A Catheter Assembly
Technical Field of the Invention
The present invention relates to a urinary catheter assembly which is configured to aid flushing of the urethra in use.
Background to the Invention
Urinary catheter assemblies (also referred to as urinary catheters) for draining urine from the bladder may be indwelling or intermittent and are used to drain urine from a bladder. Intermittent catheters are typically used by patients suffering from urinary incontinence or by disabled individuals several times a day to drain the bladder as required.
It is relatively common for users of intermittent catheters to develop urinary tract infections or other complications. In some cases, this is because intermittent catheters typically comprise a closed lumen which expels urine from the bladder without it contacting the urethra wall. As such, there can be a persistent build up of bacteria and debris (e.g., skin cells or excretions) which would otherwise be flushed out by the urine.
WO2012/85124 describes an intermittent urinary catheter comprising an elongate shaft with an insertion end, a handle connected to the elongate shaft at a distance from the insertion end, and a discharge end extending past the handle in a direction opposite the insertion end. The elongate shaft is provided with at least one discharge channel having an elongate opening extending along the elongate shaft. The discharge channel includes an opening against which a flow of urine can contact the urethra in use to aid with flushing of the urethra. In use, a user holds the handle and urine flows down the exterior of the shaft all the way to its discharge end tip, from which it is discharged.
The present invention seeks to provide an improved catheter for flushing the urethra in use.
Summary of the Invention
The present disclosure provides a catheter according to the appended claims. The present disclosure provides, in a broad aspect, an intermittent urinary catheter assembly. The intermittent urinary catheter assembly may comprise: an elongate main body and a funnel. The elongate main body may have an insertion end for insertion into a urethra and bladder. The elongate main body may have an outlet end for the outflow of fluid from the catheter. The elongate main body may have an external flushing portion. The external flushing portion may extend between the insertion end and the outlet end. The external flushing portion may comprise at least one flushing channel. The funnel may be attached to the outlet end of the elongate main body. The intermittent urinary catheter assembly preferably comprises a gripper extending away from a longitudinal axis of the elongate main body.
The present disclosure provides, in a first aspect, an intermittent urinary catheter assembly comprising: an elongate main body and a funnel, the elongate main body having an insertion end for insertion into a urethra and bladder, an outlet end for the outflow of fluid from the catheter, and an external flushing portion extending between the insertion end and the outlet end, wherein the external flushing portion comprises at least one flushing channel, wherein the funnel is attached to the outlet end of the elongate main body, and further comprises a gripper extending away from a longitudinal axis of the elongate main body.
As compared to WO2012/85124, providing a funnel at the end of the catheter can provide for more hygienic handling of the catheter, because once the urine reaches the funnel, it will flow inside the funnel, and as such there is a part of the catheter assembly (the funnel) which can maintain a clean external surface. Moreover, providing the funnel with a gripper extending away from a longitudinal axis of the elongate main body is particularly advantageous in providing hygienic handling of the catheter as it allows a user to hold the gripper at a distance from the elongate main body such that the user’s hand does not risk contacting the flow of urine in use. This is particularly beneficial in the context of a urinary catheter with an external flushing channel, as compared to a conventional urinary catheter with an internal channel through which urine flows, which would not have urine on its external surface. Providing the gripper extending away from a longitudinal axis of the elongate main body facilitates handling of the catheter assembly during insertion, removal, and directing the stream of urine in use. This may be particularly advantageous for disabled users with reduced manual dexterity.
The funnel may be directly attached to the outlet end of the elongate main body.
One particularly preferred embodiment provides an intermittent urinary catheter assembly comprising: an elongate main body and a funnel, the elongate main body having an insertion end for insertion into a urethra and bladder, an outlet end for the outflow of fluid from the catheter, and an external flushing portion extending between the insertion end and the outlet end, wherein the external flushing portion comprises at least one flushing channel, wherein the funnel is directly attached to the outlet end of the elongate main body, and further comprises a gripper extending away from a longitudinal axis of the elongate main body.
The gripper may extend perpendicularly away from a longitudinal axis of the elongate main body. For example, the gripper may extend away from the longitudinal axis in a plane perpendicular to the longitudinal axis. The gripper may extend perpendicularly away from a longitudinal axis of the elongate main body by a maximum distance of at least 10, 15, 17.5, 20, 21, 22 or 25mm. The gripper may extend perpendicularly away from a longitudinal axis of the elongate main body by a maximum distance of no more than 50, 40, 35, 30, 25, 24 or 23mm. The gripper may extend perpendicularly away from a longitudinal axis of the elongate main body by a maximum distance in the range of 15 mm to 50 mm. The gripper may extend perpendicularly away from a longitudinal axis of the elongate main body by a maximum distance in the range of 17.5 mm to 40 mm. The gripper may extend perpendicularly away from a longitudinal axis of the elongate main body by a maximum distance in the range of 20 mm to 35 mm. In a preferred embodiment, the gripper may extend perpendicularly away from a longitudinal axis of the elongate main body by a maximum distance of 22 mm. The gripper may alternatively extend tangentially away from a longitudinal axis of the elongate main body. Additionally or alternatively, the gripper may extend along a plane tangential to any point on an outer diameter of the elongate main body. Additionally or alternatively, the gripper may extend along a plane tangential to the longitudinal axis at a spaced distance away from the longitudinal axis.
Those skilled in the art will appreciate that the longitudinal axis of a catheter extends between the inlet end and the outlet end of the elongate main body. The longitudinal axis will typically extend along the centre of the elongate main body.
