WO2006010929A2

WO2006010929A2 - Lock mechanism for a catheter

Info

Publication number: WO2006010929A2
Application number: PCT/GB2005/002952
Authority: WO
Inventors: Robert Graham Urie
Original assignee: Mediplus Limited
Priority date: 2004-07-30
Filing date: 2005-07-28
Publication date: 2006-02-02
Also published as: GB2416818A; GB0416981D0; WO2006010929A3

Abstract

A proximal end adaptor for a catheter has a first elongate member having a first portion defining a first axial lumen therethrough adapted to receive an inner sleeve of the catheter and a second elongate member having a second axial lumen adapted to receive, in sliding engagement, at least part of the first portion of the first elongate member. The second elongate member has a catheter engagement means adapted to engage an outer sleeve of the catheter, wherein the sliding engagement of the first and second elongate members enables relative longitudinal displacement between the inner and outer sleeves of the catheter. The proximal end adaptor has connecting means attached to the first elongate member for connecting the adaptor to a collection receptacle, and a locking mechanism to enable the first and second elongate members to be locked in at least a first predetermined position by a relative rotation of the first and second elongate members about their axis, to thereby prevent said relative longitudinal displacement of the catheter sleeves.

Description

LOCKMECHANISMFORACATHETER

The present invention relates to catheters and locking mechanisms for catheter apparatus.

Conventional urinary drainage catheters generally comprise a tube having a distal end which is inserted into a patient's body, a proximal end which remains outside the patient's body, and at least one lumen extending through the tube for the passage of urine out of the body. The distal end is introduced into the bladder via the urethra, and extends a short distance into the bladder where it is maintained in position by a suitable retention mechanism.

There are a number of conventional retention mechanisms available in the art, one of which provides an inflatable balloon at the distal end of the catheter, which is inflated after being introduced into the bladder via the urethra. The inflated balloon engages with the neck of the bladder, thereby preventing the catheter from inadvertently being withdrawn from the bladder.

Other retention mechanisms make use of a flexible, resilient wing structure at the distal end of the catheter, in which the wings can be compressed (closed) umbrella-like to be aligned with the catheter for introduction through the urethra. Once the wing structure reaches the bladder, it is allowed to spring back into an appropriate expanded or 'open' form to prevent egress of the catheter from the bladder.

Another retention mechanism is described in the pending International patent application PCT/GB2003/005022, in the name of Mediplus Limited. In this type of catheter the retention mechanism is based on a deformable zone of an outer sleeve of the catheter, the outer sleeve surrounding an inner sleeve which are both fixed together at the distal ends of the sleeves. The inner sleeve is lubricated so as to allow relative longitudinal displacement between the outer and inner sleeves of the catheter. The deformable zone comprises a plurality of elongate slits which are opened by deformation of the zone via a compression mechanism, which is applied after introduction of the distal end of the catheter into the bladder.

The deformation of the zone causes the zone walls to bulge or splay outwardly, whereby the splayed walls engage with the neck of the bladder, preventing egress of the distal end of the catheter past the bladder neck.

The open elongate slits are generally longitudinally aligned with an aperture in the inner sleeve of the catheter, which allows urine in the bladder to drain away by means of a lumen inside the inner sleeve, into a collection receptacle, such as a urine drainage bag.

The catheter of the above application also provides a mechanism for locking the inner and outer sleeves in a particular longitudinal displacement, corresponding to the open slit configuration. Locking mechanisms are necessary when the walls of the outer sleeve are resilient such that there is a tendency for them to try to close the slits that have been opened up in the open configuration. The necessity for any such locking mechanism may also depend upon the frictional resistance to the relative longitudinal movement of the inner and outer sleeves.

A known locking mechanism for locking the inner and outer sleeves comprises a circlip, or spring clip, clipped onto the proximal end of the inner sleeve which emerges from the proximal end of the outer sleeve. The clip extends around the inner sleeve in a tight frictional engagement that resists any longitudinal movement of the clip along the inner sleeve. The clip bears against the end wall of the outer sleeve at the proximal end, by way of an intervening olive, which has a tapered leading edge to engage with, and slightly under, the proximal end of the outer sleeve.

