JP7396843B2 - catheter assembly - Google Patents

Description

The present invention relates to catheter assemblies.

Patent Document 1 discloses a catheter assembly (indwelling needle) including a needle member and a catheter member. The needle member includes an inner needle having a needle tip at its tip, and a hollow needle hub fixed to the proximal end of the inner needle. A blade surface extending in the proximal direction from the cutting edge located at the tip of the inner needle to the blade base is formed at the tip of the inner needle. The tip opening of the inner needle is formed in the blade surface. The catheter member has a tubular catheter shaft into which the inner needle is inserted, and a hollow catheter hub into which the inner needle is inserted and which is fixed to the proximal end of the catheter shaft.

Japanese Patent Application Publication No. 2009-233007

By the way, in a procedure using a catheter assembly, the inner needle and catheter shaft are punctured into a blood vessel with the inner needle protruding from the tip of the catheter shaft. At this time, the user confirms that the inner needle has secured the blood vessel by visually observing the backflow (flashback) of blood into the lumen of the needle hub via the lumen of the inner needle.

On the other hand, when the cutting edge pierces the rear wall of the blood vessel, the opening at the tip of the inner needle is completely blocked by the rear wall of the blood vessel, thereby stopping the backflow of blood into the lumen of the inner needle. This allows the user to know that the inner needle is stuck in the rear wall of the blood vessel. However, in conventional catheter assemblies, when the tip of the inner needle is located in the blood vessel with the cutting edge stuck into the rear wall of the blood vessel, the needle hub is inserted through the inner lumen of the inner needle. Vascular backflow into the lumen is seen. Therefore, the user was unable to accurately determine the penetration of the inner needle into the rear wall of the blood vessel.

The present invention has been made in consideration of these problems, and provides a catheter assembly that can confirm whether the inner needle is securing the blood vessel and can accurately determine whether the inner needle has penetrated into the rear wall of the blood vessel. The purpose is to provide

One aspect of the present invention is a catheter assembly including a tubular inner needle and a tubular catheter shaft through which the inner needle is inserted, the needle hub being fixed to the proximal end of the inner needle. and a support part that is inserted through the inner cavity of the inner needle and is fixed to the needle hub, and the tip of the inner needle has a blade surface that is inclined with respect to the axis of the inner needle. , the blade surface has a blade tip located at the most distal end of the inner needle, and a blade base located at the proximal end of the blade surface in the axial direction, and the catheter assembly is formed on the blade surface. The inner needle has a closing part that closes at least the blade side of the tip opening of the inner needle, and an introduction hole for guiding blood into the inner lumen of the inner needle is provided on the tip side of the inner needle than the blade side. In the axial direction of the inner needle, the proximal end of the introduction hole is located on the distal side of the proximal end of the distal opening of the inner needle, and the closing part is provided at the distal end of the support part. It is a catheter assembly.

According to the present invention, when the distal end of the catheter assembly is punctured into a blood vessel and the introduction hole of the inner needle is located within the blood vessel, blood within the blood vessel is guided from the introduction hole to the lumen of the inner needle. Therefore, the backflow of blood through the lumen of the inner needle makes it possible to confirm that the inner needle has secured the blood vessel. Furthermore, at least the blade end side of the distal opening of the inner needle is closed with a closing portion, and the proximal end of the introduction hole is located on the distal side of the distal opening of the inner needle. Therefore, when the cutting edge pierces the rear wall of the blood vessel, the backflow of blood into the lumen of the inner needle stops when the introduction hole is completely blocked by the rear wall of the blood vessel. In other words, even if the introduction hole is completely blocked by the rear wall of the blood and the tip of the tip opening of the inner needle is located inside the blood vessel, blood will flow back into the lumen of the inner needle. stops. Thereby, by confirming that the backflow of blood through the lumen of the inner needle has stopped, it is possible to accurately determine whether the needle tip has penetrated into the rear wall of the blood vessel.

