JP2013111109A - Puncture needle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the distal end of a dull needle from pressurizing a blood vessel wall over an incisure, and to smoothly advance the distal end part of the dull needle to the back of a puncture opening without strongly pressuring the edge of the puncture opening caused by the distal end part of the dull needle once inserted into the puncture opening.SOLUTION: The dull needle 10 is inserted into a puncture route from the skin to a hypodermic shunt blood vessel, and is punctured to the shunt blood vessel. The dull needle 10 has an inclined end face 20a inclined with respect to the axis A of the needle, a projection plate 21 is projected from the distal end part 20b of the inclined end face 20a, and then the distal end part 21a of the projection plate 21 is formed in a circular arcuate edge. When the dull needle 10 is viewed from above while the dull needle 10 horizontally stands still and the inclined end face 20a and the projection plate 21 direct upwards, side edges 20c and 21c at left and right distal end parts following the circular arcuate distal end part 21a are each straight.

Description

  The present invention relates to a puncture needle that is inserted into a puncture route formed from the skin surface to the surface of a shunt blood vessel and inserted into the shunt blood vessel through a puncture hole formed on the surface of the shunt blood vessel.

  When blood purification such as hemodialysis is performed, two puncture needles having sharp tips are used to puncture shunt blood vessels at different sites from the skin surface through the subcutaneous tissue, and one of the puncture needles. The blood is removed from the shunt blood vessel through the blood, and the removed blood is purified in a blood purifier, and then the purified blood is returned to the shunt blood vessel through the other puncture needle.

  These punctures need to be performed every time when blood is purified, but each time they give great pain to the patient. Therefore, in recent years, a so-called buttonhole puncture method has been used to reduce pain during puncture (see Patent Document 1 and Non-Patent Document 2). In the buttonhole puncture method, for example, as shown in FIG. 12, at the first puncture, a normal puncture needle 100 with high sharpness is used to penetrate the subcutaneous tissue 101 from the skin 102 to the surface 104 of the shunt blood vessel 103. 105 is produced. Thereby, on the surface 104 of the shunt blood vessel 103 and on the extended line of the puncture route 105, an arc-shaped cut projecting backward with respect to the puncture direction X by the normal puncture needle 100, for example, as shown in FIG. A mark 106 is formed. Then, at the time of puncture for blood purification performed thereafter, a puncture needle (hereinafter referred to as “dull needle”) 115 having low sharpness is inserted into the puncture route 105 from the skin-side entrance 105a as shown in FIG. Then, after passing through the puncture route 105, the puncture hole 107 on the surface 104 of the shunt blood vessel 103 formed by the notch 106 is passed through and inserted into the shunt blood vessel 103. According to this method, there is no need to puncture the skin 102 after the puncture route 105 is produced, so that the patient's pain is reduced.

  In the above buttonhole puncture method, the puncture needle 100 used for the first puncture to form the puncture route 105 in the subcutaneous tissue 101 and the notch 106 in the surface 104 of the shunt blood vessel 103 is as shown in FIG. The tip end has an inclined end surface 100a, and a pointed point 100b is formed at the tip end portion of the inclined end surface 100a. When the shunt blood vessel 103 is punctured from the skin 102 with the puncture needle 100, first, as shown in FIG. 12, the slanted end surface 100a of the puncture needle 100 is directed upward, and is inserted into the subcutaneous tissue 101 obliquely from the skin 102. Thereafter, the inclined end surface 100a of the puncture needle 100 is pushed toward the shunt blood vessel 103, and further, after the apex point 100b reaches the surface of the shunt blood vessel 103, the puncture needle 100 is inclined into the shunt blood vessel 103 as it is. The end face 100a is inserted.

JP 2009-045124 A

Shigeki Toma, Takahiro Shinzato, Kenji Maeda et al, A timesaving Method to create a fixed puncture route for the buttonhole technique, Nephrol Dial Transplant, UK, OXFORD university press, 2003, 18: p2118-2121

The notch 106 formed as described above is formed on the surface 104 of the shunt blood vessel 103 in a convex arcuate shape backward with respect to the insertion direction X of the puncture needle 100 as shown in FIG. The area on the shunt blood vessel wall defined by the virtual straight line 106a connecting both ends of the arc-shaped notch 106 and the arc-shaped notch 106 is called a flap. The flap 108 functions as a lid for the puncture hole 107, while the portion that coincides with the virtual straight line 106a functions as a hinge when the flap 108 opens and closes.

In the notch 106 having such a structure, when puncturing with the dull needle 115 having low sharpness after the second time, as shown in FIG. When pushed, the flap 108 rotates with the virtual straight line 106 a as a hinge, thereby opening the puncture hole 107, and as a result, the distal end portion 115 b of the dull needle 115 is inserted into the shunt blood vessel 103.

  As shown in FIG. 17A, a pointed edge line 100c is formed at the tip of a general puncture needle 100, and accordingly, the tip of the puncture needle 100 has a pointed point 100b. Thus, the apex point 100b can penetrate the blood vessel wall. On the other hand, as shown in FIG. 17B, the dull needle 115 has an inclined end surface 115a formed by obliquely cutting a tubular end portion, and the tip end portion 115b of the inclined end surface 115a is elliptical. This is a part of the inclined end face 115a, and is rounded. Therefore, the tip 115b does not pierce the blood vessel wall and does not penetrate the blood vessel wall.

  By the way, at the time of the previous blood purification therapy, as the dull needle 115 is inserted into the shunt blood vessel 103, the puncture hole 107 covered with the flap 108 is opened as shown in FIG. By removing the dull needle 115, the flap 108 covers the puncture hole 107 again, and then the puncture hole 107 is closed by the flap 108 until the start of the next blood purification therapy. During this time, fibrin glue adheres to the notch 106 shown in FIG. 13, and the blood vessel walls on both sides sandwiching the notch 106, that is, the opposite vessel wall 112 sandwiching the notch 106 of the flap 108 flaps. It adheres to 108. Then, in the next blood purification therapy, stress is generated in the notch 106 by pressing the optimum pressing portion 108b of the flap 108 with a strength equal to or higher than the shunt blood vessel pressure with the tip 115b of the dull needle 115, The flap 108 and the blood vessel wall 112 are peeled off by fibrin glue.

  However, when downward pressure greater than the internal pressure of the shunt blood vessel is applied to the flap 108 by the tip 115b of the above-described dull needle 115, the shunt blood vessel walls on both sides of the notch 106 are separated from the notch 106. As shown in FIG. 18, the tip of the round dull needle 115 is recessed into the surface wall of the shunt blood vessel 103 with a length before the sufficiently strong stress is applied.

