Technical Field of the Invention

The present invention provides a urinary catheter which is configured to aid flushing of the urethra in use.

Background to the Invention

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 patkients 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. This is because intermittent catheters typically comprise a closed lumen which expels urine from the bladder without it contacting the urethral wall. As such there can be a persistent build-up of bacteria and debris (e.g., skins 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.

CN210992518U describes an indwelling catheter capable of flushing a urethra. The catheter includes a plurality of grooves formed along the length direction, and a plurality of small holes are formed at the bottom of each groove at intervals. During use, secretions in the urethra of a patkient enter the grooves and are discharged.

CN206239873 describes an indwelling male catheter having a wire mesh support structure which allows urine to contact the urethra.

US 10668249 describes an intermittent catheter having a distal portion, a proximal portion, and a plurality of drainage eyes disposed at a junction between the distal portion and the proximal portion. The distal portion includes a tip, a plurality of elongated ribs, and a plurality of external flow paths. The proximal portion includes an internal lumen and a proximal end. The plurality of drainage eyes communicate with the plurality of external flow paths and the internal lumen.

The present invention seeks to provide an improved catheter for flushing the urethra in use.

Summary of the Invention

The present invention provides a catheter according to the appended claims.

The present disclosure provides, in a first aspect, a catheter comprising: an elongate main body having an insertion end for insertion into a urethra and bladder, and an outlet end comprising an outlet portion for the outflow of fluid from the catheter. The elongate main body may further comprise an external flushing portion extending from the outlet portion to the insertion end. The external flushing portion may comprise a plurality of external flow channels formed in an external surface of the main body.

Providing external flow channels 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 external flow channels may be arranged to provide the only flow paths for the flow of urine along at least a portion of the urethra when the catheter is inserted into the urethra.

The outlet portion may comprise one or more drainage channels and a plurality of drainage apertures formed at a junction between the outlet portion and the external flushing portion. The external flow channels, drainage apertures, and drainage channels may be arranged such that the external flow channels are in fluid communication with the one or more drainage channels via the drainage apertures. One or more, or each, of the plurality of external flow channels may extend along the entire length of the external flushing portion to the insertion end.

Providing external flow channels that extend along the entire length of the external flushing portion to the insertion end may create a flow channel from the bladder as soon as the catheter is inserted into the bladder, thereby making the catheter less sensitive to axial position in use (i.e., less sensitive to how far in the axial direction the catheter is inserted).

Accordingly, one embodiment of the invention provides a catheter comprising: an elongate main body having an insertion end for insertion into a urethra and bladder, and an outlet end comprising an outlet portion for the outflow of fluid from the catheter, the elongate main body further comprising an external flushing portion extending from the outlet portion to the insertion end, the external flushing portion comprising a plurality of external flow channels formed in an external surface of the main body, wherein the outlet portion comprises one or more drainage channels and a plurality of drainage apertures formed at a junction between the outlet portion and the external flushing portion and arranged such that the external flow channels are in fluid communication with the one or more drainage channels via the plurality of drainage apertures, wherein one or more of the plurality of external flow channels extend along the entire length of the external flushing portion to the insertion end.

The external flow channels may be open at the insertion end with no end wall. The external flow channels may each curve toward a common rounded tip at the insertion end. The insertion end may extend all the way to the tip.

The drainage apertures may extend axially and/or radially. The drainage apertures may meet at a common space at a central axis of the catheter. Each external flow channel may comprise straight portions.

The external flushing portion may have a solid central core. The external flushing portion may have a uniform cross section in the longitudinal direction. The part of the external flushing portion comprising the external flow channels may have a solid cross-section. The part of the external flushing portion comprising the external flow channels may be entirely solid.

Each external flow channel may be aligned with a corresponding drainage aperture. The external flow channels may be evenly distributed around the circumference of the external flushing portion. The external flow channels may have the same shape and dimensions. The external flushing portion may be symmetrical about a plane extending along the longitudinal axis. The external flushing portion may be longer than the outlet portion. The external flow channels may be longitudinally separated from the, or each, drainage channel of the outlet portion (i.e., there may be a gap between the external flow channels and the, or each, drainage channel).

The outlet portion of the catheter may be shaped and configured for at least partial insertion into the urethra such that, in use, the plurality of drainage apertures may be positioned fully within the urethra and a seal may be formed at the urethral opening between the outlet portion and the urethral wall. The outlet portion may extend between 30 mm and 50 mm. In a preferred embodiment, the outlet portion may extend 40 mm. The outlet portion may extend from the outlet end towards the external flushing portion.