FIG. 1 is a perspective view of a catheter assembly according to an embodiment of the invention. FIG. 2 is an exploded perspective view of the catheter assembly of FIG. 1; FIG. 2 is a longitudinal cross-sectional view of the catheter assembly of FIG. 1; FIG. 4A is a perspective view of the distal end of the inner needle, and FIG. 4B is a longitudinal cross-sectional view of the distal end of the catheter assembly. 5A is a first illustration of a procedure for the catheter assembly of FIG. 1, and FIG. 5B is a second illustration of a procedure for the catheter assembly of FIG. 1. FIG. 6A is a plan view of the distal end of a catheter assembly including a needle member according to a modified example, and FIG. 6B is a longitudinal cross-sectional view taken along line VIB-VIB in FIG. 6A. FIG. 7 is a partially omitted vertical cross-sectional view of a catheter assembly including a needle member according to another modification. 8A is a longitudinal cross-sectional view of the distal end of the catheter assembly of FIG. 7, and FIG. 8B is a cross-sectional view taken along line VIIIB-VIIIB of FIG. 8A.

Hereinafter, preferred embodiments of the catheter assembly according to the present invention will be described with reference to the accompanying drawings.

A catheter assembly 10 according to an embodiment of the present invention is configured as an indwelling needle for administering an infusion (medicinal solution) into a blood vessel of a patient (living body). As shown in FIGS. 1-3, catheter assembly 10 includes a catheter member 12 and a needle member 14. As shown in FIGS. Catheter member 12 includes a catheter shaft 16 and a catheter hub 18 secured to the proximal end of catheter shaft 16 .

The catheter shaft 16 is a flexible tubular member that can be continuously inserted into a patient's blood vessel. Catheter shaft 16 has a lumen 16a extending along its entire length in the axial direction. A distal end opening 16b communicating with the lumen 16a is formed at the distal end of the catheter shaft 16.

The constituent material of the catheter shaft 16 is not particularly limited, but a transparent resin material, particularly a soft resin material, is suitable, such as polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene copolymer, etc. (ETFE), fluororesins such as perfluoroalkoxyfluororesin (PFA), olefin resins such as polyethylene and polypropylene, or mixtures thereof, polyurethane, polyester, polyamide, polyether nylon resin, olefin resin and ethylene- Examples include mixtures with vinyl acetate copolymers.

The catheter hub 18 is formed in a hollow (cylindrical) shape. As shown in FIG. 3, a first attachment hole 20 is formed at the distal end of the catheter hub 18 to which the proximal end of the catheter shaft 16 is attached. The outer circumferential surface of the proximal end of the catheter shaft 16 is fixed to the wall surface forming the first attachment hole 20 by appropriate fixing means such as caulking, fusion, adhesion, or the like.

A lumen 18 a that communicates with the lumen 16 a of the catheter shaft 16 is formed in the catheter hub 18 on the proximal side of the first attachment hole 20 . The lumen 18a of the catheter hub 18 opens at the proximal end of the catheter hub 18. Although not shown in the drawings, a hemostasis valve, a seal member, and a plug are provided in the lumen 18a of the catheter hub 18. The catheter hub 18 is transparent so that blood flowing into the lumen 18a of the catheter hub 18 can be visually recognized from outside the catheter hub 18. That is, the catheter hub 18 is made of a transparent or translucent material.

Catheter hub 18 is preferably constructed of a harder material than catheter shaft 16. The constituent material of the catheter hub 18 is not particularly limited, but includes thermoplastic materials such as polypropylene, polycarbonate, polyamide, polysulfone, polyarylate, methacrylate-butylene-styrene copolymer, polyurethane, acrylic resin, and ABS resin. Resin can be suitably used.

In FIGS. 1 to 3, the needle member 14 includes an inner needle 22, a needle hub 24 fixed to the proximal end of the inner needle 22, and a closing portion 26 provided on the inner needle 22. The inner needle 22 is a tubular member that is rigid enough to puncture the patient's skin. As shown in FIG. 3, the inner needle 22 has a lumen 22a extending along the axial direction. The inner needle 22 is inserted into the lumen 16a of the catheter shaft 16 and the lumen 18a of the catheter hub 18 in the initial state (assembled state) of the catheter assembly 10.