  At this time, if the portion of the flap 108 pressed by the tip portion 115b of the dull needle 115 is shifted to the left or right from the center of the flap 108, the tip portion of the dull needle 115 may be cut off depending on the degree of the shift. 13, both the flap 108 and the shunt blood vessel wall 112 on the opposite side of the flap 108 shown in FIG. In such a situation, the notch 106 does not generate a stress that is strong enough to separate the vessel walls 108, 112 adhering to the notch 106. The tip 108 a does not rotate into the lumen of the shunt blood vessel 103 and the dull needle 115 is not inserted into the shunt blood vessel 103.

  This phenomenon is the largest cause of buttonhole puncture failure and is called the trampoline effect. And in Japan, which uses 17-18G thick dull needles, 50-70% of patients have abandoned buttonhole puncture due to the trampoline effect, using 14-16G thick dull needles. In Europe, 24% of patients experience a trampoline effect (see Summary of the EDTNA / ERCA Journal Club discussion Autumn 2007).

  In addition, as shown in FIG. 13, the notch 106 formed in an arc shape protruding rearward with respect to the puncture direction X of the puncture needle 100, that is, the insertion direction of the dull needle 115, is rearward with respect to the direction X. In the flap 108 with the tip, the lateral diameter of the puncture hole increases as it goes forward with respect to the insertion direction X of the dull needle 115, so that the blood vessel walls on both sides of the notch 106 where the tip 115b of the dull needle 115 has once adhered are temporarily removed. When pulled apart and inserted into the puncture hole 107, it is inserted into the back of the shunt blood vessel with relative ease thereafter.

  More recently, on the surface 104 of the shunt blood vessel 103 and on the extended line of the puncture route 105, an arc-shaped notch 111 convex forward with respect to the puncture route as shown in FIG. Yes. In order to produce the arc-shaped notch 111 convex forward with respect to the long axis of the puncture route, the first puncture has an inclined end surface 120a as shown in FIG. 20, for example, and the inclined end surface 120a A sharp point 120b is formed at the tip of the needle, and a puncture needle 120 is used in which the point 120b is curved in the direction of the center line Y. When puncturing the shunt blood vessel 103 from the skin 102 with the puncture needle 120, first, as shown in FIG. 21, the inclined end surface 120a of the puncture needle 120 is directed downward, and is inserted into the subcutaneous tissue 101 obliquely from the skin 102. Thereafter, the inclined end surface 120a of the puncture needle 120 is pushed toward the shunt blood vessel 103, and after the apex point 120b reaches the surface 104 of the shunt blood vessel 103, the shunt blood vessel wall is pushed downward at the apex point 120b. After the puncture point 120b is pierced into the shunt blood vessel wall, the inclined end surface 120a of the puncture needle 120 is inserted into the shunt blood vessel 103 in the same posture.

  A puncture hole 109 produced by puncturing with the inclined end surface 120a of the puncture needle 120 facing downward using a puncture needle 120 whose tip end is curved toward the center side and a flap 110 covering the puncture hole 109 are as shown in FIG. In addition, the radius of curvature is larger than that of the puncture hole 107 and the flap 108 that covers the puncture hole 107 that are normally produced using the puncture needle 100, and the shape is also projected forward with respect to the direction X, which is also the puncture direction X of the dull needle 115. It becomes an arc shape. In the flap 110 having this shape, the initial pressing portion 110b, which is the portion where the tip 115b of the dull needle 115 is pressed first, is an imaginary straight line 111a that connects both ends of the arc-shaped notch 111 in the insertion direction X of the dull needle 115. Immediately ahead. In this part, the lateral diameter of the flap 110 and the maximum lateral diameter 115e of the inclined end surface 115a of the dull needle 115 shown in FIG. Therefore, when a downward pressure greater than the shunt blood vessel pressure is applied to the flap 110 by the tip portion 115b of the dull needle 115 at this portion, the portion of the flap 110 pressed by the tip portion 115b of the dull needle 115 is The tip of the dull needle 115 is slightly shifted from the center line of the flap 110 to the left or right. Therefore, the tip of the dull needle 115 straddles the notch 111 and the opposite side of the flap 110 across the notch 111. Even when both of the shunt blood vessel walls 112 are pressed, a sufficiently long portion of the tip portion of the dull needle 115 presses the flap 110. Therefore, in the arc-shaped flap 110 that is convex forward with respect to the insertion direction X of the dull needle 115, a stress that is strong enough to separate the shunt blood vessel walls 110 and 112 on both sides of the notch 111 acts. Therefore, the flap 110 is easily opened, and the dull needle 115 is inserted into the puncture hole 109 as shown in FIG.

  However, in the flap 110 having this shape, even if the tip of the dull needle 115 once separates the shunt blood vessel walls 110 and 112 attached to both sides of the notch 111, the tip 115 b enters the puncture hole 109. In many cases, it is difficult to smoothly advance the inclined end surface 115 a of the dull needle 115 toward the back of the puncture hole 109. That is, in the flap 110 having this shape, the lateral diameter of the puncture hole 109 becomes smaller toward the front in the insertion direction X of the dull needle 115 as shown in FIG. The edge of the elliptical inclined end surface 115a of the dull needle 115 presses the edge of the puncture hole 109 from the inner side as it is pushed deeper into the back 109, so that the edge of the inclined end surface 115a of the dull needle 115 and the puncture hole are pressed. Friction with the edge of 109 increases and smooth insertion is hindered.

  As described above, when the dull needle 115 is inserted into the rearward convex flap 108, if the insertion position is shifted, the flap 108 does not rotate and the dull needle 115 is not inserted into the shunt blood vessel 103, When inserting the dull needle 115 into the forward convex flap 110, the flap 110 rotates and the dull needle 115 is inserted into the shunt blood vessel 103 even if the insertion position is slightly shifted, but it should be inserted smoothly into the back. Becomes difficult.

  The present invention has been made in view of this point, and an object of the present invention is to form a puncture hole on the shunt blood vessel wall and insert a dull needle into the shunt blood vessel from the puncture hole. When the applied flap is pressed with a strength higher than the internal pressure of the shunt vessel, the tip of the dull needle straddles the notch and the shunt vessel wall is prevented from being pressed on both sides of the notch. On the other hand, in the flap with the front end in front, the tip of the dull needle once inserted into the puncture hole presses the edge of the puncture hole from the inside, thereby preventing the tip of the dull needle from moving further into the puncture hole. It is to provide a dull needle that does not have the problem of being damaged.

