JP7183252B2 - catheter assembly - Google Patents

Description

TECHNICAL FIELD The present invention relates to a catheter assembly having a function of suppressing bending of a catheter.

Japanese National Publication of International Patent Application No. 2013-529111 discloses a catheter assembly having a double structure needle in which an inner needle is inserted into the catheter. In this catheter assembly, the catheter and the inner needle are elongated in order to insert the catheter deeply into the patient's body. The user of the catheter assembly advances the catheter relative to the inner needle in the state of puncture with the double structure needle to advance the catheter into the blood vessel, and further removes the inner needle from the catheter, thereby moving the catheter to the patient side. detained in

By the way, the catheter assembly disclosed in Japanese Patent Application Laid-Open No. 2013-529111 disengages the catheter and the catheter hub from the inner needle and the needle hub by vertically separating the tip side of the inner needle hub when the catheter advances. It is configured. However, with such a configuration, the dual structure needle extends in an unsupported (free) state with respect to the separated inner needle hub when the catheter is advanced. Therefore, the double structure needle easily bends when receiving a reaction force from the patient. In some cases, the deflection may cause the needle tip to slip out of the patient's insertion site, and the needle tip may puncture the patient again.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a catheter assembly capable of suppressing bending of an inner needle during movement of the catheter.

In order to achieve the above object, the present invention provides a catheter, a catheter hub for fixing and holding the catheter, an inner needle detachably inserted into the catheter, a tip for fixing and holding the inner needle, and a tip. an inner needle hub having a portion, wherein a support member is arranged at the distal end portion of the inner needle hub to suppress deflection of the inner needle while allowing the catheter to slide, The support member is integrally separated from the inner needle hub as the catheter hub moves.

Moreover, it is preferable that the catheter hub and the support member have an engaging mechanism that engages the catheter hub and the support member when the catheter hub moves to the distal end portion.

In addition to the above configuration, the support member is configured to be integrated by accommodating a portion of the catheter hub from the proximal end inside, and the engagement mechanism is the outer peripheral surface of the catheter hub and the support member. It is preferable that it is a structure in which the inner peripheral surface is fitted.

Alternatively, the support member is configured to be integrated by accommodating a portion of the catheter hub inside from the proximal end, and the engagement mechanism is the outer peripheral surface of the catheter hub and the inner peripheral surface of the support member. A structure in which a convex portion provided on the other side is inserted into a concave portion provided on one side may be employed.

In this case, the engagement mechanism may engage the catheter hub at a plurality of axial positions of the support member.

Moreover, it is preferable that the support member has a notch extending a predetermined length in the axial direction from the base end.

A catheter operating member for operating movement of the catheter and the catheter hub may be provided.

Furthermore, the support member can be configured to have a portion that is detachably engaged with the inner needle hub.

The portion that releasably engages the inner needle hub may include a pair of wings.

Alternatively, the portion detachably engaged with the inner needle hub includes a hook portion that hooks on the inner needle hub in an initial state before the inner needle is punctured, and the hook portion moves the catheter hub. It can also be configured to release the catching with the inner needle hub in conjunction with .

Furthermore, the inner needle hub has a slot extending from a predetermined position in the axial direction of the inner needle hub to the distal end, and a part of the support member is inserted into the slot to allow the support member to It is preferable that the movement can be guided.

In order to achieve the above object, the present invention also provides a catheter, a catheter hub for fixing and holding the catheter, an inner needle detachably inserted into the catheter, and fixing and holding the inner needle, and an inner needle hub having a distal end portion, and a portion disposed at the distal end portion of the inner needle hub and releasably engaged with the inner needle hub, the inner needle being slidable while the catheter is slidable. and a support member that suppresses bending.

According to the present invention, the catheter assembly has a structure in which the support member arranged at the distal end of the inner needle hub is detached together with the movement of the catheter hub, thereby greatly improving the handleability of the catheter assembly. be able to. That is, the support member can suppress the bending of the inner needle inserted into the catheter while contacting the outer peripheral surface of the catheter when the catheter and the inner needle are inserted into the living body or when the catheter is inserted into the blood vessel. .

1 is a perspective view showing the overall configuration of a catheter assembly according to a first embodiment of the present invention; FIG. FIG. 2A is a plan view showing a support member; FIG. FIG. 2B is a side view of the support member; FIG. 3A is a plan view showing a state in which the catheter hub is engaged with the support member; FIG. 3B is a front view showing a state in which the catheter hub is engaged with the support member; FIG. 4A is a side view showing the distal end portion of the inner needle hub with the support member arranged. FIG. 4B is a side view showing a state in which the catheter hub and support member are detached from the inner needle hub; 5A is a first explanatory view showing the operation of the catheter assembly of FIG. 1; FIG. 5B is a second explanatory view showing the operation of the catheter assembly of FIG. 1; FIG. 5C is a third explanatory view showing the operation of the catheter assembly of FIG. 1; FIG. 6A is a fourth explanatory view showing the operation of the catheter assembly of FIG. 1; FIG. 6B is a fifth explanatory view showing the operation of the catheter assembly of FIG. 1; FIG. FIG. 7A is a side view showing a catheter assembly according to a second embodiment; FIG. FIG. 7B is a front view showing an engagement state between the catheter hub and the catheter operating member; FIG. 7C is a side view showing the engagement state of the catheter hub and catheter operating member. 8A is a first explanatory view showing the operation of the catheter assembly of FIG. 7A; FIG. FIG. 8B is a second illustration showing the operation of the catheter assembly of FIG. 7A. FIG. 8C is a third illustration showing the operation of the catheter assembly of FIG. 7A. 9A is a plan view showing a support member of a catheter assembly according to the third embodiment; FIG. Figure 9B is a side view of the support member of Figure 9A. 9C is a top cross-sectional view of the support member of FIG. 9A. FIG. 10A is a plan view showing the catheter hub of the catheter assembly; FIG. FIG. 10B is a side view for explaining the state of engagement between the catheter hub and the support member. FIG. 11 is a perspective view showing a catheter hub and support members of a catheter assembly according to a fourth embodiment; 12A is a schematic side view of a catheter assembly having the catheter hub and support member of FIG. 11; FIG. Figure 12B is a schematic plan view of the catheter assembly of Figure 12A. 13A is a schematic side view showing movement of the catheter hub of the catheter assembly of FIG. 12A; FIG. Figure 13B is a schematic plan view of the catheter assembly of Figure 13A. 14A is a schematic side view showing movement of the catheter hub continued from FIG. 13A; FIG. Figure 14B is a schematic plan view of the catheter assembly of Figure 14A.