The catheter may further comprise a formation extending from an external surface of the main body and arranged, in use, to abut the base of the urethra upon insertion of the catheter into the urethra. The formation may be a ring, e.g., an annular ring. The formation, e.g., annular ring, may have a convex surface. A proximal face of the formation, e.g., annular ring, may curve from the outlet portion away from the insertion end. The distance between the formation and the insertion end may be fixed and correspond to a maximum desired insertion depth of the catheter into the urethra. The formation may form a ridge extending around the main body. The annular ring may be positioned between 80mm and 390mm from the insertion tip. For a female catheter, the annular ring may be between 80 mm and 100mm, preferably 90 mm from the insertion tip. For a male catheter, the annular ring may be between 330 mm and 390 mm, preferably 360 mm, from the insertion tip.

The insertion end may have a non-circular cross-section. For example, the insertion end may have a square or cruciform cross section (especially where four external flow channels are provided), or a triangular cross section (for example if three external flow channels are provided, pentagonal cross section (for example if five external flow channels are provided). The number of sides of the cross section of the insertion end, may (or may not) correspond to the number of external flow channels provided.

The external flow channels may be open faced in the radial direction so that, when inserted into the urethra, the catheter mates with the urethral wall to enclose the flow channels. The external flow channels may be defined by a plurality of walls which extend along the length of the main body. The plurality of walls may extend longitudinally. The plurality of walls may be straight. The plurality of walls may comprise a longitudinal axis. The cross-section of the plurality of walls 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 plurality of walls may extend radially from a central axis of the main body. The radially extending walls may comprise an outermost surface and respective opposing side walls. Providing rounded walls allows the cross-sectional area of the flow channels to be as wide as possible whilst also providing sufficient contact with the urethral wall such that the catheter does not move in use and provides improved comfort to the user. The combined area of the outer surface of the walls may be greater than the combined area of the open faces of the external flow channels. Alternatively, the combined area of the open faces of the external flow channels may be greater than the combined area of the outer surface of the walls. Preferably, the outer flow surface area created by the external flow 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 external flow channels may provide a fluid flow path from the insertion end to the outlet portion. The external flow channels may extend fully to the outlet portion. The external flow channels may extend continuously along the main body from the insertion end to the outlet portion.

The main body of the catheter may comprise an elongate member. The 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 between A80 and A90), thereby aiding insertion and maintaining the shape of the external flow channels in use.

The radially outermost surface of the plurality of walls may define an outside diameter of the catheter. The outside diameter may be constant along the length of the catheter. Hence, the overall width of the catheter may be constant along the length thereof. The cross-sectional area of the flow channels may be constant along the length of the catheter.

The outlet portion and the external flushing portion may be formed as a singular piece. The outlet portion and the external flushing portion may be formed as separate component pieces that are attached together.

The cross-section of the external flushing portion transverse to the longitudinal axis of the main body may comprise a continuously curved outermost surface. The number of external flow channels may be any suitable number for providing a described flow contact area and length. The catheter may comprise between two and six external flow channels. The catheter may comprise between three and five external flow channels. The catheter may comprise four external flow channels.

The outermost surfaces of the external flushing portion may be configured to contact the urethra along the full length thereof.

The outlet portion may be shaped and configured for the attachment of a separate funnel to an end portion thereof.

Alternatively, the outlet portion may comprise a funnel portion integrally formed therewith. In this alternative, the outlet portion may comprise a tubular portion with an upper face configured, in use, to abut the base of the urethra. The outlet portion and the external flushing portion may be concentric. In this alternative, the tubular portion may have a greater diameter than the external flushing portion. In this alternative, the outlet portion may be shaped and configured to encircle the urethra when the upper face abuts the base of the urethra. In this alternative, the outlet portion may comprise a recessed portion shaped and configured to capture urine flowing from the urethra between the external flushing portion and the urethral wall. In this alternative, the drainage apertures may be positioned at the base of the recessed portion such that the drainage apertures are outside the urethra, in use. In this alternative, the recessed portion may be shaped and configured to direct captured urine toward the drainage apertures.

The catheter may be a male urinary catheter or a female urinary catheter. The catheter may be a permanent or intermittent catheter. In a preferred embodiment, the catheter is an intermittent female urinary catheter.