The gripper may be solid. The gripper may comprise a pair of opposed grip surfaces. The pair of opposed grip surfaces may be parallel to each other. The pair of opposed grip surfaces may be planar. The pair of opposed grip surfaces may be connected via a first connecting surface which may extend from a distal end of the funnel. The pair of opposed grip surfaces may be connected via a second connecting surface which may be connected to a free end of the first connecting surface. The pair of opposed grip surfaces may be connected via the first connecting surface which may extend from a distal end of the funnel, and the second connecting surface which may be connected to a free end of the first connecting surface. The second connecting surface may have a curved shape. The first connecting surface and the second connecting surface may have an equal and constant width. The second connecting surface may be connected to a proximal end of the funnel.
Another particularly preferred embodiment provides an intermittent urinary catheter assembly comprising: an elongate main body and a funnel, the elongate main body having an insertion end for insertion into a urethra and bladder, an outlet end for the outflow of fluid from the catheter, and an external flushing portion extending between the insertion end and the outlet end, wherein the external flushing portion comprises at least one flushing channel, wherein the funnel is attached to the outlet end of the elongate main body, and further comprises a gripper extending away from a longitudinal axis of the elongate main body, wherein the gripper comprises a pair of opposed grip surfaces and, wherein the pair of opposed grip surfaces are connected by a first connecting surface which extends from a distal end of the funnel.
Another particularly preferred embodiment provides an intermittent urinary catheter assembly comprising: an elongate main body and a funnel, the elongate main body having an insertion end for insertion into a urethra and bladder, an outlet end for the outflow of fluid from the catheter, and an external flushing portion extending between the insertion end and the outlet end, wherein the external flushing portion comprises at least one flushing channel, wherein the funnel is attached to the outlet end of the elongate main body, and further comprises a gripper extending away from a longitudinal axis of the elongate main body, wherein the gripper comprises a pair of opposed grip surfaces and, wherein the pair of opposed grip surfaces are connected by a first connecting surface which extends from a distal end of the funnel, and a second connecting surface which is connected to a free end of the first connecting surface.
Another particularly preferred embodiment provides an intermittent urinary catheter assembly comprising: an elongate main body and a funnel, the elongate main body having an insertion end for insertion into a urethra and bladder, an outlet end for the outflow of fluid from the catheter, and an external flushing portion extending between the insertion end and the outlet end, wherein the external flushing portion comprises at least one flushing channel, wherein the funnel is attached to the outlet end of the elongate main body, and further comprises a gripper extending away from a longitudinal axis of the elongate main body, wherein the gripper comprises a pair of opposed grip surfaces and, wherein the pair of opposed grip surfaces are connected by a first connecting surface which extends from a distal end of the funnel, and a second connecting surface which is connected to a free end of the first connecting surface and which has a curved shape.
The width of the first connecting surface and the second connecting surface may be between 4 mm and 10 mm. The width of the first connecting surface and the second connecting surface may be between 5 mm and 9 mm. The width of the first connecting surface and the second connecting surface may be between 6 mm and 8 mm. The width of the first connecting surface and the second connecting surface may be between 6.5 mm and 7.5 mm. Providing the pair of opposed grip surfaces spaced apart by the width of the first connecting surface and the second connecting surface is particularly advantageous as it enables users to gain a better grip of the surfaces by providing a more substantial portion to hold. This is particularly useful for users having reduced manual dexterity as it enables them to hold the gripper more easily, thereby enabling them to manoeuvre the catheter assembly with greater control during insertion and use. The pair of opposed grip surfaces may be generally triangular in shape. The pair of opposed grip surfaces may be shaped such that the free end of the first connecting surface is provided furthest from the longitudinal axis. The pair of opposed grip surfaces may taper towards the longitudinal axis from the distal end of the funnel towards the proximal end of the funnel. In this way, the gripper is shaped to encourage the user to hold it at a point towards the free end of the first connecting surface which is positioned furthest away from the drainage outlet and, therefore, furthest away from the flow of urine exiting the catheter assembly.
The pair of opposed grip surfaces may be concave. Additionally or alternatively, each of the opposed grip surfaces may be provided with a concave portion. The concave portion may correspond to the part of the pair of opposed grip surfaces where a user is likely to grasp. The concave portion may be defined by a ridge. The ridge may extend fully around the periphery of at least one of the pair of opposed grip surfaces. Alternatively, the ridge may extend partially around the periphery of at least one of the pair of opposed grip surfaces. Providing a concave surface and/or portion enables users to securely hold the gripper which is particularly beneficial in assisting users with reduced manual dexterity to grasp and guide the catheter assembly. Furthermore, providing a concave portion advantageously guides the user to position their fingers on the concave portions such that they may be encouraged to grasp the gripper at a point distal to the flow of urine out of the drainage outlet.
One or both of the pair of opposed grip surfaces may comprise one or more surface features. For example each grip surface may comprise at least one surface feature; one of the pair of opposed grip surfaces may comprise a plurality of surface features; or each of the opposed grip surfaces may comprise a plurality of surface features. The or each surface features may comprise a protrusion. The or each surface feature may comprise a groove. Where a plurality of surface features are provided, at least one surface feature may comprise a protrusion and at least one surface feature may comprise a groove. The plurality of protrusions and/or grooves may comprise parallel lines. Additionally or alternatively, at least one protrusion may comprise a curved line. Where a plurality of surface features are provided, they may comprise a plurality of curved lines. The plurality of curved lines may be concentric. Additionally or alternatively, the plurality of protrusions and/or grooves may comprise at least one of a regular and an irregular pattern of circles or other shapes. By way of non-limiting example, other shapes may include squares, triangles, hexagons, crosses. Providing such surface features assists users having impaired manual dexterity as it enables them to gain a more secure hold of the pair of opposed grip surfaces by increasing the coefficient of friction of the surfaces.
