JPH1094601A - Intravenous cannula - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intraveous cannula which is inexpensively produced, prevents the repetition, failure, etc., of puncture work so as to ensure the execution of safe work, enables the sure check of the indwelling of an inside needle and pallial needle and has high reliability. SOLUTION: This intraveous cannula has a needle part 3 which has an internal cavity 3a penetrating the needle part in its longitudinal direction and a needle tip 3b diagonally cut at its one end and consists of a metallic material provided with a side hole 4 at the side wall near this needle tip 3b, the inside needle 2 which is connected to the other end of the needle part 3 and is composed of an inside needle hub consisting of plastic and the pallial needle 8 which has an internal cavity 9a of the bore nearly equal to the outside diameter of the needle part 3, comprises a pallial part 9 covering the needle part 3 exclusive of the needle top 3b side and a pallial needle hub disposed at the other end of the pallial part 9 and consists of plastic. The side hole 4 is inserted into the needle tip side internal cavity 3a of the needle part 3 communicably with the internal cavity 3a. The intraveous cannula has a closing member 11 which closes the aperture at the same plane as the edge plane of the needle tip 3b and consists of a metallic material or synthetic resin material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indwelling needle, and more particularly, to an indwelling catheter such as a venous indwelling needle, a central venous catheter, etc., which is provided with an inner needle and an outer needle and is used for administration or dialysis of a drug solution or infusion. The present invention relates to an indwelling needle used for inserting a guide wire.

[0002]

2. Description of the Related Art FIG. 7 is an explanatory view of a configuration of a conventional indwelling needle and an enlarged sectional view of a main part thereof. In the figure, reference numeral 21 denotes an indwelling needle constituted by a metal inner needle 22 and a plastic outer needle 25 slidably mounted on the inner needle 22. The inner needle 22 has a lumen 23a penetrating in the longitudinal direction, and is provided with a needle portion 23b made of a metal material such as stainless steel and having a needle tip portion 23b having one end cut obliquely and formed into a needle tip shape. And an inner needle hub 24 made of plastic connected to the other end of the needle portion 23 and connected to a luer tip of a syringe (not shown) or the like. Has an inner lumen 26a having an inner diameter substantially equal to the outer diameter of the outer needle 26, one end of which is reduced in diameter toward the distal end, and the inner needle 22 connected to the other end of the outer cover 26.
And an outer trocar hub 27 to which the inner needle hub 24 is connected.

When using the indwelling needle 21 configured as described above, first, the needle tip 23b of the inner needle 22 is inserted into the inner cavity 26a of the outer sleeve 26 from the outer needle hub 27 side of the outer needle 25. Then, the outer trocar hub 27 and the distal end side of the inner needle hub 24 are connected to each other, and the needle tip 23b is inserted until it penetrates the outer wrap 26, and as shown in FIG.
Attach to 2. Next, after connecting the syringe to the inner needle hub 24 of the inner needle 22, the patient's body tissue is punctured with the sharp needle tip 23b of the inner needle 22, and the inner needle 22 is inserted into the blood vessel together with the outer trocar 25. At this time, it is confirmed that the inner needle 22 has entered the blood vessel by the blood (generally referred to as flashback) flowing into the lumen 23a from the opening of the needle tip 23b of the inner needle 22. Next, as shown in FIG.
1 is further advanced by 3 to 4 mm, and the mantle portion 2 of the mantle 25 is moved.
After predicting that the distal end portion 26b of the No. 6 has entered the blood vessel K, only the trocar 25 is further pushed forward by several millimeters, the inner needle 22 is removed together with the syringe, and the trocar 25 is placed in the blood vessel K. Then, dialysis or the like is performed using the outer trocar 25.

[0004]

The conventional indwelling needle 21 as described above often fails in puncturing the blood vessel K, and its success or failure largely depends on the sense and intuition of the doctor. ing. That is, despite flashback being confirmed in the above puncturing operation, FIG.
As shown in (a) or (b), the tip 26b of the remaining trocar 25 is often not placed in the target blood vessel K.

