JP7134410B2 - Indwelling needle and indwelling needle assembly - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indwelling needle and an indwelling needle assembly including the indwelling needle used for transfusion, blood collection, hemodialysis, and the like.

Conventionally, a connection hub is provided on the base end side of a hollow needle that is percutaneously inserted into a blood vessel, and the internal flow path from the hollow needle to the connection hub can be connected to the external flow path at the connection hub. Indwelling needles are known. Such an indwelling needle is often provided to medical sites as an indwelling needle assembly in combination with an inner needle having an inner needle hub on the proximal side of an inner needle main body for puncture.

Such an indwelling needle or the like is fixed to the arm or the like by taping or the like after piercing a blood vessel such as the patient's arm when, for example, performing infusion, blood collection, or hemodialysis, and is attached to the connection hub to the external flow channel. It will be used for treatment by connecting a syringe or a tube that leads to a blood circuit for dialysis.

By the way, such an indwelling needle or the like is required to be stably held by taping or the like in a state in which the needle body is pierced into the human body, and to be stably connected to an external flow path.

However, conventional indwelling needles are provided with a needle hub made of hard resin on the proximal end side of the hollow needle, as described in, for example, Japanese Patent Application Laid-Open No. 2002-126090 (Patent Document 1). A connection hub made of a hard material is provided integrally with the needle hub. With such an indwelling needle having a conventional structure, it was difficult to fix the needle hub to the human body by taping because the connecting hub interferes with the fixing location and is narrow. Moreover, when attaching or detaching the external channel to or from the connection hub while the needle hub is fixed to the human body by taping, it is difficult to attach or detach the external channel because the area where the needle hub can be gripped is narrow.

It is conceivable to fix the external channel connected to the connection hub by taping it to the human body, but it is difficult to obtain sufficient holding stability compared to fixing the indwelling needle itself. Moreover, since the large-diameter needle hub and connection hub are positioned between the hollow needle punctured into the human body and the external channel fixed by taping, the needle hub and connection hub are pressed against the human body causing pain. In addition to this, there is also a risk that the hollow needle will be pulled in the direction of withdrawal by the action of the lever with the large-diameter needle hub or connecting hub serving as a fulcrum.

In addition, as described in Japanese Patent Application Laid-Open No. 2003-199822 (Patent Document 2), the needle hub of the hollow needle (catheter 4) and the connecting hub (catheter hub 2) are clamped by a flexible tube. There has also been proposed an indwelling needle that has a structure connected by a tube (3) and that can be operated to prevent backflow of blood by clamping the clamping tube. Here, the needle hub of the hollow needle in Patent Document 2 is a portion to which the base end of the hollow needle (catheter 4) is fixed and inserted into the tip portion of the clamping tube (3).

However, in an indwelling needle provided with such a clamping tube, the distal end of the clamping tube is further externally fixed to a hard, large-diameter needle hub provided on the proximal end side of the hollow needle. , there is a problem that the structure is complicated and the manufacturing is troublesome. Therefore, when it is fixed to the human body by taping, the hard needle hub to which the clamping tube is externally inserted and fixed is pressed against the human body, which tends to cause great pain.

JP-A-2002-126090 Japanese Patent Application Laid-Open No. 2003-199822

The present invention has been made against the background of the above-mentioned circumstances, and the problem to be solved is to be able to easily fix the hollow needle to the human body by taping or the like in a state of being punctured by the hollow needle, and to reduce the patient's pain. To provide an indwelling needle and an indwelling needle assembly with a new structure that can be obtained.

Hereinafter, aspects of the present invention that have been made to solve such problems will be described. It should be noted that the constituent elements employed in each aspect described below can be employed in any possible combination.

A first aspect of the present invention comprises a hollow needle that is percutaneously inserted into a blood vessel, a needle hub in which the hollow needle is fixed, a connection hub that is connected to an external flow path, and the needle hub. The needle hub is formed by the distal end portion of the elastic tube, and the elastic tube and the needle hub are formed as a single component. The hollow needle comprises an exposed portion not covered with the elastic tube and a fixed portion covered with the elastic tube, and the fixed portion of the hollow needle extends outwardly from the exposed portion at the proximal end. The indwelling needle is characterized by having a first raised portion with a large diameter .

According to the indwelling needle constructed according to this mode, the hollow needle punctured into the human body and the connection hub connected to the external flow path are connected by a bendable elastic tube. Even when taped on the end side or the external flow path, the elastic tube bends and deforms so as to follow the patient's body surface, making it easier to fix with taping and lessening the burden on the patient. The force acting in the withdrawal direction can also be reduced.

In addition, like the indwelling needle of Patent Document 2, the distal end of an elastic tube (clamping tube) may be externally inserted and fixed to a hard, large-diameter needle hub provided on the proximal end side of the hollow needle. The structure can be simplified because there is no

The method of fixing the hollow needle and the elastic tube is not limited to adhesion or welding, but it is preferable to use the fitting force of the elasticity of the elastic tube to the outer peripheral surface of the hollow needle. As a result, the fluid tightness (sealing property) at the connecting portion between the hollow needle and the elastic tube can be improved, and the manufacturing can be facilitated. Further, a plurality of such elastic fitting methods and fixing methods such as adhesion and welding may be combined and adopted.

Furthermore, as the hollow needle in this embodiment, it is possible to employ not only soft synthetic resin needles but also hard metal needles such as stainless steel. When a hollow needle made of synthetic resin, which is less rigid than metal, is used, the elastic tube inserted around the proximal end portion of the hollow needle can be more easily deformed, which is preferable. In addition, according to the indwelling needle constructed according to this aspect, it is possible to exhibit an anchoring effect based on a mechanical locking action on the elastic tube, and the fixing force of the elastic tube to the hollow needle can be effectively increased. can demonstrate.

According to a second aspect of the present invention, in the indwelling needle according to the first aspect, the hardness of the material of the needle hub is Shore D49 or less when the hollow needle is not fixed.

According to the indwelling needle constructed according to this mode, since the material of the needle hub is provided with hardness equal to or less than a predetermined hardness, even when the needle hub is pressed against the skin, it is possible to reduce pain.

A third aspect of the present invention is the indwelling needle according to the first or second aspect, wherein the fixing portion is press-fitted into the needle hub.

According to the indwelling needle constructed according to this mode, unlike the conventional art, it is not necessary to fix the hollow needle to the needle hub with a crimp pin or the like, so the structure and manufacturing are easy.

In addition, since the elastic tube is directly connected to the proximal end of the hollow needle, there is no need to provide a separate hard hub at the proximal end of the hollow needle, effectively maintaining the elastic properties of the elastic tube. Therefore, it is possible to reduce the pain when it is pressed against the patient's body by taping or the like.

Furthermore, since the elastic tube is directly connected to the proximal end portion of the hollow needle, there is no need to provide a separate hard hub or the like at the proximal end portion of the hollow needle. Compared to a structure in which an elastic tube is externally inserted around the needle hub, the connecting portion between the hollow needle and the elastic tube can be prevented from increasing in diameter, and the pressure applied to the patient's body by taping or the like can be reduced.

A fourth aspect of the present invention is the indwelling needle according to any one of the first to third aspects, wherein the hollow needle has the first protrusion on the distal side of the first protrusion. a second raised portion having an outer diameter smaller than that of the exposed portion and an outer diameter larger than that of the exposed portion; and an annular recess is formed between the first raised portion and the second raised portion. There is.

According to the indwelling needle constructed according to this aspect, the annular recess between the first protruding portion and the second protruding portion can exhibit an anchoring effect based on a mechanical locking action on the elastic tube. , and the fixing force of the elastic tube to the hollow needle can be effectively exerted.

