Insertion tip for a catheter

Abstract

A catheter insertion tip (15) is described. The catheter insertion tip (15) comprises a hollow body (130) having at least one slit (158, 160) for a catheter tube (120) to exit an interior of the hollow body (130). The at least one slit (158, 160) defines at least two opposing sidewalls (156). The insertion tip (15) further comprises one or more transition zones (166) connecting one or more of the sidewalls (156) with an exterior (164) of the hollow body (130). The one or more transition zones (166) blunt an interface between the exterior of the hollow body (130) and the one or more of the sidewalls (156).

Description

[0001] Insertion Tip for a Catheter

[0002] Technical Field of the Invention

[0003] The present invention relates to a catheter assembly (e.g. an intermittent urinary catheter), and specifically an insertion tip of such an assembly.

[0004] Background to the Invention

[0005] A catheter is a medical device comprising a hollow catheter tube designed for insertion into canals, vessels, passageways or body cavities to permit injection, drainage or withdrawal of fluids or substances therefrom, or to ensure said canals, vessels, passageways etc. remain open. Urinary catheters are designed for use for insertion into a user’s bladder via the urethra to drain the bladder.

[0006] To assist in inserting the catheter tube into the urethra an insertion tip may be employed. The insertion tip generally includes a hollow body that in use is inserted into the urethra in a first step of a process of connecting the catheter tube to the user’s bladder. The catheter tube is then passed through an aperture (typically a cruciform slit) in the insertion tip and into the urethra of the user. The insertion tip remains in position within the user while the catheter tube is located in the urethra of the user. Use of insertion tips can reduce the number of urinary track infections by avoiding insertion of the catheter transferring bacteria from near the urethral meatus of the urethra along the urethra towards the bladder.

[0007] The slit of the insertion tip has sharp edges that cause the user discomfort when the insertion tip is inserted into the urethra. Often catheters need to be changed on a frequent basis (e.g. five times per day) and the user may be aware of the pain caused by the sharp edges of the insertion tip, causing them anxiety. This can lead to users choosing catheters without insertion tips.

[0008] It is a object of the present invention to mitigate or obvate at least one problem with prior insertion tips and their associated catheter assemblies.

[0009] Summary of the Invention

[0010] The present invention provides an insertion tip according to the appended claims.

[0011] A broad aspect of the present disclosure provides a catheter insertion tip. The tip may comprise a hollow body. The hollow body may have at least one slit for a catheter tube to exit an interior of the hollow body. The at least one slit may define at least two opposing sidewalls. The insertion tip may further comprise one or more transition zones connecting one or more of the sidewalls with an exterior of the hollow body.

[0012] According to another broad aspect of the present invention, there is provided a catheter insertion tip comprising: a hollow body having at least one slit for a catheter tube to exit an interior of the hollow body, the at least one slit defining at least two opposing sidewalls, wherein the insertion tip further comprises one or more transition zones connecting one or more of the sidewalls with an exterior of the hollow body.

[0013] The transition zones of the insertion tip of the present invention can avoid sharp edges on the insertion tip, meaning the insertion tip causes or at least will be perceived to cause the user less discomfort in use. As the insertion tip is, or may at least be perceived to be, far more comfortable for the user, the user is more likely to select a catheter having such a tip, meaning they experience the benefits associated with reduced bacterial displacement, resulting in less urinary tract infections. The one or more transition zones may define at least one valley in the hollow body. Accordingly, in an embodiment, there is provided a catheter insertion tip comprising: a hollow body having at least one slit for a catheter tube to exit an interior of the hollow body, the at least one slit defining at least two opposing sidewalls, wherein the insertion tip further comprises one or more transition zones connecting one or more of the sidewalls with an exterior of the hollow body, wherein the one or more transition zones define at least one valley in the hollow body.

[0014] The hollow body may comprise an end portion. The end portion may be a tapering end portion. “Tapering” in this specification means narrowing. The narrowing may be gradual or abrupt and may be straight, or more preferably round.

[0015] The tapering end portion may comprise the at least one slit. The exterior of the hollow body may be the exterior of the tapering end portion. The one or more transition zones may connect the one or more of the sidewalls with the exterior of the tapering end portion. Accordingly, in an embodiment, there is provided a catheter insertion tip comprising: a hollow body having at least one slit for a catheter tube to exit an interior of the hollow body, the at least one slit defining at least two opposing sidewalls, wherein the insertion tip further comprises one or more transition zones connecting one or more of the sidewalls with an exterior of the hollow body, wherein the hollow body comprises a tapering end portion, wherein the tapering end portion comprises the at least one slit, wherein the exterior of the hollow body is the exterior of the tapering end portion, wherein the one or more transition zones connect the one or more of the sidewalls with the exterior of the tapering end portion.

[0016] The tapering end portion may be a substantially hemispherical end portion. Accordingly, in an embodiment, there is provided a catheter insertion tip comprising: a hollow body having at least one slit for a catheter tube to exit an interior of the hollow body, the at least one slit defining at least two opposing sidewalls, wherein the insertion tip further comprises one or more transition zones connecting one or more of the sidewalls with an exterior of the hollow body, wherein the hollow body comprises a tapering end portion, wherein the tapering end portion comprises the at least one slit, wherein the exterior of the hollow body is the exterior of the tapering end portion, wherein the one or more transition zones connect the one or more of the sidewalls with the exterior of the tapering end portion, wherein the tapering end portion is a substantially hemispherical end portion of the hollow body.