For a female catheter the length of the catheter may be between 150 mm and 180 mm, preferably 160 mm.

For a male catheter, the length of the catheter may be between 360 mm and 420 mm, preferably 405 mm.

For a female catheter the length of the external flushing portion may be between 125 mm and 175 mm, preferably 145 mm. For a male catheter, the length of the external flushing portion may be between 300 mm and 350 mm, preferably 325 mm.

The diameter of the catheter may be between 2 mm and 6 mm depending on the intended user’s size requirements.

The depth of the external flow channels may be between 0.5mm and 2mm, preferably 1mm.

The present disclosure provides, in a second aspect, a method of manufacturing a catheter according to any aspect described herein by extrusion and/or injection moulding and/or 3D printing. The method may comprise the steps of extruding an external flushing portion of the catheter, extruding an outlet portion of the catheter, and attaching the external flushing portion to the outlet portion. The external flushing portion may be attached to the outlet portion by heat friction welding. The method may comprise the step of extruding the external flushing portion having a plurality of open-faced external flow channels formed in an external surface of the external flushing portion and extending the full length of the external flushing portion. The method may comprise the step of extruding the outlet portion with a solid tubular wall and having one or more drainage channels extending from an upper face of the outlet portion to a lower face thereof. Alternatively, the method may comprise the steps of forming the catheter in separate parts by injection moulding and welding the separate parts together e.g., by ultrasonic welding, to form the catheter.

The method may comprise the step of forming a plurality of drainage apertures through the external flushing portion at a junction between the outlet portion and the external flushing portion. The drainage apertures may be formed after the external flushing portion is attached to the outlet portion. Each of the plurality of drainage apertures may be formed by punching out material from the external flushing portion. Each drainage aperture may be formed at the terminal end of a corresponding external flow channel. The drainage apertures may be formed such that each external flow channel is in fluid communication with a drainage channel extending through the outlet portion.

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 a catheter comprising an external flushing portion and an outlet portion, the external flushing portion comprising a plurality of external flow channels formed in an external surface of the main body, the outlet portion comprising one or more drainage channels for the outflow of fluid from the catheter, wherein the external flow channels are each in fluid communication with a drainage channel of the outlet portion via a corresponding drainage aperture formed therebetween, and (ii) inserting the catheter into the bladder via the urethra until at least one external flow channel of the catheter extends into the bladder so that urine can drain from the bladder through the urethra along one or more, or each, external flow channel of the catheter. The outlet portion may be partially inserted into the urethra such that the drainage apertures are fully located inside the urethra. The outlet portion of the catheter may be attached to or comprise a funnel so that urine may flow from the bladder through the urethra along one or more, or each, external flow channel of the catheter and out through the funnel via one or more drainage channels of the outlet portion. Where the catheter comprises an insertion depth guide extending from the outlet portion of the catheter, the catheter may be inserted into the urethra until the insertion depth guide abuts the base of the urethra.

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. Brief Description of the Drawings

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 perspective view of a schematic representation of a catheter according to the present disclosure;

Figure 2 shows a first side view of the catheter of Figure 1;

Figure 3 shows a second side view of the catheter of Figure 1, the second side view circumferentially offset by 90 degrees from the first side view;

Figure 4 shows a cross sectional side view of the catheter of Figure 1; Figure 5 shows an enlarged perspective view of the outlet portion of the catheter of Figure 1;

Figure 6 shows an alternative enlarged perspective view of the outlet portion of the catheter of Figure 1 ;

Figure 7 shows an enlarged perspective view of the outlet portion shown in Figure 1 with an optional insertion depth guide extending therefrom;

Figure 8 shows a perspective view of a schematic representation of an alternative catheter according to the present disclosure with a funnel provided at the outlet end;

Figure 9 shows an enlarged perspective view of a junction between the external flushing portion and funnel portion of the catheter shown in Figure 8; and,

Figure 10 shows an underside view of the funnel of the catheter shown in Figure 8.

Detailed Description of the Invention

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 practiced 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, unless otherwise stated. Reference to the “transverse cross-section”, or simply “cross-section”, should be taken to be the cross-section which is transverse to the longitudinal axis of the main body, unless otherwise stated. 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 primarily intermittent female catheters. However, it will be appreciated that the inventive concepts and features described herein may be applied to indwelling urinary catheters and may be applied to male or female catheters whether intermittent or indwelling. Figure 1 shows a urinary catheter 1 comprising an elongate main body 2 having an insertion end 3 for insertion into a urethra and an outlet end 4 having an outlet portion 5 which provides an exit point for a flow of urine, when in use.

