state occupies a small volume.

It is preferred that each surface of the article is nonlinear. The article is preferably prepared by dip-moulding and it has unexpectedly been found that when substantial flat areas are formed bubbles can form in the moulded article resulting in the increased possibility of punctures which are obviously not desired.

The bag is preferably provided with one or more pleats 20 especially substantially parallel to the bag's major axis.

These pleats serve two very important functions. First they reduce the possibility of bubble formation and secondly they allow the article to be packed in a compact form which is highly desirable as the article of the invention may be carried about the person or in a vehicle glove compartment.

In use the device is positioned between the thighs. The preferred shape of pouch 1 conforms to the slightly opened legs of the user. The user passes free end 4 of tubular member 3 over the penis (not shown) and micturates into the bag of the invention. The bag of the invention is preferably provided with closure means 30 such that the used bag may be sealed after use. Suitable closure means can comprise a cap or stopper. The free end of the tubular member can be folded over and secured with a clip or other fastener. Alternatively the tubular member may be sealed by wire or even by knotting or by use of a draw string.

Claims (7)

1. An external catheter comprising a bag of flexible water impermeable material the bag being provided with an entrance having a stiffening ring and containing a sorbent material and fitted with a valve for preventing escape of non-gaseous matter contained in the bag, wherein the bag is opaque, and is provided with one or more pleats.

2. An external catheter as claimed in claim 1 wherein the bag contains a biostat.

3. An external catheter as claimed in claim 1 or claim 2 further comprising sealing means for sealing the used bag.

4. An external catheter as claimed in any one of the preceding claims wherein the bag is triangular or trapezoidal.

5. An external catheter as claimed in any one of the preceding claims comprising natural rubber latex or paper.

6. An external catheter as claimed in any one of the preceding claims wherein the valve is a duck bill valve or comprises a pair of flaps each partially covering the entrace of the catheter and each partially overlapping the other.

7. An external catheter substantially as described herein by reference to any one of the figures.