[0017] The one or more transition zones may blunt an interface between the exterior of the hollow body and the one or more of the side walls.

[0018] Accordingly, in a first aspect of the invention, there is provided a catheter insertion tip comprising: a hollow body having at least one slit for a catheter tube to exit an interior of the hollow body, the at least one slit defining at least two opposing sidewalls, wherein the insertion tip further comprises one or more transition zones connecting one or more of the sidewalls with an exterior of the hollow body, whereby the one or more transition zones blunt an interface between the exterior of the hollow body and the one or more of the sidewalls. The one or more transition zones may be provided by one or more chamfers. The one or more chamfers may be straight or curved; i.e. the chamfer may comprise a “round” or a “radius”.

[0019] The one or more transition zones may define at least one valley in the hollow body. Accordingly, in an embodiment, there is provided a catheter insertion tip comprising: a hollow body having at least one slit for a catheter tube to exit an interior of the hollow body, the at least one slit defining at least two opposing sidewalls, wherein the insertion tip further comprises one or more transition zones connecting one or more of the sidewalls with an exterior of the hollow body, whereby the one or more transition zones blunt an interface between the exterior of the hollow body and the one or more of the sidewalls, wherein the one or more transition zones define at least one valley in the hollow body. The at least one valley may have straight or curved edges, i.e. it may be U-shaped or V-shaped. The at least one slit may be provided in at least one valley floor of the at least one valley. The one or more transition zones may define two intersecting valleys provided in the hollow body.

[0020] The insertion tip may have a centre.

[0021] The two intersecting valleys may be centred on the centre of the hollow body.

[0022] The transition zone may have a surface area in the range of 0.3 mm2to 14.2 mm2. The surface area may be in the range of 0.5 mm2to 12 mm2, or 1 mm2to 12 mm2, or 3 mm2to 12 mm2, or 4 mm2to 12 mm2, or 6 to 10 mm2.

[0023] The one or more transition zones may lack a sharp edge.

[0024] The one or more transition zones may be curved.

[0025] The one or more transition zones may be convex (when the tip is viewed from an external position). The one or more transitions zones may be concave (when the tip is viewed from an external position).

[0026] The one or more transition zones may comprise a concave part and a convex part. The convex part may extend to the concave part from the one or more sidewalls. The concave part may extend from the convex part to the exterior of the hollow body. The concave part may be concave when the tip is viewed from an external position. The convex part may be convex when the tip is viewed from an external position.

[0027] The one or more transition zones may extend around an outer perimeter of the at least one slit. In particular, the one or more transition zones may extend around a whole outer perimeter of the at least one slit.

[0028] The one or more transition zones may comprise a single transition zone. Alternatively, there may be multiple transition zones extending from different sidewalls defined by the at least one slit. The different transition zones may be separated.

[0029] The convex part of the single transition zone may surround the concave part of the single transition zone. The concave part may surround the at least one slit.

[0030] A first distance between the one of the sidewalls and the exterior of the hollow body across the single transition zone may be A. A may be a distance in the range of 0.001 to 30mm, or in the range of 0.001 to 20mm, or in the range of 0.01 to 20mm, or in the range of 0.05 to 20mm, or in the range of 0.1 mm to 20mm, or in the range of 1 to 20mm. A may be measured along a first most direct route (the most direct route between the one of the sidewalls and the exterior of the hollow body) between the one of the sidewalls and the exterior of the hollow body.

[0031] The one or more of the sidewalls may have a free end and a connected end connected to the single transition zone. The one or more of the sidewalls may extend between the free end and the connected end. A second distance between the free end and connected end may be B. B may be measured along a second most direct route (the most direct route between the free end and the connected end) between the free end and the connected end. A (the distance between the sidewall and the exterior of the body) may be in the range of 0.1 B to 10B, or in the range of 0.2B to 5B, or in the range of 0.4B to 2B. A may be greater than B. Alternatively, B may be greater than A.

[0032] The at least one slit may comprise at least two slits, and preferably the at least one slit comprises only two slits. Each slit may have a length that is greater than the diameter of the catheter tube. Each slit may have a length that is no more than 70%, 80% or 90% of the diameter of the tip. Each slit may have a length that is no less than 80%, 70% or 60%of the diameter of the tip. Preferably, each slit has a length of 70% of the diameter of the tip, for example 3-5 mm. Each slit may have substantially the same length. Thus, the slits can provide an effective seal without negatively effecting the structural integrity of the insertion tip.

[0033] One or more or each slit may be arranged to intersect at the centre of the insertion tip. One or more or each slit may extend from the centre of the insertion tip. One or more or each slit may terminate at substantially the same distance from the centre of the insertion tip. Where there are two or more slits, at least two slits, or each slit, may intersect. Where there are two or more slits, there may be two or more angles defined between adjacent slits. The two or more angles may all be substantially the same. The two slits (or at least two of the slits) may be arranged orthogonally. The two slits (or at least two of the slits) may be arranged in a cross. The cross may be centred on the centre of the insertion tip. Thus, the slits may be arranged to maximise the available space and ensure that the catheter passes through the middle of the insertion tip easily.

