GB1559825A

GB1559825A - Equipment for use in administering liquids into and removing liquids from human beings or animals

Info

Publication number: GB1559825A
Application number: GB3037075A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1976-07-13
Filing date: 1976-07-13
Publication date: 1980-01-30

Description

(54) IMPROVEMENTS IN AND RELATING TO EQUIPMENT FOR USE IN ADMINISTERING LIQUIDS INTO AND REMOVING LIQUIDS FROM HUMAN BEINGS OR ANIMALS (71) 1: ELLIS WHITESIDE CLARKE, a British Subject of 47 Deramore Drive, Belfast, BT9 SJS, Northern Ireland, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention is concerned with improvements in and relating to equipment for use in administering liquids into and removing liquids from human beings or animals.

In the administration or removal of liquids it is the usual practice to insert into a vein or into some other structure in the body of the patient a narrow tube such as an intravenous needle, a cannula or a catheter. For convenience narrow tubes of that kind will be referred to herein by the generic term insertion tubes. It is also the normal practice for an insertion tube to be provided at its proximal end with a female connector or socket which enables the insertion tube to be readily connected to any other piece of apparatus provided with a complementary male connector. The male and female connectors are tapered and are designed so that they can be retained in mutual engagement by friction alone. In some designs, however, releasable locking means is additionally provided.

Several standard forms of connectors are in use, one widely used being the Luer connector, and another being the Record connector.

It is usual for the male connector to be provided with proximal extension, in the the form of a rigid tubular part, to enable the connector to be readily manipulated and to be engaged tightly with the female connector. It is often desirable to insert the male connector into the socket quickly, and it is therefore the usual practice to provide a relatively large extension that can be handled without difficulty. Further, the provision of a relatively large extension reduces any likelihood of the male connector being contaminated by contact with the user's fingers.

It has also been the normal practice to provide a flexible connecting tube attached directly or indirectly to the proximal or rear end of the tubular extension. Sometimes a tubular component made from rubber is interposed between the extension and the connecting tube. Drugs can be injected through a hypodermic needle inserted into the tubular component, the hole formed by the needle sealing itself when the needle is withdrawn.

In use the connecting tube is usually bent into a wide loop and securely fastened to the patient in order to prevent an accidental pull on the connecting tube from dislodging the insertion tube. The combination of standard male connector, proximal extension, tubular rubber component and loop of the connecting tube normally extends for a distance of at least ten centimetres (as measured along that combination of components) from the insertion tube, and its movement is readily transmitted to the insertion tube. Precautions against such movement are customarily taken; for example the doctor may try to avoid inserting the insertion tube in the region of a joint and, when the insertion tube is inserted into a vessel in the patient's hand or arm, may loosely bandage the patient's arm to a padded splint. In spite of all this care, however, the insertion tube does tend to move in the surrounding tissue due to the remarkable elasticity of the skin and the comparative rigidity of the insertion tube and the other comments connected to it. Repeated longitudinal movements of the insertion tube are particularly undesirable since they can cause potentially harmful micro-organisms to be carried in from the surface of the skin to the deeper tissues and into the vein or other part of the body. It is probable that after the insertion tube has been inserted into the vein the moving tip of the insertion tube abrades the delicate lining of the vein, so increasing the chances of clot formation, and also irritates the muscle cells in the vein wall which respond by contracting and constrict the vein. Vein spasm is now becoming recognised as one of the main causes of failure of intravenous infusions. Inward movement. of flie insertion tube can also immediately stop the flow and this is presumably due to its tip becoming impacted against the vein wall. It seems likely that these various problems would be considerably lessened if the insertion tube were able to move with the tissues in its immediate vicinity while remaining unaffected by movements in other areas.

An object of the present invention is to provide means whereby these problems can be overcome or reduced.

According to the present invention there is provided in or for equipment for use in administering liquids into or removing liquids from human beings or animals, apparatus comprising a flexible connecting tube, a male connector of tapered shape connected to the connecting tube and formed with a through passage communicating with the interior of the connecting tube, and an extension to the male connector, extending proximally of the male connector and external to the connecting tube, by means of which extension the male connector can be manipulated into frictional engagement with a female connector or socket of complementary tapered shape at the proximal end of an insertion tube the female connector or socket being formed with a through passage communicating with the interior of the insertion tube, the arrangement being such that when said connectors are interengaged there is communication between the interior of the connecting tube and the interior of the insertion tube, a portion of the tube being bent or bendable into a tight arc of substantially semi-circular shape stemming from a point at or closely adjacent to the proximal end of the male connector, the extension being either shaped to accommodate such an arc or being frangible to enable that portion to be bent into such an arc after the male connector has been engaged with the female connector and at least part of the extension has been broken away.