  The gist of the present invention is a tubular puncture needle that is inserted into the puncture route formed from the skin surface to the surface of the shunt blood vessel and inserted into the shunt blood vessel through the puncture hole formed on the surface of the shunt blood vessel. In addition, it has an inclined end surface inclined with respect to the long axis, and further has an arcuate edge at the tip portion, and is viewed from above with the inclined end surface facing upward while standing still horizontally. Sometimes, the puncture needle is formed so that the side edges of the left and right tip portions following the arcuate tip portion are linear. In the puncture needle of such a shape, the width is smaller than the lateral width of the corresponding inclined end surface of the conventional dull needle immediately behind the arcuate edge of the tip. Therefore, in the puncture needle according to the present invention, when the optimum pressing point on the flap is pressed at the tip of the puncture needle with a strength equal to or higher than the internal pressure of the shunt blood vessel, the blood vessel wall is embedded in the shunt blood vessel wall as compared with the conventional dull needle. The length of the portion that is in close contact with the needle is short, so that the tip of the puncture needle straddles the notch and rarely presses the shunt blood vessel wall on both sides of the notch. In addition, since the puncture needle in the present invention has such a shape, the angle formed by the straight edge of the inclined end surface of the puncture needle in the present invention and the puncture direction of the puncture needle is an elliptical shape at a corresponding point of the conventional dull needle. Is smaller than the angle formed with the puncture direction of the puncture needle. Therefore, once the inclined end surface of the puncture needle inserted into the puncture hole is advanced toward the back of the puncture hole, the force with which the edge of the inclined end surface of the puncture needle presses the edge of the puncture hole from the inside is conventionally known. Therefore, the magnitude of friction between the side edge of the inclined end face of the puncture needle and the edge of the puncture hole is also smaller than that of the conventional dull needle. Therefore, in the puncture needle according to the present invention, once inserted into the puncture hole on the shunt blood vessel wall, the puncture needle proceeds further into the puncture hole more smoothly.

Further, the gist of the present invention is that the end point on the non-tip side of the linear side edge of the tip portion is a distance from the tip to the inner peripheral end on the non-tip side of the inclined end surface. / 10 to 7/10 is a puncture needle at a position where a horizontal line passing through between 10 and 7/10 intersects with the outer peripheral edge of the inclined end surface. When the end point on the non-tip side of the edge that is linear is at a position that is less than 3/10 of the distance from the tip to the inner peripheral end on the non-tip side of the inclined end surface, it is more than the arc-shaped edge of the tip The width of the puncture needle immediately behind is not sufficiently smaller than the width of the corresponding inclined end face of the conventional dull needle. Therefore, the optimum pressing point on the flap at the tip of the puncture needle is stronger than the shunt intravascular pressure. In this case, it is not possible to sufficiently prevent the tip of the puncture needle from straddling the cut and pressing the shunt blood vessel wall on both sides of the cut. Furthermore, when the end point on the non-tip side of the edge that is linear is at a position that is less than 3/10 of the distance from the tip to the inner peripheral end on the non-tip side of the inclined end surface, the straight line of the inclined end surface The angle formed by the side edge of the puncture needle with the puncture direction of the puncture needle is not sufficiently small as compared with the angle formed by the tangent line of the elliptical inclined end surface at the corresponding point of the conventional dull needle with the puncture direction of the dull needle. Once the inclined end face of the puncture needle inserted into the puncture hole is advanced toward the back of the puncture hole, the friction between the edge of the inclined end face of the puncture needle and the edge of the puncture hole cannot be reduced to the left. On the other hand, when the end point on the non-tip side of the edge that is linear is at a position that is 7/10 or more of the distance from the tip to the inner peripheral end on the non-tip side of the inclined end surface, the linear end of the inclined end surface At the point where the edge transitions to the curved edge, a vertical corner is formed between the straight edge and the curved edge, and this portion becomes caught by the edge of the puncture hole.

  The gist of the present invention is a puncture needle in which a protruding plate protrudes from the tip of the inclined end surface, and the tip of the protruding plate forms the tip of the puncture needle. In the puncture needle having such a shape, the angle formed by the long axis of the puncture needle and the linear side edge of the inclined end surface can be further reduced. Therefore, the tip of the puncture needle can be easily advanced toward the back of the puncture hole on the shunt blood vessel wall.

  Furthermore, the gist of the present invention is a puncture needle in which the lateral width of the protruding plate is 0.2 mm to 1.2 mm. If the lateral width of the projecting plate is less than 0.2 mm, the tip of the projecting plate may damage the shunt blood vessel wall. Further, in terms of processing technology, the boundary between the tip of the inclined end surface of the tubular portion and the projecting plate In addition, a relatively deep cut is formed, and when the puncture needle is inserted into the puncture hole or the puncture hole, the cut may be caught on the edge of the puncture hole. On the other hand, when the lateral width of the projecting plate is 1.2 mm or more, the width of the puncture needle immediately behind the arcuate edge of the tip is sufficiently larger than the lateral width of the corresponding inclined end face of the conventional dull needle In addition, the angle formed by the straight side edge of the inclined end surface with the puncture direction of the puncture needle is the angle formed by the tangent of the elliptical inclined end surface with the puncture direction of the dull needle at the corresponding point of the conventional dull needle. Compared with, it is not small enough.

  Furthermore, the gist of the present invention is a puncture needle in which the radius of curvature of the arc at the tip of the puncture needle is 200 μm or more and less than 4.4 mm. When the radius of curvature is less than 200 μm, the front end of the puncture needle may damage the shunt blood vessel wall. On the other hand, when the radius of curvature of the tip of the protruding plate is 4.4 mm or more, it is difficult to insert the tip of the protruding plate at the entrance of the puncture route on the skin surface.

  Furthermore, the gist of the present invention is a puncture needle in which an inclination angle of the inclined end surface with respect to the long axis of the puncture needle is less than 60 degrees. When the inclination angle of the inclined end surface is less than 60 degrees, resistance when inserting into the puncture route and the puncture hole is small.

  According to the present invention, the insertion failure of the puncture needle into the puncture hole on the shunt blood vessel wall is significantly reduced, and the progress of the puncture needle once inserted into the puncture hole on the shunt blood vessel into the back of the puncture hole is It becomes smoother.