The at least one surface feature may protrude from a recessed portion of the grip surface. The at least one surface feature may protrude from the recessed portion of the grip surface by at least 0.5 mm, 0.75 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.25 mm, or 2.5 mm. The at least one surface feature may protrude from the recessed portion of the grip surface by a maximum distance of no more than 4 mm, 3.5 mm, 3 mm 2.5 mm, 2 mm, 1.5 mm, 1.25 mm, 1 mm, or 0.75 mm. The at least one surface feature may protrude from the recessed portion of the grip surface by a distance in the range of 0.5 mm- 4.0 mm. In a preferred embodiment, the at least one surface feature may protrude from the recessed portion of the grip surface by a distance of 0.75 mm.
The external flushing portion may be configured, in use, to provide fluid communication between the catheter and the urethra via the at least one flushing channel. The external flushing portion may extend from an insertion portion to the outlet end. The external flushing portion may define a fluid flow path from the insertion portion to the outlet end which is open to the exterior of the elongate main body. The at least one flushing channel may be formed on an external surface of the elongate main body. The external flushing portion may have a solid central core. The external flushing portion may have a uniform cross-sectional area in the transverse direction along the length thereof. The part of the external flushing portion comprising the at least one flushing channel may have a solid cross-section. The part of the external flushing portion comprising the at least one flushing channel may be entirely solid. Providing at least one flushing channel on an external surface of the catheter allows a flow of urine to contact the urethra during use. The flow of urine may act to flush the urethra and help reduce the possibility of infection.
The funnel may comprise at least one drainage outlet. The at least one drainage outlet may not extend beyond the distal end of the gripper. The at least one drainage outlet may be in fluid communication with the at least one flushing channel. The at least one drainage outlet may be aligned with the at least one flushing channel. In a preferred embodiment, there may be provided two flushing channels offset by 180° about the circumference of the elongate main body, in fluid communication with the drainage outlet.
A junction may be defined between the proximal end of the funnel and the outlet portion. The outlet portion may be shaped at the junction to guide liquid from the at least one flushing channel toward the at least one drainage outlet. The outlet portion may be angled at the junction to guide liquid from the at least one flushing channel toward the at least one drainage outlet. The outlet portion may be shaped at the junction to collect liquid flowing along the at least one flushing channel.
The number of flushing channels may be any suitable number. The number of flushing channels may be between one and four. In a preferred embodiment, the external flushing portion may comprise two (and optionally only two) flushing channels. The two flushing channels may be arranged directly opposite each other. The gripper may be provided at 90° to the plane between two flushing channels; in particular the gripper may be provided at 90° to the plane between two flushing channels at the junction with the funnel. The flushing channels may be arranged at evenly spaced intervals about the circumference of the elongate main body.
The or each flushing channel may comprise a straight portion. The or each flushing channel may comprise a helical portion. The or each flushing channel may terminate at the outlet end of the elongate main body.
The catheter assembly may be formed from separate component pieces that are attached together. In particular, the main body and the funnel may be separate component pieces. The separate component pieces (e.g. the main body and the funnel) may be attached via a press fit connection. Providing separate component pieces is particularly advantageous as it enables each component to be manufactured individually thereby enabling the manufacturing processes to be tailored to the properties of each component. The elongate main body may be formed by injection moulding. Additionally or alternatively, the elongate main body may be extruded. The funnel may be formed by injection moulding.
An outer surface of a main body of the funnel may have a substantially frustoconical shape. The outer diameter of the outer surface of the main body of the funnel may increase from the proximal end to the distal end. Alternatively, the outer surface of the main body of the funnel may have a substantially cylindrical shape or a substantially elliptical shape. The outer diameter of the outer surface of the main body may be constant along the entire length of the funnel. Alternatively, the outer diameter of the outer surface of the main body may vary along the entire length of the funnel.
An inner surface of a main body of the funnel may have a substantially frustoconical shape. The outer diameter of the inner surface of the main body of the funnel may increase from the proximal end to the distal end. Alternatively, the inner surface of the main body of the funnel may have a substantially cylindrical shape or a substantially elliptical shape. The outer diameter of the inner surface of the main body may be constant along the entire length of the funnel. Alternatively, the outer diameter of the inner surface of the main body may vary along the entire length of the funnel.
The funnel may be configured to receive the outlet portion of the elongate main body. The funnel and outlet portion may be configured to fit together via a press fit connection. The funnel and outlet portion may be configured to fit together via an interlocking mechanism. The funnel and outlet portion may be configured to fit together via a “click mechanism”. The funnel and outlet portion may be configured to fit together via a “snap mechanism”. The funnel and outlet portion may be configured to fit together in a non-releasable manner. The proximal end of the funnel may be configured to receive the outlet portion. The outlet portion may comprise a snap ring. Additionally or alternatively, the outlet portion may comprise at least one snap clip. In a preferred embodiment, the outlet portion may comprise two snap clips (and optionally only two) diametrically opposing each other. The two snap clips may be configured to be positioned 90° to the plane between two flushing channels. The snap ring and/or the at least one snap clip may be provided about the circumference of the outlet portion. The snap ring and/or the at least one snap clip may protrude radially outwards. The snap ring and/or the at least one snap clip may extend partially or fully about the circumference of the outlet portion. The snap ring and/or the at least one snap clip may define a trapezoidal profile.
The internal surface of the funnel may comprise a ring. The ring may extend around the circumference of the internal surface of the funnel. The ring may extend radially inwards. The ring may extend partially or fully about the circumference. The ring may have a profile which corresponds to that of the snap ring and/or the at least one snap clip. The ring may have a substantially trapezoidal profile. The snap ring and/or the at least one snap clip may be shaped to closely receive the ring in an interlocking mechanism. The interlocking mechanism may comprise the mating of the ring and snap ring and/or the at least one snap clip to hold the funnel in position.
