JP2005230308A - Puncture device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a puncture device which is excellent in puncturing property to a living body and with which a blood vessel is secured easily and reliably and securing of the blood vessel is confirmed speedily. <P>SOLUTION: The puncture device 1 comprises: a hollow outer needle 2; an outer needle hub 3 provided at its proximal end; a hollow inner needle 4 used by being inserted into the outer needle 2; and an inner needle hub 5 provided at its proximal end. The outer needle 2 has a reduced diameter part 23, an outer diameter fixed part 21 where an outer diameter is nearly fixed, and a tapered part 22 where the outer diameter is gradually increased toward a proximal end from the side of the distal end. The inner needle 4: a sharp needle tip 41; a small diameter part 42 where the outer diameter is nearly fixed; an intermediate part 43 consisting of a tapered part where the outer diameter is gradually increased toward the proximal end; and a large diameter part 44 where the inner diameter and the outer diameter are respectively larger than those of the small diameter part 42 from the side of the distal end. In a state where the puncture device 1 is assembled, the needle tip 41 projects most from the distal end opening 24 of the outer needle 2, and the proximal end of the small diameter part 42 and the distal end of the large diameter part 44 are positioned inside the outer needle 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a puncture device.

  For example, a treatment for inserting a catheter such as a balloon catheter or a guiding catheter or a lead wire of a cardiac pacemaker into a blood vessel is an indwelling needle assembly including an outer needle and an inner needle inserted through the outer needle (for example, Patent Document 1). And a sheath introducer including a sheath and a dilator inserted into the sheath.

  In general, an indwelling needle assembly is punctured into a blood vessel such as a femoral artery with the outer needle and inner needle assembled (the needle tip of the inner needle protrudes from the tip of the outer needle), and then the outer needle Remove the inner needle from the inner needle and leave only the outer needle in place. Pass the guide wire through the outer needle into the blood vessel. Insert the sheath introducer with the sheath and dilator assembled into the guide wire. And proceed to a predetermined position. Thereafter, when the dilator and the guide wire are pulled out, the sheath is left in place, and the inside of the blood vessel can be directly accessed from outside the patient's body through the sheath. Thereby, various catheters and lead wires for cardiac pacemakers can be introduced into the blood vessel via the sheath.

  By the way, the indwelling needle assembly (puncture device) as described above is required to have little damage to the blood vessel at the time of puncture, low puncture resistance, and easy to secure the blood vessel. The outer needle is preferably as thin as possible (having a small outer diameter).

  However, when the needle tube is thinned, the strength is lowered and the needle tube is easily bent, and the puncture property (easy to reach the target portion of the living body of the needle tip) is lowered. That is, the needle tube may be deformed by resistance of skin, subcutaneous fat, muscle tissue, or the like, and the needle tip may not reach the target blood vessel. In particular, when puncturing an artery present at a deep position in a living body, such a defect appears remarkably or frequently.

  In addition, the fact that the needle tip of the inner needle has secured the blood vessel can be visually confirmed by inflow (flashback) of blood into the inner needle hub installed at the proximal end of the inner needle. As a result, the inner diameter of the inner needle also becomes smaller, so that the time difference from when the needle tip is actually punctured to the blood vessel until the flashback is confirmed becomes large, and it may not be possible to accurately and quickly know how to secure the blood vessel. There is.

  Normally, when the flashback is confirmed, the inner needle and outer needle are slightly advanced (the inner needle and outer needle are advanced by a slight distance based on the operator's feelings and experience), so that the tip of the outer needle However, if the flashback is slow as described above, the operation of advancing the inner needle and the outer needle by a fine distance also has an adverse effect. For example, the inner needle is punctured too deeply. There is a risk of damaging the other side of the blood vessel with a needle or skewing the blood vessel.

Japanese Patent Laid-Open No. 2001-112871

  An object of the present invention is to provide a puncture device that is excellent in puncture ability to a living body, can ensure a blood vessel easily and reliably, and can quickly confirm that a blood vessel has been secured.