It is a figure which shows the outline of a structure of the instrument for blood purification treatment. It is a perspective view of the tip part of a dull needle. It is a top view of the front-end | tip part of a dull needle. It is a side view of the front-end | tip part of a dull needle. It is a figure which shows the shape of a notch. It is explanatory drawing which shows a mode that the dull needle in this invention is inserted in a puncture route. It is a figure which shows the stress which acts on a notch. It is a figure which shows the notch produced on paper. P1 is a notch produced by a normal method using a normal puncture needle, and P2 is a notch produced by a puncture needle having a curved tip at an inclined end face downward. Between P1 and P2, the slit produced with the cutter knife is shown. It is a figure which shows the size of a notch. (A) is a figure of the front-end | tip of the conventional dull needle, (b) is a figure of the front-end | tip of the dull needle in this invention. (A) is a figure in which the front-end | tip of the conventional dull needle enters a puncture hole, (b) is a figure in which the front-end | tip of a dull needle in this invention enters a puncture hole. It is explanatory drawing which shows a mode that a puncture route is formed with the normal puncture needle. It is a figure which shows the shape of a notch convex back. It is a figure which shows the state just before inserting the conventional dull needle into a puncture route. It is a top view of the front-end | tip part of a normal puncture needle. It is a figure which shows a mode that the conventional dull needle is inserted in the puncture hole of a convex shape on a shunt blood vessel wall back. (A) is a top view of the front-end | tip part of a normal puncture needle, (b) is a top view of the front-end | tip part of the conventional dull needle. It is a figure which shows a mode that the front-end | tip of the conventional dull needle penetrates into the shunt blood vessel wall. It is a figure which shows the shape of a convex notch forward. It is a side view of the puncture needle in which the tip is curved. It is a figure which shows a mode that the puncture needle in which the tip is curved passes through under the skin and is inserted into the shunt blood vessel. It is a figure which shows the lateral width in the initial-pressing site | part on the flap produced with the puncture needle in which the tip is curved. It is a figure which shows a mode that the conventional dull needle is inserted in the puncture hole of a convex shape on a shunt blood vessel wall.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view showing an example of a blood purification treatment instrument 1 having a dull needle as a puncture needle in the present embodiment.

  The blood purification device 1 is for connecting, for example, a dull needle 10 punctured by a patient during blood purification processing, a tube 11 connected to the rear end portion of the dull needle 10, and a rear end portion of the tube 11 to another tube. Connection portion 12. A holding portion 13 that is held by an operator when the dull needle 10 is moved is provided in a portion near the dull needle 10 of the tube 11. A clamp 14 is attached to the tube 11. A cap 15 is fitted to the connection portion 12.

  The blood purification treatment instrument 1 is connected to another tube, for example, by a connecting portion 12 and constitutes a part of a blood purification circuit having a blood purifier (not shown). The blood purification processing instrument 1 is attached to the blood removal circuit end section and the blood return end section, and blood removal and blood return are performed through the dull needle 10 during the blood purification process. The blood purification processing includes, for example, dialysis processing, plasma exchange processing, plasma adsorption processing, blood component removal processing, and the like.

  As shown in FIGS. 2, 3, and 4, the dull needle 10 includes a tubular portion 20 having an inclined end surface 20 a that is inclined with respect to the long axis A of the dull needle, and a distal end 20 b of the inclined end surface 20 a of the tubular portion 20. A protruding plate 21 protruding like a spatula is provided on the front side. The lateral width of the protruding plate 21 (the length in the left-right direction perpendicular to the long axis A) is smaller than the lateral width of the tubular portion 20, while the thickness of the protruding plate 21 is formed to be equal to the tubular portion 20. Yes. The inner wall surface of the protruding plate 21 is continuous with the inner wall surface of the tubular portion 20, and the outer wall surface of the protruding plate 21 is continuous with the outer wall surface of the tubular portion 20.

  The front end portion 21a of the protruding plate 21 has an arc shape protruding forward. The curvature radius in the major axis direction of the arc that forms the distal end portion 21a is set smaller than the curvature radius of the distal end 20b (the dotted line portion shown in FIG. 3) of the inclined end surface 20a, for example. For example, the radius of curvature of the tip 20b of the inclined end surface 20a is 2.2 mm, whereas the radius of curvature of the arc of the tip 21a of the protruding plate 21 is set to 200 μm or more and less than 2.2 mm, for example, 0.43 mm. ing.

  As shown in FIG. 3, the side edge 21c of the projecting plate 21 following the arcuate tip 21a of the projecting plate 21 of the dull needle 10 is straight when viewed from above, and further, the inclined end surface. Of the outer peripheral edge portion of 20a, the side edge 20c of the portion following the side edge 21c of the protruding plate 21 also has a linear shape that is continuous with the side edge 21c of the protruding plate 21 when viewed from above. In other words, when the dull needle 10 is viewed from above with the dull needle 10 placed horizontally and the inclined end surface 20a facing upward, the side edges 21c and 20c of the left and right tip portions following the arcuate tip portion 21a are respectively It is formed to be linear. The end point T on the non-tip side of the straight side edges 21c and 20c of the tip portion is between 3/10 to 7/10 of the distance R1 from the tip N1 to the inner peripheral end N2 on the non-tip side of the inclined end surface 20a. The horizontal line G passing through and the outer peripheral edge of the inclined end surface 20a intersect each other.

  The inclination angle B of the inclined end face 20a with respect to the protruding direction of the protruding plate 21 (in the direction of the axis A of the puncture needle) shown in FIG. 4 is set to be less than 60 degrees. As a result, the angle formed by the inclined end surface 20a and the left and right end sides of the protruding plate 21 connected to the inclined end surface 20a is less than 60 degrees.

  The outer diameter of the tubular portion 20 of the dull needle 10 is preferably about 1.2 mm to 2.8 mm. In this case, the lateral width of the protruding plate 21 is preferably about 0.2 mm to 1.2 mm. The length of the protruding plate 21 in the axis A direction is preferably about 0.25 mm to 2.5 mm. The material of the dull needle 10 may be a metal puncture needle such as stainless steel or a plastic puncture needle. For the plastic puncture needle, polytetrafluoroethylene, ABS resin (acrylonitrile / butadiene / styrene), polycarbonate, polypropylene, polyethylene and the like are preferably used.

  Next, an operation for puncturing a shunt blood vessel using the dull needle 10 configured as described above will be described. Before the work is performed, for example, as shown in FIG. 12, the first normal puncture needle 100 is used to puncture the skin 102 from the skin 102 through the subcutaneous tissue 101 by puncturing with the tip inclined end surface facing upward. A puncture route 105 extending to the surface 104 of the blood vessel 103 is formed, and a puncture hole 107 formed by a rearwardly protruding notch 106 is formed on the surface 104 of the shunt blood vessel 103 on the extension line of the puncture route 105 as shown in FIG. Is formed. Alternatively, as shown in FIG. 21, the skin 102 penetrates through the subcutaneous tissue 101 by puncture with the tip inclined end surface facing downward using the puncture needle 120 whose tip is curved toward the lumen. A puncture route 105 is formed from the surface to the surface 104 of the shunt blood vessel 103, and the surface 104 of the shunt blood vessel 103 on the extension line of the puncture route 105 is punctured by a notch 111 protruding forward as shown in FIG. A hole 109 is formed.