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[First Embodiment]
A catheter assembly 10A according to the first embodiment, as shown in FIG. 1, has a catheter 12 that is inserted into the patient's body from the outside. do. Catheter 12 is longer than peripheral venous catheters (eg, as applied to central venous catheters, PICCs, midline catheters, etc.). The catheter 12 may be configured as a peripheral venous catheter, or may be configured not only as a venous catheter but also as an artery such as a peripheral arterial catheter.

In addition to the catheter 12 described above, the catheter assembly 10A includes an inner needle 14 inserted into the catheter 12, a catheter hub 20 fixedly holding the catheter 12, and an inner needle hub 30 fixedly holding the inner needle 14. As shown in FIG. The catheter assembly 10A constitutes a double structure needle 16 in which the catheter 12 and the inner needle 14 overlap in a state before use (initial state). In addition, the catheter assembly 10A includes a support member 40 that slidably supports the double structure needle 16 (catheter 12) at the distal end portion 31 of the inner needle hub 30. As shown in FIG.

Specifically, the catheter 12 of the catheter assembly 10A is moderately flexible and includes an axially extending lumen 12a therein. The total length of the catheter 12 is not particularly limited, but may be, for example, 14 to 500 mm, preferably 30 to 400 mm, or more preferably 76 to 200 mm.

The constituent material of the catheter 12 is preferably a soft resin material. Examples include olefin resins such as polyethylene and polypropylene, mixtures thereof, polyurethane, polyester, polyamide, polyether nylon resins, and mixtures of olefin resins and ethylene/vinyl acetate copolymers.

The proximal end of catheter 12 is secured to the distal end within catheter hub 20 by any suitable securing means such as crimping, fusing, gluing, insert molding, or the like. The catheter hub 20 is exposed on the patient's skin while the catheter 12 is inserted into the patient's blood vessel, and is attached together with the support member 40 with a tape or the like and indwelled. This catheter hub 20 is connected to other medical devices (infusion and blood transfusion tubes).

The catheter hub 20 is formed in a tubular shape that is harder than the catheter 12 . The catheter hub 20 includes a distal tapered portion 21 that tapers toward the distal direction, and a proximal trunk portion 22 that continues to the proximal end of the distal tapered portion 21 and extends with a constant thickness. An operation tab 23 projecting radially outward is provided on the proximal side outer peripheral surface of the proximal trunk portion 22 . Also, although illustration is omitted, the catheter hub 20 may be provided with a flange for engaging with other medical equipment.

Inside the catheter hub 20, an internal space 20a communicating with the lumen 12a of the catheter 12 is formed. The inner space 20a communicates with a proximal end opening 20b provided at the proximal end of the catheter hub 20. As shown in FIG. In this internal space 20a, there are provided a hemostasis valve (not shown) for preventing leakage of backflow of blood when the double structure needle 16 is punctured, and a plug (not shown) for penetrating the hemostasis valve and allowing infusion as the connector of the infusion tube is inserted. etc. may be accommodated.

In the initial state, the catheter hub 20 is accommodated in the inner needle hub 30 so as to be freely advanceable and retractable, and in the accommodated state, the operation tab 23 faces upward. The operation tab 23 is formed to have a height that does not protrude from the upper surface of the inner needle hub 30 and a certain width in the circumferential direction so that the finger of the user can easily touch it. In addition, the operation tab 23 may protrude greatly so as to be exposed upward from the upper surface of the inner needle hub 30 .

The constituent material of the catheter hub 20 is not particularly limited, and thermoplastic resins such as polypropylene, polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer may be applied.

On the other hand, the inner needle 14 is configured as a hollow tubular body having rigidity capable of puncturing the skin of a living body, and has a sharp needle tip 15 at its tip. An axially extending hollow portion 14 a is provided inside the inner needle 14 , and the hollow portion 14 a communicates with a tip opening 14 b provided in the needle tip 15 .

Examples of the constituent material of the inner needle 14 include metal materials such as stainless steel, aluminum or aluminum alloys, titanium or titanium alloys, hard resins, and ceramics. The inner needle 14 is firmly fixed to the inner needle hub 30 by suitable fixing means such as fusion bonding, adhesion, insert molding, or the like.

The inner needle hub 30 constitutes a grip portion that is gripped by users such as doctors and nurses, and is configured to be integrally handled with the inner needle 14 . The inner needle hub 30 is a rectangular tube-shaped accommodating member having an accommodating space 30a inside which can accommodate the catheter hub 20 and the support member 40 . Specifically, in a cross-sectional view perpendicular to the axial direction of the inner needle hub 30 , the inner needle hub 30 includes a lower wall 32 , an upper wall 33 facing the lower wall 32 , and between both sides of the lower wall 32 and the upper wall 33 . , and a pair of side walls 34 extending to surround the housing space 30a. A proximal end wall 35 for fixing and holding the inner needle 14 is provided at the proximal end of the inner needle hub 30, and the proximal end wall 35 closes the accommodation space 30a. In addition, the inner needle hub 30 may be configured to include a needle holding portion for fixing the inner needle 14 in the housing space 30a.