[0034] When there are two slits, the two slits may be provided in the valley floors of the intersecting valleys. In particular, in an embodiment, the one or more transition zones define two intersecting valleys centred on a centre of the insertion tip, wherein the at least one slit comprises intersecting slits centred on the centre of the insertion tip, wherein the intersecting slits are provided in valley floors of the intersecting valleys.

[0035] In some embodiments, the two or more angles between adjacent slits may be different, that is they may not be equal. For example, in one embodiment, two slits may be arranged in a T-shape to define three flaps. In another embodiment three slits may be arranged in a Y-shape to define three flaps.

[0036] The hollow body may comprise at least two flaps. The at least one slit may define the at least two flaps. The at least two flaps may be movable to allow the catheter to exit the hollow body. The at least two flaps may be separatable. The at least two flaps may be movable / separatable by the catheter to allow passage of the catheter through the insertion tip. The hollow body may comprise four flaps preferably defined by two slits. Thus, in use the catheter can be easily pass through the insertion tip via the flaps.

[0037] The four flaps may each comprise one or more free edges defined by the two slits. The thickness of each flap at the one or more free edges may be less than a maximum thickness of each flap. Preferably, each of the four flaps has two free edges defined by the two slits and the thickness of each flap at each free edge is less than the maximum thickness of each flap. The hollow body may comprise an end portion. The end portion may be a tapering end portion. “Tapering” in this specification means narrowing. The narrowing may be gradual or abrupt and may be straight, or more preferably round.

[0038] The tapering end portion may comprise the at least one slit. The exterior of the hollow body may be the exterior of the tapering end portion. The one or more transition zones may connect the one or more of the sidewalls with the exterior of the tapering end portion. The exterior of the tapering end portion may be one or more tapering external surfaces of the tapering end portion. Accordingly, in an embodiment, there is provided a catheter insertion tip comprising: a hollow body having at least one slit for a catheter tube to exit an interior of the hollow body, the at least one slit defining at least two opposing sidewalls, wherein the insertion tip further comprises one or more transition zones connecting one or more of the sidewalls with an exterior of the hollow body, whereby the one or more transition zones blunt an interface between the exterior of the hollow body and the one or more of the sidewalls, wherein the hollow body comprises a tapering end portion, wherein the tapering end portion comprises the at least one slit, wherein the exterior of the hollow body is the exterior of the tapering end portion, wherein the one or more transition zones connect the one or more of the sidewalls with the exterior of the tapering end portion.

[0039] The tapering end portion may be a substantially hemispherical end portion. Accordingly, in an embodiment, there is provided a catheter insertion tip comprising: a hollow body having at least one slit for a catheter tube to exit an interior of the hollow body, the at least one slit defining at least two opposing sidewalls, wherein the insertion tip further comprises one or more transition zones connecting one or more of the sidewalls with an exterior of the hollow body, whereby the one or more transition zones blunt an interface between the exterior of the hollow body and the one or more of the sidewalls, wherein the hollow body comprises a tapering end portion, wherein the tapering end portion comprises the at least one slit, wherein the exterior of the hollow body is the exterior of the tapering end portion, wherein the one or more transition zones connect the one or more of the sidewalls with the exterior of the tapering end portion, wherein the tapering end portion is a substantially hemispherical end portion.

[0040] The hemispherical end portion may be for inserting into a passageway in the patient. The at least one slit may be provided in the hemispherical end portion. In particular, the two slits arranged in a cross may be provided in the hemispherical end portion. The cross may be centred on the centre of the hemispherical end portion.

[0041] The insertion tip may comprise at least one flange that projects outwardly from the hollow body. The at least one flange may project outwardly from the hollow body in a radial direction. The at least one flange may comprise two flanges. The flanges may project from the hollow body from positions that are diametrically opposed to each other.

[0042] The catheter insertion tip may be for a urinary catheter assembly. The catheter insertion tip may be for an intermittent urinary catheter assembly. The catheter insertion tip may be for a female intermittent urinary catheter assembly. The catheter insertion tip may be for a male intermittent urinary catheter assembly. The exterior of the hollow body may be one or more external surfaces of the hollow body that face away from the hollow body.

[0043] The insertion tip may be formed from a synthetic material. The synthetic material may comprise a plastics material. The plastics material may comprise a thermoplastic elastomer (TPE). The plastics material may comprise polyethylene or polystyrene. Alternatively, the plastics material may comprise a blend of polyethylene and polystyrene. This blend is advantageous in the context of the insertion tip because it provides a particularly good seal around the catheter tube in use, thus preventing microbial displacement.

[0044] The blend of polyethylene and polystyrene may have a Shore Hardness Scale A (HA) value in the range of 94 to 80, 92 to 82, 91 to 83, or 89 to 85. Most preferably, the blend has a HA of 87. The HA may be obtained via the ISO 868:2003 (reviewed and confirmed in 2018 and current as of 4 October 2023).