  In the second and subsequent puncture operations by the dull needle 10, for example, the dull needle 10 is inserted into the puncture hole 107 formed by the notch 106 protruding backward in the insertion direction X of the dull needle 10 shown in FIG. When inserting a needle, first, the dull needle 10 is inserted into the puncture route 105 from the entrance 105a of the puncture route 105 on the skin 102 as shown in FIG. Next, when the dull needle 10 is advanced along the puncture route 105, the distal end portion 21 a of the protruding plate 21 reaches the surface 104 of the shunt blood vessel 103. Therefore, the tip 108a of the flap 108 on the surface 104 of the shunt blood vessel 103 shown in FIG. Next, the tip portion 21a of the dull needle 10 is moved to the optimum pressing portion 108b immediately in front of the tip 108a of the flap 108, and the optimum pressing portion 108b is pressed by the tip portion 21a of the protruding plate 21 with a strength higher than the shunt blood vessel internal pressure. To do. As a result, the flap 108 is pushed down into the shunt blood vessel 103 as already shown in FIG. 16, and as a result, as shown in FIG. Stress S is generated in the portion, so that the fibrin glue that has adhered the notch 106 is peeled off, the puncture hole 107 is opened, and the dull needle 10 is inserted into the shunt blood vessel 103.

  On the other hand, in the second and subsequent puncture operations by the dull needle 10, the dull needle 10 is inserted into the puncture hole 109 formed by the notch 111 protruding forward in the insertion direction X of the dull needle 10 shown in FIG. When inserting a needle, first, the dull needle 10 is inserted into the puncture route 105 from the entrance 105a of the puncture route 105 on the skin 102 as shown in FIG. Next, when the dull needle 10 is advanced along the puncture route 105, the tip 21 a of the dull needle 10 reaches the surface 104 of the shunt blood vessel 103. Therefore, as shown in FIG. 5B, the flap 110 is pressed with a strength higher than the shunt intravascular pressure while sliding the tip 21a of the dull needle 10 from the initial pressing point 110b on the flap 110 toward the tip 110a. To do. As a result, the flap 110 is pushed down into the shunt blood vessel 103 as already shown in FIG. 23, and therefore, as shown in FIG. Stress S is generated in the portion, and thus the fibrin glue that has adhered the notch 111 is peeled off, the puncture hole 109 is opened, and the dull needle 10 is inserted into the shunt blood vessel 103.

  When blood purification such as hemodialysis is performed, puncture of the shunt blood vessel with the dull needle 10 is performed at two locations on the shunt blood vessel wall, and blood is removed from the shunt blood vessel through one of the two dull needles 10. Then, after the blood that has been removed is purified in the blood purifier, the purified blood is returned to the shunt blood vessel through the other dull needle.

  According to the present embodiment, when the dull needle 10 is viewed from above in a state where the dull needle 10 is placed horizontally and the inclined end surface 20a is directed upward, the side of the left and right tip portions following the arcuate tip portion 21a. Since the edges 21c and 20c are formed so as to be linear, the width of the tip portion is smaller than the lateral width of the corresponding inclined end face of the conventional dull needle. Therefore, when the optimum pressing point on the flap 108 or the initial pressing point on the 110 is pressed with a strength higher than the shunt blood vessel internal pressure by the tip 21a of the dull needle 10, it is sunk into the shunt blood vessel wall as compared with the conventional dull needle. Thus, the length of the portion that is in close contact with the blood vessel wall is short, so that the tip 21a of the dull needle 10 straddles the cut and presses the shunt blood vessel wall on both sides of the cut. Further, the angle formed by the straight side edges 21c and 20c of the dull needle 10 with the puncture direction is smaller than the angle formed by the tangent line of the elliptical inclined end surface at the corresponding point of the conventional dull needle with the puncture direction. Therefore, when the inclined end surface 20a of the dull needle 10 once inserted into the puncture hole is advanced toward the back of the puncture hole, the force with which the side edges 21c and 20c of the dull needle 10 press the edge of the puncture hole from the inside is Therefore, the size of the friction between the side edges 21c and 20c of the dull needle 10 and the edge of the puncture hole is also smaller than that of the conventional dull needle. Therefore, once inserted into the puncture hole on the shunt blood vessel wall, the tip of the dull needle 10 advances more smoothly into the puncture hole. Therefore, in both the case where the dull needle 10 is inserted into the rearwardly convex puncture hole 107 and the case where the dull needle 10 is inserted into the forwardly convex puncture hole 109, the tip of the dull needle 10 straddles the notch. Further, in the puncture hole 109 convex forward, the tip of the dull needle 10 once inserted into the puncture hole presses the edge of the puncture hole from the inside. Thus, the problem that the tip of the dull needle 10 is prevented from proceeding further into the puncture hole is solved.

  Further, as shown in FIG. 3, the end point T on the non-tip side of the linear side edges 21c and 20c of the tip portion of the dull needle 10 is the distance from the tip N1 to the inner peripheral end N2 on the non-tip side of the inclined end surface 20a. Since the horizontal line G passing between 3/10 to 7/10 of R1 and the outer peripheral edge of the inclined end surface 20a intersect each other, the dull needle 10 can be inserted into the shunt blood vessel 103 more appropriately. In addition, the dull needle 10 can be inserted further smoothly.

  In addition, since the protruding plate 21 protrudes from the tip of the inclined end surface 20a, and the tip of the protruding plate 21 forms the tip portion 21a of the dull needle 10, the long axis A of the dull needle 10, the protruding plate 21, and the inclined end surface. The angle formed by the straight side edges 21c and 20c of 20a can be further reduced. Therefore, the tip of the dull needle 10 can be more easily advanced toward the back of the puncture hole on the shunt blood vessel wall.

  Since the lateral width of the protruding plate 21 is 0.2 mm to 1.2 mm, the tip of the protruding plate 21 can be prevented from damaging the shunt blood vessel wall. Further, in terms of processing technology, it is possible to prevent a relatively deep cut from being formed at the boundary between the tip of the inclined end surface 20a of the tubular portion 20 and the protruding plate, and to prevent the cut from being caught by the edge of the puncture hole. Further, since the width of the tip of the dull needle 10 can be made sufficiently smaller than that of the conventional dull needle, the insertion of the tip of the dull needle 10 into the shunt blood vessel 103 and the insertion of the tip of the dull needle 10 further into the back are further performed. It can be done smoothly.