By appropriate positioning of the clip along the proximal end portion of the inner sleeve, the degree of longitudinal compression of the outer sleeve may be controlled, such that the outer sleeve can be locked in a position corresponding to the open configuration.

However, a potential disadvantage of a clip based locking mechanism is that the outer sleeve must be held in a compressed position (typically corresponding to the open configuration) while attempting to engage the clip with the inner sleeve.

Moreover, lateral adjustments in the position of the clip may also be difficult to accomplish where tight frictional engagement of the clip with the inner sleeve could prevent easy movement of the clip along the inner sleeve.

To ensure that the clinician achieves the correct degree of compression of the deformable zone they may conventionally rely . on visual indicators located on the inner sleeve, in order to assess the extent of the relative longitudinal displacement between the inner and outer sleeves.

One objective is to provide a proximal end adaptor having a locking mechanism for a catheter which is easy to use and can readily be operated by a single clinician. Another object is to provide a proximal end adaptor having a locking mechanism for a catheter which has a predetermined lockable position allowing the clinician to easily identify that the catheter is in the correct open configuration.

Another objective is to provide a proximal end adaptor having a locking mechanism for a catheter which ensures minimal or no leakage from the small gap between the inner and outer sleeves of the catheter.

An object of the present invention is to provide an improved proximal end for a catheter achieving one or more of the above objectives.

Hereinafter, it is to be understood that all references to 'catheter' are to be taken as referring to a catheter having two components that are to be longitudinally displaceable relative to one another, e.g. the inner and outer sleeves of a catheter as described above, in which compression of the outer sleeve leads to deformation of a deformable zone in the distal end of the outer sleeve, thereby opening elongate slits in fluid communication with an aperture in the distal end of the inner sleeve.

According to a first aspect of the present invention there is provided a proximal end adaptor for a catheter, comprising: a first elongate member having a first portion defining a first axial lumen therethrough adapted to receive an inner sleeve of the catheter; a second elongate member having a second axial lumen adapted to receive, in sliding engagement, at least part of the first portion of the first elongate member, the second elongate member further having a catheter engagement means adapted to engage an outer sleeve of the catheter, wherein the sliding engagement of the first and second elongate members enables relative longitudinal displacement between the inner and outer sleeves of the catheter; connecting means attached to the first elongate member for connecting the adaptor to a collection receptacle, and a locking mechanism to enable the first and second elongate members to be locked in at least a first predetermined position by a relative rotation of the first and second elongate members about their axis, to thereby prevent said relative longitudinal displacement of the catheter sleeves.

Embodiments of the present invention will now be described by way of example and with reference to the accompanying drawings in which:

Figure 1 shows an exploded perspective, side and top view of a proximal end adaptor according to the present invention; Figure 2 shows a cross-sectional side view of the proximal end adaptor of figure 1 in assembled and closed configuration;

Figure 3 shows a cross-sectional side view of the proximal end adaptor of figure 1 in assembled and open configuration;

Figures 4a and 4b show side views of the proximal end adaptor of figure 1, with an attached catheter, in closed and open configurations respectively.

Figures 5a and 5b show side views of the proximal end adaptor of figure 1, illustrating the locking mechanism in open and closed configurations respectively. Figure 6 schematically illustrates example configurations of the locking mechanism track.

Figures 7a and 7b show side views of a further proximal end adaptor according to the present invention, illustrating the leakage bellows in open and closed configurations respectively. With reference to figure 1, there is shown a preferred embodiment of a proximal end adaptor 10 according to the present invention. The adaptor 10 is shown in disassembled form and comprises a first elongate member 12. a second elongate member 16 and a connecting means 19. Also shown is the proximal end of a catheter 50 having outer 51 and inner 52 sleeves.

The first elongate member 12 comprises a first portion 13 which is preferably elongate in form and defines a first axial lumen 13a therethrough, which is more clearly illustrated in figure 2, in which the adaptor 10 is shown assembled in a side cross-sectional view with a catheter 50 inserted. The first axial lumen 13a is open at both ends and defines an inner surface of the first portion 13 of the first elongate member 12. The bore size of the first axial lumen is uniform along the length of the first portion 13. The first axial lumen 13a is adapted to receive the inner sleeve 51 of the catheter 50 and to engage the outer surface of the inner sleeve 51 in a tight frictional engagement.