The snap ring and/or the at least one snap clip and the ring may be provided on the outlet portion and internal surface of the funnel respectively, such that they align when the funnel is attached to the outlet portion. In this way, it is easy to detect when the funnel has been attached in the correct position as it will “snap” into place thereby ensuring that the funnel is in the correct position to allow the catheter assembly to function correctly whilst minimising leakage.
Additionally or alternatively, the outlet portion may comprise at least one guide formation. The at least one guide formation may extend from an external surface of the elongate main body. The at least one guide formation may extend radially outwards. The proximal end of the funnel may be configured to abut the at least one guide formation. This is particularly advantageous as the provision of the funnel abutting the at least one guide formation indicates that the funnel has been attached in the correct position and that the connection is stabilised. The proximal end of the funnel may be shaped to direct fluid flow toward the at least one drainage outlet. The proximal end of the funnel may be shaped to collect fluid leaving the at least one flushing channel and entering the at least one drainage outlet. For example, the proximal end of the funnel may comprise a lip or a converging portion. By shaping the funnel to direct and collect fluid, the risk of urine exiting the urethra leaking is minimised.
The insertion portion facilitates insertion of the catheter into and along the urethra. The insertion portion may be solid. The insertion portion may comprise a rounded tip and a solid wall at the proximal end. The insertion portion may comprise the proximal end of the at least one flushing channel.
The external flushing portion may comprise one or more walls each having an external surface arranged, in use, to contact the urethra wall and support the urethra in an open state. The, or each, wall may define the, or each, flushing channel. The, or each, wall may extend longitudinally. The, or each, wall may be straight or helical. The pitch of a helical wall may be constant. The, or each, wall may comprise a longitudinal axis. The cross-section of the, or each, wall transverse to the longitudinal axis of the main body may comprise a rounded profile. The rounded profile may comprise one or more radiuses of curvature.
The, or each, flushing channel may provide a fluid flow path to the outlet portion. The, or each, flushing channel may extend fully to the outlet portion. The, or each, flushing channel may extend continuously along the main body from the insertion portion to the outlet end.
The elongate main body may be straight (i.e., in the absence of bending forces, at rest, the main body may be substantially straight). The main body may be rigid (i.e., substantially rigid, for example a shore hardness of A80) thereby aiding insertion and maintaining the shape of the at least one flushing channel in use.
The, or each, wall may extend radially from a central axis of the main body. The, or each, radially extending wall may comprise an outermost surface and respective opposing side walls. The radially outermost surface of the, or each, wall may define an outside diameter of the external flushing portion. The outside diameter may be constant along the external flushing portion and insertion portion of the catheter. Hence, the overall width of the external flushing portion and insertion portion of the catheter may be constant along the length thereof. The cross-sectional area of the, or each, flushing channel may be constant along the length of the external flushing portion. The combined area of the outer surface of the walls may be greater than the combined area of the open faces of the flushing channels. Alternatively, the combined area of the open faces of the flushing channels may be greater than the combined area of the outer surface of the walls. Preferably, the outer flow surface area created by the flushing channels is equal to or greater than the surface area of the inner lumen of the equivalent conventional catheter (i.e., a catheter comprising a tube defining an inner lumen along the length thereof for the outflow of urine) of the corresponding CH size.
The catheter assembly may be a male urinary catheter assembly or a female urinary catheter assembly. In a preferred embodiment, the catheter assembly is an intermittent female urinary catheter assembly.
For a female catheter. The length of the catheter may be between 80 mm andl40 mm, preferably 100 mm. The length of the external flushing portion may be between 60 mm and 120 mm, preferably 90 mm.
For a male catheter, the length of the catheter may be between 360 mm and 425 mm, preferably 405 mm. The length of the external flushing portion may be between 300 mm and 350 mm, preferably 325 mm.
The diameter of the insertion portion and the external flushing portion may be between 2mm and 6 mm depending on the size requirements of the intended user.
The depth of the at least one flushing channel may be between 0.5 mm and 2 mm, preferably 1mm.
The present disclosure provides in a second aspect, a method of manufacturing an intermittent urinary catheter assembly comprising the steps of providing an elongate main body having at least one flushing channel in a surface thereof and a funnel comprising a gripper; and attaching the funnel to an outlet end of the elongate main body such that the gripper extends away from a longitudinal axis of the main body.
The method may comprise forming the at least one flushing channel in a surface of the elongate main body. The method may comprise providing the funnel with a gripper. The method may further comprise the steps of separately forming the funnel with its gripper and the elongate main body, including its at least one flushing channel, via injection moulding before attaching them together. Additionally or alternatively, the method may further comprise the steps of separately forming the funnel with its gripper and the elongate main body, including its at least one flushing channel, via at least one of injection moulding and extrusion.
The method of manufacturing an intermittent urinary catheter assembly may further comprise the steps of providing the funnel with an interlocking mechanism which engages the outlet end of the elongate main body.
The method of manufacturing an intermittent urinary catheter assembly may further comprise the steps of attaching the funnel to an outlet end of the elongate main body via the interlocking mechanism. Providing an interlocking mechanism is particularly advantageous as it prevents removal of the funnel once attached to the outlet end of the elongate main body.
Additionally or alternatively, the method of manufacturing an intermittent urinary catheter assembly may further comprise the steps of attaching the funnel to an outlet end of the elongate main body via a press fit connection. The method may further comprise the steps of bonding and/or curing the connection.