In particular, the elastic tube is covered up to the tip side of the maximum outer diameter portion (first raised portion) of the hollow needle, and the wall thickness of the elastic tube is the smallest at the maximum outer diameter portion of the hollow needle. , and the thickness is larger on the tip side than there. By providing such a thin portion and a thick portion on the distal end side, the anchor effect of the fixing portion of the hollow needle with respect to the elastic tube can be exhibited more effectively, and a large withdrawal resistance can be set.

A fifth aspect of the present invention is the indwelling needle according to the fourth aspect, wherein the outer peripheral surface of the distal end portion of the needle hub has an R surface shape that gradually increases in diameter toward the proximal end side. , the outer diameter of the tip portion of the R surface is larger than the outer diameter of the second raised portion of the hollow needle.

According to the indwelling needle constructed according to this aspect, the boundary between the second raised portion and the needle hub is less likely to be pressed against the skin, and the R surface provided at the distal end of the soft needle hub is pressed against the patient's skin. Since it is easy to wear, it is possible to reduce the pain when it is pressed against the patient's body by taping or the like.

A sixth aspect of the present invention is the indwelling needle according to any one of the first to fifth aspects, wherein the proximal end of the fixing portion of the hollow needle is positioned further proximal than the proximal end of the needle hub. It is located on the side.

According to the indwelling needle constructed according to this aspect, even when the connection hub is pressed against the skin and taping is performed, the punctured hollow needle is less likely to be pulled out in the direction of being pulled out by the action of the lever.

A seventh aspect of the present invention is the indwelling needle according to any one of the first to sixth aspects, wherein the outer peripheral surface of the proximal end portion of the exposed portion of the hollow needle gradually becomes It has a tapered surface shape with a small diameter.

According to the indwelling needle constructed according to this mode, compared with the case where the proximal end portion of the exposed portion has a square shape, pain when pressed against the patient's body by taping or the like can be reduced.

An eighth aspect of the present invention is the indwelling needle according to the seventh aspect, wherein the proximal end portion of the exposed portion of the hollow needle having the tapered outer peripheral surface includes a A plurality of concave grooves extending in the length direction are provided in the circumferential direction, whereby the base end portion has an outer peripheral structure having a plurality of rib-like projections whose height dimension changes in the length direction of the hollow needle. It is said that

According to the indwelling needle constructed according to this aspect, at the proximal end of the hollow needle where stress is likely to concentrate during use, the plurality of rib-like projections extending in the longitudinal direction are raised toward the distal end of the hollow needle. It is integrally formed with a shape whose width gradually decreases. Therefore, by avoiding a sudden change in rigidity at the base end portion of the hollow needle and dispersing the stress in the longitudinal direction of the hollow needle, the durability and strength resistance can be improved. Moreover, since the grooves extending in the length direction provided between the rib-shaped projections in the circumferential direction also exhibit the effect of stealing thickness during molding, there is also a technical effect of avoiding resin molding defects such as sink marks and voids. can be achieved.

A ninth aspect of the present invention is the indwelling needle according to any one of the first to eighth aspects, wherein the internal channel extending from the hollow needle to the connection hub and connected to the external channel has A hemostatic valve is provided.

According to the indwelling needle constructed according to this aspect, the adoption of the hemostatic valve eliminates the need to clamp the elastic tube to stop bleeding, thereby ensuring a large degree of freedom in designing the material and characteristics of the elastic tube. For example, it becomes possible to realize an elastic tube that can further alleviate the patient's pain.

A tenth aspect of the present invention is the indwelling needle according to the ninth aspect, wherein the hemostasis valve is provided inside the connection hub in the internal flow path, and a proximal end of the hemostasis valve A sleeve-shaped pusher is arranged movably in the direction of the flow path, and when the pusher moves toward the hemostatic valve, the hemostatic valve is pushed open and communicated. There is.

According to the indwelling needle constructed according to this mode, the pusher moves even when the external channel is connected to the connection hub, and the valve body is brought into communication. can be made as small as the length of the pusher to facilitate connection and disconnection of the external flow path.

An eleventh aspect of the present invention is the indwelling needle according to the tenth aspect, wherein the elastic tube is provided on the distal side of the hemostasis valve, and the proximal end of the elastic tube extends toward the connection hub. The inner diameter dimension increases toward the .

According to the indwelling needle constructed according to this aspect, the inner diameter of the proximal end portion of the elastic tube is large, so that the hemostatic valve functions as a space for pushing open, and the hemostatic valve can be easily pushed open.

A twelfth aspect of the present invention is the indwelling needle according to any one of the first to eleventh aspects, wherein the outer diameter dimension of the elastic tube is smaller than the outer diameter dimension of the connection hub. be.

According to the indwelling needle constructed according to this mode, the connection hub can be grasped and the elastic tube can be moved at the time of indwelling, which facilitates handling.

A thirteenth aspect of the present invention is the indwelling needle according to any one of the first to twelfth aspects, comprising a cover member that covers the needle hub or the elastic tube.

According to the indwelling needle constructed according to this aspect, the resistance to external forces and the blood pressure of blood flowing through the internal channel is increased.

A fourteenth aspect of the present invention is the indwelling needle according to any one of the first to thirteenth aspects, wherein an inner needle hub is provided on the proximal end side of the inner needle main body that is inserted through the hollow needle. An indwelling needle assembly combined with an inner needle.

According to the indwelling needle assembly constructed according to this aspect, the indwelling needle according to any one of the first to fourteenth aspects is used as the outer needle, and the inner needle is combined with the outer needle to obtain the above-described effects. It becomes possible to provide an indwelling needle assembly capable of exerting In particular, by adopting an inner needle main body made of a hard material, it becomes possible to pierce the skin with a soft hollow needle and indwell it in a patient's blood vessel.

A fifteenth aspect of the present invention is the indwelling needle assembly according to the fourteenth aspect, wherein the inner diameter dimension of a portion of the elastic tube through which the inner needle body is inserted is inserted into the inner needle hub. It has a portion that is approximately equal to the outer diameter of the inner needle body.

According to the indwelling needle assembly constructed according to this aspect, the amount of air entering the human body can be minimized.

According to the indwelling needle and the indwelling needle assembly constructed according to the present invention, the hollow needle and the connection hub are connected by an elastically deformable elastic tube. Can be easily fixed. In addition, the patient's pain can be advantageously reduced because the rigid member is not pressed against the patient's skin.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which shows the whole indwelling needle as the 1st Embodiment of this invention. FIG. 2 is a plan view of the indwelling needle shown in FIG. 1; (a) is a longitudinal cross-sectional view of the indwelling needle shown in FIG. 1, and (b) is a diagram showing an enlarged main part of (a). FIG. 4 is a longitudinal sectional view showing an enlarged main part in FIG. 3 ; The perspective view which shows the whole indwelling needle assembly comprised including the indwelling needle shown by FIG. FIG. 6 is a plan view of the indwelling needle assembly shown in FIG. 5; FIG. 6 is a longitudinal sectional view of the indwelling needle assembly shown in FIG. 5; FIG. 8 is a longitudinal sectional view showing an enlarged main part in FIG. 7 ; FIG. 2 is an enlarged longitudinal sectional view showing a state in which an external channel is connected to the indwelling needle shown in FIG. 1; The top view which expands and shows the indwelling needle as the 2nd Embodiment of this invention. FIG. 11 is a longitudinal sectional view of the indwelling needle shown in FIG. 10; FIG. 11 is a plan view showing a hollow needle that constitutes the indwelling needle shown in FIG. 10; FIG. 13 is a longitudinal sectional view of the hollow needle shown in FIG. 12; FIG. 4 is a longitudinal sectional view showing an enlarged main part of an indwelling needle as another aspect of the present invention. FIG. 4 is a longitudinal sectional view showing an indwelling needle as still another aspect of the present invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First, FIGS. 1 to 4 show an outer needle 10 as a first embodiment of an indwelling needle according to the present invention. The outer needle 10 includes an outer needle main body 12 as a hollow needle and a needle hub 13 to which the outer needle main body 12 is fixed on the distal end side, and a connection hub 14 connected to the external flow path on the proximal end side. The needle hub 13 and connection hub 14 are connected by a bendable elastic tube 16 . As shown in FIGS. 5 to 8, the outer needle 10 is configured as an indwelling needle assembly 20 by inserting the inner needle 18. After the indwelling needle assembly 20 is punctured into the patient's skin, By pulling out the inner needle 18 from the outer needle 10, the outer needle main body 12 of the outer needle 10 is percutaneously inserted into the patient's blood vessel and left there. In the following description, the length direction and needle axis direction refer to the horizontal direction in FIG. 2 along which the outer needle 10 extends. Further, the distal side refers to the left side in FIG. 2, which is the side on which the patient is punctured, while the proximal side refers to the right side in FIG. 2, which is the side to be gripped by the user.