  Since the radius of curvature of the arc of the tip 21a of the dull needle 10 is 200 μm or more and less than 4.4 mm, the front end of the dull needle 10 can be prevented from damaging the shunt blood vessel wall. Moreover, it becomes easy to insert the tip of the protruding plate 20 into the entrance of the puncture route on the skin surface.

  Since the inclination angle B of the inclined end surface 20a with respect to the long axis A of the dull needle 10 is less than 60 degrees, the resistance when inserting into the puncture route and the puncture hole can be reduced.

The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the idea described in the claims, and these naturally belong to the technical scope of the present invention. It is understood.

  For example, the shape of the protruding plate 21 of the dull needle 10 is not limited to that described in the above embodiment, but may have other shapes. For example, the protruding plate 21 may have a shape such that only the width of the tip portion 21a is smaller than the other portions. Moreover, in the said embodiment, although the curvature radius in the dull needle long axis direction of the front-end | tip part 21a of the protrusion board 21 was smaller than the curvature radius in the dull needle long-axis direction of the front-end | tip 20b of the inclination end surface 20a, this is 200 micrometers-4 The relationship may be reversed as long as it is 4 mm. Furthermore, the protruding plate 21 is not always necessary, and the side edge that continues from the tip 20b of the inclined end surface 20a of the dull needle 10 to the rear may be formed linearly. Moreover, in the said embodiment, although the dull needle 10 was an AVF specification used at the time of a blood purification process, an indwelling needle specification may be sufficient. Furthermore, what is necessary is just to be used by the buttonhole puncture method. For example, the present invention can be applied to a dull needle that is used when a drug solution is administered by a syringe or when blood is collected.

(Evaluation Experiment 1)
In order to clarify the shape and size of the notch formed on the surface of the shunt blood vessel, a blank paper was punctured with a normal puncture needle having a sharp tip of 16G at an angle of 30 ° with the inclined end surface facing upward. Thus, a notch protruding backward (corresponding to the notch 106) with respect to the puncture direction was produced. On the other hand, a 16G puncture needle having a sharp point on the side and curved toward the lumen of the puncture needle, the inclined end surface of the puncture needle is directed downward with respect to the surface. A blank paper was punctured at an angle of 30 ° to produce a notch convex forward (corresponding to the notch 111) with respect to the puncture direction. A slit having a width of 4 mm was prepared between the two notches 106 and 111 by a cutter knife as a control. Thereafter, the flaps were turned upside down at the two notches 106 and 111, and black paper was overlaid to enlarge and copy the paper on which the notches were made. Based on this, the specific shapes and sizes of the notches 106 and 111 were clarified. FIG. 8 shows an enlarged copy P1 of a notch produced by a normal method using a normal puncture needle, and a puncture needle whose tip is curved toward the lumen of the puncture needle, with the inclined end surface facing downward. The created enlarged copy P2 of the notch is shown together with the enlarged copy of the slit.

  FIG. 9A shows the size of the notch 106 that protrudes backward with respect to the puncture direction, and is shown in FIG. 9B with respect to the puncture direction. The size of the notch 111 convex forward is shown. Usually, the notch 106 with a puncture needle has a radius of curvature of 0.79 mm, a string length of 1.30 mm, a distance from the base point 106b to the string of 0.36 mm, and a puncture whose tip is curved in the direction of the central axis The radius of curvature of the notch 111 by the needle was 1.20 mm, the length of the string was 1.25 mm, and the distance from the bottom 111b to the string was 0.21 mm.

(Evaluation Experiment 2)
At the time of buttonhole puncture, the flap is pressed with the tip of the dull needle to generate stress in the adhered incision, pulling away the shunt blood vessel walls on both sides of the incision, and opening the puncture hole. At that time, in order to reduce the ratio of the tip part of the dull needle that presses against the shunt blood vessel wall that is not the flap part across the notch, the dull needle that is indented into the shunt blood vessel wall and touches the shunt blood vessel wall. It is better that the length of the tip of the is shorter. By the way, as shown in FIG.2, FIG.3, FIG.4, the protrusion board 21 protrudes from the inclination end surface 20a of the dull needle 10 in this invention. 10B, the lateral width 21d of the protruding plate 21 at a constant distance from the tip 21a of the dull needle 10 is an inclined end surface at the same distance from the tip 115b of the conventional dull needle 115 shown in FIG. 10A. The width of 115a is smaller than 115d. Therefore, the tip of the conventional dull needle 115 or the tip of the dull needle 10 according to the present invention holds the optimum pressing point 108b on the flap 108 on the shunt blood vessel 103 shown in FIG. Alternatively, when the initial pressing point 110b on the flap 110 on the shunt blood vessel 103 shown in FIG. 7 (b) is pressed with a strength equal to or higher than the shunt blood vessel internal pressure, the dull needle 10 of the present invention is more than the conventional dull needle 115. The length of the distal end portion that is indented into the shunt blood vessel wall and contacts the shunt blood vessel wall is shortened. Therefore, in the dull needle 10 according to the present invention, the phenomenon that the tip of the dull needle 10 straddles the notch 106 or the notch 111 and presses the shunt blood vessel wall on both sides of the notch 106 or the notch 111 hardly occurs.

  Evaluation experiment 2 is an experiment for confirming the above description. That is, in the evaluation experiment 2, when the shunt blood vessel wall is pressed with a strength higher than the shunt blood vessel pressure by the tip of the conventional dull needle 115 or the tip of the dull needle 10 in the present invention, This is an experiment for confirming that the length of the tip portion in contact with the shunt blood vessel wall is actually shorter than the dull needle 115.

  In the portion where the shunt blood vessel is extremely angry, the skin is not thinned, and there is almost no subcutaneous tissue between the shunt blood vessel wall and the skin. Therefore, when the skin is pressed by the tip of the dull needle at this site, the tip of the dull needle sinks into the skin as much as the tip of the dull needle sinks into the shunt vessel wall when the shunt vessel wall is pressed directly. That is, by pressing this portion with the tip of the dull needle and evaluating the length of the tip of the dull needle that touches the skin, if the shunt blood vessel wall is directly pressed by the tip of the dull needle, the shunt touched by the tip of the dull needle The length of the vessel wall can be estimated.