[0045] When the plastics material is polyethylene, the polyethylene may have a Shore Hardness D value (HD) in the range of 35 to 45. The HD of the polyethylene may be in the range of 36 to 44, 37 to 43, 38 to 42, or 39 to 41. Most preferably, the HD of the polyethylene is 40. The HD may be measured using an ISO 868:2003 (reviewed and confirmed in 2018 and current as of 4 October 2023).

[0046] The insertion tip may comprise an entrance opening for the catheter to enter the insertion tip. The entrance opening may be located opposite the at least one slit. The insertion tip may be tubular. The entrance opening may be at one end of the tubular insertion tip and the at least one slit may be at the opposite end. The entrance opening may be provided at a first end of the insertion tip and the end portion comprising the at least one slit may be provided at a second end of the insertion tip opposite the first end.

[0047] The at least two opposing sidewalls are configured to move from a first position where they abut each other to a second position where they are separated by the catheter tube (as the catheter tube is advanced through, and out of the insertion tip). This structure is advantageous in preventing microbes moving up the urethra in use.

[0048] According to a second aspect of the present invention, there is provided a catheter assembly comprising: a catheter insertion tip according to the first aspect; and a catheter tube.

[0049] Optionally, the catheter assembly may comprise a housing defining a wetting chamber. The housing may be part of a sub-assembly including the insertion tip.

[0050] The catheter assembly may be a urinary catheter assembly.

[0051] The catheter assembly may be provided in a sterile package.

[0052] Optional features set out above with respect to each aspect of the invention may apply to any other aspect of the invention.

[0053] Detailed Description of the Invention

[0054] In order that the invention may be more clearly understood one or more embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which:

[0055] Figure 1 shows a perspective view of a catheter assembly according to an embodiment of the disclosure;

[0056] Figure 2 shows a longitudinal sectional view of the catheter assembly of Figure 1 ; Figure 3 shows an insertion tip and internal housing of the catheter assembly of Figure 1;

[0057] Figure 4 shows a hemispherical end portion of the insertion tip of Figure 3 in greater detail;

[0058] Figure 5 shows the hemispherical end portion of the insertion tip of Figure 3 rotated slightly with respect to its position in Figure 4;

[0059] Figure 6 shows a sectional view of the insertion tip of Figure 3;

[0060] Figure 7 shows a detail view of a portion of the section shown in Figure 6; and

[0061] Figure 8 shows a graph depicting the improved bacterial displacement associated with insertion tips of the invention.

[0062] Referring to figures 1 and 2, the catheter assembly 1 comprises an external housing 10, a cap 40, a sheath 80 and a catheter 120. The catheter assembly 1 may optionally be configured such that the catheter 120 may be wetted prior to being withdrawn from the external housing 10. A wetting mechanism may be provided within the external housing 10.

[0063] The external housing or catheter assembly body 10 has a tubular shape with a radially outer surface 8, a radially inner surface 9, an open cap end 11 and an open catheter end 12. The outer surface 8 of the external housing comprises a textured portion 13 to improve grip, in this embodiment provided by a plurality of ribs extending circumferentially around and radially outward of the outer surface 8. The textured portion 13 extends from the cap end 11 to the catheter end 12. In some embodiments the textured portion 13 may be integrally formed with the outer surface 8, in other embodiments the textured portion 13 may be formed of a different material, for example one which provides increased grip when wet.

[0064] Within the external housing 10 and projecting from open ends of the assembly body 10 is an inserter 14, the inserter having an overall tubular shape and comprising an insertion tip 15, a substantially tubular body 17 and a catheter gripper 16. The insertion tip will be described in greater detail below. The external housing 10 and inserter 14 are concentrically arranged such that the inserter 14 is located within the external housing 10 in a radially nested configuration. The insertion tip 15 is provided at a first end of the tubular body 17 and closes the tubular body with tapering end portion 15a. In the depicted example, the tapering end portion 15a is a hemispherical end portion. The hemispherical end portion 15a is provided with one or more slits (not shown) which allow the hemispherical end portion 15a to be opened to allow passage of a catheter therethrough. The opposite end of the inserter 14 is provided with the catheter gripper 16.

[0065] In this embodiment the inserter 14 is arranged within the external housing 10 such that in the storage position the insertion tip 15 extends out of the cap end 11 and the catheter gripper 16 extends out of the catheter end 12 of the external housing 10.

[0066] In this embodiment the cap 40 is formed in two parts, a connecting part 41 and a removable part 50. The connecting part 41 has an annular shape with an aperture 42 through the centre, it is connected to the cap end 11 of the external housing 10. The removable part 50 has a tubular shape with an open end 51 and a closed end 52, the interior of the removable part 50 defines a cavity 53 shaped to receive the insertion tip 15. The cavity may be sized and shaped to closely conform to the insertion tip 15. The exterior of the removable part 50 is shaped to engage with the aperture 42 in the connecting part 41. On the exterior of the removable part 50 at the closed end 52 there is provided a grab loop 54 by which a user can grip the cap 40. The two parts 41,50 of the cap 40 are connected together by a retaining strap 45.