More specifically, the outer needle body 12 has a substantially hollow needle shape as a whole and is flexible. A connecting portion 22 having a deformed outer peripheral surface is integrally formed at the base end portion of the outer needle main body 12, and the outer diameter of the connecting portion 22 is is made larger than

In addition, a fixed groove 24 as an annular recess that opens to the outer peripheral side and extends over the entire circumference is provided in an axially intermediate portion of the connecting portion 22, that is, the portion where the fixed groove 24 is provided. , the outer diameter dimension of the connecting portion 22 is reduced. In other words, first and second protuberances 26a and 26b having outer diameters larger than the bottom wall of the fixed recessed groove 24 extend over the entire periphery on the distal end side and the proximal end side of the fixed recessed groove 24. The outer diameter of the outer needle main body 12 is the largest at the first raised portion 26a on the proximal end side.

Furthermore, the proximal side end surface of the connecting portion 22 is formed by the proximal side end surface of the first raised portion 26a, and is a reverse tapered surface 27a whose outer diameter gradually decreases toward the proximal side. . On the other hand, the tip side end face of the connecting portion 22 is formed by the tip side end face of the second raised portion 26b, and is a tapered surface 27b whose outer diameter gradually decreases toward the tip side.

On the other hand, the distal end portion of the outer needle main body 12 is provided with a tapered outer peripheral surface 28 having a gradually smaller outer diameter. Further, a plurality of through holes 30 are provided in the distal end portion of the outer needle main body 12 to improve the flow efficiency of fluid to the outer needle main body 12 .

The outer needle main body 12 can be made of various soft resins such as ethylene-tetrafluoroethylene copolymer (ETFE), polyurethane, polyether nylon resin, polypropylene, and polyethylene elastomer by various known manufacturing methods. .

Furthermore, the connection hub 14 has a generally cylindrical shape as a whole and is made of a hard synthetic resin. That is, an intermediate wall portion 32 that protrudes in the direction perpendicular to the axis from the inner peripheral surface of the connection hub 14 and spreads in an annular shape is provided inside the connection hub 14 at the intermediate portion in the length direction. A tubular fixed tubular portion 34 extends from the peripheral portion to the tip side. On the other hand, from the outer peripheral edge portion of the proximal end face of the intermediate wall portion 32 , a housing cylinder portion 36 with approximately the same outer diameter as the fixed cylinder portion 34 extends toward the proximal end side. Further, in the center of the intermediate wall portion 32, an insertion hole 38 through which the inner needle 18 is inserted is formed with an inner diameter dimension larger than the outer diameter dimension of large diameter portions 84, 84 of an inner needle main body 78, which will be described later. . Furthermore, a male screw 41 is provided on the outer peripheral surface of the base end side opening 40 of the housing tube portion 36 . This allows an external flow path 124 such as a luer lock syringe to be connected to the proximal opening 40 of the connection hub 14, as will be described later.

Here, in the connection hub 14 , the hemostasis valve mechanism 42 is accommodated inside the tubular accommodation portion 36 . That is, on the base end side of the intermediate wall portion 32, an elastic valve body 43 as a substantially disc-shaped hemostatic valve made of rubber or elastomer is disposed in contact with the intermediate wall portion 32. A body 43 is formed with a substantially constant thickness dimension.

In this embodiment, the central portion of the elastic valve body 43 is used as the valve body portion 44, and slits 45 extending from the center in three directions at equal intervals (every 120°) are formed therethrough. The shape of the slit is not particularly limited, and may be a straight line shape, a cross shape, or a radial shape extending in a plurality of directions from the center. The slit 45 of the elastic valve body 43 is in a closed state when an external operating force is not applied to the elastic valve body 43, and the distal end side and the proximal end side of the elastic valve body 43 are in a non-communication state. It is said that A cylindrical holding portion 46 protruding toward the base end is integrally formed on the outer peripheral edge portion of the elastic valve body 43 . Further, the holding portion 46 has a tapered inner peripheral surface 47 whose inner diameter gradually increases toward the proximal end. Furthermore, a concave groove 48 extending in the circumferential direction on the inner peripheral surface of the holding portion 46 is formed in the proximal end surface of the elastic valve body 43 . The recessed groove 48 relatively easily permits elastic deformation for opening the slit 45 when a pusher 50 (to be described later) is pushed in, thereby improving durability due to stress relaxation.

A sleeve-shaped pusher 50 having an inner hole 49 is disposed on the base end side of the elastic valve body 43, and a substantially cylindrical pusher guide 51 is accommodated on the outer peripheral side of the pusher 50. It is fixedly attached to the inner peripheral surface of the cylindrical portion 36 by means of concave-convex fitting. The inner peripheral surface of this pusher guide 51 is a guide surface 52 extending in the direction of the needle shaft with a substantially constant inner diameter.

At the proximal end portion of the pusher guide 51, a cylindrical retaining portion 53 is provided which protrudes toward the inner periphery by making the inner diameter slightly smaller. On the other hand, a pusher projection 54 having a gradually reduced outer diameter is integrally formed at the tip of the pusher guide 51 . The pressing protrusion 54 is fitted in the holding portion 46 of the elastic valve body 43 so that the tapered inner peripheral surface 47 and the outer peripheral surface of the pressing protrusion 54 overlap each other, and the tip of the pressing protrusion 54 is attached to the elastic valve body. It enters into the concave groove 48 on the proximal end surface of 43 . As a result, the holding portion 46 of the elastic valve body 43 is fluid-tightly sandwiched between the housing cylinder portion 36 and the pusher guide 51 in the direction perpendicular to the needle axis, and the outer peripheral portion of the elastic valve body 43 is held by the needle. It is sandwiched between the intermediate wall portion 32 and the pusher guide 51 in the axial direction.

Further, the distal end portion of the pusher 50 is provided with a penetrating portion 55 of a tapered outer peripheral surface whose outer diameter gradually decreases toward the distal end side. A stepped portion 56 protruding on the outer peripheral surface is formed at the intermediate portion in the direction. By locking the stepped portion 56 to the retaining portion 53 of the pusher guide 51 , the tip portion of the pusher 50 is prevented from coming out of the pusher guide 51 and assembled. Note that the tip of the pusher 50 is axially opposed to a portion of the proximal end surface of the valve main body 44 that is closer to the inner peripheral side than the groove 48 . The distal end and the proximal end surface of the valve body portion 44 are in contact with each other. On the other hand, the base end side of the stepped portion 56 of the pusher 50 extends in a substantially straight cylindrical shape.