Such an object is achieved by the present inventions (1) to (14) below.
(1) A hollow outer needle, an outer needle hub provided at a proximal end portion of the outer needle, having a lumen portion communicating with the inside of the outer needle, and a sharp needle inserted into the outer needle and having a sharp tip A puncture device comprising a hollow inner needle having a tip and an inner needle hub provided at a proximal end portion of the inner needle and having a lumen portion communicating with the inside of the inner needle,
The inner needle is located in the vicinity of the needle tip, and has a small-diameter portion whose outer diameter is substantially constant, and a large-diameter portion that is located on the proximal end side and has a larger outer diameter than the small-diameter portion,
The distal end of the large-diameter portion is located in the outer needle with the inner needle inserted into the lumen of the outer needle and the needle tip most protruded from the distal end opening of the outer needle. A puncture device.

  (2) The puncture device according to (1), wherein an inner diameter of the large diameter portion is larger than an inner diameter of the small diameter portion.

  (3) The puncture device according to (1) or (2), wherein the inner needle has an intermediate portion that relaxes a change in outer diameter between the small diameter portion and the large diameter portion.

  (4) The puncture device according to (3), wherein the intermediate portion is configured by a tapered portion whose outer diameter gradually increases toward the proximal direction.

  (5) With the inner needle inserted into the lumen of the outer needle and the needle tip most protruded from the distal end opening of the outer needle, the proximal end of the small diameter portion is positioned in the outer needle. The puncture device according to any one of (1) to (4) above.

  (6) The outer needle includes a portion having a substantially constant outer diameter and a tapered portion that is located on the proximal end side and gradually increases in the outer diameter toward the proximal end. ) The puncture device according to any one of the above.

  (7) The puncture device according to any one of (1) to (6), wherein the outer needle has a reduced diameter portion whose outer diameter decreases toward the distal end at the distal end.

  (8) The inner diameter of the distal end of the outer needle is substantially equal to the outer diameter of the small diameter portion of the inner needle or smaller than the outer diameter of the small diameter portion of the inner needle. The puncture device according to 1.

(9) The inner needle hub can be engaged with the proximal end side of the outer needle hub,
A state in which the inner needle is inserted into a lumen of the outer needle, the needle tip protrudes most from a distal end opening of the outer needle, with the inner needle hub engaged with a proximal end side of the outer needle hub; The puncture device according to any one of (1) to (8) above.

  (10) The puncture device according to any one of (1) to (9), wherein the outer needle and the outer needle hub are integrally formed of the same material.

  (11) The puncture device according to any one of (1) to (10), wherein the outer needle is configured to be divided into a plurality along the longitudinal direction.

(12) When the outer diameter (average) of the small diameter portion of the inner needle is D ₁ and the outer diameter (average) of the large diameter portion is D ₂ , the outer diameter ratio D ₁ / D ₂ is 0.25. The puncture device according to any one of (1) to (11) above, which is ˜0.95.

(13) When the inner diameter (average) of the small diameter portion of the inner needle is d ₁ and the inner diameter (average) of the large diameter portion is d ₂ , the outer diameter ratio d ₁ / d ₂ is 0.2-0. The puncture device according to any one of the above (1) to (12), which is .9.

  (14) The puncture device according to any one of (1) to (13), which is for introducing a sheath introducer.

  According to the present invention, puncture resistance is low, sufficient strength is ensured without bending of the needle due to resistance during puncture, and excellent puncture properties for a living body. In addition, the blood vessel can be secured easily and reliably, and the fact that the blood vessel has been secured can be quickly and reliably grasped by flashback.

  Hereinafter, the puncture device of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

(First embodiment)
FIG. 1 is a longitudinal sectional view showing a first embodiment of the puncture device of the present invention, and FIG. 2 is a plan view showing a configuration in the vicinity of the distal end portion of the inner needle in the puncture device shown in FIG. In the following description, the right side in FIGS. 1 and 2 is referred to as “base end” and the left side is referred to as “tip”.

  As shown in FIG. 1, a puncture device (indwelling needle assembly) 1 according to the present invention is used by being inserted into a hollow outer needle 2 that is an indwelling needle (introducing needle) and the outer needle 2 at the tip. A hollow inner needle 4 having a sharp needle tip 41.

  An outer needle hub 3 is integrally formed of the same material as the outer needle 2 at the proximal end portion of the outer needle 2. As a result, the number of parts is small and the manufacture is easy, and the outer needle hub 3 and the outer needle 2 can be formed on a smooth surface without a step, and the guide wire is inserted into the outer needle 2. There is an advantage that it can be inserted smoothly. Further, the inside (internal space) 31 of the outer needle hub 3 communicates with the lumen of the outer needle 2.