[0067] The catheter 120 is of a type known to the art, comprising a catheter tube 121 with an insertion end 122 and an opposing drainage end (not shown). The catheter tube 121 has a longitudinal axis A-A which can be taken to be the principal axis of the catheter assembly 10. Proximate to the insertion end 122 there may be provided one or more drainage apertures 133, in this embodiment the drainage apertures 133 are oval in shape with the major axis being parallel with the principal axis A-A. It will be appreciated that the size and shape of the drainage apertures 133 may differ.

[0068] The exterior surface of the catheter tube 121 may be, as is known in the art, functionalised such that when wetted by the wetting agent the co-efficient of friction of the catheter tube 121 is reduced. The outer surface of the catheter tube 121 may be comprised of, or coated in, a functionalising material; for example the outer surface of the catheter tube 121 may have hydrophilic properties. The hydrophilic properties serve to reduce the coefficient of friction of the outer surface when the wetting agent is introduced.

[0069] The catheter 120 and inserter 14 are concentrically arranged such that the insertion end 122 of the catheter 120 engages with the catheter gripper 16 with the distal end of the catheter 120 extending away from the inserter 14 as will be described in further detail below.

[0070] Arranged at the catheter end 12 of the external housing 10 is the sheath 80. The sheath 80 extends away from the external housing 10 so as to surround at least a part of the catheter tube 120. The sheath 80 is formed of a flexible material. In some embodiments, the sheath 80 is attached to the external housing in such a way as to provide a leak resistant seal. In some embodiments the distal end of the sheath (not shown) may be joined to a pouch for collection of the fluid discharged from the catheter, alternatively the sheath 80 and pouch may be integrally formed. The sheath may allow for fluid communication from the external housing 10 to the pouch.

[0071] Turning now to Figures 3 to 7, the insertion tip 15 is shown in greater detail. The insertion tip 15 is shown integrally formed with the tubular body 17. However, it should be understood that the insertion tip can be provided as a separate element unattached to another element (like a tubular body defining a wetting chamber). The insertion tip 15 is also substantially tubular and comprises a hollow body 130 with a tapering end portion 15a. The tapering end portion 15a may be considered to be a narrowing end portion. The tapering (or narrowing) of the end portion 15a may be gradual or abrupt. In the depicted example, the tapering end portion 15a is a hemispherical end portion 15a, although it is envisioned that other tapering shapes could be employed such as a conically shaped end portion. This hemispherical end portion 15a is configured for insertion into a user. The hemispherical end portion 15a comprises an arrangement of one or more slits 158, 160 which allow a catheter to exit an interior 134 (as best shown in Figure 6) of the hollow body 130. At an opposite end 136 of the insertion tip 15 an entrance opening (not visible in Figures 3 to 7) for the catheter is provided. The entrance opening allows the catheter to access the interior of the hollow body so it can pass therethrough to exit the insertion tip 15 via the arrangement of slits 158, 160. The insertion tip is formed from a synthetic material such a plastics material. The plastics material may comprise a thermoplastic elastomer (TPE). In some embodiments, the plastics material may comprise polyethylene or polystyrene. When the plastics material is polyethylene, the polyethylene may have a Shore Hardness D value (HD) of 40. The HD may be measured using an ISO 868:2003 (reviewed and confirmed in 2018 and current as of 4 October 2023). Alternatively, in other embodiments, the plastics material may comprise a blend of polyethylene and polystyrene. This blend is advantageous in the context of the insertion tip because it provides a particularly good seal around the catheter tube in use, thus preventing microbial displacement. The blend of polyethylene and polystyrene may have a Shore Hardness Scale A (HA) value of 87. The HA may be obtained via the ISO 868:2003 (reviewed and confirmed in 2018 and current as of 4 October 2023).

[0072] As best shown in Figure 3, the insertion tip comprises two diametrically opposed flanges 152 that project outwardly from the hollow body 130 in a radial direction. The hollow body 130 depicted tapers slightly from the flanges 152 to the hemispherical end portion 15a.

[0073] Turning now to Figures 4 and 5, the arrangement of slits 158, 160 is shown in greater detail. In the example depicted, there are two slits 158, 160 (although there could only be a single slit) that are arranged to intersect each other at a centre point 154 of the hollow body so as to form a cross, although other arrangements are envisioned. For example, rather than the slits 158, 160 being orthogonally arranged as depicted, the slits could be arranged in a Saltire / St. Andrews cross-like arrangement, where there are both obtuse and acute angles between the slits. In the example depicted, the sidewalls of the slits 158, 160 abut each other until they are separated by the catheter tube in use as the catheter rube is advanced through the insertion tip 15.

[0074] In the depicted example, the hollow body 130 comprises four flaps 151 provided in the hemispherical end portion 15a and the slits 158, 160 are cut in the hollow body 130 to define those flaps. The flaps 151 assist the insertion tip in providing a seal around the catheter in use.

[0075] Each of the slits 158, 160 define opposing sidewalls 156. The opposing sidewalls 156 are connected by substantially U-shaped connecting walls (these U-shaped walls are very small so are difficult to see in Figures 4 and 5). In Figures 4 and 5, the slits 158, 160 comprise first and second intersecting slits 158, 160, each having opposing sidewalls 156. Only the top edges of the opposing sidewalls 156 are visible in Figures 4 and 5. Opposing sidewalls 156 of the first slit 158 are shown in greater detail in Figure 6 below.