Additionally or alternatively, the method of manufacturing an intermittent urinary catheter assembly may further comprise the steps of providing at least one of a snap ring and at least one snap clip extending partially or fully about the circumference of the outlet portion protruding radially outwards; and a ring extending around the circumference of the internal surface of the funnel and extending radially inwards having a profile which corresponds to that of the snap ring and/or the at least one snap clip; pressing the funnel onto the outlet portion of the elongate main body until the groove closely receives and interlocks with either the snap ring and/or the at least one snap clip.
Additionally or alternatively, the method of manufacturing an intermittent urinary catheter assembly may further comprise the steps of providing at least one guide formation extending from an external surface of the elongate main body; and pressing the funnel onto the outlet portion of the elongate main body until the proximal end of the funnel abuts the at least one guide formation.
Of course, the method of the second aspect of the disclosure may be a method of forming the intermittent urinary catheter of the broad aspect or the first aspect of the disclosure, optionally including any of the optional features described above.
The present disclosure provides, in a third aspect, a method of catheterization using a catheter according to any aspect described herein. The method may comprise the steps of: (i) providing an intermittent urinary catheter assembly comprising an elongate main body and a funnel, the elongate main body having an insertion end for insertion into a urethra and bladder, an outlet end for the outflow of fluid from the catheter, and an external flushing portion extending between the insertion end and the outlet end, wherein the external flushing portion comprises at least one flushing channel, wherein the funnel is attached to the outlet end of the elongate main body, and further comprises a gripper extending away from a longitudinal axis of the elongate main body, and (ii) using the gripper to insert the catheter assembly into the urethra into the bladder via the urethra until the flushing channel is in fluid communication with the bladder so that urine can drain from the bladder through the urethra along the at least one flushing channel of the catheter assembly. The outlet portion may be arranged at the base of the urethra to collect urine flowing along the at least one flushing channel and direct the urine into the at least one drainage outlet. The method may comprise grasping the catheter via the gripper to assist with insertion of the catheter assembly and directing the outflow of fluid.
The skilled person will appreciate that except where mutually exclusive, a feature described in relation to any one of the aspects, embodiments, or examples described herein may be applied to any other aspect, embodiment, or example. Furthermore, except where mutually exclusive, any feature described herein may be applied to any aspect and/or combined with any other feature described herein.
Detailed Description of the Invention
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:
Figure 1 shows a side view of a catheter assembly according to the present disclosure;
Figures 2a show a side view of the catheter assembly of figure 1 ;
Figure 2b shows a cross sectional view along the longitudinal axis of section F-F of the elongate main body of the catheter assembly of figure 2a;
Figure 3a shows an end view of the funnel attached to the elongate main body of the catheter of figures l-2b;
Figure 3b shows an enlarged view of the section of figure 3 a denoted by the dashed line;
Figure 4 shows a cross sectional side view of catheter assembly of figures l-3b;
Figure 5a shows a side view of a second embodiment of the catheter assembly according to the present invention;
Figure 5b shows a cross-sectional view of section F-F of the elongate main body of the catheter assembly of figure 5 a;
Figure 6a shows an end view of the funnel attached to the elongate main body of the catheter of figures 5a-5b;
Figure 6b shows an enlarged view of the section of figure 6a denoted by the dashed line; and
Figure 7 shows an axonometric projection from the distal end of the catheter assembly of figures 5a-6b. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of various embodiments and the inventive concept. However, those skilled in the art will understand that the present invention may be practised without these specific details or with known equivalents of these specific details, that the present invention is not limited to the described embodiments, and that the present invention may be practiced in a variety of alternative embodiments. It will also be appreciated that well known methods, procedures, components, and systems may have not been described in detail.
In the following description, reference to longitudinal should be taken to be in relation to the longitudinal axis of the catheter; the longitudinal axis being the axis extending between the insertion end and the outlet end. References to distal and proximal made herein should be taken to be in relation to the insertion end of the catheter.
The catheters described herein are female intermittent urinary catheters. However, it will be appreciated that the inventive concepts and features described herein may be applied equally to male intermittent urinary catheters.
Referring to figures 1-4, a first embodiment of an intermittent urinary catheter assembly 1 comprises an elongate main body 2 and a funnel 3. The elongate main body has an insertion end 4 for insertion of the catheter assembly 1 into a urethra and bladder, and an outlet end 5 (best seen in figure 3b) for the outflow of fluid e.g., urine from the catheter assembly 1, via the funnel 3. An insertion portion 6 for facilitating insertion of the catheter assembly 1 into and along the urethra is formed at the insertion end 4, and an outlet portion 7 for connection to the funnel to allow the outflow of fluid e.g., urine from the elongate main body 2 is formed at the outlet end 5. The funnel 3 is attached to the outlet end 5 of the elongate main body 2 and comprises a gripper 8 which extends perpendicularly away from a longitudinal axis 9 of the elongate main body 2.
The elongate main body 2 further comprises an external flushing portion 10 extending between the insertion end 4 and the outlet end 5, from the insertion portion 6 to the outlet end 5. The external flushing portion 10 comprises at least one flushing channel 11 and is configured to provide fluid communication between the catheter and the urethra, by defining a fluid flow path from the insertion portion 6 to the outlet end 5 via the at least one flushing channel 11. The at least one flushing channel 11 is formed in an external surface of the elongate main body 2 and is open faced in the radial direction so that, when inserted, the catheter 1 mates with the urethral wall (not shown) to enclose the at least one flushing channel 11. Hence, when inserted, the urethral wall is exposed to a flow of urine flowing along the flushing channel 11 of the external flushing portion 10, thereby flushing the urethra and helping to reduce the possibility of infection. In this particular embodiment, there are provided two straight flushing channels 11 offset by 180° about the circumference of the elongate main body 2, which extend continuously to the outlet end 5 where they terminate.