  The outer needle 2 has an outer diameter constant portion 21 whose outer diameter is substantially constant, and a tapered portion 22 that is located on the proximal end side and has an outer diameter gradually increasing toward the proximal end. Furthermore, the outer needle 2 has a reduced diameter portion 23 whose outer diameter decreases (gradually decreases) toward the distal end at the distal end thereof (on the distal end side of the constant outer diameter portion 21). By adopting such a configuration, it is possible to easily puncture a living body without impairing the puncture property (operability), and in particular, it is possible to reduce the puncture wound of a blood vessel and the puncture resistance is small. The effect that the invasion at the time of puncture can be reduced is exhibited. Further, by having the tapered portion 22, the outer needle 2 is secured with sufficient strength (strength of stiffness), and is prevented from being unintentionally curved and bent. Furthermore, there is an effect that the insertion property of the sheath introducer can be improved by expanding the puncture portion with the taper portion 22.

  The inner diameter of the distal end of the reduced diameter portion 23 (the distal end of the outer needle 2) is substantially equal to the outer diameter of the small diameter portion 42 of the inner needle 4 described later or slightly smaller than the outer diameter of the small diameter portion 42 of the inner needle 4. As a result, the inner needle 4 is inserted into the lumen of the outer needle 2 and the needle tip 41 is protruded most from the distal end opening 24 of the outer needle 2 (hereinafter, this state is referred to as an “assembled state”). Since the inner peripheral surface at the tip of the diameter portion 23 is in close contact with the outer peripheral surface of the small diameter portion 42 of the inner needle 4, the step difference from the outer surface of the inner needle 4 can be minimized. In this case, the level difference between the outermost surface of the reduced diameter portion 23 and the outer surface of the inner needle 4 is preferably 0.05 mm or less, and more preferably 0.01 mm or less. With such a configuration, when the living body is punctured with the puncture device 1 in the assembled state, the puncture wound can be reduced, the puncture resistance is small, and the invasion to the living body can be further reduced.

  The taper angle of the tapered portion 22 of the outer needle 2 (the angle of the outer surface with respect to the central axis of the outer needle 2) is not particularly limited, but is preferably about 5 to 60 °, and more preferably about 15 to 25 °. By setting such a taper angle, a sufficient strength can be secured in the taper portion 22 and the living tissue can be spread with a small piercing resistance.

  Moreover, it is preferable that the outer diameter and inner diameter of the front-end | tip of the taper part 22 are substantially equal to the outer diameter and inner diameter of the base end of the outer diameter fixed part 21, respectively. As a result, the outer surface of the boundary portion between the tapered portion 22 and the constant outer diameter portion 21 is a smooth surface without a step, so that the living tissue such as the epidermis can be spread while suppressing the piercing resistance of the outer needle 2 to be small. Can do.

  Further, since the inner surface of the boundary portion between the tapered portion 22 and the constant outer diameter portion 21 is also a smooth surface without a step, when the guide wire is inserted into the outer needle 2, it can be smoothly inserted without being caught. it can.

  Moreover, it is preferable that the outer diameter and inner diameter of the base end of the taper part 22 are substantially equal to the outer diameter and inner diameter of the distal end of the outer needle hub 3, respectively. As a result, the inner surface of the boundary portion between the tapered portion 22 and the outer needle hub 3 becomes a smooth surface without a step, so that when the guide wire is inserted into the outer needle 2, it can be smoothly inserted without being caught. it can.

  By providing the outer needle 2 with the tapered portion 22 as described above, when the outer needle 2 is punctured into the living body, the tapered portion 22 exerts a function of expanding living tissue such as the epidermis, and as a result, the sheath The effect that the insertion resistance at the time of inserting the introducer is reduced is obtained.

  The length of the outer diameter constant portion 21 is not particularly limited, but is preferably about 5 to 100 mm, and more preferably about 15 to 60 mm.

  The outer diameter (average) of the constant outer diameter portion 21 is not particularly limited, but is preferably about 0.6 to 2.2 mm, and more preferably about 1.0 to 1.8 mm.

  The wall thickness of the tube of the constant outer diameter portion 21 is not particularly limited, but is preferably about 0.05 to 0.30 mm in order not to hinder the diameter reduction of the outer needle 2 while ensuring sufficient strength. About 10 to 0.20 mm is more preferable.