[0076] Figure 6 shows a sectional view of the insertion tip 15 which is taken along the length of the first slit 158 and through a centre of the hollow body 130. The opposing sidewalls 156 on one side of the first slit 158 are shown in Figure 6. The opposing sidewalls 156 on the depicted side of the first slit 158 are separated by the second slit 160.

[0077] Referring back to Figures 4 and 5, each of the opposing sidewalls 156 is connected with an exterior 164 of the hollow body 130 by a transition zone 166 that extends around an outer perimeter of the first and second slits 158, 160. The exterior 164 of the hollow body 130 is made up of one or more external surfaces of the hollow body 130. In the depicted example, the exterior 166 of the hollow body is the exterior of the hemispherical end portion 15a and the transition zone 166 connects the opposing sidewalls 156 with the exterior of the hemispherical end portion 15a.

[0078] The transition zone 166 blunts an interface between the exterior of the hollow body and the one or more of the sidewalls. This means there are no sharp edges on the insertion tip meaning the insertion tip causes the user less discomfort in use.

[0079] The depicted transition zone 166 is curved (although it could be made up of opposing chamfered portions which could have straight surfaces). The transition zone 166 is made up of a concave part 168 and a convex part 170. The concave part 168 extends from the sidewalls to the convex part 170, which extends from the concave part 168 to the exterior of the hollow body 130. In the example depicted, the concave part 168 surrounds the first and second slits 158, 160 and the convex part 170 surrounds the concave part 168.

[0080] As best shown in Figure 7 (which shows a partial view of the hollow body at a crown of the hemispherical end), the transition zone 166 is a surface area 164 which is provided between the opposing sidewalls of the slits 158, 160 and the exterior of the hollow body 130. The transition zone 166 means that the insertion tip does not present sharp edges to the user which can cause them discomfort. A first distance between one of the opposing sidewalls 156 and the exterior of the hollow body 130 across the single transition zone 166 may be defined as “A”, where A is measured along a first most direct route (the most direct route between the one of the sidewalls and the exterior of the hollow body) between the one of the sidewalls and the exterior of the hollow body. A may be in the range of 0.001 to 30mm, or in the range of 0.001 to 20mm, or in the range of 0.01 to 20mm, or in the range of 0.05 to 20mm, or in the range of 0.1 to 20mm, or in the range of 1 to 20mm. Each opposing sidewall 156 extends between a free end 172 and a connected end 174 thereof. The free end 172 is provided in the interior of the body and the connected end 174 is connected to the transition zone 166. A second distance between the free end and connected end may be defined as “B”, where B is measured along a second most direct route (the most direct route between the free end and the connected end) between the free end and the connected end. A (the distance between the one of the sidewalls and the exterior of the body) may be in the range of 0.1 B to 1 OB, or in the range of 0.2B to 5B, or in the range of 0.4B to 2B. In the depicted example the first distance is slightly greater than the second distance (as Figure 7 shows a section view and the transition zone 166 is curved). In other words, A is greater than B.

[0081] As best shown in Figure 6, in the depicted example, each flap 151 has two free edges 181. A thickness of each flap 151 at the free edges 181 is greater than a maximal thickness of each flap. In other words, each of the flaps 151 narrows towards the free edges 181 of each flap 151.

[0082] As best shown in Figure 4, the transition zone 166 defines intersecting valley portions in the hollow body 130 and the slits 158, 160 are provided in the valley floors of those valley portions. The valley portions 166 also form a cross like the intersecting slits 158, 160 and define substantially U-shaped valleys, although valleys with other crosssections are envisioned (such as V-shaped valleys).

[0083] The transition zone 166 depicted is provided by a single chamfer extending around the outer perimeter of the slits 158,160. The particular chamfer of the specific example depicted is curved or “radiused” with a convex portion as described, in addition to a concave portion.

[0084] The transition zones of the insertion tip of the present invention can avoid sharp edges on the insertion tip, meaning the insertion tip causes or at least will be perceived to cause the user less discomfort in use. As the insertion tip is, or may at least be perceived to be, far more comfortable for the user, the user is more likely to select a catheter having such a tip, meaning they experience the benefits associated with bacterial displacement, resulting in less urinary tract infections.

[0085] It should be understood that the insertion tip of the present invention is applicable to a multitude of different catheter assemblies and may be supplied with or without a wetting chamber. In particular, it should be noted the insertion tip may not be supplied with a wetting chamber as described with reference to Figures 1 and 2 above. It should be noted that although above a specific example of an insertion tip in accordance with the present invention is described with a single transition zone extending around the outer perimeter of the at least one slit, there could equally be multiple transition zones extending from multiple slit sidewalls around the perimeter of the at least one slit.

[0086] It should be understood that the insertion tip may be for an intermittent urinary catheter assembly, a female intermittent urinary catheter assembly or a male intermittent urinary catheter assembly.

[0087] The one or more embodiments are described above by way of example only. Many variations are possible without departing from the scope of protection afforded by the appended claims.