In the insertion portion 55 of the pusher 50 having such a shape, the outer peripheral surface of the base end portion where the outer diameter is the largest is in sliding contact with the guide surface 52 of the pusher guide 51, and is closer to the base end than the stepped portion 56 of the pusher 50. is in sliding contact with the cylindrical inner peripheral surface of the retaining portion 53 of the pusher guide 51, the pusher 50 is guided by the pusher guide 51 in the direction of the needle axis (the direction of the flow path of the internal flow path 60, which will be described later). ) can be moved relative to each other.

When the pusher 50 is moved toward the distal end side in the axial direction by an operating force applied from the outside and pressed against the elastic valve body 43, the slit 45 of the valve body 44 is pushed open to be in a communicating state. It's becoming On the other hand, when the operating force is released, the pusher 50 is also pushed back to the initial position on the base end side by the restoring action of the elastic force of the elastic valve body 43, and the slit 45 is automatically restored to the closed shut-off state. It is designed to be obtained.

The outer needle main body 12 and the connection hub 14 constructed as described above are connected by an elastic tube 16 . That is, the distal end portion of the elastic tube 16 is directly fixed to the proximal end portion (connecting portion) 22 of the outer needle main body 12, and the proximal end portion 58 of the elastic tube 16 is inserted into the fixed cylindrical portion 34 of the connection hub 14. It is fixed by gluing, welding, or the like. As a result, the inner hole of the outer needle main body 12, the inner hole of the elastic tube 16, and the inner hole of the connection hub 14 (specifically, the inner hole 49 of the pusher 50) communicate with each other. Thus, the internal flow path 60 of the outer needle 10 is configured to extend in the horizontal direction in FIG. Further, in this embodiment, the distal end portion of the elastic tube 16 constitutes the needle hub 13 that supports the outer needle main body 12 . In other words, the needle hub 13 to which the hollow needle (outer needle main body) 12 is fixed and the elastic tube 16 connecting the needle hub 13 and the connection hub 14 are integrally formed.

The elastic tube 16 has a generally cylindrical shape as a whole, and is made of a soft synthetic resin so that it can be easily elastically deformed. In addition, the outer peripheral surface of the distal end portion 13 of the elastic tube 16 is formed as a tapered surface 62 in which the outer diameter dimension gradually decreases toward the distal end side. In particular, as shown in FIG. 3B, the tip of the tapered surface 62 is an R surface 62a having a substantially constant curvature, and the minimum outer diameter dimension of the R surface 62a is the same as that of the outer needle main body 12. 2 is slightly larger than the maximum outer diameter dimension of the raised portion 26b. That is, the radial width dimension of the distal end portion 13 of the elastic tube 16 (the distal end side thick wall portion 68 described later) is slightly larger than the groove depth dimension of the fixed groove 24, and the distal end side thick wall portion 68 is fixed. The distal end side thick portion 68 protrudes from the fixed groove 24 when it is fitted into the groove 24 .

The distal end portion (needle hub 13 ) of the elastic tube 16 is directly covered and fixed to the connecting portion 22 , which is the proximal end portion of the outer needle main body 12 . Specifically, the connecting portion 22 is covered with the elastic tube 16 on the proximal end side of the second raised portion 26b. Therefore, in the outer needle main body 12, the exposed portion 63a that is not covered with the elastic tube 16 is formed on the distal end side of the second raised portion 26b, while the fixed portion 63b that is covered with the elastic tube 16 is located at the second end. is configured on the proximal end side of the raised portion 26b. Here, in the single-piece state of the elastic tube 16 before the elastic tube 16 is fixed to the outer needle body 12, the inner diameter dimension at the distal end portion 13 of the elastic tube 16 is When the fixing portion 63b of the outer needle main body 12 is press-fitted into the distal end portion 13 of the elastic tube 16, the distal end portion 13 of the elastic tube 16 expands and deforms to the outer peripheral side, The elastic tube 16 is fixed to the outer needle main body 12 in close contact.

That is, in the distal end portion 13 of the elastic tube 16, the portion positioned on the outer peripheral side of the first raised portion 26a of the connecting portion 22 bulges out to the outermost side to form a maximum outer diameter portion 64 having the largest outer diameter dimension. In addition, the peripheral wall of the portion is pulled toward the outer peripheral side by the first raised portion 26a, thereby forming a thin portion 66 whose thickness dimension is locally reduced. As a result, portions on the distal side and proximal side of the thin portion 66 are formed into a distal side thick portion 68 and a proximal side thick portion 70 having a thickness dimension larger than that of the thin portion 66 . In other words, the distal thick portion 68 of the elastic tube 16 is fitted into the fixing recessed groove 24 of the connecting portion 22, and the substantial needle hub 13 is constituted by the distal thick portion 68 and fixed. The proximal end of the portion 63b (the first raised portion 26a) is located closer to the proximal side than the proximal end of the needle hub 13 (the distal thick portion 68). The base end surface (reverse tapered surface 27a) of the fixing portion 63b is positioned closer to the base end than the position (maximum outer diameter portion 64) where the outer diameter dimension of the needle hub 13 is maximum.

Further, the distal end portion 13 of the elastic tube 16 is bulging and deformed based on the first raised portion 26a of the outer needle main body 12 to form a maximum outer diameter portion 64. The maximum outer diameter portion 64 is formed by the elastic tube. It has an outer diameter larger than that of the longitudinal intermediate portion 72 of 16 . That is, the outer peripheral surface of the distal end portion 13 of the elastic tube 16 includes a tapered surface 62 in which the outer diameter dimension gradually increases from the distal end toward the maximum outer diameter portion 64, and an intermediate portion in the longitudinal direction of the elastic tube 16 from the maximum outer diameter portion 64. It has a reverse tapered surface 74 whose outer diameter gradually decreases toward 72 . Therefore, the distal end portion 13 and the intermediate portion 72 of the elastic tube 16 are connected with an outer surface shape (reverse tapered surface 74) that is smoothly curved in the longitudinal direction. In addition, when the fixing portion 63b of the outer needle body 12 is press-fitted into the elastic tube 16, the outer diameter dimension of the maximum outer diameter portion 64 is smaller than the outer diameter dimension of the connection hub 14, and the elastic tube 16 is The diameter is smaller than that of the connection hub 14 throughout.

Here, the reverse tapered surface 74 provided on the distal end portion 13 of the elastic tube 16 is formed corresponding to the reverse tapered surface 27a provided on the outer peripheral surface of the first raised portion 26a of the outer needle main body 12. Therefore, the taper angles of the respective reverse tapered surfaces 74 and 27a are substantially equal. In addition, since the distal end portion 13 of the elastic tube 16 is covered from the outside on the fixed portion 63b of the outer needle main body 12, the outer diameter dimension of the distal end portion 13 of the elastic tube 16 is larger than the outer diameter dimension of the lengthwise intermediate portion 72. However, in a single-piece state in which the elastic tube 16 is not fixed to the outer needle main body 12, the outer diameter dimension of the longitudinal intermediate portion 72 may be larger than the outer diameter dimension of the tip portion 13, for example. .

In the present embodiment, the proximal end portion (fixed portion) 63b of the outer needle main body 12 is press-fitted into the distal end portion 13 of the elastic tube 16, thereby forming a distal thick portion 68 that is fitted into the fixed recessed groove 24. An annular gap 73 is formed between it and the first raised portion 26a. With this configuration, when the elastic tube 16 is attached to the patient's skin, the elastic tube 16 becomes flexible with respect to the load during attachment.