As shown in FIG. 7 (b), this is the tip 2 of the inner wall on the side of the tip 23e of the needle tip 23b of the inner needle 22 projecting from the tip 26b of the outer sleeve 26 of the outer needle 25.
The distance m1 between 3d and the tip 26b of the mantle part 26 is about 3 to
This is because the distance is 4 mm. In other words, the moment the flashback is confirmed, the opening (lumen 23 a) of the needle tip 23 b of the inner needle 22 is located inside the blood vessel K. Since it is not possible to confirm that 26b is located in the blood vessel K, in order to bring the distal end 26b of the trocar 25 into the blood vessel K, the distal end 23d of the needle tip 23b of the inner needle 22 is moved. It is necessary to push the trocar 25 by the distance m1 from the tip portion 26b of the trocar 25, and the degree of the pushing depends solely on the prediction based on the experience of the individual doctor. In order to securely insert the portion 26b into the blood vessel K, a deeper puncture than necessary is performed, thereby damaging the blood vessel K wall. FIG. 8 (d)
As shown in Fig. 7, there is a possibility that the blood vessel K may be pierced to damage important human tissues or organs, resulting in a serious crisis.

Therefore, in order to solve such a problem, it is conceivable to make it possible to confirm by flashback even when the trocar 25 of the indwelling needle 21 is punctured into the blood vessel K. However, for example,
No. 2,2751, Japanese Patent Publication No. 6-93917, Japanese Utility Model Application Laid-Open No. 62-72649, and Japanese Patent Application Laid-Open No. 63-2521.
No. 67 discloses this. These are provided with a groove in the longitudinal direction of the outer peripheral surface of the needle portion of the inner needle, visually confirming that blood flows back through the groove when performing a puncture operation from a transparent or translucent trocar, This confirms that both the inner needle and the outer trocar are located in the blood vessel.

However, looking back at the method of manufacturing a metal inner needle used for a general indwelling needle, a stainless steel plate is processed continuously and in large quantities into a cylindrical shape, simultaneously welded into a pipe shape, and then swaged. Manufactured in a manner to obtain a needle tube having the desired outer and inner diameters, which allows for a cheap supply. Therefore,
In order to obtain an inner needle having a special cross-sectional shape such as providing a groove as seen in the indwelling needle disclosed in Japanese Patent Application Laid-Open No. 8-22751, a special processing method is required separately, and a conventional shape (cylindrical shape) is required. ) Has become significantly more expensive than the inner needle, and is not realistic or practically used as a disposable general-purpose medical device in medical practice.

[0008] Further, the indwelling needle is required to have low resistance to human tissue at the time of puncturing, that is, to have a good cutting performance. The sharpness of the indwelling needle is determined by factors such as the shape of the tip of the inner needle, the shape of the tip of the trocar, and the lubricant coated on the indwelling needle. The thicker the wall, the better the cut, and the needle-like shape is the best. However, there is a problem in that flashback cannot be confirmed if it is formed in a needle shape.

Furthermore, since the conventional indwelling needle 21 uses the hollow metal inner needle 22 having the lumen 23a penetrating in the longitudinal direction, as shown in FIG. There is also a problem that the blood vessel K is damaged by cutting. Even in this problem, it can be said that it is ideal to make the shape of the distal end of the inner needle 22 into a round needle shape.
After all, flashback cannot be confirmed.
It was not possible to confirm that 1 was located in the blood vessel K.

The present invention has been made in order to solve the above-mentioned problems, and can be manufactured at a low cost, and can perform the work safely by preventing repetition or failure of the puncture work. It is an object of the present invention to provide a highly reliable indwelling needle that can reliably confirm the placement of an inner needle and an outer trocar.