A lower wall 32 of the inner needle hub 30 has a predetermined thickness and is formed in a continuous plate shape along the axial direction (longitudinal direction) of the inner needle hub 30 . Alternatively, the lower wall 32 is formed in a shape (for example, an arc shape that fits the cylindrical shape of the catheter hub 20) that guides the advance and retreat of the catheter hub 20 on the proximal side of the distal end portion 31 of the inner needle hub 30. may

The upper wall 33 is formed in a flat plate shape like the lower wall 32 and has a guide groove portion 36 extending from a midpoint in the axial direction of the inner needle hub 30 to the tip. The guide groove portion 36 communicates between the housing space 30a and the outside of the inner needle hub 30, and in the initial state (the state before use, in which the needle tip 15 of the inner needle 14 protrudes from the tip of the catheter 12), the catheter An operating tab 23 of hub 20 is located. That is, the guide groove portion 36 has a function of allowing the user to touch the operation tab 23 and guiding the forward/backward movement of the operation tab 23 . The guide groove portion 36 is formed to have a length corresponding to the movement range of the catheter hub 20 (dimensions of the catheter 12) within the inner needle hub 30, and has a width capable of regulating the withdrawal of the catheter hub 20 from the housing space 30a. is formed in An inner edge 33a of the upper wall 33 forming the guide groove 36 is formed in a tapered shape that widens in the width direction from the side of the accommodation space 30a toward the outside, making it easier for the user's finger to enter. The proximal end of the guide groove portion 36 is provided at a position where the operation tab 23 of the catheter hub 20 abuts in the initial state and the catheter hub 20 does not move further toward the proximal end. It is also possible to provide a means for restricting the movement of the catheter hub 20 in the axial direction, such as a projection, inside the inner needle hub 30 .

A pair of side walls 34 are formed in a flat plate shape and have slots 37 for holding the support member 40 at the distal end portion 31 of the inner needle hub 30 . The slot 37 is formed with a length corresponding to the entire length of the support member 40 and extends to the tip of the inner needle hub 30 (side wall 34). The slots 37 have the function of locking the wings 42 of the support member 40 to be described later, and releasing the locking of the wings 42 when receiving pressure from the support member 40 in the distal direction.

For example, the inner wall surface of the slot 37 has an engagement protrusion 37a that slightly protrudes on the distal end side of the wing 42 in the initial state. The engagement convex portion 37a is formed at a steep angle on the base end side facing the wing 42 in the initial state, and is formed at a gentle angle on the opposite side. , the engagement force is changed depending on whether the support member is retracted in the proximal direction. Note that the inner wall surface of the slot 37 may be formed to have a groove width that does not include the engaging protrusion 37a and that provides an appropriate frictional force to the wing 42 in the initial state.

The inner needle hub 30 constitutes a portion that is gripped by the user, and thus can also be called a grip portion. The inner needle hub 30, including the portion that holds the inner needle 14 fixedly, may be composed of one member or may be composed of a plurality of members. In this case, the inner needle hub 30 includes the member including the portion for fixing and holding the inner needle 14 and the aforementioned member. The inner needle hub 30 is a rectangular tube-shaped housing member, and the wall structure of the lower wall 32, the upper wall 33, and the pair of side walls 34 has been described. It can also be configured as a circular or oval wall. In this case, the partially or wholly circular or elliptical walls are to be read as the above descriptions of the configurations (lower wall 32, upper wall 33 and pair of side walls 34) at substantially corresponding positions.

The support member 40 is held on the distal end portion 31 side of the inner needle hub 30 in the initial state. This support member 40 supports the inner needle 14 via the catheter 12 when the double structure needle 16 (catheter 12) is punctured or when the catheter 12 advances, suppresses the bending of the inner needle 14, and furthermore, the catheter hub 20. As it moves, it separates from the inner needle hub 30 together with the catheter hub 20 (see FIG. 6B). After detachment, the support member 40 remains in the patient together with the catheter 12 and catheter hub 20 .

As shown in FIGS. 2A and 2B, the support member 40 has a central tube 41 and a pair of wings 42 projecting outward in the width direction from the outer peripheral surface of the central tube 41 . The central cylinder 41 is formed so as to protrude upward from a flat lower surface in a front view so as to draw a substantially semicircular shape. The central tube 41 includes, in a plan view, a distal side tubular portion 43 tapering toward the distal direction, and a proximal side tubular portion 44 connected to the proximal end of the distal side tubular portion 43 and connected to a pair of wings 42 . , has

The central tube 41 has a space 45 that can accommodate the catheter hub 20 from the base end side tube part 44 to the distal end side tube part 43 . The space portion 45 communicates with a base end opening 45 a provided at the base end of the central tube 41 and with an insertion support hole 45 c formed at the center of the tip side tube portion 43 . As shown in FIG. 3A, the space 45 is preferably designed to have an appropriate shape corresponding to the outer shape of the catheter hub 20 to be inserted. It is shaped like a funnel with a gradually decreasing diameter.

The catheter hub 20 and the support member 40 have an engagement mechanism 18 that engages (integrates) with each other when the catheter hub 20 moves to the distal end portion 31 of the inner needle hub 30 . In the present embodiment, the engagement mechanism 18 has a structure in which the outer peripheral surface of the catheter hub 20 and the inner peripheral surface forming the space 45 of the support member 40 are fitted with an appropriate frictional force.