Referring to figure 2, the second elongate member 16 comprises a lumen extending therethrough, comprising first and second lumen portions. The first lumen portion is defined by a second axial lumen 16a, and the second lumen portion is defined by a third axial lumen 19a. The second axial lumen 16a is adapted to receive, in sliding engagement, at least part of the first portion 13 of the first elongate member 12. The bore size of the second axial lumen 16a is uniform along the length of the first lumen portion and is sufficiently close to the outer diameter of the first portion 13 of the first elongate member 12, so as to minimise any gap between the outer surface of the first portion 13 and the inner surface of the second elongate member 16 defined by the second axial lumen 16a, to prevent any leakage of urine. The outer surface of the first portion 13 and the inner surface of the second axial lumen 16a may also be sufficiently close so as to allow a degree of frictional coupling between the respective surfaces to provide at least partial resistance to the first 12 and second 16 elongate members being drawn apart.

In preferred embodiments, the length of the second axial lumen 16a is substantially equivalent to the length of the first portion 13 of the first elongate member 12, so as to allow the first portion to be substantially fully inserted into the second axial lumen, as is shown in figure 2.

Referring again to figure 2, there is also shown a catheter engagement means 19, which is preferably integral to the second elongate member 16. In preferred embodiments, the catheter engagement means 19 is the third axial lumen 19a and defines an inner surface of the second elongate member 16 for frictional coupling to the outer catheter sleeve 50. Preferably, the bore size of the third axial lumen 19a is substantially equivalent to the outer diameter of the outer catheter sleeve 51, so as to engage the outer sleeve in a tight frictional engagement.

The catheter 50 is inserted into the third axial lumen 19a so that the length of the portion of the outer catheter sleeve 51 engaged is preferably substantially equivalent to the length of the third axial lumen 19a.

To prevent any leakage from between the inner surface of the third axial lumen 19a and the outer catheter sleeve 51, a water-proof adhesive may preferably be used to bond the surfaces together, thereby forming a leakage proof seal. The third axial lumen 19a is in communication with the second axial lumen and both are preferably substantially co-axial, as shown in figure 2. However, the second 16a and third 19a axial lumens are preferably separated by a first annular lip 20 located inside the second elongate member 16. The first annular lip 20 defines a centra] aperture 20a having a bore size, in the region of the lip, which is smaller than the bore sizes of the second 16a and third 19a axial lumens and is preferably substantially equivalent to the outer diameter of the inner sleeve of the catheter 52.

As shown in figure 2, the first annular lip 20 allows the inner catheter sleeve 52 only to pass through the central aperture 20a into the second axial lumen 16a, and into the first axial lumen 13 a of the first portion 13 of the first elongate member 12, which is engaged with the second axial lumen 16a. The inner sleeve 51 is thereby engaged by the inner surface of the first axial lumen 13 a in a tight frictional engagement.

The first annular lip 20 acts, in part, acts as an aperture stop or rest for the abutting end wall of the outer catheter sleeve 51, which prevents the outer sleeve 51 from entering the second axial lumen 16a during insertion of the catheter 50 into the third axial lumen 19a.

The first elongate member 12 further comprises a second portion 14. which is preferably elongate in form, and is preferably relatively shorter than the first portion 13. The second portion 14 defines a fourth axial lumen 14a therethrough, which is open at both ends, as illustrated in figure 2. Preferably the bore size of the fourth axial lumen 14a is uniform along the length of the second portion 14 of the first elongate member 12, although alternatively, the bore size may vary along the length of the lumen 14a. In preferred embodiments, the first 13a and fourth 14a axial lumens are substantially co-axial and are in fluid communication with each other. However, the first 13a and fourth 14a axial lumens are preferably separated by a second annular lip 21 located inside the first elongate member 12. The second annular lip 21 defines a central aperture 21a having a bore size, in the region of the lip, which is smaller than the bore sizes of the first 13a and fourth 14a axial lumens and is preferably substantially equivalent to the inner diameter of the inner sleeve of the catheter 52.