[0011]

An indwelling needle according to the present invention comprises:
A needle portion made of a metal material having a bore penetrating in the longitudinal direction, having a needle tip cut at an angle at one end, and having a side hole formed in a side wall near the needle tip, and a needle portion; An inner needle constituted by an inner needle hub made of plastic connected to the end, and a lumen having an inner diameter substantially equal to the outer diameter of the needle portion of the inner needle,
An outer jacket made of plastic constituted by an outer jacket covering the needle section except for the needle tip side of the needle section, and an outer jacket hub provided at the other end of the outer jacket, and a needle tip of the needle section of the inner needle A side hole is inserted into the side lumen so as to be able to communicate with the lumen, and a closing member made of a metal material or a synthetic resin material is provided to close the opening in the same plane as the cutting surface of the needle tip.

Further, in the indwelling needle according to the present invention, the distance between the center of the side hole and the perpendicular drawn down from the jaw portion on the side wall of the needle portion facing the jaw portion is 3 mm. And the closing member is desirably within 1 mm, and the closing member is formed such that the base side of the needle tip which is opposed to the blade tip surface of the tip end side substantially coincides with the tip end side of the side hole or slightly has the base of the side hole. It is located on the side and is inclined obliquely upward toward the jaw portion side of the needle tip, and is cut away so as to form a blood flow path between the side hole.

Further, in the indwelling needle according to the present invention, the distance between the jaw and the tip of the side hole on the side wall of the jaw of the needle tip is 2 mm or less. In addition, the closing member is formed such that the base side of the closing member substantially coincides with or is slightly located on the base side of the side hole.

In the indwelling needle according to the present invention, when the outer sleeve of the outer needle is attached to the inner needle, the distal end of the outer sleeve does not protrude from the jaw of the needle tip and is substantially flush with the base side of the side hole. It is formed to have a length that matches or covers a part of the base side of the side hole.

In the indwelling needle according to the present invention, the length of the outer jacket covering the side hole is such that the distance between the tip of the outer jacket and the base side of the side hole is 2 mm or less. It is.

As described above, in the indwelling needle having the trocar attached to the inner needle in which the inner lumen of the distal end portion of the needle portion provided with the side hole near the needle tip is closed by the closing member, the distal end portion of the inner needle Since the shape is a needle-like shape, resistance to human body tissue is low, and puncturing can be performed easily and safely. In addition, when flashback is confirmed by blood flowing out of the side hole into the lumen of the inner needle, not only the inner needle but also the outer trocar is securely located in the blood vessel, and the indwelling operation is extremely easy. is there.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a top view, a cross-sectional view, and a bottom view of a main part of the first embodiment of the present invention, and FIG. 2 is a cross-sectional view and a XX cross-sectional view of a main part of the inner needle according to the first embodiment. FIG. 3 is an explanatory view of the configuration of the first embodiment of the present invention. In the figure,
Reference numeral 1 denotes a metal inner needle 2 having an Muku needle-like tip, and an inner needle 2
This is an indwelling needle constituted by a plastic trocar 8 slidably mounted on the inner needle 2 and a closing member 11 for closing the distal end of the inner needle 2.

The inner needle 2 has a bore 3a penetrating in the longitudinal direction, has a needle tip 3b formed by cutting one end obliquely and having a needle blade tip shape, and is provided with a jaw 3c of the needle tip 3b. A needle portion 3 made of a metal material such as stainless steel and provided with a substantially elliptical side hole 4 on the opposing side wall, and a plastic connected to the other end of the needle portion 3 and connected to the luer tip 13a of the syringe 13 and the like. And a side hole 4 provided in the side wall of the needle portion 3 of the inner needle 2,
As shown in FIG. 1 (c), the major axis is located in the longitudinal direction of the inner needle 2, and as shown in FIG. 2 (a), the jaw 3 of the needle tip 3b
intersection 6 with the side wall of the perpendicular S lowered from c to the side hole 4 side;
The side hole 4 is formed so that the distance m2 from the center 7 of the major axis is within 3 mm, preferably within 1 mm. In addition, the size of the opening area of the side hole 4 differs depending on the application, and it is desirable that the opening area be large in view of the speed of the blood flowing backward to the lumen 3a of the inner needle 2. However, if it is too large, it is not possible to fulfill one of the objects of the present invention that the operation can be performed safely while preventing repetition or failure of the puncturing operation. Therefore, for example, the outer diameter r1 of the needle portion 3 of the inner needle 2 (FIG. 2) In the case of (a)) having a size of 1.65 mm, an elliptical shape having a major axis of 1 to 3 mm and a minor axis of 0.5 to 1 mm is desirable. In addition, the processing method of the side hole 4 may be any processing method such as press punching processing, electric discharge processing, grinding processing, electrolytic grinding processing, laser processing, and processing with a drill.