Examples of the constituent material of the inner needle 22 include metal materials such as stainless steel, aluminum, aluminum alloy, titanium, and titanium alloy. The inner needle 22 is formed sufficiently longer than the catheter shaft 16, and protrudes from the distal end opening 16b of the catheter shaft 16 in the initial state of the catheter assembly 10 (see FIGS. 1 and 3).

As shown in FIGS. 4A and 4B, a blade surface 28 that is inclined with respect to the axis of the inner needle 22 is formed at the tip of the inner needle 22. The blade surface 28 has a cutting edge 28a located at the most distal end of the inner needle 22, and a cutting base 28b located at the proximal end of the blade surface 28 in the axial direction. The blade surface 28 extends flatly. However, the blade surface 28 may extend in a concave curve. The blade surface 28 is formed with an elliptical tip opening 22b that communicates with the inner cavity 22a of the inner needle 22. The tip opening 22b of the inner needle 22 extends along the direction in which the blade surface 28 extends. A blood introduction groove (not shown) may be formed on the outer surface of the inner needle 22 to guide blood into the lumen 18a of the catheter hub 18 through the space between the inner needle 22 and the catheter shaft 16.

In FIG. 3, the needle hub 24 is formed into a hollow (cylindrical) shape. The needle hub 24 may be made of the same material as the catheter hub 18 described above. The needle hub 24 has an inner needle support portion 30 forming a distal end thereof, and a needle hub body 32 extending from the inner needle support portion 30 toward the proximal end.

A second attachment hole 34 is formed in the inner needle support portion 30 to which the proximal end portion of the inner needle 22 is attached. The outer peripheral surface of the proximal end of the inner needle 22 is fixed to the wall surface forming the second attachment hole 34 by appropriate fixing means such as fusion, adhesion, and fitting.

The needle hub body 32 is formed in a size and shape that makes it easy for a user to grasp. The needle hub 24 is formed with a lumen 25 that communicates with the lumen 22a of the inner needle 22 and into which blood guided from the inner needle 22 flows. The lumen 25 of the needle hub 24 is provided with a filter member 36 that blocks the flow of blood while allowing the flow of air. At least a portion of the needle hub 24 (for example, the needle hub body 32) is transparent so that blood flowing into the lumen 25 of the needle hub 24 is visible from the outside of the needle hub 24. That is, the needle hub 24 is constructed from a transparent or translucent material.

In FIGS. 4A and 4B, the closing portion 26 is provided in the inner needle 22 so as to close at least the blade base 28b side of the tip opening 22b formed in the blade surface 28 of the inner needle 22. The closing portion 26 does not close the cutting edge 28a side of the distal end opening 22b of the inner needle 22. That is, the space in the distal end opening 22b of the inner needle 22 that is not closed by the closing part 26 functions as the introduction hole 38 for guiding blood into the lumen 22a of the inner needle 22. There is one introduction hole 38. However, a plurality of introduction holes 38 may be provided. Moreover, the shape and size of the introduction hole 38 can be changed as appropriate.

The closing portion 26 is formed into a plate shape. The closing portion 26 is located at the distal end opening 22b of the inner needle 22 and is joined to the inner needle 22 by suitable joining means such as fusion, adhesion, and welding. The outer peripheral edge of the closing portion 26 is in liquid-tight contact with a wall surface forming the distal end opening 22b of the inner needle 22. The outer surface 26a of the closing portion 26 facing toward the distal end is flush with the blade surface 28. In other words, the outer surface 26a of the closing portion 26 is continuous with the blade surface 28 without any difference in level. However, the outer surface 26a of the closing portion 26 may be located on the proximal side (the side where the lumen 22a of the inner needle 22 is located) than the blade surface 28. The closing portion 26 is formed to become thinner from the blade base 28b side to the blade edge 28a side (see FIG. 4B).

The introduction hole 38 is provided closer to the tip than the blade base 28b. In the axial direction of the inner needle 22, the proximal end P1 of the introduction hole 38 (the hole forming part of the closing part 26) is located closer to the distal side than the proximal end P2 of the distal opening 22b of the inner needle 22. In the axial direction of the inner needle 22, the proximal end P1 of the introduction hole 38 is located closer to the distal end than the center P3 of the distal opening 22b of the inner needle 22. The introduction hole 38 is provided on the tip side of the blade surface 28. In other words, the introduction hole 38 is located near the cutting edge 28a.