With reference now to figure 2b the external flushing portion 10 comprises one or more walls 12 which each define the or each flushing channel 11. The external surface of the one or more walls 12 is arranged in use to contact the urethra wall and support the urethra in an open state. In this example, there are two walls 12 which are straight, extending longitudinally along the longitudinal axis 9, and defining two flushing channels 11. However, it will be understood that in alternative embodiments there may be a different number of flushing channels 11 and walls 12, and the walls 12 may also, for example, be helical.
The external flushing portion 10 has a solid central core 13 having a uniform solid cross section which can clearly be seen in the cross-sectional view of figure 2b. The solid central core 13 extends along the central axis of the elongate main body 2. The two walls 12 extend radially from a central axis of the elongate main body 2 and each comprises an outermost surface 14 and opposing sidewalls 15. The outermost surface 14 of the walls is convex and curves about the circumference of the elongate main body 2. The outer diameter of the external flushing portion 10 is defined by the distance between the outermost surfaces 14 of the two diametrically opposed walls 12.
The radius of curvature of the outermost surface of a wall 14 is substantially the same as that of the external walls of the insertion portion 4, such that the insertion portion 4 and external flushing portion 10 share substantially the same outermost diameter. Accordingly, the outermost diameter is approximately constant along the length of the elongate main body 2 intended for insertion into the urethra. The flushing channels 11 are substantially the same in shape and dimension and are positioned directly opposite one another in the external surface of the elongate main body 2. Accordingly, the external flushing portion 10 is symmetrical about a plane extending along the longitudinal axis 9 and each wall 12 has a diametrically opposed counterpart.
In the present example, the flushing channels 11 are defined by a base 16 being part of the solid central core 13, and the sidewalls 15 of the two adjacent walls 12. The adjacent walls 12 are angled to form a flushing channel with a substantially “V” or “U” shaped cross section which is constant along the length of the flushing channels 11. The cross section may also be referred to as wedge-shaped or being a tapered-cross section. However, it will be understood that other flushing channel shapes may be adopted, such as, for example, square, concave, or rectangular shaped cross sections.
In the present embodiment, shown most clearly in figure 1, the insertion portion 6 comprises a rounded tip 17 and a solid outer wall 18 at the at the end proximal to the insertion end 4. The insertion portion also comprises the proximal end of the flushing channel 19 at the distal end, which defines the start of the flushing channel 11 such that urine may enter the flushing channels 11 within the bladder and flow through the urethra via the same flushing channels 11. The proximal end of the flushing channel 19 comprises an angled portion which encourages urine from the bladder to flow from the proximal end of the flushing channel 19 along the major portion of the flushing channel 11. It will be understood that in this embodiment, the insertion portion 6 comprises the rounded tip 17 at the insertion end 4 to aid insertion into the urethra and bladder. However, this is non limiting and in other embodiments the insertion end 4 may be provided with other formations such as a bulb or cone shaped member or a non-circular cross section which may all aid insertion of the catheter assembly 1.
With reference to figures 1-4, the outlet portion 7 of the elongate main body 2 comprises the at least one flushing channel 11 which terminates at the outlet end 5 without changing cross section. The outlet portion 7 of the main body 2 is inserted into the funnel 3 and connected thereto as described below. The funnel 3 comprises at least one drainage outlet 23. The outlet portion 7 is shaped to guide liquid from the at least one flushing channel 11 through the at least one drainage outlet 23. In this particular embodiment, there is a single drainage outlet 23 which does not extend beyond the distal end of the gripper 8, in fluid communication with the flushing channels 11 providing a flow path through the funnel 3 such that urine from the bladder may pass through the catheter assembly 1 and out of the distal end of the funnel 3 into a suitable receptacle such as a toilet bowl. In this particular embodiment, the drainage outlet 23 is defined by the inner surface of the funnel 26. The outer diameter of the drainage outlet 23 increases from the proximal end to the distal end. The outlet portion 7 is shaped at a junction 25 between the proximal end of the funnel 3 and the outlet portion 7 to collect liquid flowing down the flushing channels 11 and guide the liquid from the flushing channels 11 toward the corresponding drainage outlet 23.
The catheter assembly 1 is formed from separate component pieces, the elongate main body 2 and the funnel 3, which are attached together via a press fit connection. This is particularly advantageous as it enables both the funnel 3 and the elongate main body 2 to be formed via separate manufacturing methods to achieve the optimal component finish. In this particular embodiment, both components were formed by injection moulding. However, it will be understood that in other embodiments it is possible to use alternative manufacturing methods such as extrusion processes.
The outer diameter of the main body of the funnel 34 increases from the proximal end to the distal end, resulting in a substantially frustoconical shape. The proximal end of the funnel 3 is configured to receive the outlet portion 7 of the elongate main body 3 and they are attached via a non-releasable interlocking mechanism.
As best seen in figures 3b and 4, the outlet portion 7 comprises two snap clips 29 protruding radially outwards. The two snap clips 29 are positioned to diametrically oppose one another and are positioned 90° to the plane between two flushing channels 11. The internal surface of the funnel 3 comprises a ring 30 extending around the circumference, which is shaped to be closely received by the two snap clips 29 of the outlet portion 7 in the interlocking mechanism. The ring in this particular embodiment has a substantially trapezoidal profile with a ramp surface facing the proximal end of the funnel 3, to guide the snap clips inwardly as the main body 2 is pushed towards the distal end of the funnel. The trapezoidal profile matches the profile of a groove in each of the two snap clips 29, behind their feet 27, such that when the funnel 3 receives the outlet portion 7 of the elongate main body 2, the ring 30 and snap clips 29 mate, with the trapezoidal ring holding the funnel 3 in position because the feet 27 snap into place behind and cannot be pulled back over the ring 30.