  Although the length of the taper part 22 is not specifically limited, About 3-50 mm is preferable and about 5-10 mm is more preferable.

  The maximum outer diameter of the tapered portion 22 (the outer diameter of the proximal end portion of the tapered portion 22) is not particularly limited, but is preferably about 4.0 to 8.0 mm, and more preferably about 5.0 to 6.0 mm.

  The wall thickness of the tube of the taper portion 22 is not particularly limited, but is preferably about 0.2 to 2.0 mm in order not to hinder the diameter reduction of the outer needle 2 while securing sufficient strength. About 1.0 mm is more preferable.

  Although the length of the reduced diameter part 23 is not specifically limited, About 0.2-30 mm is preferable and about 1-10 mm is more preferable.

  The wall thickness of the tube in the vicinity of the distal end of the reduced diameter portion 23 is preferably 0.05 mm or less in order to reduce the step with the outer surface of the inner needle 4, and is about 0.01 to 0.001 mm. Is more preferable.

  The constituent material of the outer needle 2 is not particularly limited. For example, polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene copolymer (ETFE), polyfluorinated ethylene propylene (FEP), polyperfluoroalkoxy fluoride resin Fluorine resins such as (PFA) and polyvinylidene fluoride (PVDF), polyolefins such as polyethylene, polypropylene, and polybutylene, and various resins such as polyamide, polyester, polyurethane, and polyether nylon resin are preferable. Further, an X-ray contrast agent such as barium sulfate or barium carbonate may be blended in the constituent material of the outer needle 2 to provide a contrast function.

  Such an outer needle 2 can be manufactured, for example, by methods such as injection molding, extrusion molding, blow molding, and heat stretching.

  Moreover, it is preferable that the outer needle 2 is configured so as to be divided into a plurality of pieces (for example, divided into two) along the longitudinal direction. Thereby, the outer needle 2 can be easily removed while the medical instrument is left in the body by dividing and removing the outer needle 2 with a medical instrument such as a guide wire inserted into the outer needle 2. Can do.

  As a configuration for enabling the outer needle 2 to be divided, it is possible to provide a fragile portion (not shown) including two or more grooves along the longitudinal direction of the outer needle 2.

  As shown in FIG. 1, an inner needle hub (housing) 5 composed of a substantially cylindrical member is fixed to a proximal end portion of the inner needle 4 in a liquid-tight manner. The inside (internal space) 52 of the inner needle hub 5 communicates with the lumen of the inner needle 4. The inner needle hub 5 is preferably made of a transparent or translucent resin, and the visibility of the interior 52 is ensured. Thereby, it can be visually confirmed by flashback that the needle tip 41 has secured the blood vessel.

  An engagement portion (fitting portion) 51 having a reduced diameter is formed at the distal end portion of the inner needle hub 5, and this engagement portion 51 engages with the proximal end portion of the outer needle hub 3 in the assembled state ( (See FIG. 1). Thus, in the assembled state in which the outer needle hub 3 and the inner needle hub 5 are engaged, the needle tip 41 of the inner needle 4 is in the state of most protruding from the distal end opening 24 of the outer needle 2.

  At the outer peripheral portion on the distal end side of the inner needle hub 5, a flange-like (hook-like) finger contact portion 53 is formed.

  Further, a ventilation filter (not shown) that allows gas to pass but not liquid to pass through may be attached to the proximal end portion of the inner needle hub 5 so as to seal the proximal end opening of the inner needle hub 5. . As a result, blood that has flowed into the interior 52 of the inner needle hub 5 through the inner needle 4 is prevented from leaking out from the proximal end opening of the inner needle hub 5. Moreover, since the ventilation filter has sufficient air permeability before coming into contact with blood, the time required for flashback can be shortened.

  Specific examples of such a ventilation filter include various sintered porous bodies, hydrophobic nonwoven fabrics, and other porous bodies. In this case, as the sintered porous body, for example, a material obtained by sintering a material containing a polymer material (powder) such as polyethylene and a hydrophilic (water-soluble, water-swellable) polymer is preferable. When this sintered porous body is used, aeration is blocked by contact with the liquid (blood), so that intrusion of air from the outside can be prevented.