Furthermore, at the proximal side opening of the proximal portion 58 of the elastic tube 16 inserted into the connection hub 14, a tapered surface 75 is provided on the inner peripheral surface, the inner diameter dimension of which gradually increases toward the proximal side. .

The elastic tube 16 having such a structure is made of various known soft resins such as polyvinyl chloride, ethylene-tetrafluoroethylene copolymer (ETFE), polyurethane, polyether nylon resin, polypropylene, and polyethylene elastomer. It can be configured by manufacturing method. This may facilitate manufacturing of the elastic tube 16 .

Here, since the distal end portion 13 of the elastic tube 16 is externally inserted into the fixing portion 63b of the outer needle main body 12, the wall thickness dimension (needle hub) of the distal end portion 13 (needle hub) of the elastic tube 16 The sum of the wall thickness dimension of the elastic tube 16 and the wall thickness dimension of the outer needle main body 12) is larger than the wall thickness dimension of the elastic tube 16 at the longitudinal intermediate portion 72 thereof. Therefore, in the connected state of the elastic tube 16 and the outer needle main body 12 , the deformation rigidity of the distal end portion 13 of the elastic tube 16 is made greater than the deformation rigidity of the lengthwise intermediate portion 72 . In addition, when the elastic tube 16 is in a single piece state, the deformation rigidity of the distal end portion 13 need not be greater than the deformation rigidity of the intermediate portion 72. It may be rigid.

In addition, in a single product state that is not externally inserted onto the fixing portion 63b of the outer needle main body 12, the Shore D hardness of the elastic tube 16 is preferably 49 or less. That is, by setting the Shore D hardness of the elastic tube 16 to 49 or less, it is possible to reduce the possibility that the patient will feel pain even when the elastic tube 16 is pressed against the patient's skin.

Further, the length dimension A (see FIG. 2) of the tip portion 13 of the elastic tube 16 (the portion having a larger diameter than the lengthwise intermediate portion 72) is preferably 5 mm to 25 mm. That is, if the length dimension A is shorter than 5 mm, the length for holding the outer needle main body 12 by the distal end portion 13 of the elastic tube 16 may be insufficient. Further, if the length dimension A is longer than 25 mm, the portion of the elastic tube 16 where the inner needle body 12 is inserted becomes too long, and the deformation rigidity increases, which may make it difficult for the elastic tube 16 to undergo bending deformation. . On the other hand, the length dimension B (see FIG. 2) from the distal end portion 13 of the elastic tube 16 to the distal end of the connection hub 14 is preferably 5 mm to 30 mm. That is, if the length dimension B is shorter than 5 mm, the easily deformable portion of the elastic tube 16 may be too short, making it difficult to deform along the patient's skin. On the other hand, if the length dimension B is longer than 30 mm, the elastic tube 16 may bend unnecessarily, which may make it difficult to collect blood or transfuse when connecting the external channel 124, which will be described later.

The outer needle 10 of this embodiment having such a structure is combined with the inner needle 18 and used as an indwelling needle assembly 20, as shown in FIGS.

The inner needle 18 includes an inner needle main body 78 having a sharp needle point 76 at its distal end, an inner needle hub 80 attached to the proximal end of the inner needle main body 78, and is movable in the needle axial direction with respect to the inner needle main body 78. and a needle tip protector 82 attached to the .

In this embodiment, the inner needle body 78 is a hollow needle and is made of known materials such as stainless steel, aluminum, titanium, or alloys thereof. A needle tip 76 provided at the tip of the inner needle main body 78 is formed with an inclined surface that is inclined with respect to the needle axis direction, so that the living body can be punctured easily and with little irritation. A large-diameter portion 84 having a large outer diameter is formed on the outer peripheral surface of the distal end portion of the inner needle main body 78 . The large diameter portion 84 may be formed along the entire circumference in the circumferential direction by manufacturing the inner needle main body 78 by centerless processing. A pair of large-diameter portions 84, 84 are formed by processing. Note that the inner needle body may be a solid needle.

On the other hand, the inner needle hub 80 attached to the proximal end of the inner needle main body 78 includes a substantially cylindrical pedestal portion 86 in which the proximal end of the inner needle main body 78 is fixed in an embedded state, and the base portion 86 extending from the distal end of the pedestal portion 86. A substantially cylindrical protector housing portion 88 protruding with an outer diameter larger than that of the portion 86 and a tubular portion 90 protruding from the base end of the base portion 86 are integrally molded from hard synthetic resin. .

Furthermore, an inner needle cap 92 is detachably attached to the proximal opening of the tubular portion 90 . The inner needle cap 92 is a substantially stepped cylindrical synthetic resin member provided with a stepped portion at the intermediate portion in the needle axial direction. A ventilation filter (not shown) is provided inside the inner needle cap 92, and the ventilation filter has the property of permeating gas but blocking liquid. By assembling the inner needle cap 92 to the cylindrical portion 90, the base end side opening of the inner needle hub 80 is liquid-tightly covered so that back blood through the inner needle main body 78 does not leak to the outside. It has become. In addition, since the inner needle hub 80 and the inner needle cap 92 are made of a transparent material, it is possible to easily check reverse blood (flashback).

The needle tip protector 82 provided on the inner needle 18 includes a substantially cylindrical protector body 94 having a tip portion larger in diameter than the base end portion. The part is closed by a bottom wall 96 extending in the direction perpendicular to the axis. A base-side needle insertion hole 98 is formed through the center of the bottom wall 96 in the direction of the needle axis. Note that the inner diameter of the proximal needle insertion hole 98 is smaller than the outer diameter of the large diameter portions 84 and 84 of the inner needle body 78 and other than the large diameter portions 84 and 84 of the inner needle body 78 . is larger than the outer diameter of the portion.

On the other hand, the tip side opening of the protector main body 94 is closed by the lid member 100 being fixedly assembled. The lid member 100 includes a lid body portion 102 having a substantially flat plate shape. A tip-side needle insertion hole 104 penetrating in the direction is formed. An insertion protrusion 105 extending toward the distal side with a circumferential length of approximately half the circumference protrudes from the peripheral edge of the opening of the distal needle insertion hole 104 . Furthermore, a portion of the periphery of the outer peripheral edge of the lid main body 102 extends to the distal end side, and when the outer needle 10 and the inner needle 18 are assembled, the male thread 41 provided at the proximal end of the connection hub 14 and the An engaging portion 106 for engagement is integrally formed. Further, on the base end side of the lid main body 102, a substantially flat support portion 110 having an intermediate portion needle insertion hole 108 penetrating in the plate thickness direction (needle axis direction) is attached to the lid main body 102 in the needle axis direction. are integrally formed with a predetermined distance therebetween.

The inner diameters of the intermediate needle insertion hole 108 and the distal needle insertion hole 104 are larger than the outer diameters of the large diameter portions 84 , 84 of the inner needle main body 78 . In addition, the length dimension in the needle axial direction from the proximal needle insertion hole 98 to the intermediate needle insertion hole 108 is larger than the length dimension from the large diameter portions 84, 84 of the inner needle main body 78 to the distal end. . By inserting the proximal side of the inner needle main body 78 from the large diameter portions 84, 84 through the proximal side needle insertion hole 98, the intermediate portion needle insertion hole 108, and the distal side needle insertion hole 104 of the needle tip protector 82, A needle tip protector 82 is externally attached to the inner needle main body 78 so as to be movable in the needle axis direction.

Further, in the lid member 100 , a block-shaped fixing member 112 is fixedly provided at a position separated from the inner needle body 78 between the lid body portion 102 and the support portion 110 in the needle axis direction.