In addition, a notch 46 having a predetermined axial length and width from the proximal end to the distal end and having an arcuate shape on the distal end side is provided in the proximal side cylindrical portion 44 . The base end side of the central tube 41 is easily elastically deformed radially outward by the notch 46 . The engagement mechanism 18 is not limited to friction fitting, and for example, one of the catheter hub 20 and the support member 40 may be provided with a protrusion and the other may be provided with a recess. (see also FIGS. 9C and 10A).

On the other hand, the insertion support hole 45c extends from the space 45 to the tip of the central tube 41 (tip opening 45b). The diameter of the insertion support hole 45c is slightly larger than the outer diameter of the catheter 12 and smaller than the diameter of the tip of the catheter hub 20. As shown in FIG. In other words, the wall of the support member 40 forming the insertion support hole 45c forms a small gap with the catheter 12, allowing the catheter 12 to slide freely, and the inner needle 14 to move radially outward ( bending).

As shown in FIGS. 2A to 4B, the pair of wings 42 of the support member 40 are formed so as to have the same axial length and sufficient thickness as the base end side tubular portion 44 in plan view. be. The support member 40 is initially positioned with respect to the distal end of the inner needle hub 30 by having the pair of wings 42 accommodated in the pair of slots 37 of the inner needle hub 30 . Each wing 42 protrudes outward in the width direction from the pair of side walls 34 of the inner needle hub 30 .

The pair of wings 42 are connected to the lower side of the central tube 41 so that the lower surface of the central tube 41 and the lower surface of each wing 42 are flush with each other when viewed from the front. As a result, when the support member 40 is placed on the patient side, it can be placed on the patient's body surface so that the entire lower surfaces of the central tube 41 and the wings 42 are in surface contact, and presses a narrow range of the body surface. can be suppressed.

The material that constitutes the support member 40 is not particularly limited, and for example, the materials listed for the catheter hub 20 may be applied. In addition, in order to prevent kinking of the catheter 12, the portion forming the insertion support hole 45c in the distal side cylindrical portion 43 of the support member 40 is made more flexible than the other portion (the portion closer to the proximal end than the insertion support hole 45c). It is preferably a configured flexible portion 47 . Note that the support member 40 as a whole may be configured to be more flexible than the catheter hub 20 and the like.

The catheter assembly 10A has the initial state shown in FIGS. 1 and 5A by appropriately assembling the above members. In the initial state, the support member 40 is arranged at the distal end portion 31 of the inner needle hub 30 and is capable of contacting and supporting the double structure needle 16 with the inner needle 14 inserted into the catheter 12 . The catheter hub 20 is accommodated on the proximal end side of the inner needle hub 30 with the inner needle 14 inserted into the inner space 20 a , and the operation tab 23 is arranged in the guide groove portion 36 .

The catheter assembly 10A according to the first embodiment is basically formed as described above, and the operation thereof will be described below.

The catheter assembly 10A is used when constructing an introduction section for blood transfusion or infusion as described above. In use, the user grasps and manipulates the inner needle hub 30 to puncture the dual structure needle 16 into the patient. During puncture, the support member 40 supports the double structure needle 16 from the outside and suppresses bending of the double structure needle 16 .

In the puncture state of the double structure needle 16, as shown in FIG. 5B, the user pushes out the catheter hub 20 by advancing the operation tab 23 of the catheter hub 20 in the distal direction, and inserts the catheter 12 into the blood vessel. To go. At this time, the support member 40 prevents bending of the inner needle 14 through the catheter 12 while guiding the movement of the catheter 12 .

As shown in FIG. 5C , when the catheter hub 20 moves to the vicinity of the distal end of the inner needle hub 30 as it advances, it enters the space 45 of the support member 40 . At this time, the pair of wings 42 arranged in the pair of slots 37 have an engaging force slightly higher than the engaging force of the engaging projections 37a, so that the catheter hub 20 is held in place by the support member 40. It fits well on the support member 40 . After that, when the support member 40 receives an advancing force from the catheter hub 20, the engagement between the engaging convex portion 37a and the wing 42 is disengaged, and the wing 42 moves in the slot 37 of the inner needle hub 30 in the distal direction. .

Further, as shown in FIG. 6A, the catheter assembly 10A can once retract the catheter 12 according to the user's intention. Even after the catheter hub 20 and the support member 40 are engaged with each other, by simply returning the operation tab 23 of the catheter hub 20 in the proximal direction, the pair of wings 42 climbs over the engaging projections 37a and moves into the deep portion of the slot 37. , the backward movement of the support member 40 is regulated. Therefore, if the catheter hub 20 is pushed back in the proximal direction, the engagement between the catheter hub 20 and the support member 40 is smoothly released.

Then, the user detaches the catheter hub 20 and the support member 40 together from the inner needle hub 30 as the catheter hub 20 is advanced or the inner needle hub 30 is retracted as shown in FIG. 6B. As a result, the support member 40 remains engaged with the catheter hub 20 and remains on the body surface of the patient as an indwelling body. At this time, the support member 40 has a pair of wings 42 to which a tape or the like is attached, so that the catheter 12 and the catheter hub 20 can be favorably indwelled.