The opening area of the introduction hole 38 is smaller than the flow path cross-sectional area of the inner cavity 22a of the inner needle 22 on the proximal end side of the closing portion 26. Specifically, the ratio of the opening area of the introduction hole 38 to the cross-sectional area of the flow path on the proximal side of the occlusion part 26 in the inner lumen 22a of the inner needle 22 is preferably 10% or more and 50% or less, and 20% or more and 40% or more. % or less, more preferably about 30%.

Next, a procedure using the catheter assembly 10 configured in this manner will be described. Note that in the initial state of the catheter assembly 10, the blade surface 28 projects from the distal end opening 16b of the catheter shaft 16 in the distal direction. As shown in FIG. 5A, the user punctures the blood vessel 102 through the skin 100 with the catheter assembly 10 in its initial state.

When the cutting edge 28a penetrates the front wall 103 of the blood vessel 102 and the introduction hole 38 is located inside the blood vessel 102, the blood in the blood vessel 102 flows from the introduction hole 38 through the lumen 22a of the inner needle 22 into the needle hub 24. Flow back into cavity 25. Therefore, the user can know that the blood vessel 102 has been secured by visually observing the backflow (flashback) of blood into the lumen 25 of the needle hub 24 from outside the needle hub 24.

In the puncturing operation, when the cutting edge 28a pierces the rear wall 104 of the blood vessel 102 as shown in FIG. Backflow of blood into lumen 22a is stopped. At this time, even if the blade base 28b side of the distal opening 22b of the inner needle 22 is located within the blood vessel 102, the blade base 28b side of the distal opening 22b is occluded by the occlusion part 26, so the inside of the blood vessel 102 is Blood does not flow into the lumen 22a of the inner needle 22.

Then, the user visually confirms that the backflow (flashback) of blood to the lumen 25 of the needle hub 24 has stopped from the outside of the needle hub 24, and can confirm that the inner needle 22 is stuck in the rear wall 104 of the blood vessel 102. You can know something. In this case, the user pulls back (retracts) the catheter assembly 10 until backflow of blood into the lumen 25 of the needle hub 24 is again observed.

After confirming that the inner needle 22 has secured the blood vessel 102, the user removes the inner needle 22 from the catheter shaft 16.

In this case, this embodiment has the following effects.

The catheter assembly 10 includes a closing portion 26 that is formed on the blade surface 28 and closes at least the blade base 28b side of the tip opening 22b of the inner needle 22. An introduction hole 38 for guiding blood into the lumen 22a of the inner needle 22 is formed on the distal end side of the blade base 28b of the inner needle 22, and the proximal end P1 of the introduction hole 38 is formed in the axial direction of the inner needle 22. is located on the distal side of the proximal end P2 of the distal opening 22b of the inner needle 22.

According to this configuration, when the distal end of the catheter assembly 10 is punctured into the blood vessel 102 and the introduction hole 38 of the inner needle 22 is located within the blood vessel 102, blood in the blood vessel 102 flows from the introduction hole 38 into the inner needle 22. is guided into the lumen 22a of the lumen 22a. Therefore, by the backflow of blood through the lumen 22a of the inner needle 22, it is possible to confirm that the inner needle 22 has secured a blood vessel.

Further, at least the blade end 28b side of the distal opening 22b of the inner needle 22 is closed with the closing part 26, and the proximal end P1 of the introduction hole 38 is located on the distal side of the proximal end P2 of the distal opening 22b of the inner needle 22. . Therefore, when the cutting edge 28 a pierces the rear wall 104 of the blood vessel 102 , the introduction hole 38 is completely blocked by the rear wall 104 of the blood vessel 102 , and the tip opening 22 b of the inner needle 22 is connected to the blood vessel 102 on the blade base 28 b side. Even if the blood is located inside the lumen 22a of the inner needle 22, the backflow of blood to the lumen 22a of the inner needle 22 is stopped. Thereby, by confirming that the backflow of blood through the lumen 22a of the inner needle 22 has stopped, it is possible to accurately determine whether the inner needle 22 has penetrated into the rear wall 104 of the blood vessel 102.