On the other hand, in the needle tip protector 82 , a moving member 114 that can move in the direction perpendicular to the needle axis is provided at a position on the opposite side of the fixing member 112 and the inner needle main body 78 . The moving member 114 is provided with a substantially semi-circular base portion 116 and integrally formed with a facing protrusion 118 protruding from the inner peripheral portion of the base portion 116 toward the tip side. The opposing protrusion 118 extends through the distal needle insertion hole 104 provided in the lid main body 102 and faces the insertion protrusion 105 in the direction perpendicular to the needle axis with the inner needle main body 78 interposed therebetween. A concave portion 120 is provided on the end surface of the base portion 116 on the proximal end side, and a block-shaped shielding member 122 is fixedly accommodated in the concave portion 120 . As a result, the moving member 114 (shielding member 122) and the fixed member 112 face each other in the direction perpendicular to the needle axis with the inner needle main body 78 interposed therebetween.

In particular, the moving member 114 is provided on the same side of the lid member 100 as the engagement portion 106 is provided. A moving member 114 is located above the inner needle main body 78 while being provided in the upper portion of 102 . As a result, when the outer needle 10 and the inner needle 18 are assembled, the engaging portion 106 and the opposing projection 118 sandwich the peripheral wall of the base end side opening 40 of the connection hub 14 in the plate thickness direction. there is Further, the insertion projection 105 and the fixing member 112 are positioned below the inner needle main body 78, and the insertion projection 105 and the opposing projection 118, and the fixing member 112 and the shielding member 122 sandwich the inner needle main body 78, respectively. They are positioned opposite each other in the direction perpendicular to the axis. The opposing surfaces of the insertion protrusion 105 and the opposing protrusion 118 are shaped to correspond to each other, and when the inner needle 18 is pulled out as will be described later, the insertion protrusion 105 and the opposing protrusion 118 overlap each other without any gap. It's becoming

Here, one of the fixing member 112 and the shielding member 122 is made of a magnet, and the other is made of a magnet or a ferromagnetic material such as iron, and magnetic attraction is exerted on each other. As a result, the shielding member 122 is constantly exerted with an urging force approaching the fixed member 112 , and the shielding member 122 and the movable member 114 to which the shielding member 122 is fixed are displaced in the direction approaching the fixed member 112 . is limited by the contact of the moving member 114 with the side surface of the inner needle main body 78 .

The protector main body 94, the lid member 100, the moving member 114, and the like can be preferably made of hard synthetic resin, for example.

The proximal end of the inner needle main body 78 having the structure described above is fixed to the inner needle hub 80, and the needle tip protector 82 is externally attached to the inner needle main body 78, whereby the inner needle 18 of the present embodiment is formed. is configured. The indwelling needle assembly 20 of this embodiment is constructed by inserting the inner needle 18 through the outer needle 10 .

That is, the needle tip protector 82 through which the inner needle main body 78 is inserted is accommodated in the protector accommodating portion 88 of the inner needle hub 80 , and the inner needle main body 78 extending to the distal side is positioned at the base end side opening of the outer needle 10 . It is inserted from the portion 40, penetrates the elastic valve body 43 of the hemostatic valve mechanism 42, and is inserted through the internal flow path 60 of the outer needle 10 from the proximal side to the distal side. The tip of the inner needle body 78 protrudes from the tip of the outer needle body 12 . The outer diameter of the inner needle main body 78 is substantially constant in the portions other than the large diameter portions 84 , 84 , and is substantially equal to the inner diameter of the lengthwise intermediate portion 72 of the elastic tube 16 . As a result, when the inner needle main body 78 is inserted through the lengthwise intermediate portion 72 of the elastic tube 16, the gap between them is reduced, and the amount of air entering the human body is minimized. . In this embodiment, the outer diameter dimension of the inner needle main body 78 is the same as or slightly smaller than the inner diameter dimension of the intermediate portion 72 of the elastic tube 16 .

The indwelling needle assembly 20 constructed as described above is inserted into the patient's skin in a state in which the outer needle 10 and the inner needle 18 are combined as shown in FIGS. is withdrawn, the outer needle 10 is percutaneously left in the patient's blood vessel in the state shown in FIGS.

Here, as the inner needle 18 is pulled out, the abutment between the inner needle main body 78 and the moving member 114 is released, and the blocking member 122 and the moving member 114 are fixed according to the biasing force (suction force with the fixing member 112). It is moved to the member 112 side. As a result, the shielding member 122 and the fixing member 112 are brought into contact with each other, and the opposing protrusion 118 and the insertion protrusion 105 are brought into contact with each other. As a result, the shielding member 122 and the moving member 114 move along the needle shaft of the inner needle body 78, so that the needle tip 76 of the inner needle body 78 is covered with the shielding member 122 and the moving member 114, and the needle tip protector 82 Movement of the inner needle body 78 toward the distal end side can be restricted.

Further, by moving the moving member 114 toward the fixing member 112 (inner needle main body 78 side), the clamping of the peripheral wall of the proximal opening 40 of the connection hub 14 between the engaging portion 106 and the opposing projection 118 is released. , the engagement between the engaging portion 106 and the male thread 41 can be released. That is, in the needle tip protector 82 of the present embodiment, the needle tip 76 of the inner needle body 78 is protected by the needle tip protector 82 as the inner needle 18 is pulled out from the outer needle 10, and the needle tip protector 82 and the outer needle 18 are pulled out. The engagement with needle 10 (connection hub 14) can also be disengaged.

Further, by pulling out the inner needle main body 78, the bottom wall 96 of the protector main body 94 and the large diameter portions 84, 84 of the inner needle main body 78 are engaged. As a result, movement of the inner needle body 78 toward the proximal end side with respect to the needle tip protector 82 is also restricted. Therefore, in the indwelling needle assembly 20 of this embodiment, the inner needle 18 can be removed from the outer needle 10 while the needle tip 76 of the inner needle main body 78 is protected by the needle tip protector 82 .

Then, as shown in FIG. 9, an external flow path 124 such as a luer lock syringe is connected from the proximal opening 40 of the connection hub 14 of the outer needle 10 placed in the patient's blood vessel. The pusher 50 of the hemostatic valve mechanism 42 is pushed forward by the male luer 126 to push open the slit 45 of the elastic valve body 43 . As a result, the internal flow path 60 and the external flow path 124 are brought into communication with each other, and blood sampling and transfusion are started. Note that the external flow path is not limited to the luer lock type, and may be of the slip lock type or the like. Further, by removing the external channel 124, the elastic valve body 43 is closed again based on the elastic restoring action.

Here, the outer needle 10 of this embodiment includes an easily elastically deformable elastic tube 16 between the outer needle main body 12 and the connection hub 14, and the elastic tube 16 is deformed along the patient's skin. Therefore, by taping the location where the elastic tube 16 is arranged, it can be stably fixed to the patient. In addition, since the soft elastic tube 16 having a hardness equal to or less than a predetermined hardness is pressed against the patient during taping, the possibility that the patient feels pain can be reduced.

In particular, in the indwelling needle described in Patent Document 2, the outer needle main body is fixed to the needle hub, and the elastic tube is externally inserted into the needle hub. The distal end portion of the needle hub 13 is used as the needle hub 13, and the needle hub 13 and the elastic tube 16 are integrally formed. Since the distal end portion 13 of the elastic tube 16 is directly placed over the proximal end portion (fixed portion 63b) of the outer needle main body 12, an increase in the diameter of the elastic tube 16 is suppressed. As a result, the elastic tube 16 can reduce the pressing force on the patient's skin when it is taped and fixed to the patient's skin, thereby suppressing pain felt by the patient. In addition, since the fixed portion 63b of the outer needle main body 12 is press-fitted into the distal end portion 13 of the elastic tube 16 and fixed in close contact with each other, there is no need for bonding or welding, which improves the efficiency of assembly. Improvements can be made.