As described above, in the catheter assembly 10A according to the first embodiment, the support member 40 arranged at the distal end portion 31 of the inner needle hub 30 is integrally detached as the catheter hub 20 moves. The handleability can be greatly improved. That is, the support member 40 suppresses bending of the inner needle 14 through the catheter 12 while allowing the catheter 12 to slide when the catheter 12 and the inner needle 14 are punctured into a living body or when the catheter 12 is inserted into a blood vessel. . This support by the support member 40 continues well until the catheter 12 is moved onto the support member 40 . Moreover, since the support member 40 is integrally separated from the inner needle hub 30 as the catheter hub 20 moves, the inner needle 14 can be easily pulled out from the catheter hub 20 . Therefore, the catheter assembly 10A can be easily operated, and the efficiency of the treatment by the user can be improved.

Further, in the catheter assembly 10A, by engaging the catheter hub 20 and the support member 40 with the engagement mechanism 18, both members can be more firmly integrated. Then, the catheter hub 20 and the support member 40 can be stably indwelled on the patient side as an indwelling body in a state of being assembled.

Furthermore, since the engagement mechanism 18 has a structure in which the outer peripheral surface of the catheter hub 20 and the inner peripheral surface of the support member 40 are fitted together, both members can be engaged by a simple operation of inserting the catheter hub 20 into the support member 40 . Engagement can be achieved.

Furthermore, the catheter assembly 10A has the notch 46 in the support member 40, so that the proximal end portion of the support member 40 is easily elastically deformed when the catheter hub 20 enters the support member 40. . As a result, the catheter hub 20 can be smoothly moved to the fitting position and fitted with the support member 40 with an appropriate frictional force.

Here, since the catheter assembly 10A has a portion where the support member 40 engages with the inner needle hub 30, it is possible to strongly prevent the support member 40 from coming off in the initial state.

Since the support member 40 includes a pair of wings 42 as a portion that engages with the inner needle hub 30, it is possible to easily and stably maintain the arrangement state of the support member 40 by the inner needle hub 30. . Moreover, the wing 42 can be used as a place to which a tape or the like can be applied to reduce the pressure area when the wing 42 is left on the body surface of the patient after detachment from the inner needle hub 30 .

Then, in the catheter assembly 10A, a part of the support member 40 (the pair of wings 42) is inserted into the slot 37 of the inner needle hub 30 and guided, so that the support member 40 can be moved smoothly. Detachment of the support member 40 from 30 can be further facilitated.

It should be noted that the catheter assembly 10A according to the present invention is not limited to the above embodiment, and various modifications and applications can be made. For example, the support member 40 is not limited to a cylindrical shape that can accommodate the catheter hub 20 , and may have any structure that can be engaged with the proximal end portion of the catheter 12 or the distal end of the catheter hub 20 . As an example, the proximal end portion of the catheter 12 may be thickened and the support member 40 may be engaged with this proximal end portion, so that the support member 40 may function as a strain relief to prevent kinking of the catheter 12. good.

Further, the support member 40 (engagement mechanism 18) may employ a structure that hooks onto the distal end of the catheter hub 20, a structure that is attached to the catheter hub 20, or the like. Alternatively, the support member 40 may be shaped to accommodate the entire catheter hub 20 .

The support member 40 in the present embodiment has been described as having a pair of wings 42 in terms of maintaining the arrangement of the support member 40 by the inner needle hub 30 and using it when indwelling on the patient's body surface. However, instead of the pair of wings 42, projections guided by slots 37 of the inner needle hub 30 or grooves provided on the inner surface of the side wall 34 may be used. Such projections can reliably maintain the arrangement of the support member 40 by the inner needle hub 30 . In this embodiment, protrusions may be provided on side wall 34 of inner needle hub 30 and grooves may be provided on support member 40 .

[Second embodiment]
As shown in FIGS. 7A to 7C, the catheter assembly 10B according to the second embodiment is provided with a catheter operation member 50 for operating the forward and backward movement of the catheter 12 and the catheter hub 20, unlike the first embodiment. It is different from the catheter assembly 10A according to. In the following description, elements having the same configurations or functions as those of the above-described embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

Specifically, the catheter operation member 50 comprises a connecting portion 51 connected to the outer peripheral surface of the catheter hub 20, a connecting neck portion 52 projecting from the connecting portion 51, and a portion connected to the connecting neck portion 52 and operated by the user. and an operation unit 53 .

The connecting portion 51 of the catheter operation member 50 is housed in the housing space 30a of the inner needle hub 30 together with the catheter hub 20 in the initial state. The connecting portion 51 is formed in a rectangular shape corresponding to the cross-sectional shape of the housing space 30a of the inner needle hub 30 when viewed from the front. Also, the connecting portion 51 has a shorter axial length than the proximal barrel portion 22 of the catheter hub 20 . Inside the connecting portion 51, a holding space 51a is formed which has a diameter equal to or slightly smaller than the outer diameter of the catheter hub 20. As shown in FIG. The catheter hub 20 inserted into the holding space 51a is engaged and held with the connection portion 51 with a moderate frictional force. The connecting portion 51 allows the catheter hub 20 to be removed downward by elastically opening the pair of leg portions 51b forming the holding space 51a in the width direction.

A connecting neck portion 52 of the catheter operating member 50 is formed narrower than the groove width of the guide groove portion 36 (see FIG. 1) of the inner needle hub 30 and connects the connecting portion 51 and the operating portion 53 . This exposes the operating portion 53 to the outside of the inner needle hub 30 .

The operating portion 53 is formed in a block shape that is wider than the guide groove portion 36 of the inner needle hub 30 above the inner needle hub 30 . Further, the operating portion 53 is formed so as to overlap the catheter hub 20 in plan view by extending in the distal direction from the connecting portion of the connecting neck portion 52 . This allows the fingers of the user holding the inner needle hub 30 to easily reach the operation portion 53 .