[0088] With reference to Figure 8, there is shown a graph depicting the results of tests assessing the effectiveness of various insertion tips (including insertion tips of the present invention) at preventing bacterial displacement along a simulated urethra from a simulated urethral meatus. Bacterial prevalence (measured in CFU / ml) is on the Y-axis, whereas section distance along a simulated catheter (measured in cm) is on the X-axis.

[0089] The ML1.1 and ML1.2 tips are insertion tips in accordance with the present invention, whereas the other insertion tips are not in accordance with the present invention.

[0090] The “Closed Structure Tip” is a commercially available tip with a closed structure (a tip which has a relatively small or no gap between opposing sidewalls of the catheter slit arrangement before the tip receives the catheter tube). The “Closed Structure Tip” is market leading in terms of preventing bacterial displacement but has sharp edges where the sidewalls of its slit arrangement meet the exterior of the tip in contrast to the present invention.

[0091] The “Open Structure Tip” is a commercially available tip with an open structure (i.e. a tip which has a relatively large gap between opposing sidewalls of the catheter slit arrangement before the tip receives the catheter tube).

[0092] As shown the ML 1.1 and ML 1.2 tips are more effective at preventing bacterial displacement than the “Open Structure Tip”. The structure of the insertion tip of the present invention is therefore advantageous over prior open structure tips.

[0093] Testing Procedure The testing procedure in which the results used to generate the graph shown in Figure 8 were obtained will now be described.

[0094] The following sample insertion tips were tested:

[0095] - ML 1.1 (soft insertion tip material) with 1ml hydration

[0096] - ML 1.2 (hard insertion tip material) with 1ml hydration

[0097] - Commercially Available Closed Structure Tip with 1ml hydration

[0098] - Commercially Available Open Structure Tip with 1ml hydration

[0099] The ML 1.1 and ML 1.2 insertion tips are insertion tips in accordance with the present invention. The remaining insertion tips are not in accordance with the present invention.

[0100] The bacterial displacement testing procedure simulated the transfer of bacteria from the urethral meatus (which is colonised with microorganisms), during insertion of an intermittent catheter and how they travel along the urethra potentially to the bladder. This transfer of bacteria being a source of infection that can lead to urinary tract infections. Escherichia coli NCIMB 14067 was used as the challenge organism.

[0101] Samples

[0102] Sample Description

[0103] GentleCath™ Air for Men / set soft material catheter, CH12 male (convatec #ML1.1)

[0104] GentleCath™ Air for Men / set hard material catheter, CH12 male (convatec #ML1.2)

[0105] Commercially Available Closed Structure Tip

[0106] Commercially Available Open Structure Tip

[0107] Materials

[0108] Microbiological Media

[0109] Pre-dried Tryptone Soy Agar (TSA) Plates

[0110] Molten Harlequin Tryptone Bile Glucuronide (TBX) Agar + 0.4% Agar Bacteriological (AB) Maximum Recovery Diluent (MRD)

[0111] Dey-Engley Neutralising Broth (DENB)

[0112] Sterile Deionised Water (SDW)

[0113] Other Materials

[0114] 1ml Syringe

[0115] Sterican needle (206 0.9 x 70mm)

[0116] Swab

[0117] Flocked Swab

[0118] Swann-Morton Disposable Scalpel

[0119] Challenge Organisms

[0120] Escherichia coli NCIMB 14067

[0121] Test Method

[0122] Testing was performed using n=3 replicates for each catheter for TVCs and n=l for visual displacement images.

[0123] UAC preparation:

[0124] Selective agar channels were made by aseptically dispensing 30ml of molten Harlequin TBX agar + 0.4% AB (a selective agar for E. coli NCIMB 14067) into 30ml universal containers. Sterile 4mm stainless steel rods, held in place by sterile stainless steel locating discs, were placed into the universal containers and removed once set to create a channel down the centre of the agar the same diameter as CH12 catheters. The channels were left standing, with their lids removed, within the laminar flow cabinet to dry for 18- 24 hours. Additionally, to prepare the channels, just before testing, any fluid within the agar channel was removed using a sterile needle and syringe, a sterile swab was then inserted slowly (around 3 seconds) down the length of the channel, rotated anticlockwise twice at the base of the channel and slowly removed. These represented the urethra agar channels (UACs) for the testing. The UACs are simulated urethras.

[0125] Challenge organism preparation: Representative colonies from an 18-24 hour challenge culture plate, were dispersed in MRD to obtain an optical density (OD540nm) equivalent to approximately 1x108 CFU / ml. This was diluted ten-fold to obtain a working concentration of 1x107 CFU / ml. 50ml volumes of this working concentration were transferred into separate bijous for inoculation.

[0126] UAC inoculation:

[0127] A sterile Flocked swab was placed into the 50 ml inoculum of the above working concentration and left to sit for 10 seconds, the inoculated swab was then inserted 1cm into the insertion entrance of the UAC, rotated anticlockwise twice and removed. This was performed for all the test and bacterial growth control UACs. The inoculated UACs were then left lying horizontally with the lid off and the open, inoculated end facing the flame to dry for 15 minutes. The bacterial growth control image UAC was incubated at 35±3°C for 24 hours after inoculation and the bacterial growth control TVC UAC was immediately tested as stated below.