Furthermore, by forming the outer needle main body 12 from a member having flexibility, for example, when connecting the outer needle 10 to the external flow path 124, the outer needle main body 12 and the elastic tube 16 can be easily grasped when the outer needle 10 is grasped. can be deformed, for example, if the outer needle body is made of a hard material, the patient may feel pain by moving the outer needle 10, but the possibility of feeling such pain is stabilized. can be reduced. In addition, since the outer needle body 12 is flexible, the deformation rigidity of the connecting portion between the outer needle body 12 and the elastic tube 16 does not significantly increase. is connected, deformation of the elastic tube 16 is possible.

Furthermore, the elastic tube 16 is connected to the outer needle main body 12 so that the deformation rigidity of the distal end portion 13 is greater than that of the lengthwise intermediate portion 72 and the proximal end portion 58 . As a result, both the stability of taping fixation at the distal end portion 13 of the elastic tube 16 and the ease of elastic deformation of the longitudinal intermediate portion 72 and the proximal end portion 58 along the patient's skin can be achieved. That is, the elastic tube 16 of this embodiment stably supports the outer needle main body 12 at the distal end portion 13 and is stably fixed to the skin by taping, and elastically deforms at the intermediate portion 72 and the proximal end portion 58 . are easily allowed, and by making the functions different in the length direction, both of these functions are achieved.

When the elastic tube 16 is connected to the outer needle main body 12, the distal end portion 13 supporting the outer needle main body 12 has a larger diameter than the intermediate portion 72 and the proximal end portion 58. Both the function of supporting the outer needle body 12 and the function of deforming the intermediate portion 72 and the proximal end portion 58 can be realized more stably.

In addition, in this embodiment, the connecting portion 22 is provided at the proximal end portion of the outer needle main body 12, that is, the first and second raised portions 26a and 26b are spaced apart in the needle axis direction, and there is a relatively A fixing recessed groove 24 which is recessed is formed. Then, the distal end side thick portion 68 of the distal end portion 13 of the elastic tube 16 enters into the fixing recessed groove 24 to connect the outer needle main body 12 and the elastic tube 16 (needle hub 13), thereby providing an anchoring effect. is stably exerted, and the outer needle main body 12 and the elastic tube 16 (needle hub 13) can be connected more firmly.

Furthermore, when the tip portion 13 of the elastic tube 16 is provided with the R surface 62a, or the tip side end surface of the second protuberance 26b is formed into a tapered surface 27b, and these are angular. The patient may be less likely to feel pain compared to In particular, since the outer diameter dimension of the R surface 62a is larger than the outer diameter dimension of the second protuberance 26b, the R surface 62a (the distal end portion 13 of the elastic tube 16) is more comfortable for the patient than the second protuberance 26b. Since it is easy to press against the skin of the patient, the possibility that the patient will feel pain can be further reduced.

Furthermore, since the internal flow path 60 of the outer needle 10 is provided with the hemostatic valve mechanism 42, for example, when the internal flow path 60 is shut off, the elastic tube 16 cannot necessarily be closed with a hard clamp or the like. not necessary. Therefore, it can be prevented that the patient feels pain due to the clamp or the like being pressed against the patient's skin. In particular, since the proximal end portion 58 of the elastic tube 16 is provided with the tapered surface 75 to increase the inner diameter, a space for the elastic deformation of the elastic valve body 43 can be stably secured.

In addition, since the elastic tube 16 has a diameter smaller than that of the connection hub 14, the operation of pinching the connection hub 14 to connect the external flow path 124 when the outer needle 10 is indwelling can be facilitated.

10 and 11 show an indwelling needle 128 as a second embodiment of the invention. The indwelling needle 128 includes an outer needle main body 130 as a hollow needle and an elastic tube 132. A connection hub 14 having the same structure as that of the first embodiment is connected to the proximal end of the elastic tube 132. It is designed to be In the following description, members and portions that are substantially the same as those of the above embodiment are denoted by the same reference numerals as those of the above embodiment, and detailed description thereof will be omitted.

As shown in FIGS. 12 and 13, the outer needle body 130 in this embodiment has the same basic structure as the outer needle body (12) in the first embodiment. That is, a first raised portion 136 and a second raised portion 138 are provided along the entire circumference of the base end portion of the outer needle main body 130 . An annular fixed recessed groove 24 is formed between the two in the axial direction.

In addition, in the present embodiment, a tapered surface 27b, which is an inclined surface on the distal end side of the second raised portion 138, is formed at the proximal end portion of the exposed portion 63a of the outer needle main body 130. As shown in FIG. That is, the second raised portion 138 has an outer peripheral surface shape formed by a tapered surface 27b in which the outer diameter dimension of the tip side portion gradually decreases toward the tip, and the thickness dimension of the peripheral wall of the outer needle main body 130 is It tapers off towards the tip. Furthermore, a plurality of recessed grooves 140 are formed in the second protuberance 138 so as to have a predetermined width in the circumferential direction and extend in the axial direction with a predetermined width in the circumferential direction. With these plurality of grooves 140, the second raised portion 138 has a shape in which the height of the plurality of rib-shaped projections 142 extending in the longitudinal direction gradually decreases toward the distal end side of the outer needle main body 130. It has a structure in which it is integrally formed on the outer peripheral surface of the peripheral wall portion.

The proximal end portion (fixed portion 63b) of the outer needle main body 130 having such a structure is press-fitted into the distal end portion 13 of the elastic tube 132, thereby fixing the outer needle main body 130 and the elastic tube 132 to each other. ing. In the first embodiment, the proximal end portion (fixed portion 63b) of the outer needle main body (12) is press-fitted into the distal end portion 13 of the elastic tube (16) to form the distal thick portion 68 and Although the gap (73) is formed between the first protuberance (26a) and the axial direction, in this embodiment, for example, the first protuberance (136) is fitted in advance on the inner peripheral surface of the elastic tube (132). By forming an annular recessed groove 144 for fitting, such a gap (73) is prevented from being formed.

The indwelling needle 128 having the outer needle main body 130 structured as described above can also be used as an indwelling needle assembly in combination with the inner needle (18) structured similarly to the first embodiment. It is possible, and effects similar to those of the first embodiment can be exhibited. In particular, in the present embodiment, the second protuberance 138 is configured by a plurality of rib-like protrusions 142 extending in the longitudinal direction in a plate shape with a predetermined thickness, thereby making the second protuberance 138 excessively high. The rib-like protrusion 142, which does not have rigidity but whose height dimension gradually decreases from the proximal side to the distal side, gradually reduces the rigidity from the proximal side to the distal side of the second raised portion 138. The rigidity can be changed so as to fit the tip portion of the thin cylindrical outer needle main body 130 .

As a result, at the proximal end of the exposed portion of the outer needle main body 130 where stress tends to concentrate during use, a sudden change in rigidity is avoided, and the stress is dispersed in the longitudinal direction of the outer needle main body 130. , durability and strength resistance can be improved. Moreover, the concave grooves 140 extending in the longitudinal direction provided between the rib-like projections 142, 142 adjacent in the circumferential direction also exert a thinning effect during molding of the outer needle main body 130, thereby preventing sink marks and voids. A technical effect such as avoidance of resin molding defects can also be achieved.