The elongate main body 2 also comprises two diametrically opposing guide formations 31 extending radially outwards from an external surface. In this particular embodiment, the two guide formations 31 have the form of a pair of legs which protrude radially outwards, although it will be understood that other profiles are acceptable. The guide formations 31 extend from the convex outermost surfaces 14 of the two walls 13 and are arranged perpendicularly to the flushing channels 11 (so as not to present an obstacle to flow).
The proximal end of the funnel 32 is configured to abut the two guide formations 31 when it is attached to the elongate main body 2 such that the funnel 3 is positioned correctly, enabling the ring 30 and the snap clips 29 to mate and hold the funnel 3 in position.
The proximal end of the funnel 3 is angled to direct urine to flow into the drainage outlet. In this particular embodiment, the funnel 3 is aligned such that the gripper 8 extends at 90° from both flushing channels 11. It will be understood that the gripper may be positioned at different angles. For example, it could be offset from the longitudinal axis, extending tangentially from the funnel 3.
With reference to figures l-3b the gripper 8 has a generally wing-shaped form, with a pair of opposed grip surfaces 20 extending perpendicularly away from the longitudinal axis of the elongate main body 9 such that a user may hold the gripper at a distance sufficiently removed from the flow of urine through the catheter assembly 1 so as not to risk contacting the urine in use. The pair of opposed grip surfaces 20 are connected via a first connecting surface 21 extending from a distal end of the funnel 3, and a second connecting surface 22 connected to the free end of the first connecting surface 21. The second connecting surface extends from the free end of the first connecting surface 21 to a proximal end of the funnel. The second connecting surface 22 having a curved shape and constant width such that the pair of opposed grip surfaces 20 are in parallel alignment with one another. In this particular embodiment the junction between the first connecting surface 21 and the second connecting surface 22 is curved to remove pointed connecting surfaces which may harm users. However, it will be understood that this feature is optional, and the radius of curvature may be greater or lesser than illustrated in this embodiment.
The wing-shaped gripper 8 and hence the pair of opposed grip surfaces 20 extend the entire length of the funnel from the proximal end to the distal end of the funnel 3; they are generally triangular, with one side connected to the funnel; an apex at the proximal end of the funnel; the side opposing the apex extending orthogonal to the longitudinal axis, and a convex-curved hypotenuse. The winged shape of the pair of opposed grip surfaces 20, which has its tip furthest from the funnel at the distal end of the funnel encourages a user to grip the gripper 8 with their thumb and forefinger. The pair of opposed grip surfaces are also provided with a peripheral ridge 42 about the edge of each surface. The ridge 42 defines an outer edge of a concave recessed portion 43 of the grip surface 20 which assists the user in handling the gripper 8 by providing a specific area for the thumb and forefinger.
The pair of opposed grip surfaces extend perpendicularly away from the longitudinal axis by a maximum distance of approximately 22 mm. However, it will be understood that in alternative embodiments, the pair of opposed grip surfaces may extend perpendicularly away from the longitudinal axis by different maximum distances, for example, in the range of 55 mm- 50 mm, 17.5 mm-40 mm, or 20 mm- 35 mm. The thickness of the gripper between the opposed grip surfaces in the recessed region is in the region of 3-5mm, and each ridge has a depth of about 0.75 mm, such that the total depth of the gripper is approximately 4.5-6.5mm, but again in alternative embodiments the thickness could be bigger or smaller. The length of the winged gripper is at least 15mm, preferably at least 25mm, and most preferably at least 30 mm and in this embodiment extends the entire length of the funnel, which is approximately 30 mm. The pair of opposed grip surfaces 20 are thus ideally sized to accommodate grasping of the gripper by a thumb and forefinger.
With reference to figures 5a-7, a second embodiment of the present invention is shown. The catheter assembly 1 of the second embodiment includes many of the same features as the first embodiment, like features are given like reference numerals, and the detailed description focusses on the differences in the second embodiment.
The differences primarily lie in the connection between the main body 2 and the funnel 3, and in aspects of the gripper 8 of the second embodiment. For example, whilst the gripper 8 of the second embodiment is generally the same size and shape as that of the first embodiment, it additionally includes a plurality of surface features 33. The plurality of surface features 33 in this embodiment are a series of three equally spaced curved lines protruding from the pair of opposed grip surfaces 20 to the same extent as the peripheral ridge around the edge of the grip surfaces 20. Each curved line protrudes approximately 0.75 mm from the recessed portion 43, enabling the skin of the users fingers to mould into the gaps to provide a secure grip. However, it will be understood that each surface feature 33 may protrude to a greater or lesser extent. For example, in the range of 0.5 mm- 4 mm, and the greater the protrusion, the greater surface area of skin will be in contact with the pair of opposed grip surfaces 20 such that a person may hold the gripper more securely.
In this embodiment, each curved line follows the contours of the second connecting surface 22 and extends across the majority of each grip surface 20 such that the surface may provide sufficient grip for a user irrespective of where they choose to hold it and/or how they choose to manipulate and/or rotate it during insertion and use of the catheter assembly 1. Each curved line extends at approximately 30 degrees to the longitudinal axis 9, such that any slipping of the digits along the lines is more likely to be in longitudinal than orthogonal, meaning the angle at which the catheter is being held is less likely to change than the axial position.