The outer trocar 8 has a lumen 9a having an inner diameter substantially equal to the outer diameter of the needle portion 3 of the inner needle 2. One end of the outer trocar 9 is reduced in diameter toward the distal end. Inner needle 2 connected to the end
And an outer trocar hub 10 to which the inner needle hub 5 is connected. As shown in FIG. The portion 9b is formed so as not to protrude from the jaw portion 3c of the needle tip portion 3b and to have a length substantially matching the base 4b side of the side hole 4 or covering a part of the base 4b of the side hole 4. In addition, the outer cover 9 is provided with the side hole 4.
As shown in FIG. 1 (c), the distance m3 between the tip 9b of the mantle 9 and the base 4b of the side hole 4 is preferably 2 mm or less.

The closing member 11 is made of, for example, a metal material such as stainless steel, brass or aluminum, in particular, stainless steel of the same material as the inner needle 2, especially SUS304. As shown in FIG. The tip 11a is inserted on the tip side (needle tip 3b side), and the tip 11a side closes the opening in the same plane as the blade tip surface 3d of the needle tip 3b.
The base 11b side facing the blade tip surface 3d on the side of the tip 3e of b is substantially coincident with the tip 4a side of the side hole 4 or slightly located on the base 4b side of the side hole 4 and the jaw portion of the needle tip 3b. It is inclined obliquely upward toward the 3c side, and is cut off so as to form a blood flow path 12 between itself and the side hole 4. The needle tip 3b of the needle 3 is formed in a needle shape by the closing member 11. The material forming the closing member 11 may be a polymer material such as an epoxy resin, an ionomer resin, or a polycarbonate resin, for example, as long as the material only closes the opening of the needle tip 3b. In consideration of this, a metallic material is desirable for forming the needle tip 3b in a rounded needle shape. When the closing member 11 is packed into the needle tip portion 3b of the inner needle 2, there are a metal material, a press-fitting method, a welding method, a method using both of them, and the like. There is a processing method such as a heat welding method or an adhesion method, and any processing method may be used.

The indwelling needle 1 according to this embodiment is
A side hole 4 is formed in a stainless pipe constituting the needle portion 3 of the inner needle 2 by press punching, and the base 11b is formed as described above.
After press-fitting the cylindrical closing member 11 whose part of the side is cut off from the distal end of the stainless steel pipe into the lumen of the pipe, spot welding is performed and cut so that the needle part 3 is formed. 3b is processed into a needle shape by a processing machine. At this time, the position of the side hole 4 is adjusted to be an appropriate position. Then, the inner needle hub 5 is welded to the base side of the needle portion 3, and the indwelling needle 1 is constituted by the formed inner needle 2 and outer trocar 8.

In this embodiment constructed as above, first, the needle tip 3b of the inner needle 2 is inserted into the lumen 9a of the outer sleeve 9 from the outer needle hub 10 side of the outer needle 8, and the outer needle hub The outer needle 5 is mounted on the inner needle 2 by inserting the needle 10 into the distal end side of the inner needle hub 5 and inserting the needle tip 3b through the outer sleeve 9. Then, as shown in FIG. 3, the syringe 13 is connected to the inner needle hub 5 of the inner needle 2 of the indwelling needle 1 which has been mounted, and the patient's body tissue is punctured with the sharp needle tip 3b of the inner needle 2. Next, as shown in FIG. 4, the inner needle 2 is inserted into the blood vessel K together with the outer trocar 8, and as shown by the arrow Y, the blood flows out of the side hole 4 through the flow path 12 and into the lumen 3a. Check flashback. If flashback is confirmed,
The inner needle 2 has entered the blood vessel K. If the side hole 4 is not completely located in the blood vessel K, blood does not flow out into the lumen 3a.
The distal end portion 9b of the mantle portion 9 of the mantle 8 formed to have a length substantially coincident with the base portion 4b side of the side hole 4 or covering a part of the base portion 4b side of the side hole 4 surely enters the blood vessel K. It will be. After confirming the flashback, the inner needle 2 is removed together with the syringe 13, the trocar 8 is placed in the blood vessel K, and dialysis or the like is performed using the trocar 8.