  For this experiment, the outer diameter of the cross section is 1.6 mm, the lateral width of the protruding plate 21 is 0.8 mm, and the outer diameter of the cross section is 1.6 mm as well, A conventional dull needle with an inclined end face having an elliptical shape and no protruding plate 21 was prepared. Ink was applied to the tip of each dull needle. In 10 dialysis patients with shunt blood vessels in the forearm and shunt blood vessels angling and meandering, the length of 1 mm as a ruler is first placed on the skin surface directly above the shunt blood vessels that are angry and meandering. A thin tape was affixed. Next, the upper arm on the side where the shunt blood vessel is present is driven with a tourniquet, and then the dull needle is inserted into the puncture hole with the tip of each of the dull needle 10 according to the present invention and the conventional dull needle 115 in the sense of the operator. The surface of the skin was pressed at a site near the tape that was applied as a ruler at a force approximately equal to the force sometimes applied and at an angle of 30 °. After that, each ink ink produced by observing the skin immediately above the shunt blood vessel that is meandering with magnifying glass using a magnifying glass and pressing with the length of the tape as a ruler and the tip of the dull needle. By comparing the length of each ink stain, the length of each ink stain was visually evaluated.

  As a result of the evaluation experiment 2, the conventional dull needle has a stain length of 1.2 mm, whereas the dull needle according to the present invention has a stain length of 0.8 mm. The tip length touching the skin was shorter than in.

  By the way, as shown in FIGS. 9A and 5A, in the puncture hole 107 formed by the notch 106 convex rearward with respect to the puncture direction X, the length of the string 106c passing through the optimum pressing portion 108b is as follows. On the other hand, as shown in FIGS. 9B and 5B, in the puncture hole 109 formed by the notch 111 convex forward with respect to the puncture direction, the string passing through the initial pressing portion 110b. The length of 111c was 0.96 mm, and the horizontal diameter of the pressed part was almost equal to the horizontal width of the protruding plate 21 of the dull needle 10 in any puncture hole. Therefore, even if it is the conventional dull needle or the dull needle of the present invention, if the flap portion pressed by the dull needle is slightly shifted from the center of the flap to the left or right, the tip of the dull needle is Not only does it compress the shunt vessel wall on the opposite side of the flap across the notch. At this time, if the length of the tip that presses the flap is longer than the length of the tip that presses the shunt vessel wall on the opposite side of the flap across the notch, the fibrin that adheres the shunt vessel walls on both sides Easy to peel off glue. Now, in the dull needle of the present invention, the length of the tip portion in contact with the shunt blood vessel wall is shorter than that of a normal dull needle. Therefore, in the dull needle in the present invention, it seems that the range on the flap 108 to which the tip of the dull needle should be pressed in order to open the puncture hole by pushing down the flap is larger than in the conventional dull needle.

  For example, if the flap 108 is pushed down to open the puncture hole 107, if at least 2/3 of the length of the tip of the dull needle contacting the shunt blood vessel wall must be on the flap 108, In the dull needle 115, the flap 108 must be pressed by 0.8 mm out of 1.2 mm which is the length of the ink stain, that is, the length of the tip portion in contact with the shunt blood vessel wall. In order to do so, the tip of the dull needle must press the shunt blood vessel wall surface on the flap side by 0.2 mm from the notch 106. That is, if the remaining range on the flap 108 is removed from the left leg and the right leg of the notch 106, each within a range of 0.2 mm or less, the shunt blood vessel walls on both sides of the notch 106 are adhered. It will be possible to peel off the fibrin glue. Therefore, the range on the flap 108 to be pressed to peel off the fibrin glue is 0.36 mm obtained by subtracting 0.2 mm from 0.76 mm which is the lateral width of the flap 108 at the optimum pressing portion 108b. On the other hand, in the case of the dull needle 10 according to the present invention, in order to peel off the fibrin glue that adheres the shunt vessel walls on both sides of the notch 106, the length of the tip portion in contact with the shunt vessel wall is at least 2 / If three or more must be on the flap 108, the flap 108 is pressed at 0.53 mm out of the length of the ink stain, that is, 0.8 mm which is the length of the tip in contact with the shunt blood vessel wall. Must be. At this time, if the tip of the dull needle presses the remaining area on the flap 108 except for the area within 0.13 mm from the notch 106, the shunt blood vessel walls on both sides of the notch 106 are adhered. It will be possible to peel off the fibrin glue. Therefore, the range on the flap 108 to be pressed to peel off the fibrin glue is 0.5 mm obtained by subtracting 0.13 mm from 0.76 mm which is the lateral width of the flap 108 at the optimum pressing portion 108b.

  Actually, in order to peel off the fibrin glue adhering the shunt vessel walls on both sides of the notch 106 and open the puncture hole 107 by pushing down the flap 108, the length of the tip portion in contact with the shunt vessel wall is long. It is unclear exactly how much of this should be on the flap 108. However, in order to tear off the fibrin glue that adheres the shunt vessel walls on both sides of the notch 106, what is the ratio of the tip length that must be on the flap 108 to occupy the entire tip length? It is clear that the area on the flap 108 to be pressed to tear off the fibrin glue is wider with the dull needle in the present invention than in the conventional dull needle.

(Evaluation Experiment 3)
If the tip of the dull needle is slightly shifted to the left or right of the center line in the puncture hole, the tip of the dull needle is pushed toward the back of the shunt blood vessel, The side edge hits the edge of the puncture hole and presses the edge of the puncture hole outward, so that friction occurs between the side edge of the inclined end surface of the dull needle and the edge of the puncture hole. In particular, in the puncture hole 109 that is curved forward in the insertion direction of the dull needle, the lateral diameter of the puncture hole becomes smaller toward the front in the insertion direction of the dull needle, so this phenomenon is likely to appear. .

  In the dull needle 10 according to the present invention, as shown in FIGS. 3 and 10 (b), among the outer peripheral edge portions of the inclined end surface 20a of the dull needle 10, the portions that continue from the tip 21a to the left and right are respectively viewed from the top surface. The side edges 21c and 20c are linear. Therefore, in the dull needle 10 according to the present invention, the above phenomenon is less likely to appear as compared with the conventional dull needle 115 shown in FIG.

  As shown in FIG. 10A, in the conventional dull needle 115, the edge 115c of the tip is a part of the peripheral edge of the elliptical inclined end surface 115a. 11A, the force FC1 for pushing the tip of the dull needle 115 toward the back of the puncture hole 109 is such that the side edge of the inclined end surface 115a of the dull needle 115 contacts the edge of the puncture hole 109. In Q1, the force component in the direction perpendicular to the tangent L1 at the elliptical point corresponding to the shape of the inclined end surface, that is, the force component FC2 pushing the edge of the puncture hole, and the puncture hole 109 along the tangent L1 The force component in the central direction, that is, the force component FC3 for returning the dull needle 115 to the direction of the center line C of the puncture hole 109 is divided. On the other hand, in the dull needle 10 according to the present invention, as shown in FIG. 10 (b), the side edges 21c and 20c of the distal end that press the edge of the puncture hole 109 are linear edges that follow the arcuate distal end 21a. is there. Then, as shown in FIG. 11B, the force FN1 for pushing the tip of the dull needle 10 toward the back of the puncture hole 109 is a point Q2 where the tip of the dull needle 10 contacts the edge of the puncture hole 109. The component of the force in the direction perpendicular to the straight side edges 21c and 20c of the tip portion of the tip 10, that is, the component FN2 of the force pushing the edge of the puncture hole, and the center line C of the puncture hole 109 along the side edge Force component FN3, that is, a force component FN3 for returning the dull needle to the direction of the center line of the puncture hole.