The surface features of this particular embodiment are one example however, it will be understood that a variety of other surface features 33 may also be used which are equally effective. The plurality of surface features 33 effectively increase the coefficient of friction of the pair of opposed grip surfaces 20. This is particularly beneficial for users with reduced manual dexterity as it allows them to gain a better hold of the gripper which may then be used to manoeuvre and insert the catheter assembly 1 whilst remaining distanced from the flow of urine through the assembly 1. In this particular embodiment, the elongate main body 2 is substantially the same as that of the first embodiment and the external flushing portion 10 also comprises two flushing channels 11 diametrically opposed which extend along the entire length of the external flushing portion 10, terminating at the outlet end 5. However, unlike the first embodiment, the outlet portion 7 of the second embodiment does not include special features, such as the guide formations 31 or clips to attach it to the funnel. Rather, the walls 13 and outlet channels 11 maintain their profile all the way to the outlet end 5 of the main body. The funnel 3 comprises two distinct drainage outlets 23 which align with the flushing channels 11. Each flushing channel 11 is in fluid communication with a drainage outlet 23. In this way, two main fluid flow paths are provided from the bladder, through the urethra via the flushing channels 11, and out of the funnel 3 for disposal into a suitable receptacle.
The funnel 3 of the second embodiment is attached to the elongate main body 2 using a press fit connection. The funnel 3 closely receives the elongate main body 2 and has an attachment portion 37 corresponding to the shape of the convex outermost surface 14 of the two walls of the elongate main body 2. The attachment portion 37 has a natural diameter slightly smaller than that of the outermost surface of the two walls of the elongate main body 2, but is made of a resilient material that can be elastically stretched to allow the elongate main body to be introduced through one end such that the funnel 3 may resile towards its natural position and thus closely receive the outlet portion 7 in a sealed manner such that no liquid may leak through.
Each drainage outlet 23 is formed by a curved surface 38 positioned between the attachment portion 37 and defining two distinct passageways 40 for the drainage of fluid from the catheter assembly 1. The curved surface 38 encloses the flushing channel 11 at the outlet portion 7 directing fluid exiting the urethra toward the distal end of the funnel 3. The distinct passageways 40 have a somewhat elliptical shape to assist in controlling the flow direction. However, it will be understood that each drainage outlet may be formed by an alternatively shaped surface such as triangular and the same effect will be achieved.
The base portion 41 of the funnel 3 comprises a flat surface having a shape corresponding to that of the solid central core 13. When the outlet portion 7 is received by the funnel 3, the solid central core 13 is aligned with the base portion 41 of the funnel 3 ensuring that the flushing channels 11 lead directly into their respective drainage outlets 23 thereby minimising leakage of urine from the catheter assembly 1.
In some embodiments, the catheter is formed of a material of the group comprising: polyvinyl chloride, polytetrafluoroethylene, polyolefins, latex, silicones, synthetic rubbers, polyurethanes, polyesters, polyacrylates, polyamides, thermoplastic elastomeric materials, styrene block copolymers, poly ether block amide, thermoplastic vulcanizates, thermoplastic copolyesters, thermoplastic polyamides, and water disintegrable or enzymatically hydrolysable material, or combinations, blends or co-polymers of any of the above materials.
In preferred embodiments, the catheter is formed of a material of the group comprising: polyolefins, polyesters, polyacrylates, polyamides, thermoplastic elastomeric material, poly ether block amide, thermoplastic vulcanizates, thermoplastic copolyesters, thermoplastic polyamides, fluororubber, and water disintegrable or enzymatically hydrolysable material or combinations, blends or copolymers of any of the above materials.
In some embodiments, said water disintegrable or enzymatically hydrolysable material comprises a material of teh group comprising: polyvinyl alcohol, extrudable polyvinyl alcohol, polyacrylic acids, polylactic acid, polyesters, polyglycolide, polyglycolic acid, poly lactic-co-glycolic acid, polylactide, amines, polyacrylamides, poly(N-(2-Hydroxypropyl) methacrylamide), starch, modified starches or derivatives, amylopectin, pectin, xanthan, scleroglucan, dextrin, chitosans, chitins, agar, alginate, carrageenans, laminarin, saccharides, polysaccharides, sucrose, polyethylene oxide, polypropylene oxide, acrylics, polyacrylic acid blends, poly(methacrylic acid), polystyrene sulfonate, polyethylene sulfonate, lignin sulfonate, polymethacrylamides, copolymers of aminoalkyl-acrylamides and methacrylamides, melamineformaldehyde copolymers, vinyl alcohol copolymers, cellulose ethers, poly-ethers, polyethylene oxide, blends of polyethylene- polypropylene glycol, carboxymethyl cellulose, guar gum, locust bean gum, hydroxypropyl cellulose, vinylpyrrolidone polymers and copolymers, polyvinyl pyrrolidone-ethylene- vinyl acetate, polyvinyl pyrrolidone-carboxymethyl cellulose, carboxymethyl cellulose shellac, copolymers of vinylpyrrolidone with vinyl acetate, hydroxyethyl cellulose, gelatin, poly- caprolactone, poly(p-dioxanone), or combinations, blends or co-polymers of any of the above materials. In some preferred embodiments, the catheter is formed of a polyolefin material, especially polyethylene and/or polypropylene. In some preferred embodiments, the catheter is formed of a thermoplastic elastomeric material. In some preferred embodiments the catheter may be made from a polyolefin based synthetic thermoplastic polyolefin elastomer (TPE) containing a hydrophilic additive. In some preferred embodiments the catheter may be made from a polymer mixture comprising a first polymer and a second polymer, wherein the first polymer is a thermoplastic or thermo-curing polymer, and the second polymer is an amphiphilic block copolymer possessing both hydrophilic and lipophilic properties. A possible suitable polymer mixture is described and disclosed in EP2493521A1.
In some embodiments the funnel is formed from a thermoplastic. For example, the funnel may be formed from low density polyethylene or a thermoplastic elastomer. 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.