As described above, a part of the side hole 4 provided in the side wall of the inner needle 2 facing the jaw portion 3c of the needle tip 3b is covered with the distal end portion 9b of the outer sleeve 9 of the outer needle 8, The needle tip 3 of the inner needle 2 is closed by the closing member 11 forming a flow path 12 between the needle 3 and the inner needle 2.
Since the indwelling needle 1 is formed so as to close the opening of the lumen 3a of b, when the indwelling needle 1 is punctured into the blood vessel K and flashback is confirmed, not only the inner needle 2 but also the outer trocar 8
Is located in the blood vessel K, and it is not necessary to push the trocar a few millimeters further, depending on the experience and intuition of the doctor, as in the case of using a conventional indwelling needle. Thereby, it becomes easy to indwell the indwelling needle 1, especially the trocar 8, at an appropriate position in the blood vessel K, and it is unnecessary to repeat the puncturing operation or to insert the distal end 9 b of the trocar 8 into the blood vessel K. There is no danger that a deep puncture will damage the blood vessel wall or important organs and cause a serious crisis.

The needle tip 3b of the inner needle 2 is
Therefore, the resistance to human tissue at the time of puncturing is low, and a sharp indwelling needle can be obtained. As a result, unnecessary force is not required at the time of puncturing, and the blood vessel K
The indwelling needle 1 can be easily moved to an appropriate position in the blood vessel K without causing troubles such as penetrating the front wall and the rear wall of the blood vessel and damaging the blood vessel K by cutting the human body tissue. Can be detained.

Further, as shown in FIG.
Since the distance m4 between the tip 3e of the needle tip 3b and the tip 9b of the trocar 8 is formed short, the relatively thin blood vessel K
Can be easily detained at the appropriate position,
An indwelling needle 1 having a wide range of use can be obtained.

Embodiment 2 FIG. FIG. 5 is a top view, a sectional view, and a bottom view of a main part of the inner needle according to the second embodiment of the present invention. This embodiment is different from the inner needle 2 of the first embodiment in that the side hole 4 provided on the side wall of the needle tip 3b facing the jaw 3c is replaced with the side wall of the needle tip 3b on the jaw 3c side. A side hole 14 is provided in the base 11 of the first embodiment.
In place of the closing member 11 whose b side has been cut away, there is provided a closing member 15 formed so as to close from the distal end portion 14a side of the side hole 14 of the lumen 3a of the inner needle 2 to the needle tip 3b. . In addition, when the outer sleeve 9 of the outer sleeve 8 is attached to the inner needle 2, the distal end 9 b of the outer sleeve 9 is connected to the base 14 of the side hole 14.
The length is formed so as to substantially coincide with the b side or to cover a part of the side hole 14 on the base 14b side.

As shown in FIG. 5A, the side hole 14 of the inner needle 2 has a major axis located in the longitudinal direction of the inner needle 2, and as shown in FIG. The distance m5 between the portion 3c and the tip portion 14a of the side hole 14 is formed to be 2 mm or less, and it is desirable that the distance 3 is as close to the jaw portion 3c as possible from the viewpoint of processing.

The closing member 15 is made of the same metal material as the inner needle 2 similarly to the closing member 11 of the first embodiment.
As shown in (b), the inner needle 2 is inserted into the distal end side of the lumen 3a (the needle tip 3b side), and the distal end 15a side is inserted into the needle tip 3b.
The opening is closed in the same plane as the cutting edge surface 3d, and the base 15a side is formed so as to substantially coincide with the tip end 14a side of the side hole 14 or to be slightly located on the base 14b side.