[0128] Testing performed:

[0129] The same procedure was performed on each insertion tip and a positive control. In particular, each sample was hydrated with 1ml SDW (by gently inserting a needle through the sleeve near the tip of the catheter and syringing 1ml SDW into the sleeve), the lid was removed from the insertion tip (if the insertion tip didn’t pull out correctly as required, sterile forceps were used to gently pull the tip out and into place) and tested immediately, as stated below.

[0130] UAC processing following testing for visual displacement images:

[0131] The catheter was slowly inserted (around 3 seconds) and left in place for 2 minutes to represent urination. Following insertion and removal of the catheter and a 15-minute drying time, the UACs were incubated at 35±3°C for 24 hours. Following incubation, the UACs were aseptically tipped from the container onto a sterile surface and under aseptic conditions the UACs were split in half lengthways. The two halves of the UACs were then separated so the inside of the channels were visible and growth of the bacteria was therefore also visible, images were taken to observe the bacteria’s displacement through the UACs.

[0132] UAC processing following testing for Total viable counts (TVCs): The catheter was slowly inserted (around 3 seconds) and left in place for 2 minutes to represent urination. Following insertion and removal of the catheter and a 15-minute drying time, the UACs for TVCs were aseptically tipped from the universal and cut into 7x 1cm sections starting at the insertion entry of the UAC. The 1st, 3rd, 5th and 7th cm were stomached on high for 4 minutes in DENB and plated out onto TSA plates in appropriate dilutions. Plates were incubated at 35±3°C for 48 hours.

[0133] Data / Results

[0134] The results of the above testing are shown in the graph of Figure 8. As shown, the tips of the present invention (the ML 1.1 and ML 1.2 tips) were much better at preventing bacteria moving along a UAC than the Open Structure Tip tested.

Claims

Claims:

1. A catheter insertion tip comprising: a hollow body having at least one slit for a catheter tube to exit an interior of the hollow body, the at least one slit defining at least two opposing sidewalls, wherein the insertion tip further comprises one or more transition zones connecting one or more of the sidewalls with an exterior of the hollow body, whereby the one or more transition zones blunt an interface between the exterior of the hollow body and the one or more of the sidewalls.

2. The insertion tip of claim 1 , wherein the one or more transition zones extend around an outer perimeter of the at least one slit.

3. The insertion tip of any preceding claim, wherein the one or more transition zones define at least one valley in the hollow body.

4. The insertion tip of any preceding claim, wherein the one or more transition zones are provided by one or more chamfers.

5. The insertion tip of claim 4, wherein the one or more chamfers are curved.

6. The insertion tip of claim 4, wherein the one or more chamfers are straight.

7. The insertion tip of any preceding claim, wherein the one or more transition zones have a surface area in the range of 0.3 mm2to 14.2 mm2.

8. The insertion tip of any preceding claim, wherein the one or more transition zones lack a sharp edge.

9. The insertion tip of any preceding claim, wherein the one or more transition zones are curved.

10. The insertion tip of any preceding claim, wherein the one or more transition zones are convex.

11. The insertion tip of any preceding claim, wherein the one or more transitions zones are concave.

12. The insertion tip of any preceding claim, wherein the one or more transition zones comprise a concave part and a convex part.

13. The insertion tip of claim 12, wherein the convex part extends to the concave part from the one or more of the sidewalls and the concave part extends from the convex part to the exterior of the hollow body.

14. The insertion tip of any preceding claim, wherein the one or more transition zones comprise a single transition zone.

15. The insertion tip of claim 14 when claim 14 is dependent upon claim 13, wherein the convex part of the single transition zone surrounds the concave part of the single transition zone, wherein the concave part surrounds the at least one slit.

16. The insertion tip of claim 14 or 15, wherein a first distance between the one of the sidewalls and the exterior of the hollow body across the single transition zone is A, preferably A is in the range of 0.001 to 30mm17. The insertion tip of claim 16, wherein the one or more of the sidewalls has a free end and a connected end connected to the single transition zone, wherein the one or more of the sidewalls extends between the free end and the connected end, wherein a second distance between the free end and connected end is B, wherein A is in the range of 0.1B to 10B.

18. The insertion tip of any preceding claim, wherein the at least one slit comprises at least two slits arranged to intersect at a centre of the insertion tip.

19. The insertion tip of claim 18, wherein the at least two slits comprise two slits arranged in a cross.

20. The insertion tip of any preceding claim, wherein the hollow body comprises a tapering end portion, wherein the tapering end portion comprises the at least one slit, wherein the exterior of the hollow body is the exterior of the tapering end portion, wherein the one or more transition zones connect the one or more of the sidewalls with the exterior of the tapering end portion.

21. The insertion tip of claim 20, wherein the tapering end portion is a substantially hemispherical end portion of the hollow body.

22. The insertion tip of any preceding claim, wherein the insertion tip is formed from a synthetic material.

23. The insertion tip of claim 22, wherein the synthetic material comprises a plastics material.

24. The insertion tip of claim 22 or 23, wherein the plastics material comprises a blend of polyethylene and polystyrene.

25. A catheter assembly comprising: the catheter insertion tip of any preceding claim; and a catheter tube.

Images