The main body 2 comprises an external flushing portion 6 extending from the insertion end 3 to the outlet portion 5. The external flushing portion 6 comprises a plurality of external flow channels 7 which provide a fluid flow path. The external flow channels 7 are provided in the external surface of the main body 2, are elongate and open faced in the radial direction so that, when inserted, the catheter 1 mates with the urethral wall (not shown) to enclose the flow channels 7. Hence, when inserted, the urethral wall is exposed to a flow of urine flowing along the external flow channels 7 of the external flushing portion 6.

The external flow channels 7 are defined by walls 8 which extend along the longitudinal axis 10 of the catheter 1 thereby forming one or more substantially straight walls 8 that are parallel with the longitudinal axis 10. The size and number of external flow channels 7 may vary according to the application and desired characteristics of the catheter 1. Typically, the size and number of the external flow channels 7 may be varied to alter the flow rate, velocity of the urine on the urethral wall, and the area of the urethral wall to be exposed to the urine. In the present embodiment, there are four external flow channels 7 and, correspondingly, four walls 8. The respective external flow channels 7 and walls 8 are substantially the same in shape and dimension and are substantially equally circumferentially distributed about the main body 2. Accordingly, the external flushing portion 6 is symmetrical about a plane extending along the longitudinal axis 10 and each external flow channel 7 and each wall 8 has a diametrically opposed counterpart.

It can be seen from the cross-sectional view of Figure 4 that the external flushing portion 6 comprises a solid central core 12. The four solid walls 8 extend radially from the central core 12 and each comprises an outermost surface 9 and opposing sidewalls which extend radially inwardly. The outermost surface 9 of the walls 8 is convex and curves about the circumference of the main body 2. The outer diameter of the external flushing portion 6 is defined by the distance between the outermost surfaces of two diametrically opposed walls 8. The radius of curvature of the outermost surface of a wall 8 is substantially equivalent to that of the outlet portion 5 such that the external flushing portion 6 and the outlet portion 5 share substantially the same outer diameter. Accordingly, the outer diameter is approximately constant along the entire length of the catheter 1 and the outermost surface of a wall 8 of the external flushing portion 6 is substantially aligned with the outermost surface of the outlet portion 5 such that no discernible ledge or step is formed at an interface therebetween in the longitudinal direction.

The opposing sidewalls of two adjacent walls 8 curve inwardly and toward one another to meet to form a continuously curved base portion of the external flow channel 7. The curved base portion of the external flow channel 7 is connected to the outermost surface 9 of each flanking wall 8 by a corresponding rounded transition 22. The rounded transition 22 and curving outermost surface 9 allows the catheter 1 to gain sufficient purchase on the wall of the urethra to ensure it remains in situ during use, whilst maximising the contact area of the flow channel 7. The depth of the external flow channels 7 is selected according to the catheter diameter. For a catheter of size CH 14 with a diameter of 4.66mm, the external flow channels 7 are approximately 1mm deep.

Although the external flow channels 7 are described as comprising a curved base portion extending to the outermost surface 9 of the walls 8 via a rounded transition 22, it will be appreciated that other channel shapes are possible and may provide adequate flushing of the urethra. For example, the external flow channels 7 may comprise a base and sidewalls that are angled to form a flow channel 7 with a V-shaped cross-section (which may be referred to as a wedge shape or tapered cross- section).

As can be seen in Figures 1 to 4, the external flushing portion 6 extends fully from the proximal end of the outlet portion 5 to the terminal end or tip 11 of the insertion end 3. Thus, the external flow channels 7 are configured to extend toward the insertion end 3 and terminate at the tip 11 of the insertion end 3 such that the external flow channels 7 are open at the insertion end 3 with no end wall. Providing the open-ended external flow channels 7 at the insertion end 3 means a flow path from the bladder through the urethra can be created as soon as the catheter 1 enters the bladder, thereby making the catheter 1 less sensitive to axial position in use (i.e., less sensitive to how far in the axial direction the catheter is inserted).