The introduction hole 38 is located on the tip side of the blade surface 28.

According to such a configuration, the penetration of the inner needle 22 into the rear wall 104 of the blood vessel 102 can be detected with higher accuracy.

The blocking part 26 does not block the distal end portion of the distal opening 22b of the inner needle 22, and the introduction hole 38 is formed by the part of the distal opening 22b of the inner needle 22 that is not blocked by the blocking part 26. .

According to such a configuration, the introduction hole 38 can be easily formed.

The closing part 26 is joined to the inner needle 22.

According to such a configuration, the configuration of the catheter assembly 10 can be simplified.

Next, a needle member 14A according to a modified example shown in FIGS. 6A and 6B will be described. As shown in FIGS. 6A and 6B, the needle member 14A includes an inner needle 22 and a closing part 42. The above-mentioned needle hub 24 (see FIG. 3) is fixed to the proximal end of the inner needle 22.

The closing portion 42 completely closes the tip opening 22b of the inner needle 22. The closing portion 42 is located at the distal end opening 22b of the inner needle 22 and is joined to the inner needle 22 by appropriate joining means such as fusion, adhesion, and welding. The closing portion 42 is formed into a plate shape, and its outer peripheral surface is in liquid-tight contact with the wall surface forming the tip opening 22b of the inner needle 22 over the entire circumference. The outer surface 42a of the closing portion 42 is flush with the blade surface 28. In other words, the outer surface 42a of the closing portion 42 is continuous with the blade surface 28 without any difference in level. However, the outer surface 42a of the closing portion 42 may be located on the proximal side (the side where the lumen 22a of the inner needle 22 is located) than the blade surface 28. The closing portion 42 is formed thinner from the blade base 28b side toward the blade edge 28a side.

One introduction hole 44 for guiding blood into the lumen 22a of the inner needle 22 is formed near the cutting edge 28a of the inner needle 22. A plurality of introduction holes 44 may be provided. The size and shape of the introduction hole 44 can be changed as appropriate. The introduction hole 44 is positioned offset from the blade surface 28 in the circumferential direction of the inner needle 22 . Specifically, the introduction hole 44 is positioned deviated by 180 degrees in the circumferential direction of the inner needle 22 with respect to the center line L connecting the cutting edge 28a and the cutting edge 28b. In the axial direction of the inner needle 22, the proximal end P4 of the introduction hole 44 is located closer to the distal end than the proximal end P5 of the distal end opening 22b of the inner needle 22. In the axial direction of the inner needle 22, the proximal end P4 of the introduction hole 44 in the axial direction is located closer to the distal end than the center P6 of the distal opening 22b of the inner needle 22.

According to the catheter assembly 10 including the needle member 14A, similarly to the needle member 14 described above, it is possible to confirm that the inner needle 22 secures the blood vessel, and to prevent the inner needle 22 from penetrating the rear wall 104 of the blood vessel 102. You can know with good accuracy.

Further, the catheter assembly 10 including the needle member 14A has the following effects.

The introduction hole 44 is positioned offset from the blade surface 28 in the circumferential direction of the inner needle 22 .

According to such a configuration, the introduction hole 44 can be easily formed.

The introduction hole 44 is located 180° offset from the center line L connecting the cutting edge 28a and the cutting edge 28b.

According to such a configuration, the distance between the distal end opening 22b of the inner needle 22 and the introduction hole 44 can be made relatively long, so that a decrease in the rigidity of the distal end portion of the inner needle 22 can be suppressed.

In the axial direction of the inner needle 22, the proximal end P4 of the introduction hole 44 is located closer to the distal end than the center P6 of the distal opening 22b of the inner needle 22.

According to such a configuration, the penetration of the inner needle 22 into the rear wall 104 of the blood vessel 102 can be detected with higher accuracy.

The closing portion 42 completely closes the tip opening 22b of the inner needle 22.

According to such a configuration, it is possible to prevent blood from flowing into the lumen 22a of the inner needle 22 from the tip opening 22b of the inner needle 22.