In use, when a vein or other vessel has been cannulated with the insertion tube, the male connector can be manipulated into engagement with the female connecttor by means of the extension. The said portion of the tube can then be bent into said arc, if it has not already been so bent, whereupon the engaged connectors and said portion of the tube can be secured to neighbouring areas of the patient's skin by means of adhesive tape. As the points of attachment of the connectors and the tube to the skin are relatively close, there is in use little tendency for there to be relative movement between the insertion tube and the vessel.

Embodiments of the present invention will be described in greater detail, by way of example, with reference to the accompanying drawings, in which: - Figure 1 is a side view of a cannula to which is connected apparatus embodying the present invention.

Figure 2 is a section through a male connector and extension of the apparatus shown in Figure 1, to a larger scale than Figure 1, along the line 2-2 of Figure 3, Figure 3 is an elevation of the connector and extension as viewed from the right of Figure 2, Figure 4 is a plan view of the connector and extension shown in Figures 2 and 3, Figure 5 is similar to Figure 2 but includes part of the cannula in section and part of a connecting tube.

Figure 6 is similar to Figure 3 but includes part of the connecting tube and indicates part of the cannula in chain-dotted lines, Figure 7 is a section along the line 7-7 of Figure 5, Figure 8 is a side view similar to Figure 1 but illustrating a different construction of connector and extension, only a very small portion of the extension remaining after the remainder has been broken away by the user, Figure 9 is a front view, to a larger scale, of the connector and extension of the apparatus shown in Figure 8, but before any of the extension has been broken away, Figure 10 is a plan view of the connector and extension shown in Figure 9, and Figure 11 is a section, also to an enlarged scale, of part of what is shown in Figure 8.

Referring firstly to Figures 1 to 7 the apparatus is shown connected to a cannula 10 of a conventional type including a narrow tube 11 with a female connector or socket 12 at its proximal end. The dimensions of the socket 12 are those of a standard Luer connector. The standard Luer connector has a length of about 7 mm, a diameter of 4 mm at the narrower end and 5 mm at the broader end. The apparatus includes a body 13 formed as a unitary moulding of a suitable plastics material, the body being so shaped as to be capable of being moulded in a simple two-part mould. Part of the body 13 constitutes a male connector 14 of which the dimensions are those of a standard Luer connector.

The remainder of the body 13 constitutes an extension 15, extending proximally of the connector. The extension 15 may be thought of as a proximally extending length of tube of which that part immediately adjacent to the male connector has been bent into a tight semi-circular arc, and of which the outermost part has been removed and opened out as illustrated. Thus the extension in effect has two spaced wings 16 of which the outer edges are separated by a gap. That part of the gap leading into the straight non-arcuate, part of the extension is rendered narrower than the remainder of the gap by the provision on the wings of a pair of ribs 17 directed each towards the other. As can be seen in figure 4 the wings are not quite parallel with each other but are inclined so that their straight parts are rather closer together than are their arcuate parts.

The apparatus also includes a connecting tube 18 comprising a length of flexible pvc tube of a kind widely used in medical apparatus but narrower than that hitherto in general use in administration sets. During the manufacture of the apparatus the end part of the tube is dipped in a solvent such as cyclohexanone and the end portion is inserted into the male connector with the adjacent portion of the tube at least substantially co-axial with the end portion.

That adjacent portion is then progressively inserted into the extension through the gap between the wings, so that it forms a tight arc of semi-circular shape.

If the tube were unsupported there might be a tendency for it to kink when bent into such a tight arc. To avoid that possibility the wings 16 of the extension are slightly closer together than the diameter of the tube so that as shown in Figure 7 the tube is resiliently distorted to a slight extent and assumes an oval shape in cross-section, the disposition of the oval section being at right angles to that of the oval section which would occur as the tube was starting to kink. As the tube passes between the ribs 17 it is resiliently deformed to a slightly greater extent. As the solvent evaporates the tube becomes permanently attached to the body 13. The ribs 17 assist in retaining the tube in place, particularly while the solvent evaporates.

In a typical form of apparatus the tube 18 is 90 cm long, 1.5 mm in internal diameter and 2.5 mm in external diameter.

The apparatus shown in Figures 8 to 11 comprises a body 20 and a length of tube 21 that is similar to the tube 18. The body is made as a unitary moulding of a suitable plastics material such as a derivative of polystyrene. The body 20 comprises a male connector 22, similar to the connector 14, with a proximal extension 23. That part of the extension 23 immediately adjacent to the connector 22 comprises an outwardly directed annular flange 24. The main part of the extension comprises a pair of partcylindrical arms 25 extending proximally from the flange 24.