The cross-sectional area in the transverse direction of the open ends of the flow channels 7 may be the substantially same as that of the flow channel 7 along the length of the main body 2. However, in some embodiments, the open ends may comprise a flared, angled, or rounded portion such that the cross-section of the flow channel 5 expands at the open end or tapers radially inwardly. Adjusting the size and shape of the external flow channel 7 openings at the insertion end 3 of the catheter 1 may facilitate the flow of urine from the bladder into the external flow channels 7 and thereby encourage the emptying of the bladder.

In the present embodiment, both the external flow channels 7 and the walls 8 are curved at the terminal end of the insertion end 3 and taper toward the common rounded tip 11 of the catheter 1. Since the external flow channels 7 are open at the insertion end 3, the tip 11 of the catheter has a non-circular, cruciform (‘+’ shaped) cross-section which may serve to facilitate insertion of the catheter 1 into the urethra and bladder.

The walls 8 and external flow channels 7 extend fully from the insertion end 3 to the proximal end of the outlet portion 5 and terminate at a junction 13 therebetween. An arch shaped drainage aperture 14 or ‘doorway’ is formed at the base of each external flow channel 7 local to the junction 13 between the external flushing portion 6 and the outlet portion 5. In the present embodiment, the drainage apertures 14 extend axially and radially to a common space at the centre of the central axis of the catheter 1. Since each external flow channel 7 has a diametrically opposed counterpart, two opposed drainage apertures 14 may be aligned such that an open channel is formed entirely through the main body 2 of the catheter 1 from one side to the other in the transverse direction. Thus, the external flow channels 7 are longitudinally separated from the junction 13 of the outlet portion 5 (i.e., spaced apart in the longitudinal direction such that there is a gap between the external flow channels 7 and the outlet portion 5).

With reference to Figures 4 to 6, the outlet portion 5 comprises a solid tubular wall 15 extending from the distal end of the external flushing portion 6. The tubular wall 15 defines an outlet lumen 16 extending from an inlet 17 at the junction 13 between the external flushing portion 6 and the outlet portion 5 through to an outlet 18 provided in the end face 19 of the outlet portion 5 to form a nozzle for an exiting flow of urine from the catheter 1. The common space of the drainage apertures 14 is aligned with the inlet 17 such that the fluid flow path of the external flow channels 7 extends through the drainage apertures 14 and outlet lumen 16, thereby allowing urine to exit the catheter via the outlet 18.

As shown in Figure 5, the drainage apertures 14 are formed such that a substantially planar end face 20 is formed at the terminal end of each external flow channel 7 and extends radially inwardly toward the central axis of the catheter 1. However, it will be appreciated that the end face 16 at the terminal end of each external flow channel 7 need not extend radially inwardly and transverse to the longitudinal axis and may instead be angled to form a ramp toward the outlet lumen 16, thereby guiding urine to flow from the external flow channels 7 into the outlet lumen 16.

The outlet portion 5 is shaped and configured for at least partial insertion into the urethra together with the external flushing portion 6 so that the drainage apertures 14 may be positioned within the urethra. Accordingly, the diameter of the outlet portion 5 is less than the diameter of the urethra of the intended user. When the outlet portion 5 is partially inserted and the drainage apertures 14 are appropriately positioned within the urethra, urine flowing along the external flow channels 7 between the external flushing portion 6 and the urethral wall may enter the outlet lumen 16 through the drainage apertures 14 for the outflow of urine from the catheter 1 without leaking from between the outlet portion 5 and urethral opening.

Whilst in the present embodiment a single common outlet lumen 16 is provided for drainage of urine from the external flow channels 7, it will be appreciated that the outlet portion 5 may take a different form and may comprise more than one outlet which may or may not be provided in the external end face 19 of the outlet portion. For example, the outlet portion 5 may comprise a plurality of separate, non-converging drainage channels extending fully through the outlet portion 5 to a corresponding exit aperture. In such an example, each drainage channel may be in fluid communication with a corresponding external flow channel 7 such that multiple independent, nonconverging fluid flow paths are formed from the insertion end 3 through to the terminal end i.e., the endmost face of the catheter 1. In doing so, urine may flow in multiple streams in a broadly axial direction from the insertion end 3 to the outlet end 4 into a funnel or receptacle such as a toilet bowl.