The second annular lip 21 acts as an aperture stop or rest for the abutting end wall of the inner catheter sleeve 52, which prevents the inner sleeve 52 from entering the fourth axial lumen 14a during insertion of the catheter 50 into the adaptor 10.

Referring to figures 1 and 2 again, in preferred embodiments, the connecting means 19 is attached to the second portion 14 of the first elongate member 12. Preferably, the second portion 14 includes a thread for threading engagement with the connecting means 19, such as a screw thread etc. However, it is to be appreciated that any suitable form of attachment means, including adhesives, may be used to connect the connecting means 19 to the second portion 14 of the first elongate member 12. provided the attachment means are substantially leak-proof.

The connecting means 19 is preferably in the form of a connecting collar having a lumen therethrough, as shown in figures 1 and 2, which encloses a portion of the outer surface of the second portion 14 of the first elongate member 12. The connecting means 19 is preferably substantially co-axial with the fourth axial lumen 14a and is in fluid communication with the fourth axial lumen 14a. The connecting means 19 is preferably adapted for connection to standard medical connectors and/or receptacles and may include screw threads or other forms of leak-proof attachment means. Most preferably the connecting means 19 is a Luer cap.

In preferred embodiments, the adaptor 10 further comprises at least one seal 23a, 23b to minimise leakage of fluid between the outer surface of the first portion 13 of the first elongate member 12 and the inner surface of the second axial lumen 16a. Preferably the seal 23a, 23b is located on the outer surface of the first portion 13 of the first elongate member 12, but alternatively may be located on the inner surface of the second axial lumen 16a, or alternatively still at least one seal can be located on both surfaces.

In the preferred embodiment as exemplified by figures 1 and 2, the adaptor is configured so as to comprise two O-ring seals 23 a. 23b located in circumferential recesses 22a, 22b respectively in the outer surface of the first portion 13 of the first elongate member 12, the recesses 22a, 22b being preferably located close to one end of the first portion 13. Alternatively, the O-ring seals 23a, 23b can be attached directly to the outer surface of the first portion without the need for circumferential recesses 22a, 22b, however, it is known that such an arrangement tends to increase the gap between the outer surface of the first portion 13 of the first elongate member 12 and the inner surface of the second axial lumen 16a and so is not preferred.

The O-ring seals 23 a, 23b may be preferably secured within the circumferential recesses by means of frictional coupling alone or else may be bonded by a suitable water-proof adhesive. It is to be appreciated that although the exemplar}' embodiment includes two O-ring seals 23a, 23b, this is not intended to be limiting and one or a plurality of seals located at varying positions along the first portion of the first elongate member could be used.

The O-ring seals 23a, 23b also provide additional frictional resistance between the surfaces when inserting, and drawing, the first and second elongate members apart.

Preferably, the O-ring seals can be made from any suitable plastic or rubber material, and are preferably resiliently flexible.

Referring to figure 3, there is shown the adaptor of figure 2, in which the first 12 and second 16 elongate members have been longitudinally displaced along the axis of the first axial lumen 13a relative to each other. Accordingly, when the second elongate member 16 is longitudinally displaced with respect to the first elongate member 12, the first annular lip 20 exerts a longitudinal compression force on the end wall of the outer catheter sleeve 51, such that the annular lip 20 pushes the outer sleeve 51 along the inner sleeve 52 (which is essentially fixed due to frictional engagement) by an amount equivalent to the displacement of the lip 20.

The resulting compression of the outer catheter sleeve 51 is sufficient to deform the deformable zone (not shown) of the outer sleeve 51, so as to splay the walls of the zone and open the elongate slits (not shown).

The first elongate member 12 and the second elongate member 16, are lockable in at least a first predetermined 'open' position (as shown in figure

3) by a locking mechanism which allows the first elongate member 12 and the second elongate member 16 to be longitudinally displaced by a consistent and predetermined amount so as to reliabfy and accurately deform the outer catheter sleeve 51 in repeated operations.

The relative displacement of the outer catheter sleeve 51 with respect to the inner catheter sleeve 52 is illustrated in figures 4a and 4b, wherein it is clear that a longitudinal displacement between the first 12 and second 16 elongate members, causes a corresponding displacement between the outer 51 and inner 52 catheter sleeves.