  The inner needle 4 is made of, for example, a metal material such as stainless steel, aluminum or an aluminum alloy, titanium or a titanium alloy, and a sharp needle tip 41 is formed at the tip thereof. The needle tip 41 has a pair of blade surfaces 411 inclined at a predetermined angle with respect to the axis of the inner needle 4 (see FIG. 2).

  As shown in FIGS. 1 and 2, the inner needle 4 is located in the vicinity of the proximal end of the needle tip 41, and has a small diameter portion 42 whose outer diameter is substantially constant, and a proximal end side of the small diameter portion 42. A large-diameter portion 44 having an inner diameter and an outer diameter larger than those of 42. Further, the inner needle 4 has an intermediate portion 43 between the small diameter portion 42 and the large diameter portion 44 to alleviate changes in the outer diameter (outer diameter difference). The intermediate portion 43 is configured by a tapered portion whose outer diameter gradually increases toward the proximal direction.

  By adopting such a configuration, it is possible to easily puncture a living body without impairing the puncture property (operability), and in particular, it is possible to reduce the puncture wound of a blood vessel and the puncture resistance is small. Invasion at the time of puncture can be reduced. In addition, the risk of damage to blood vessels, nerves, muscles and other tissues other than the puncture wound is also reduced. Since the inner diameter is enlarged from the middle by the large diameter portion 44, the blood flow in the inner needle 4 is promoted, and the time required for flashback (the blood flowing from the needle tip 41 reaches the inner needle hub 5). Time) and the needle tip 41 can quickly and reliably know that the blood vessel has been secured. In addition, by having the large diameter portion 44, the inner needle 4 is secured with sufficient strength (strength strength), and is prevented from being bent and bent unintentionally at the time of puncture or the like.

  The large-diameter portion 44 may have a substantially constant outer diameter over its entire length, or may have a tapered portion where the outer diameter slightly increases in the proximal direction at least in a part of the longitudinal direction. . Alternatively, it may be a multistage shape having two or more portions having different outer diameters.

  As shown in FIG. 1, the intermediate portion (tapered portion) 43 of the inner needle 4 is located in the outer needle 2 in the assembled state. That is, the distal end of the large diameter portion 44 of the inner needle 4 is located in the outer needle 4, and the proximal end of the small diameter portion 42 on the distal end side of the large diameter portion 44 is also located in the outer needle 4. By adopting such a configuration, the intermediate portion (tapered portion) 43 of the inner needle 4 is not caught by a living tissue such as the epidermis, and thus the effect that the piercing resistance becomes smaller is exhibited.

The length _{L 1} of the needle point 41 is not particularly limited, preferably about 0.5 to 5.0 mm, about 1.0~3.5mm is more preferable.

The length _{L 2} of the small diameter portion 42 is not particularly limited, preferably about 1 to 30 mm, about 2~15mm is more preferable.

Outer diameter (average) _{D 1} of the small diameter portion 42 is not particularly limited, preferably about 0.25～1.7Mm, about 0.5~1.0mm is more preferable.

The inner diameter (average) d ₁ of the small diameter portion 42 is not particularly limited, but is preferably about 0.1 to 1.5 mm, and more preferably about 0.3 to 0.6 mm.

The length _{L 3} of the tapered portion 43 is not particularly limited, preferably about 0.5 to 10 mm, about 1~3.5mm is more preferable.

The length _{L 4} of the large diameter portion 44 is not particularly limited, preferably about 10 to 200 mm, about 25~80mm is more preferable.

Outer diameter (average) _{D 2} of the large-diameter portion 44 is not particularly limited, preferably about 0.4 to 2.0 mm, about 0.6~1.3mm is more preferable.

Inside diameter (average) _{d 2} of the large-diameter portion 44 is not particularly limited, preferably about 0.2～1.8Mm, about 0.4~1.1mm is more preferable.

  When the dimensions are as described above, the balance between the strength of the inner needle 4 and the puncture property is good, and in particular, the inner needle 4 does not lose its bending resistance and does not bend. It becomes.

The outer diameter ratio _D 1 / _{D 2} is preferably in the range of about .25 to .95, more preferably about 0.5 to 0.8. By setting the outer diameter ratio in such a range, it is possible to obtain better puncture properties while ensuring sufficient strength for the inner needle 4.

Further, the inner diameter ratio d ₁ / d ₂ is preferably about 0.2 to 0.9, and more preferably about 0.5 to 0.8. By setting the inner diameter ratio in such a range, the time required for flashback can be further shortened while ensuring sufficient strength and good puncture properties for the inner needle 4.