Referring to Figure 7, the outlet portion 5 may optionally include a formation that provides an insertion depth guide 24, which in this embodiment is a formation in the form of an annular ring. The annular ring 24 may have a convex outer surface extending from the outlet wall 15 and fully around the circumference of the outlet portion 5. The annular ring 24 may be integrally formed with the outlet wall 15 and shaped such that the proximal face 26 curves from the wall 15 of the outlet portion 5 away from the insertion end 4. The annular ring 24 is spaced apart from the end face 19 of the outlet portion 5 and positioned a distance from the terminal end 11 of the catheter 1 that represents a maximum desired insertion depth of the catheter 1 into the urethra and, ultimately, the bladder. For example, the annular ring may be positioned approximately 10mm from the junction 13 between the external flow portion 6 and the outlet portion 5 so that the annular ring 24 is between 80mm and 390mm from the tip depending on whether the catheter is a male or female type. For a female catheter, the annular ring may be between 80 mm and 100 mm from the terminal end of the insertion end. For a male catheter, the annular ring may be between 330 mm and 390 mm from the terminal end of the insertion end.

Accordingly, the annular ring 24 is shaped and configured to form a relatively gentle ridge that is positioned, in use, to abut the base of the urethra and provide a nonintrusive, tactile and/or visual feedback to the user to indicate when the drainage apertures 14 are appropriately positioned within the urethra and the catheter 1 has reached or is approaching its maximum desired insertion depth.

The annular ring 24 may also be arranged to form an abutment for a separate funnel attachment (not shown) that may be inserted over the wall 15 of the outlet portion 5 from the end face 19 thereof. The distance between the annular ring 24 and end face 19 of the outlet portion 5 may therefore be equivalent to the maximum desired insertion distance for the funnel attachment over the wall 15 of the outlet portion 5 and assist a user in correctly positioning a funnel for the outflow of urine from the catheter 1 without leakage.

Whilst the outlet portion 5 may be configured for the attachment of a separate funnel at the terminal end thereof, it will be appreciated that a funnel may be incorporated into, and integrally formed with, the outlet portion. Referring to Fig. 8, an alternative catheter 101 comprises an external flushing portion 106 having the same general form as that described above with four external flow channels 107 and four walls 108 extending fully to the insertion tip 111 and together shaped to have a cruciform cross-section in the transverse direction. In this alternative embodiment, the outlet portion 105 comprises a funnel portion 126 forming a conical cavity 128 which expands toward an outlet at the end face of the funnel portion 126 for the outflow of urine from the catheter 1.

The outlet portion 105 comprises a substantially tubular solid wall portion 115 with a diameter greater than that of the external flushing portion 106. The proximal side of the outlet portion 105 comprises an annular face 130 encircling the external flushing portion 106 and extending to an internal recessed portion 132 with a tapered inner wall 134. The recessed portion 132 is shaped to capture urine flowing between the external flushing portion 106 and the urethral wall and direct the urine toward the lower face of the recessed portion 132. Four drainage apertures 114 are formed at the terminal ends of the corresponding external flow channels 107 and into the canonical cavity 128 of the funnel portion 126.

The external flushing portion 106 is shaped and configured to be inserted into the urethra until the annular face 130 of the outlet portion 105 abuts the base of the urethra and encircles the urethra to capture urine flowing therefrom and direct it to the drainage apertures 114. Accordingly, in the present embodiment, the outlet portion 105 is not shaped and configured to be partially inserted into the urethra and there is no requirement for a depth insertion guide extending from the outer wall 115 of the outlet portion 105. A flange 134 extends from the outlet portion 105 and is provided to allow handling and positioning of the catheter 1 when being inserted into and removed from the urethra.

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, polyether block amide, thermoplastic vulcanizates, thermoplastic copolyesters, thermoplastic polyamides, and water disintegrable or enzymatically hydrolysable material, or combinations, blends or copolymers of any of the above materials.

In preferred embodiments, the catheter is formed of a material of the group comprising: polyolefins, polyesters, poly acrylates, polyamides, thermoplastic elastomeric material, polyether block amide, thermoplastic vulcanizates, thermoplastic copolyesters, thermoplastic polyamides, fluororubber, and water disintegrable or enzymatically hydrolysable material or combinations, blends or co-polymers of any of the above materials.

In some embodiments, said water disintegrable or enzymatically hydrolysable material comprises a material of the group comprising: polyvinyl alcohol, extrudable polyvinyl alcohol, poly aery lie 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, melamine-formaldehyde 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. 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.