In the exemplary embodiment, as shown in figures 1 and 5a and 5b, the locking mechanism comprises at least one pin 24 and at least one track 25. The track 25 includes at least a first locking slot position 26. It is to be appreciated that any number of pins and tracks may be used in the locking mechanism of the present invention. Preferably, the at least one pin 24 is located on the outer surface of the first portion 13 of the first elongate member 12.

The at least one track 25 is preferably located in a portion 17 of the outer surface of the second elongate member 16, the portion 17 substantially overlying the at least one pin location when the first 12 and second 16 elongate members are engaged, such that the pin 24 engages with the track 25 and is constrained to move within the track 25. Correspondingly, this consequently constrains the amount of longitudinal displacement allowable between the first elongate member 12 and second elongate member 16.

The track 25 may preferably extend completely through the outer wall of the portion 17 of the outer surface of the second elongate member 16, so as to be an open track, as shown in figures 1 and 5a and 5b, or alternatively, may be a recess (not shown) extending only partially through the outer wall of portion 17. having a sufficient depth to prevent the pin 24 from dislodging itself from the recessed track.

In preferred embodiments, the track 25 is in the form of a letter T, with the linear part of the track 25 having a direction substantially parallel to the axis of the second axial lumen 16a. The linear part of the track 25 preferably has an extent substantially equal to the amount of longitudinal displacement needed between the inner 52 and outer 51 catheter sleeves, in order to open the slits in the deformable zone. The curved part of the 'J' track 25, serves as the first locking slot position 26, whereby when the second elongate member 16 is longitudinally displaced and partially rotated relative to the first elongate member 12, the pin 24 follows the curved part of the track 25, wherein it is held by friction in the first locking slot position 26.

Since the extent of the linear part of the track 25 is predetermined to correspond to the actual amount of longitudinal displacement needed to accurately deform the outer catheter sleeve 51, the clinician can advantageously operate the catheter 50 without the need to refer to visual indicators on the inner sleeve 52, thereby avoiding possibly under, or over, deforming the deformable zone.

Moreover, the longitudinal displacement and rotation of the second elongate member 16 can be performed in a single action, which enables the catheter 50 to be easily locked, thereby advantageously allowing the adaptor 10 to be operated by a single clinician.

The compressed outer catheter sleeve 51, is typically sufficiently resilient so as to exert a restoring force on the first annular lip 2O₅ such that the second elongate member 16 has a tendency to push towards the first elongate member 12. but is prevented from moving by the pin 24 in the locking mechanism. The force on the pin 24 thereby prevents it from inadvertently disengaging from the locking slot position 26.

It is to be appreciated that, although the preferred embodiments are described as having a 'J' shaped track 25, this is not intended to be limiting, and any suitable track configuration may be used provided it is capable of locking the first elongate member 12 and the second elongate member 16 in at least a first predetermined open position, to thereby prevent a relative longitudinal displacement between the inner 51 and outer 52 sleeves of the catheter 50.

By way of example, figures 6(a) to 6(g) illustrate other preferred track configurations according to the present invention. As will be appreciated in each example 6(a) to 6(g), the track 25 comprises a substantially linear part and one or more locking slot positions 26. The locking slot positions 26 include or define circumferential component portions of the track 25, i.e. they include a component in a substantially orthogonal direction to the direction of the linear part, which extends circumferentially around a portion of the second elongate member 16. It is to be noted that each track 25 requires the first elongate member 12 and second elongate member 16 to be relatively rotated with respect to the other, so that the pin engages with the locking slot position 26.

Preferably, once the first elongate member 12 and the second elongate member 16 are engaged, with the pin 24 constrained within the track 25, the first elongate member 12 and the second elongate member 16 are subsequently not intended to be disengaged. Thereafter the adaptor 10 of the present invention may be considered to be a single component in any urinary drainage system. Referring to figures 7a and 7b. there is shown a further exemplar)' embodiment according to the present invention. The adaptor 10 further comprises an outer leakage bellows 27 to contain an)' leakage of urine arising from the small gap between the outer surface of the first portion 13 of the first elongate member 12 and the inner surface of the second elongate member defined by the second axial lumen 16a. The leakage bellows 27 are extendible and collapsible substantially along the axis of the second axial lumen 16 a, as shown in figures 7a and 7b respectively. Preferably, the leakage bellows 27 are arranged so as to enclose at least the portion of the adaptor 10 in the region of the locking mechanism, and to thereby operably extend when the first elongate member 12 and the second elongate member 16 are longitudinally displaced so as to be locked into an open position.