Furthermore, as another embodiment, as shown in FIG. 14, an indwelling needle 150 or an indwelling needle assembly 150' having the indwelling needle 150 includes a cover member 152 that covers at least one of the needle hub 13 or the elastic tube 16. may be configured to have With such a configuration, resistance to external force and blood pressure flowing through the internal flow path is increased. The method of mounting cover member 152 covering needle hub 13 or elastic tube 16 is not particularly limited. The hardness of the needle hub 13 is preferably the same or higher than that of the needle hub 13, although the hardness of the needle hub 13 is not particularly limited.

Although the embodiments of the present invention have been described above, the present invention is not to be construed as being limited by the specific descriptions in such embodiments, and various changes, modifications, improvements, etc. based on the knowledge of those skilled in the art. It is possible to implement in a mode in which

For example, in the above-described embodiment, in the elastic tubes 16, 132, the longitudinal intermediate portion 72 and the proximal end portion 58 have smaller outer diameters than the distal end portion 13, but the indwelling needle shown in FIG. 160, by covering the distal end portion 13 of the elastic tube 162 over the proximal end portion (fixed portion) 63b of the outer needle main body 12, the maximum outer diameter portion 64 of the distal end portion 13 is elastically The proximal end including the lengthwise intermediate portion 72 of the tube 162 may have a substantially constant outer diameter. By adopting such an elastic tube 162, unevenness on the outer peripheral surface of the elastic tube 162 can be further reduced or substantially eliminated, so that the possibility of getting caught on the patient's skin, for example, can be more effectively reduced.

Further, in the above-described embodiment, the distal end portion 13 of the elastic tube 16, 132 is covered from the outside on the base end portion (fixed portion) 63b of the outer needle main body 12, 130, but the outer needle main body is formed of a soft material. When the elastic tube has flexibility, a configuration may be added in which the distal end portion of the elastic tube is covered with the proximal end portion of the outer needle main body from the outside. In such a case, for example, a concave portion extending in the circumferential direction is provided on the outer peripheral surface of the elastic tube, and a projection projecting inwardly is provided on the inner peripheral surface of the outer needle main body so that the outer needle is inserted into the concave portion of the elastic tube. By fitting the projection of the main body, the anchor effect similar to that of the above embodiment can be exhibited. In this case, the protrusion projecting from the inner peripheral surface of the outer needle main body to the inner peripheral side can also be grasped as a fixed portion provided on the proximal end side of the hollow needle. In addition, the recessed portion and the protruding portion may be provided on the surfaces opposite to each other, and they do not need to extend in the circumferential direction.

Furthermore, in the above embodiment, the inner needle 18 is combined with the outer needles 10, 128 and used as the indwelling needle assembly 20, but in the present invention, the inner needle is not essential, and only the outer needles 10, 128 can be manufactured and marketed. As the material of the outer needle bodies 12 and 130, a material such as metal or hard synthetic resin that easily punctures the patient's skin may be used, or depending on the application, the outer needle 10 may be used without combining the inner needle 18 with the inner needle 18. , 128 alone. Even in such a case, the effect of reducing the pain felt by the patient can be exhibited by indwelling the flexible outer needle main body in the patient's blood vessel.

Furthermore, in the above-described embodiment, the connecting portion 22 provided at the proximal end portion of the outer needle main body 12, 130 includes the first and second connecting portions protruding to the outer peripheral side along the entire outer peripheral surface of the outer needle main body 12, 130. Although it is configured such that the two protrusions 26a, 26b, 136, 138 are spaced apart in the longitudinal direction, the present invention is not limited to such an aspect. In other words, the raised portion may be partially provided on the periphery as in the above embodiment, or the recessed portion may be provided. However, in the present invention, the connecting portion provided at the proximal end portion of the outer needle body is not essential, and the outer needle body may be simply straight.

Further, in the above embodiment, the hemostasis valve mechanism 42 was provided inside the connection hub 14, but in the present invention, the hemostasis valve mechanism is not essential. Even if hemostasis is required, for example, instead of or in combination with a hemostatic valve mechanism, an elastic tube is closed with a clamp to prevent backflow of blood during puncture of an indwelling needle. You may

Furthermore, the structure of the needle tip protector is not limited to that described in the above embodiments. That is, in the needle tip protector 82 described in the above embodiment, the biasing force is exerted by magnetic force, but a spring or the like may be employed to exert the biasing force by elastic force. A needle tip protector having an arm-shaped protection portion as described may be employed. However, the needle tip protector is not essential in the present invention.

Furthermore, in the second embodiment, in the second raised portion 138, the recessed grooves 140 opening in the outer peripheral surface (tapered surface 27b) extend in the axial direction and are arranged in a plurality of rows at predetermined intervals in the circumferential direction. Although provided, the shape of the groove is not limited at all, and may be, for example, an annular groove extending continuously over the entire circumference in the circumferential direction.

10: outer needle (indwelling needle), 12, 130: outer needle body (hollow needle), 13: needle hub, 14: connection hub, 16, 132, 162: elastic tube, 18: inner needle, 20, 150': Indwelling needle assembly 22: connecting portion 24: fixed concave groove (annular concave portion) 26a, 136: first raised portion 26b, 138: second raised portion 27b: tapered surface 43: elastic valve body (Hemostasis valve) 50: plunger 60: internal flow path 62a: R surface 63a: exposed portion 63b: fixed portion 68: distal thick portion 72: intermediate portion 75: tapered surface 78 : inner needle body, 80: inner needle hub, 124: external flow path, 128, 150, 160: indwelling needle, 140: concave groove, 142: rib-like projection, 152: cover member

Claims (9)

A hollow needle that is percutaneously inserted into a blood vessel, a needle hub in which the hollow needle is fixed, a connection hub that is connected to an external flow path, and a bending deformation that connects the needle hub and the connection hub. It consists of an elastic tube capable of
A distal portion of the elastic tube defines the needle hub, and the elastic tube and the needle hub are formed as a single piece.and
The hollow needle comprises an exposed portion not covered with the elastic tube and a fixed portion covered with the elastic tube, and the fixed portion of the hollow needle has a larger outer diameter than the exposed portion at the proximal end. having a first ridge An indwelling needle characterized by: 2. The indwelling needle according to claim 1, wherein the needle hub has a hardness of Shore D49 or less when the hollow needle is not fixed. The indwelling needle according to claim 1 or 2, wherein the fixing portion is press-fitted into the needle hub. A second protruding portion having an outer diameter smaller than that of the first protruding portion and larger than that of the exposed portion is provided on the tip side of the hollow needle relative to the first protruding portion, The indwelling needle according to any one of claims 1 to 3, wherein an annular recess is formed between the first raised portion and the second raised portion. The outer peripheral surface of the distal end portion of the needle hub has an R surface shape that gradually increases in diameter toward the proximal end side, and the outer diameter dimension of the distal end portion of the R surface is the second protrusion of the hollow needle. 5. The indwelling needle according to claim 4 , wherein the outer diameter of the indwelling needle is larger than that of the The indwelling needle according to any one of claims 1 to 5 , wherein the proximal end of the fixing portion of the hollow needle is positioned closer to the proximal side than the proximal end of the needle hub. The indwelling needle according to any one of claims 1 to 6 , wherein the outer peripheral surface of the proximal end portion of the exposed portion of the hollow needle has a tapered shape with a diameter gradually decreasing toward the distal end side. A plurality of concave grooves extending in the length direction of the hollow needle are provided in the circumferential direction at the proximal end of the exposed portion of the hollow needle having the tapered outer peripheral surface. 8. The indwelling needle according to claim 7 , wherein the end portion has a peripheral structure having a plurality of rib-like projections whose height dimension changes in the longitudinal direction of the hollow needle. The indwelling needle according to any one of claims 1 to 8 , wherein a hemostatic valve is arranged in an internal channel extending from the hollow needle to the connection hub and connected to the external channel.

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