  The manufacture of such an inner needle 4 is, for example, a method of appropriately combining one or more of plastic processing such as press processing, swaging processing, drawing processing, grinding processing, polishing processing, laser processing, etching processing, etc. Can be performed.

  Examples of the constituent material of the inner needle hub 5 include polyolefins such as polyethylene, polypropylene, and ethylene-vinyl acetate copolymer, polyesters such as polyvinyl chloride, polymethyl methacrylate, polycarbonate, polybutadiene, polyamide, polyethylene terephthalate, and polybutylene terephthalate. , Acrylic resins, ABS resins, ionomers, polyacetals, polyphenylene sulfides, polyether ether ketones, and the like.

Next, an example of a usage method (action) of the puncture device 1 will be described.
[1] As shown in FIG. 1, the outer needle 2 and the inner needle 4 are assembled in advance. In such an assembled state of the puncture device 1, the needle tip 41 protrudes most from the distal end opening 24 of the outer needle 2, and the proximal end of the small diameter portion 42 and the distal end of the large diameter portion 44 are housed inside the outer needle 2. ing.

  [2] The assembled inner needle 4 and outer needle 2 are percutaneously punctured into a patient's blood vessel (vein or artery).

  When the needle tip 41 of the inner needle 4 is punctured into the blood vessel, blood flows from the opening of the needle tip 41 due to the internal pressure (blood pressure) of the blood vessel, and flows backward in the inner needle 4 in the proximal direction. The flashback can be visually recognized at the hub 5 introduced into the interior 52 and having visibility. Thereby, it can be known that the needle tip 41 of the inner needle 4 has secured the blood vessel.

  [3] When the inner needle hub 5 is fixed by applying a finger to the finger contact portion 53 and the outer needle hub 3 and the outer needle 2 are advanced by a minute distance in the distal direction, the distal end of the outer needle 2 is inserted into the blood vessel. Thereby, the front-end | tip part of the outer needle 2 ensures a blood vessel.

  [4] With the outer needle 2 in place, the inner needle hub 5 is pulled in the proximal direction, and the inner needle 4 is removed from the outer needle 2.

  [5] A guide wire (not shown) is inserted into the indwelling outer needle 2 from the proximal end opening of the outer needle hub 3. When the distal end side of the guide wire reaches the inside of the blood vessel, the outer needle 2 is removed.

  [6] A sheath introducer in which a dilator is inserted into the sheath is prepared, and the sheath introducer is inserted into the living body through the guide wire. When the distal end portion of the sheath introducer is introduced into the blood vessel, the guide wire and the dilator are removed, and the sheath is left (detained), and the blood vessel is secured by the sheath.

  [7] Leads for various catheters and cardiac pacemakers, for example, are introduced into the blood vessel through the indwelling sheath.

  The use and usage of the puncture device 1 of the present invention are not limited to the above. For example, after the step [4], an infusion line is connected to the outer needle hub 3 via a connector, An infusion solution may be supplied and administered to the patient.

(Second Embodiment)
FIG. 3 is a longitudinal sectional view showing a second embodiment of the puncture device of the present invention.

  Hereinafter, the second embodiment of the puncture device of the present invention will be described with reference to this figure, but the description will focus on the differences from the first embodiment described above, and the description of the same matters will be omitted.

  The puncture device of the present embodiment is the same as that of the first embodiment except that the outer needle hub 3 made of a different material is fixed to the proximal end portion of the outer needle 2 in a liquid-tight manner.

  In other words, in the present embodiment, the outer needle hub 3 composed of a substantially cylindrical member is fixed to the proximal end portion of the outer needle 2 in a liquid-tight manner. An interior (internal space) 31 of the outer needle hub 3 communicates with a lumen of the outer needle 2. The outer needle hub 3 is preferably made of a transparent or translucent resin, and the visibility of the inside 31 is ensured.

  The proximal end portion of the tapered portion 22 of the outer needle 2 is fixed to the distal end portion of the outer needle hub 3 by, for example, fusion or adhesion.