The first end wall 27a of the leakage bellows 27 is bonded to the part 15 of the outer surface of the second portion 14 of the first elongate member 12, and the second end wall 27b is bonded to the part 18 of the outer surface of the second elongate member 16. The bonding is resistive to fluid leakage and is preferably achieved by way of a water-proof adhesive so as to form leakage-proof seals at the respective interfaces of the walls and the surfaces.

Preferably, the leakage bellows 27 may be any suitable elastic material, such as a relatively thin rubber tubing, or alternatively may comprise a concertina structure having a plurality of folds. The concertina structure could be made from a single plastic component, or may optionally be formed as a ribbed support frame (e.g. a cage of relatively thin wire) covered in a suitable water-proof elastic skin. In preferred embodiments, the leakage bellows 27 are at least partially transparent so as to allow the enclosed locking mechanism to be viewed by the clinician. In the embodiment shown, the leakage bellows 27 must be resilient to a torsional force, since the second elongate member 36 is partially rotated in order to lock, and unlock, the locking mechanism.

The first 12 and second 16 elongate members can be made from an}⁷ suitable material such as PVC, which has sufficient strength and rigidity so as to provide a reliable and sturdy locking mechanism. However, the material may have at least a partial flexibility to allow the first and second elongate members to be push-fit together during assembly of the adaptor 10. The connecting means 19 may also be formed from a similar material.

In the preferred embodiment, as shown in figure 1, a part 15 of the outer surface of the second portion 14 of the first elongate member 12 may be textured to improve grip for the clinician. Additionally, preferably part 18 of the outer surface of the second elongate member 16 may also be textured to provide a similar advantage. The texturisations may preferably be in the form of ribbed structures, as illustrated, or else may correspond to a flattened/recessed, winged or knurled grip type structure. It is to be appreciated that any suitable texture may be used, and the examples described and illustrated are not intended to be limiting.

The connecting means 19 may also have an outer surface which is textured to improve grip to assist in securing the means to a collection receptacle.

Any conventional technique may be used to fabricate the components, such as injection moulding, or alternatively the components can be formed from single blocks suitably machined so as to bore the axial lumens and define the surface features. Although the proximal end adaptor of the present invention is ideal for controllably operating a catheter, it will be recognised that one or more of the principles can extend to other types of medical and/or leak -proof connectors.

Other embodiments are intentionally within the scope of the appended claims.

Claims

1. A proximal end adaptor for a catheter, comprising: a first elongate member having a first portion defining a first axial lumen therethrough adapted to receive an inner sleeve of the catheter; a second elongate member having a second axial lumen adapted to receive, in sliding engagement, at least part of the first portion of the first elongate member, the second elongate member further having a catheter engagement means adapted to engage an outer sleeve of the catheter, wherein the sliding engagement of the first and second elongate members enables relative longitudinal displacement between the inner and outer sleeves of the catheter; connecting means attached to the first elongate member for connecting the adaptor to a collection receptacle, and a locking mechanism to enable the first and second elongate members to be locked in at least a first predetermined position by a relative rotation of the first and second elongate members about their axis, to thereby prevent said relative longitudinal displacement of the catheter sleeves.

2. The adaptor of claim 1, wherein the first and second axial lumens are substantially co-axial when the first elongate member is engaged with the second elongate member.

3. The adaptor of claim 1 or claim 2. wherein the catheter engagement means is in the form of a third axial lumen, extending partially through, the second elongate member and defining an inner surface of the second elongate member for frictional coupling to the outer catheter sleeve.

4. The adaptor of claim 3. wherein the third axial lumen is co-axial with the second axial lumen.

5. The adaptor of claim 3 or claim 4, wherein the second axial lumen and the third axial lumen have different bore sizes.

6. The adaptor of claims 3 to 5. wherein the second axial lumen and the third axial lumen are separated by a first annular lip inside the second elongate member.