During assembly the end portion of the tube 21 is dipped in a solvent, as before, and inserted lengthwise of the extension into the male connector 22, to which it becomes permanently attached when the solvent evaporates.

In use the user holds the arms 25 and manipulates the connector 22 into place.

When the connector 22 is in frictional engagement with the complementary socket the user bends the arms 25 outwards and the arrangement is such that they break off from the flange 24 and can be discarded.

The tube 21 can then be bent into a tight arc of semi-circular or substantially semicircular shape stemming from a point closely adjacent to the proximal end of the connector 22, as shown in Figures 8 and 11.

If for any reason it becomes necessary to disconnect the connector 22 from the socket, the user can insert a suitable tool, or even his finger-nail between the socket and the laterally extending flange 24 and pull the connector out of engagement with the socket.

In each of the embodiments illustrated the socket is provided with an outwardly directed locking flange 26 at its proximal end. This flange of standard shape and is intended for use with a standard type of locking device sometimes provided in conjunction with male connectors, but not incorporated in either of the forms of apparatus illustrated in the accompanying drawings.

The proximal end of the tube, 18 or 21 as the case may be, would normally be connected to a standard female connector, but when the apparatus is to be used in the administration of liquids the tube may lead to a tubular rubber component of the kind referred to above as being sometimes incorporated in previously known equipment, the rubber component being in turn connected to another tube which terminates in a standard female connector. In a further modification the tube 18 or 21 is made to form a permanent extension of the administration set, the tube being joined directly to the tubular rubber component.

With this last arrangement no disconnection can be made to flush out any air trapped in the infusion tube, and it is necessary to insert a hypodermic needle into the rubber tube to release trapped air.

When the apparatus is to be used in the administration of liquids, the apparatus, if not already forming part of an administration set, is connected by means of a female connector to an administration set.

Apparatus embodying the invention may be used in the following manner. If the patient is wearing an upper garment, the male connector, with a cover of the kind normally provided, and the connecting tube are passed in through the neck aperture of the garment then down and through the drawn-up sleeve. The cover is removed from the male connector and the infusion liquid flushed through the tubing. As soon as the vein is cannulated the doctor takes the modified male connector by the extension and firmly inserts the connector into the standard female socket on the cannula and the infusion is started immediately. If the extension is of the kind shown in Figures 9 and 10, then before releasing his grip on the cannula the doctor bends the arms 25 outwards and breaks them away.

The cannula is attached to the skin with a small piece of adhesive tape and a tight semi-circular arc or U-bend is made in the tube (if not already formed) to bring it approximately parallel with and close to the socket where it is taped down to the same piece of tape. More pieces of tape are used to hold the tube in place on its course up the arm and care is taken to make secure a final attachment in the region of the collar bone. When a tubular rubber component is included, it is good practice also to attach that part of the administration set just proximal to the rubber component to the patient's clothing in the front shoulder region with a strong safety pin.

The cannula is covered with a small dressing or transparent plastics patch and the sleeve drawn down over it. A splint is hardly ever required and the patient is able to use his arm.

This means of administering liquid intravenously, to a vein in the patient's arm or hand has been found to provide benefits in addition to those already mentioned. For example, garments may be worn in the normal manner so helping to prevent the arm and shoulder from being chilled and thus causing the veins to constrict. As the infusion liquid flows through the thin flexible tube in contact with the arm it becomes prewarmed and on reaching the vein is less likely to cool and so constrict the vein.

Experience so far suggests that with restless or uncooperative patients the cannula is less inclined to become displaced and in contrast to the present methods there seems to be little risk of the tube becoming disconnected from the cannula.

WHAT I CLAIM IS: - 1. In or for equipment for use in administering liquids into or removing liquids from human beings or animals, apparatus comprising a flexible connecting tube, a male connector of tapered shape connected to the connecting tube and formed with a through passage communicating with the interior of the connecting tube, and an extension to the male connector, extending proximally of the male connector and external to the connecting tube, by means of which extension the male connector can be manipulated into frictional engagement with a female connector or socket of complementary tapered shape at the proximal end of an insertion tube, the female connector or socket being formed with a through passage communicating with the interior of the insertion tube, the arrangement being such that when said connectors are interengaged there is communication between the interior of the connecting tube and the interior of the insertion tube, a portion of the tube being bent or bendable into a tight arc of substantially semi-circular shape stemming from a point at or closely adjacent to the proximal end of the male connector, the extension being either shaped to accommodate such an arc or being frangible to enable that portion to be bent into such an arc after the male connector has been engaged with the female connector and at least part of the extension has been broken away.