  Now, as shown in FIG. 11 (b), the angle E2 formed by the straight side edges 21c and 20c of the tip of the dull needle 10 according to the present invention with respect to the traveling direction C of the dull needle is the inclined end surface of the conventional dull needle 115. A tangent L1 at a point Q1 where the side edge of 115a contacts the edge of the puncture hole 107 is smaller than an angle E1 formed with respect to the traveling direction C of the dull needle 10. Therefore, when the dull needle 10 according to the present invention and the conventional dull needle 115 are pushed toward the back of the puncture hole 109 with the same strength, the edge of the puncture hole 107 is greater in the dull needle 10 in the present invention than in the conventional dull needle 115. On the other hand, the force to push the dull needle back toward the center line C of the puncture hole 107 is large.

  In order to confirm whether or not the dull needle in the present invention enters the back of the puncture hole more smoothly than the conventional dull needle, evaluation experiment 3 was conducted. Evaluation experiment 3 was conducted on 40 patients with end-stage renal failure hemodialysis who had a self-intravascular shunt on the forearm and a convex flap forward in the puncture direction of the puncture route and dull needle between the skin and the shunt vessel. Each of the three dialysis center nurses performed 120 buttonhole punctures for each patient using the dull needle 10 according to the present invention shown in FIG. 2, FIG. 3 and FIG. Further, after that, the same three nurses performed 120 buttonhole punctures using the conventional dull needle 115 shown in FIG. 17B. If one of the three nurses reported that he felt resistance when advancing the tip of the dull needle into the puncture hole, the buttonhole puncture using that dull needle for the patient was If all three nurses reported no resistance when advancing the tip of the dull needle into the puncture hole, a buttonhole puncture using the dull needle for the patient was made. Considered "no resistance". The results of this evaluation experiment 3 are shown in Table 1 below.

本発明に係るダルニードル１０を使用した場合には、従来のダルニードル１１５を使用した場合よりも「抵抗なし」の比率が高かった。

When the dull needle 10 according to the present invention was used, the ratio of “no resistance” was higher than when the conventional dull needle 115 was used.

(Evaluation Experiment 4)
Evaluation Experiment 4 uses a load measuring device (MODEL-1605N: manufactured by Aiko Engineering Co., Ltd.) and punctures each sample after puncturing with a 17G puncture needle against silicon rubber (SR-50; manufactured by Tiger Polymer Co., Ltd.) having a thickness of 1.05 mm and 40 mmΦ. The dull needle was pierced and the required load at that time was measured. As experimental conditions, the piercing speed was 50 mm / min at a room temperature of 26 ° C. The results of this evaluation experiment 4 are shown in Table 2. The maximum required load in Table 2 is the maximum load required when each sample is pierced, and the contact required load is the contact between the protruding plate 21 of the dull needle and the inclined end surface 20a piercing the silicon rubber. This is the load that was needed.

  In the samples of Examples 1, 2, 3 and Comparative Example 1, the contact angle (inclination angle) B between the protruding plate 21 and the inclined end surface 20a is 11.5 degrees, 25.3 degrees, 35.1 degrees, 65. It is a 3 degree dull needle. The sample of Comparative Example 2 is a dull needle that does not have the protruding plate 21 shown in FIG.

  The maximum required loads of Examples 1 to 3 having a contact angle B of less than 60 degrees are significantly smaller than those of Comparative Examples 1 and 2. Moreover, the contact required load of Examples 1-3 is 100 mN or less, and is remarkably small with respect to Comparative Example 1. Therefore, by making the contact angle B less than 60 degrees, the piercing resistance is remarkably lowered, and puncture can be performed smoothly.

DESCRIPTION OF SYMBOLS 1 Blood purification processing instrument 10 Dull needle 11 Tube 12 Connection part 13 Holding part 14 Clamp 15 Cap 20 Tubular part 20a Inclined end face 20c Side edge 21 Projection plate 21a Tip part 21c Side edge 21d Width of projection board 100 Normal puncture needle 100b Point 100c Blade line 101 Subcutaneous tissue 102 Skin 103 Shunt blood vessel 104 Shunt blood vessel surface 105 Puncture route 105a Puncture route entrance 106, 111 Notch 106a Virtual straight line 106b Bottom point 107, 109 Puncture hole 108, 110 Flap 108a Tip 108b Optimal pressing part 110b Initial pressing point 111a Virtual straight line 112 Blood vessel wall 115 Conventional dull needle 115e Maximum lateral diameter of inclined end face 120 Puncture needle 120b Apical point A, C, X, Y axis or direction B, E1, E2 Angle FC1, FC2, FC3, FN1 , FN2, FN3 force components

Claims (6)

A tubular puncture needle that is inserted into a puncture route formed from the skin surface to the surface of the shunt blood vessel and inserted into the shunt blood vessel through a puncture hole formed on the surface of the shunt blood vessel,
Having an inclined end surface inclined with respect to the major axis;
Furthermore, the tip is an arcuate edge,
And it is formed so that the side edges of the left and right tip portions following the arc-shaped tip portion are each linear when viewed from above with the inclined end face facing upward. Puncture needle.   The end point on the non-tip side of the straight side edge of the tip portion is a horizontal line passing between 3/10 to 7/10 of the distance from the tip to the inner peripheral end on the non-tip side of the inclined end surface starting from the tip. The puncture needle according to claim 1, which is at a position where the outer peripheral edge of the inclined end surface intersects each other. The puncture needle according to claim 1 or 2, wherein a protruding plate protrudes from a tip of the inclined end surface, and a tip of the protruding plate forms a tip of the puncture needle.   The puncture needle according to claim 3, wherein the protruding plate has a lateral width of 0.2 mm to 1.2 mm.   The puncture needle according to any one of claims 1 to 4, wherein a radius of curvature of a circular arc at a tip portion of the puncture needle is 200 µm to 4.4 mm.   The puncture needle according to any one of claims 1 to 5, wherein an inclination angle of the inclined end surface with respect to the long axis of the puncture needle is less than 60 degrees.

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