  Examples of the constituent material of the outer needle hub 3 include polyolefins such as polyethylene, polypropylene, and ethylene-vinyl acetate copolymer, polyesters such as polyvinyl chloride, polymethyl methacrylate, polycarbonate, polybutadiene, polyamide, polyethylene terephthalate, and polybutylene terephthalate. , Acrylic resins, ABS resins, ionomers, polyacetals, polyphenylene sulfides, polyether ether ketones, and the like.

  As mentioned above, although the puncture device of this invention was demonstrated about embodiment of illustration, this invention is not limited to this, Each member which comprises a puncture device is arbitrary structures which can exhibit the same function. Can be substituted, and an arbitrary configuration may be added.

It is a longitudinal cross-sectional view which shows 1st Embodiment of the puncture device of this invention. It is a top view which shows the structure of the front-end | tip part vicinity of the inner needle in the puncture device shown in FIG. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the puncture device of this invention.

Explanation of symbols

1 Puncture device 2 Outer needle (Indwelling needle)
21 outer diameter constant portion 22 taper portion 23 reduced diameter portion 24 tip opening 3 outer needle hub 31 inner 4 inner needle 41 needle tip 411 blade surface 42 small diameter portion 43 intermediate portion 44 large diameter portion 5 inner needle hub 51 engaging portion (fit) Joint)
52 inside 53 finger pad

Claims (14)

A hollow outer needle, an outer needle hub provided at a proximal end portion of the outer needle, having a lumen portion communicating with the inside of the outer needle, and inserted into the outer needle and having a sharp needle tip at the tip A puncture device comprising a hollow inner needle and an inner needle hub provided at a proximal end portion of the inner needle and having a lumen portion communicating with the inside of the inner needle,
The inner needle is located in the vicinity of the needle tip, and has a small-diameter portion whose outer diameter is substantially constant, and a large-diameter portion that is located on the proximal end side and has a larger outer diameter than the small-diameter portion,
The distal end of the large-diameter portion is located in the outer needle with the inner needle inserted into the lumen of the outer needle and the needle tip most protruded from the distal end opening of the outer needle. A puncture device.   The puncture device according to claim 1, wherein an inner diameter of the large diameter portion is larger than an inner diameter of the small diameter portion.   The puncture device according to claim 1 or 2, wherein the inner needle has an intermediate portion between the small-diameter portion and the large-diameter portion that relaxes changes in the outer diameter thereof.   The puncture device according to claim 3, wherein the intermediate portion is configured by a tapered portion having an outer diameter gradually increasing toward a proximal direction.   The proximal end of the small-diameter portion is located in the outer needle with the inner needle inserted into the lumen of the outer needle and the needle tip protruding most from the distal end opening of the outer needle. The puncture device according to any one of 1 to 4.   The said outer needle has a site | part with the substantially constant outer diameter, and a taper part which is located in the base end side from it and the outer diameter increases gradually toward the base end direction. Puncture tool.   The puncture device according to any one of claims 1 to 6, wherein the outer needle has a reduced-diameter portion whose outer diameter decreases in a distal direction at a distal end portion thereof.   The puncture device according to any one of claims 1 to 7, wherein an inner diameter of a tip of the outer needle is substantially equal to an outer diameter of the small diameter portion of the inner needle or smaller than an outer diameter of the small diameter portion of the inner needle. The inner needle hub can be engaged with the proximal end side of the outer needle hub,
A state in which the inner needle is inserted into a lumen of the outer needle, the needle tip protrudes most from a distal end opening of the outer needle, with the inner needle hub engaged with a proximal end side of the outer needle hub; The puncture device according to any one of claims 1 to 8.   The puncture device according to any one of claims 1 to 9, wherein the outer needle and the outer needle hub are integrally formed of the same material.   The puncture device according to any one of claims 1 to 10, wherein the outer needle is configured to be divided into a plurality of parts along a longitudinal direction. When the outer diameter (average) of the small diameter portion of the inner needle is D ₁ and the outer diameter (average) of the large diameter portion is D ₂ , the outer diameter ratio D ₁ / D ₂ is 0.25-0. The puncture device according to any one of claims 1 to 11, which is 95. When the inner diameter (average) of the small diameter portion of the inner needle is d ₁ and the inner diameter (average) of the large diameter portion is d ₂ , the outer diameter ratio d ₁ / d ₂ is 0.2 to 0.9. The puncture device according to any one of claims 1 to 12.   The puncture device according to any one of claims 1 to 13, which is for introducing a sheath introducer.

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