2. Apparatus according to Claim 1 in which the extension is shaped to accommodate said portion of the tube bent into an arc, that portion being permanently secured to the extension.

3. Apparatus according to either of Claims 1 and 2 in which the extension comprises spaced wings between which lies said portion of the connecting tube, there being a gap between the wings such that during assembly the distal end portion of the connecting tube can be inserted into the connector with the adjacent portion of the tube at least substantially co-axial with the end portion, and said adjacent portion can then be bent into arcuate shape and pass through the gap so as to lie between the wings.

4. Apparatus according to Claim 3 in which at least part of the gap is narrower at its mouth than in its interior so that the tube has to be resiliently deformed in passing into the gap.

5. Apparatus according to either of Claim 3 and 4 in which the male connector and extension are formed as a unitary moulding of a plastics material in a twopart mould.

6. Apparatus according to Claim 1 in which the extension is frangible and the arrangement is such that a small portion of the extension remains after most of the extension has been broken away, that small portion extending a relatively short distance

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. administration of liquids, the apparatus, if not already forming part of an administration set, is connected by means of a female connector to an administration set. Apparatus embodying the invention may be used in the following manner. If the patient is wearing an upper garment, the male connector, with a cover of the kind normally provided, and the connecting tube are passed in through the neck aperture of the garment then down and through the drawn-up sleeve. The cover is removed from the male connector and the infusion liquid flushed through the tubing. As soon as the vein is cannulated the doctor takes the modified male connector by the extension and firmly inserts the connector into the standard female socket on the cannula and the infusion is started immediately. If the extension is of the kind shown in Figures 9 and 10, then before releasing his grip on the cannula the doctor bends the arms 25 outwards and breaks them away. The cannula is attached to the skin with a small piece of adhesive tape and a tight semi-circular arc or U-bend is made in the tube (if not already formed) to bring it approximately parallel with and close to the socket where it is taped down to the same piece of tape. More pieces of tape are used to hold the tube in place on its course up the arm and care is taken to make secure a final attachment in the region of the collar bone. When a tubular rubber component is included, it is good practice also to attach that part of the administration set just proximal to the rubber component to the patient's clothing in the front shoulder region with a strong safety pin. The cannula is covered with a small dressing or transparent plastics patch and the sleeve drawn down over it. A splint is hardly ever required and the patient is able to use his arm. This means of administering liquid intravenously, to a vein in the patient's arm or hand has been found to provide benefits in addition to those already mentioned. For example, garments may be worn in the normal manner so helping to prevent the arm and shoulder from being chilled and thus causing the veins to constrict. As the infusion liquid flows through the thin flexible tube in contact with the arm it becomes prewarmed and on reaching the vein is less likely to cool and so constrict the vein. Experience so far suggests that with restless or uncooperative patients the cannula is less inclined to become displaced and in contrast to the present methods there seems to be little risk of the tube becoming disconnected from the cannula. WHAT I CLAIM IS: -

1. In or for equipment for use in administering liquids into or removing liquids from human beings or animals, apparatus comprising a flexible connecting tube, a male connector of tapered shape connected to the connecting tube and formed with a through passage communicating with the interior of the connecting tube, and an extension to the male connector, extending proximally of the male connector and external to the connecting tube, by means of which extension the male connector can be manipulated into frictional engagement with a female connector or socket of complementary tapered shape at the proximal end of an insertion tube, the female connector or socket being formed with a through passage communicating with the interior of the insertion tube, the arrangement being such that when said connectors are interengaged there is communication between the interior of the connecting tube and the interior of the insertion tube, a portion of the tube being bent or bendable into a tight arc of substantially semi-circular shape stemming from a point at or closely adjacent to the proximal end of the male connector, the extension being either shaped to accommodate such an arc or being frangible to enable that portion to be bent into such an arc after the male connector has been engaged with the female connector and at least part of the extension has been broken away.

rearwardly of the male connector and affording lateral projections whereby the male connector can be pulled out of engagement with the female connector.

7. Apparatus according to any of the preceding Claims in which the proximal end of the connecting tube is directly or indirectly connected to a female connector or socket by means of which the apparatus can be coupled to other apparatus.

8. Apparatus according to any of Claim 1 to 6 constituting a permanent part of an administration set.

9. In or for equipment for use in administering liquids into or removing liquids from human beings or animals, apparatus comprising a flexible connecting tube connected to a male connector or tapered shape, and with an extension, substantially as hereinbefore described with reference to and as shown in Figures 1 to 7 of the accompanying drawings.

10. In or for equipment for use in administering liquids into or removing liquids from human beings or animals, apparatus according to Claim 1 and substantially as hereinbefore described with reference to Figures 8 to 11 of the accompanying drawings.