Next, a needle member 14B according to another modification shown in FIGS. 7 to 8B will be described. As shown in FIG. 7, the needle member 14B includes an inner needle 22, a needle hub 50, a closure portion 26, and a support portion 56. The needle hub 50 includes the inner needle support portion 30 and the needle hub body 32 described above, and an annular fixing member 58 fitted into an opening on the proximal end side of the needle hub body 32. The above-described filter member 36 is disposed in the inner cavity of the fixing member 58.

As shown in FIG. 8A, the closing part 26 is provided separately from the inner needle 22. In other words, the closure part 26 is not joined to the inner needle 22. The closing portion 26 is formed in the same manner as the closing portion 26 described above, except that it is not joined to the inner needle 22. That is, the inner needle 22 has an introduction hole 38 formed therein.

In FIGS. 8A and 8B, the support portion 56 extends linearly and is inserted into the lumen 22a of the inner needle 22. In FIGS. The closing portion 26 is integrally provided at the distal end portion of the support portion 56 . In other words, the closure part 26 and the support part 56 are integrally molded. However, the closing portion 26 may be joined to the supporting portion 56 by caulking, fitting, adhesion, or the like. The closing part 26 is provided so as to be bent with respect to the support part 56.

As shown in FIG. 8B, when viewed from the axial direction of the inner needle 22, the occupation rate of the support portion 56 with respect to the inner cavity 22a of the inner needle 22 is preferably 40% or less, more preferably 30% or less, and approximately 20%. More preferred. The cross section of the support portion 56 is formed into a circular shape. However, the cross section of the support portion 56 may be polygonal (for example, quadrangular) or annular (circular, quadrangular, etc.). Further, the support portion 56 may be formed in a plate shape. A base end portion of the support portion 56 is fixed to the inner surface of the fixing member 58 (see FIG. 7).

According to the catheter assembly 10 including the needle member 14B, similarly to the needle member 14 described above, it is possible to confirm that the inner needle 22 secures the blood vessel, and to prevent the inner needle 22 from penetrating the rear wall 104 of the blood vessel 102. You can know with good accuracy.

Further, the catheter assembly 10 including the needle member 14B has the following effects.

The needle member 14B includes a needle hub 50 fixed to the proximal end of the inner needle 22, and a support portion 56 that passes through the lumen 22a of the inner needle 22 and is fixed to the needle hub 50. is provided at the tip of the support portion 56.

According to such a configuration, the configuration of the needle member 14B can be simplified.

The occlusion part 26 is not joined to the inner needle 22

According to such a configuration, there is no need to join the closing portion 26 to the inner needle 22, so that the manufacturing cost of the needle member 14B can be reduced.

The closing part 26 is provided so as to be bent with respect to the support part 56.

According to such a configuration, the cross-sectional area of the support portion 56 can be made relatively small.

When viewed from the axial direction of the inner needle 22, the occupancy rate of the support portion 56 with respect to the lumen 22a of the inner needle 22 is 40% or less.

According to such a configuration, blood can be smoothly circulated through the lumen 22a of the inner needle 22.

The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the gist of the present invention.

In the needle member 14B, the needle member 14B may have a closing portion 42 and an introduction hole 44 instead of the closing portion 26 and the introduction hole 38.

The above embodiments can be summarized as follows.

The above embodiment is a catheter assembly (10) that includes a tubular inner needle (22) and a tubular catheter shaft (16) through which the inner needle is inserted, the tip of the inner needle being inserted into the catheter assembly (10). A blade surface (28) is formed that is inclined with respect to the axis of the inner needle, and the blade surface has a cutting edge (28a) located at the most distal end of the inner needle, and a proximal end of the blade surface in the axial direction. The catheter assembly has a blade base (28b) located on the blade surface, and the catheter assembly has a closing part (26, 42) that closes at least the blade base side of the tip opening (22b) of the inner needle formed on the blade surface. ), an introduction hole (38, 44) for guiding blood into the lumen (22a) of the inner needle is formed on the tip side of the inner needle than the blade, and the axis of the inner needle is The catheter assembly is disclosed, in which the proximal ends (P1, P4) of the introduction hole are located more distally than the proximal ends (P2, P5) of the distal opening of the inner needle.

In the above catheter assembly, the introduction hole may be located on the distal end side of the blade surface.