On the other hand, the catheter hub 20 has a restricting projection 22a on the outer peripheral surface of the base end trunk portion 22 that restricts movement of the connection portion 51 of the catheter operating member 50 in the distal direction. That is, the connecting portion 51 is sandwiched between the restricting protrusion 22a and the operating tab 23, and is restricted from moving in the axial direction with respect to the catheter hub 20. As shown in FIG.

In addition, in the catheter assembly 10B, the support member 40 (engagement mechanism 18) that supports the double structure needle 16 (catheter 12) is located at the catheter hub 20 on the distal end side of the connection point of the connection portion 51 of the catheter operation member 50. are accommodated and engaged to integrate the support member 40 and the catheter hub 20 .

The catheter assembly 10B according to the second embodiment is basically configured as described above. As shown in FIGS. 8A and 8B, this catheter assembly 10B is basically the same as the first embodiment, except that the user operates the catheter operation member 50 to advance or retract the catheter 12 and catheter hub 20. It performs the same operation as the catheter assembly 10A according to the embodiment. That is, the catheter assembly 10B can prevent the inner needle 14 from bending due to the support member 40 when the catheter 12 and the catheter hub 20 are moved even when the catheter operation member 50 is provided. In addition, the catheter hub 20 engages with the support member 40 when it advances, so that the catheter hub 20 and the support member 40 can be smoothly detached from the inner needle hub 30 .

Also, as shown in FIG. 8C, the catheter operation member 50 is removed from the catheter hub 20 by the user after the catheter hub 20 is detached from the inner needle 14 . As a result, the indwelling body composed of the catheter 12, the catheter hub 20 and the support member 40 is indwelled on the patient side.

It should be noted that the catheter operation member 50 is not limited to the configuration described above, and various modifications can be made. For example, the connecting portion 51 of the catheter operation member 50 is not only connected to the outer peripheral surface of the catheter hub 20, but also inserted into the internal space 20a through the proximal end opening 20b (see FIG. 7A) in the catheter hub 20 and fitted. It may be a configuration or the like. Further, the catheter operation member 50 may be integrated with the support member 40 by engaging with the support member 40 when advanced, and left in the patient. Furthermore, the catheter operation member 50 may be configured to be able to be hooked on the needle tip 15 of the inner needle 14 and may not be detachable from the waste body. In this case, the catheter operation member 50 may function as a safety member that prevents accidental pricking of the inner needle 14 by covering the needle tip 15 of the inner needle 14 when the indwelling body is removed.

[Third Embodiment]
In the catheter assembly 10C according to the third embodiment, as shown in FIGS. 1 and 9A to 10B, the support member 40A extends long along the axial direction, and the engagement position with the catheter hub 20 can be adjusted. configuration. In addition, in this embodiment, the catheter assembly 10C is configured such that the user directly operates the catheter hub 20 (same configuration as in the first embodiment).

Specifically, the central tube 41 (basal end side tube portion 44) of the support member 40A is formed in a tubular shape extending longer than the axial length of the pair of wings 42, and the total length of the central tube 41 is adjusted. The inner space 45 also extends long in the axial direction. A notch 46 formed in the central tube 41 also extends from the proximal end of the central tube 41 to the vicinity of the distal side tube portion 43 . The pair of wings 42 are connected to the base end side tube portion 44 near the tip end.

A plurality of recesses 48 are formed in the inner peripheral surface of the support member 40A that forms the space 45. As shown in FIG. A pair of recesses 48 are provided at the same position in the axial direction of the central cylinder 41 but with a 180° phase shift. are arranged side by side. The concave portion 48 engages with a convex portion 24 of the catheter hub 20, which will be described later, to form an engagement mechanism 18A that defines the engagement position of the catheter hub 20 with respect to the support member 40A. Each pair of recesses 48 aligned in the axial direction are provided at regular intervals (for example, 1 cm intervals). Hereinafter, the recesses 48 arranged in the axial direction are referred to as a first recess 48a, a second recess 48b, and a third recess 48c in order from the proximal end to the distal end.

The catheter hub 20 inserted into the space 45 of the support member 40A has a pair of protrusions 24 that protrude short radially outward from the outer peripheral surface of the proximal trunk portion 22 . The pair of protrusions 24 are provided at the same position in the axial direction of the catheter hub 20 but at positions 180 degrees out of phase with each other, corresponding to the pair of recesses 48 of the support member 40A. Therefore, when the catheter hub 20 is inserted into the support member 40A, it is possible to engage the pair of protrusions 24 stepwise with the first to third recesses 48a to 48c.

For example, the support member 40A has a length of the catheter 12 protruding from the distal end of the support member 40A in a state in which the pair of projections 24 of the catheter hub 20 are engaged with the pair of first recesses 48a (see the solid line in FIG. 10B). is set to the first length (eg 8 cm). In addition, the support member 40A has the pair of protrusions 24 engaged with the pair of second recesses 48b (see the thick dotted line in FIG. 10B), and the length of the catheter 12 protruding from the tip of the support member 40A is set to the first length. Set a second length (eg, 9 cm) that is longer than the height. Further, the support member 40A is arranged such that the length of the catheter 12 protruding from the tip of the support member 40A is adjusted to the third length with the pair of protrusions 24 engaged with the pair of third recesses 48c (see the thick dashed line in FIG. 10B). Set a third length (eg, 10 cm) that is longer than the second length.

As described above, even when the catheter assembly 10C has the convex portion 24 and the concave portion 48, the two members can be engaged by inserting the catheter hub 20 into the support member 40A. In particular, the support member 40A makes it possible to adjust the length of the catheter 12 in the indwelling state of the indwelling body composed of the catheter 12, the catheter hub 20, and the support member 40A. As a result, the catheter 12 can be inserted into the patient's desired puncture site (for example, a site where the blood vessel can be clearly seen on the skin), and the catheter 12 of an appropriate length can be indwelled in the body according to the patient's body type. can.