7. The adaptor of claim 6, wherein the first annular lip defines a central aperture having a bore size, in the region of the lip, which is smaller than the bore sizes of the second and third axial lumens.

8. The adaptor of claim 6 or claim 7, wherein the first annular lip is a rest for an abutting end wall of the outer catheter sleeve.

9. The adaptor of any preceding claim, further comprising at least one seal to inhibit leakage of fluid between an outer surface of the first portion of the first elongate member and an inner surface of the second elongate member defined by the second axial lumen.

10. The adaptor of claim 9, wherein the at least one seal is an O-ring seal located in a first circumferential recess on an outer surface of the first portion of the first elongate member.

11. The adaptor of claims 7 to 10, wherein the first annular lip is operable to exert a longitudinal compressional force on the outer catheter sleeve when the first and second elongate members are locked in the first predetermined open position.

12. The adaptor of an)' preceding claim, wherein the first elongate member further comprises a second portion defining a forth axial lumen therethrough, in fluid communication, and co-axial, with the first axial lumen.

13. The adaptor of claim 12, wherein the first axial lumen and fourth axial lumens have different bore sizes.

14. The adaptor of claim 12 or claim 13, wherein the first axial lumen and the fourth axial lumen are separated by a second annular lip inside the first elongate member.

15. The adaptor of claim 14, wherein the second annular lip defines a central aperture having a bore size, in the region of the lip. which is smaller than the bore sizes of the first and fourth axial lumens.

16. The adaptor of claim 14 or claim 15, wherein the second annular lip is a rest for an abutting end wall of the inner catheter sleeve.

17. The adaptor of any preceding claim, wherein the locking mechanism comprises at least one pin and at least one track, the track including at least a first locking slot position corresponding to a first circumferential portion of the track.

18. The adaptor of claim 17, wherein the at least one pin is located on an outer surface of the first portion of the first elongate member.

19. The adaptor of claim 17 or claim 18, wherein the at least one pin is adapted to engage the at least first locking slot position by said relative rotation of the first and second elongate members about their axis.

20. The adaptor of any of claims 17 to 19, wherein the at least one track is located in a portion of an outer surface of the second elongate member substantially overlying the at least one pin location, such that the pin engages with the track and is constrained to move within the track, such that the combination of the track and pin are operable to constrain the longitudinal displacement between the first and second elongate members

21. The adaptor of any preceding claim, further comprising an outer leakage bellows extendible along the axis of the second axial lumen, the bellows adapted, in use, to contain any leakage of fluid between an outer surface of the first portion of the first elongate member and an inner surface of the second elongate member defined by the second axial lumen.

22. The adaptor of claim 21, wherein the leakage bellows cover a portion of the outer surface of the second elongate member and are adapted to extend and contract with relative displacement of the first and second elongate members.

23. The adaptor of claim 21 or claim 22, wherein the outer leakage bellows enclose the locking mechanism.

24. The adaptor of claims 21 to 23, wherein the leakage bellows comprises first and second end walls, the first end wall being bonded to an outer surface of the first elongate member and the second end wall being bonded to the outer surface of the second elongate member, the bonding being resistive to fluid leakage.

25. The adaptor of any preceding claim, wherein the first axial lumen defines an inner surface of the first portion of the first elongate member for frictional coupling to an outer surface of the inner catheter sleeve.

26. The adaptor of claim 12, wherein the connecting means are attached to the second portion of the first elongate member.

27. The adaptor of claim 12 or claim 26, wherein the second portion includes a thread for threading engagement with the connecting means.

28. The adaptor of any preceding claim, wherein the connecting means are adapted for connection to standard medical connectors and/or receptacles.

29. The adaptor of any preceding claim, wherein at least part of an outer surface of the second elongate member is textured to improve grip.

30. The adaptor of claim 14, wherein at least part of an outer surface of the second portion of the first elongate member is textured to improve grip.

31. A urinary drainage system comprising a proximal end adaptor according to any preceding claim.

32. A catheter for providing fluid communication between a distal end and a proximal end of the catheter, comprising an inner sleeve and an outer sleeve, including the proximal end adaptor according to any of claims 1 to 31, integrally formed therewith.

33. Apparatus substantially as described herein with reference to the accompanying drawings.