In the above catheter assembly, the occluding portion does not block a distal end portion of the distal opening of the inner needle, and the introduction hole is a portion of the distal opening of the inner needle that is not obstructed by the occluding portion. may be formed by.

In the above catheter assembly, the introduction hole may be positioned offset from the blade surface in the circumferential direction of the inner needle.

In the catheter assembly described above, the introduction hole may be positioned deviated by 180° in the circumferential direction of the inner needle with respect to a center line (L) connecting the cutting edge and the cutting base.

In the above catheter assembly, the proximal end of the introduction hole may be located on the distal side of the center (P3, P6) of the distal opening of the inner needle in the axial direction of the inner needle.

In the above catheter assembly, the closing portion may completely close the tip opening of the inner needle.

In the above catheter assembly, one or more introduction holes may be provided.

In the above catheter assembly, the occluding portion may be joined to the inner needle.

The above catheter assembly includes a needle hub (50) fixed to the proximal end of the inner needle, and a support part (56) inserted through the inner lumen of the inner needle and fixed to the needle hub. The closing portion may be provided at a distal end portion of the supporting portion.

In the above catheter assembly, the occluding portion may not be joined to the inner needle.

In the above catheter assembly, the occluding portion may be provided to be bent relative to the supporting portion.

In the above catheter assembly, the support portion may occupy 40% or less of the lumen of the inner needle when viewed from the axial direction of the inner needle.

10...Catheter assembly 16...Catheter shaft 22...Inner needle 22b...Tip opening 24, 50...Needle hub 26, 42...Occluded part 28...Blade surface 28a...Blade tip 28b...Blade base 38, 44...Introduction hole 56...Support part

Claims (11)

A catheter assembly comprising a tubular inner needle and a tubular catheter shaft through which the inner needle is inserted,
a needle hub fixed to the proximal end of the inner needle;
a support part inserted through the inner lumen of the inner needle and fixed to the needle hub;
The tip of the inner needle is formed with a blade surface that is inclined with respect to the axis of the inner needle,
The blade surface is
a cutting edge located at the leading edge of the inner needle;
a blade base located at the base end of the blade surface in the axial direction,
The catheter assembly includes a closing portion formed on the blade surface that closes at least the blade side of the tip opening of the inner needle,
An introduction hole for guiding blood into the lumen of the inner needle is formed on the tip side of the inner needle than the blade,
In the axial direction of the inner needle, the proximal end of the introduction hole is located on the distal side of the proximal end of the distal opening of the inner needle,
The catheter assembly, wherein the occlusion part is provided at a distal end of the support part. The catheter assembly of claim 1, comprising:
The introduction hole is located on the distal side of the blade surface. 3. The catheter assembly of claim 2, comprising:
The closing part does not block the tip of the tip opening of the inner needle,
In the catheter assembly, the introduction hole is formed by a portion of the tip opening of the inner needle that is not blocked by the blocking portion. The catheter assembly of claim 1, comprising:
In the catheter assembly, the introduction hole is positioned offset from the blade surface in a circumferential direction of the inner needle. 5. The catheter assembly of claim 4,
In the catheter assembly, the introduction hole is positioned 180° in a circumferential direction of the inner needle with respect to a center line connecting the blade tip and the blade base. The catheter assembly according to claim 4 or 5,
In the axial direction of the inner needle, the proximal end of the introduction hole is located on the distal side of the center of the distal opening of the inner needle. The catheter assembly according to any one of claims 4 to 6,
The catheter assembly, wherein the closing portion completely closes a distal end opening of the inner needle. A catheter assembly according to any one of claims 1 to 7, comprising:
The catheter assembly includes one or more introduction holes. A catheter assembly according to any one of claims 1 to 8 , comprising:
The catheter assembly, wherein the occlusion portion is not joined to the inner needle. A catheter assembly according to any one of claims 1 to 9 , comprising:
The catheter assembly, wherein the occlusion section is provided to be bent relative to the support section. A catheter assembly according to any one of claims 1 to 10 , comprising:
The catheter assembly, wherein the support portion occupies 40% or less of the inner lumen of the inner needle when viewed from the axial direction of the inner needle.

Images