Further, the notch 46 of the support member 40A extends from the proximal end of the support member 40A to a position beyond the third recess 48c, so that the support member 40A itself can be elastically deformed appropriately. The elastic deformation allows the catheter hub 20 to move along the axial direction of the support member 40A, and satisfactorily lock the catheter hub 20 at an appropriate position (stepwise). Furthermore, the catheter hub 20 and the support member 40A have marks 25 and 49 on their outer peripheral surfaces, respectively, for confirming the positions at which the pair of projections 24 engage with the pair of first to third recesses 48a to 48c. is preferred. The marks 25 and 49 allow the user to confirm the length by which the catheter 12 protrudes.

10B, the support member 40A is connected to the first to third recesses 48a to 48c and has a guide recess 48d for guiding the projection 24 of the catheter hub 20 in the axial direction. It's okay. The guide recess 48d extends from the base end of the support member 40 and is formed so as to be connected to the upper or lower side of the first to third recesses 48a to 48c. As a result, when the catheter hub 20 is moved in the axial direction of the support member 40A, the projection 24 is positioned in the guide recess 48d to guide the movement. , the catheter hub 20 is slightly rotated at the position where the guide recess 48d and the first to third recesses 48a to 48c are connected, and the protrusion 24 is inserted. As a result, the movement of the projection 24 in the axial direction and the engagement between the projection 24 and the recess 48 can be performed more smoothly.

Further, the engaging mechanism 18A may have a configuration in which the support member 40A is provided with the projections 24 and the catheter hub 20 is provided with the recesses 48 . Furthermore, the catheter assembly 10C may have a configuration in which the catheter operation member 50 is connected to the catheter hub 20 and operated via the catheter operation member 50, as in the second embodiment (see the thin line in FIG. 10B). . For example, the catheter operation member 50 may have a structure that is inserted into the internal space 20a from the proximal end opening 20b of the catheter hub 20. As shown in FIG.

[Fourth embodiment]
In a catheter assembly 10D according to the fourth embodiment, as shown in FIGS. 11, 12A, and 12B, a support member 70 is provided with an arm 71 that can be engaged with the inner needle hub 60, and the arm 71 can be pushed down. It differs from the catheter assemblies 10A to 10C according to the first to third embodiments in that a pressing projection 81 is provided on the catheter hub 80. As shown in FIG.

Specifically, a side wall 61 of the inner needle hub 60 has a slot 62 that communicates with the housing space 60a and that extends from the distal end of the inner needle hub 60 to a predetermined depth. A deep portion of the slot 62 on the base end side is formed with a widened portion 63 in which a positioning projection 72 of the support member 70 to be described later is arranged in the initial state. A wall surface forming the widened portion 63 is formed with an engaged surface 63a on which the engaging surface 72a of the positioning projection 72 is hooked.

A support member 70 accommodated in the inner needle hub 60 is formed in a cylindrical shape without wings 42 , and has an arm 71 (hook portion) engageable with the inner needle hub 60 on the outer peripheral surface of the support member 70 . In a plan view, the arm 71 projects short radially outward from the outer peripheral surface, bends at a bending point, and extends in the proximal direction. The arm 71 initially fits in the proximal portion of the slot 62 of the inner needle hub 60 .

A portion of the arm 71 extending in the proximal direction is formed in a flat plate shape having a certain width. A positioning protrusion 72 that can be hooked on the side wall 61 of the inner needle hub 60 in a plan view is provided on the projecting end portion of the arm 71 on the base end side. The positioning projection 72 is set to have a width of a predetermined ratio (for example, 1/2) with respect to the overall width of the arm 71 and is provided on the outer side of the arm 71 in the width direction. Further, the positioning projection 72 is formed in a triangular shape having an engaging surface 72a orthogonal to the plane of the arm 71 when viewed from the side.

Further, the support member 70 has guide cutouts 73 on its outer peripheral surface at a position facing the arm 71 . The guide notch 73 communicates with a space 74 in the support member 70 and extends linearly from the base end of the support member 70 to the base end of the connecting portion of the arm 71 .

On the other hand, the catheter hub 80 has pressing projections 81 projecting radially outward from the outer peripheral surface. The engagement mechanism 18 that engages the support member 70 and the catheter hub 80 has a structure that engages the inner peripheral surface of the support member 70 and the outer peripheral surface of the catheter hub 80, as in the first embodiment. ing.

The pressing projection 81 is formed in a right-angled triangular shape, in a side view, having a top portion 81a on the distal end side, an oblique side 81b inclined downward from the top portion 81a in the base end direction and downward, and a bottom top portion 81c. The pressing protrusion 81 is formed to have a protrusion length that protrudes from the guide notch 73 of the support member 70 but does not reach the positioning protrusion 72 of the arm 71 when the catheter hub 80 is inserted into the support member 70 . ing. Therefore, when the guide notch 73 is moved in the distal direction, the oblique side 81b of the pressing projection 81 comes into contact with the arm 71 and presses the arm 71 downward.

The catheter assembly 10D according to the fourth embodiment is basically configured as described above. In the initial state of the catheter assembly 10D, the arm 71 of the support member 70 is accommodated in the slot 62 of the distal end portion 64 of the inner needle hub 60, and the engaging surface 72a of the positioning protrusion 72 is engaged with the inner needle hub 60. It is hooked on the mating surface 63a. Therefore, the support member 70 is restricted from axially moving and circumferentially rotating with respect to the inner needle hub 60 , and is prevented from coming off the inner needle hub 60 . Further, the catheter hub 80 is arranged inside the inner needle hub 60 on the proximal end side of the support member 70 .

When using this catheter assembly 10D, the user advances the catheter hub 80 in the distal direction while the double structure needle 16 is pierced. At the time of advance, the insertion support hole 70a formed inside the distal end side of the support member 70 suppresses the bending of the inner needle 14 and allows the catheter 12 to slide. Further, the support member 70 is inserted into the space 74 through the base end opening 70b when the catheter hub 80 is advanced.

As shown in FIGS. 13A and 13B , when the catheter hub 80 is advanced into the support member 70 to some extent, the pushing protrusion 81 of the catheter hub 80 enters the guide notch 73 and moves toward the distal end along the guide notch 73 . Moving. The pressing projection 81 brings the oblique side 81 b into contact with the proximal end of the arm 71 (the location adjacent to the positioning projection 72 ) while the guide notch 73 is moving. As a result, the base end (positioning projection 72) of arm 71 is gradually pushed downward, but until catheter hub 80 is fitted to support member 70 to some extent, engaging surface 72a and engaged surface are separated from each other. The engagement of 63a continues.

As shown in FIGS. 14A and 14B, when the catheter hub 80 and the support member 70 are fitted together, the lower apex 81c of the pressing projection 81 pushes down the arm 71, thereby disengaging the engaging surface 72a and the engaged surface 63a. is released just (or by slightly advancing the catheter hub 80 relative to the support member 70). This allows the support member 70 to move relative to the inner needle hub 60 . That is, the arm 71 becomes movable within the slot 62 , and the catheter hub 80 and the support member 70 move together in the distal direction and are separated from the inner needle hub 60 .

As described above, in the catheter assembly 10D according to the fourth embodiment, the inner needle hub 60 and the support member 70 are firmly engaged with each other, thereby preventing the support member 70 from coming off and preventing the support member 70 from coming off. Engagement with the moved catheter hub 80 can be facilitated. By releasing the engagement between the support member 70 and the inner needle hub 60 during or after the engagement between the catheter hub 80 and the support member 70, the catheter hub 80 and the support member 70 are well integrated and separated. It is possible to

The catheter assembly 10D may have a plurality of arms 71 of the support member 70. In this case, the number of slots 62 of the inner needle hub 60 and the pressing protrusions 81 of the catheter hub 80 correspond to the number of arms 71. It should be provided.

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made along the gist of the invention. For example, the catheter assemblies 10A-10D may include safety mechanisms to prevent accidental puncture of the inner needle 14 after removal of the catheter hubs 20, 80, and to guide intravascular movement of the catheter 12. A guide wire and a mechanism for inserting the guide wire may be provided.

Claims (9)

a catheter;
a catheter hub fixedly holding the catheter;
an inner needle releasably inserted into the catheter;
a catheter assembly comprising an inner needle hub fixedly holding the inner needle and having a distal end,
A support member that suppresses bending of the inner needle while allowing the catheter to slide is disposed at the distal end of the inner needle hub,
The support member is integrally separated from the inner needle hub as the catheter hub moves ,
the catheter hub and the support member have an engagement mechanism that engages the catheter hub and the support member when the catheter hub moves to the distal end;
The support member is configured to be integrated by accommodating a portion of the catheter hub inside from the proximal end,
The engagement mechanism is a structure that engages the outer peripheral surface of the catheter hub and the inner peripheral surface of the support member.
A catheter assembly characterized by: a catheter;
a catheter hub fixedly holding the catheter;
an inner needle releasably inserted into the catheter;
a catheter assembly comprising an inner needle hub fixedly holding the inner needle and having a distal end,
A support member that suppresses bending of the inner needle while allowing the catheter to slide is disposed at the distal end of the inner needle hub,
The support member is integrally separated from the inner needle hub as the catheter hub moves,
the catheter hub and the support member have an engagement mechanism that engages the catheter hub and the support member when the catheter hub moves to the distal end;
The support member is configured to be integrated by accommodating a portion of the catheter hub inside from the proximal end,
A catheter according to claim 1, wherein the engagement mechanism has a structure in which a convex portion provided on one of the outer peripheral surface of the catheter hub and the inner peripheral surface of the support member is inserted into a concave portion provided on the other. assembly. A catheter assembly according to claim 2 , wherein
A catheter assembly, wherein the engagement mechanism is capable of engaging the catheter hub at a plurality of axial positions of the support member. In the catheter assembly according to any one of claims 1 to 3 ,
A catheter assembly, wherein the support member has a notch extending a predetermined length from the proximal end in the axial direction. In the catheter assembly according to any one of claims 1 to 4 ,
A catheter assembly comprising a catheter operating member for operating movement of the catheter and the catheter hub. In the catheter assembly according to any one of claims 1 to 5 ,
A catheter assembly, wherein the support member has a portion that releasably engages with the inner needle hub. A catheter assembly according to claim 6 , wherein
A catheter assembly, wherein the portion that releasably engages the inner needle hub includes a pair of wings. A catheter assembly according to claim 6 , wherein
The portion detachably engaged with the inner needle hub includes a hook portion that hooks on the inner needle hub in an initial state before the inner needle is punctured,
The catheter assembly, wherein the hooking portion releases the hooking with the inner needle hub in conjunction with movement of the catheter hub. In the catheter assembly according to any one of claims 6 to 8 ,
the inner needle hub has a slot extending from a predetermined position in the axial direction of the inner needle hub to a distal end;
A catheter assembly, wherein a portion of the support member is inserted into the slot to guide movement of the support member.

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