The indwelling needle 1 according to this embodiment is
As in the case of the first embodiment, a side hole 14 is formed in a stainless steel pipe constituting the needle portion 3 of the inner needle 2 by a press punching method, and a column-shaped closing member 15 is inserted into the bore of the stainless steel pipe from the tip end of the stainless steel pipe. After the press-fitting, spot welding is performed, the needle tip 3b is cut so as to form the needle part 3, and the needle tip part 3b is processed into a solid needle shape by a processing machine. At this time, the distance m5 between the jaw 3c of the needle tip 3b and the tip 14a of the side hole 14 is adjusted to, for example, 1 mm. Then, the inner needle hub 5 is welded to the base side of the needle portion 3, and the indwelling needle 1 is constituted by the formed inner needle 2 and outer trocar 8.

With this configuration, substantially the same operations and effects as those of the first embodiment can be obtained. When flashback is confirmed by puncturing the indwelling needle 1 into the blood vessel K, as shown in FIG. In addition, not only the inner needle 2 but also the distal end 9b of the trocar 8 is surely located in the blood vessel K,
Unlike the case of using a conventional indwelling needle, there is no need to push the trocar a few millimeters further depending on the experience and intuition of the doctor. As a result, the indwelling needle 1, particularly the trocar 8, is
It becomes extremely easy to detain at an appropriate position in the inside, and there is no danger that repetition of the puncture operation or damage to the blood vessel wall or the like due to deep puncture may cause a serious crisis. In addition,
Since it is easier to secure a blood vessel, it is often used for a thick blood vessel K.

Further, since the closing member 15 has a simple structure, it can be easily formed, and the working of the inner needle 2 is easy, so that the indwelling needle 1 can be manufactured at low cost. The closing member 15 allows the needle tip 3b of the inner needle 2 to be formed in a solid needle shape, so that the indwelling needle 1 with low resistance at the time of puncturing and sharpness can be obtained.

In the above embodiment, the closing member 15 is made of a metal material. However, the closing member 15 may be made of a polymer material such as a polycarbonate resin. The indwelling needle 1 in this case has a side hole 14 formed by a grinder in a stainless steel pipe constituting the needle part 3 of the inner needle 2, and has an outer diameter slightly smaller than the inner diameter of the stainless steel pipe (lumen diameter of the needle part 3). After inserting the cylindrical closing member 15 into the bore of the stainless steel pipe from the tip direction, it is fixed with, for example, an epoxy adhesive or the like, and cut so that the needle part 3 is formed. Into a needle shape. At this time, the jaw 3c of the needle tip 3b and the tip 14a of the side hole 14
Is adjusted so that the distance m5 with the distance becomes 1 mm. Then, the inner needle hub 5 is welded to the base side of the needle portion 3 to form the formed inner needle 2.
And an outer trocar 8.

In the above-described embodiment, the case where the trocar 8 constituted by the trocar portion 9 and the trocar hub 10 connected to the other end of the outer robe portion 9 is described as an example.
For example, a cannula made of plastic in which the mantle portion and the mantle hub are integrally formed may be used. In this case, the same effect can be obtained.

Further, in the above-described embodiment, the case where the substantially elliptical side holes 4 and 14 are formed on the side wall of the needle portion 3 so that the major axis thereof is located in the longitudinal direction of the inner needle 2 has been described. The shape of each of the four needles 14 is not limited to this, and may be, for example, a polygonal shape such as a square shape or a circular shape. It may be located in the direction. In these cases, a similar effect is obtained.

[0035]

As described above, the indwelling needle according to the present invention has a lumen penetrating in the longitudinal direction, is provided with a needle tip part whose one end is obliquely cut, and is provided on the side wall near the needle tip part. A needle portion made of a metal material provided with a hole, and an inner needle formed by an inner needle hub made of plastic connected to the other end of the needle portion, and an inner needle having an inner diameter substantially equal to the outer diameter of the needle portion of the inner needle. Having a cavity,
An outer jacket made of plastic constituted by an outer jacket covering the needle section except for the needle tip side of the needle section, and an outer jacket hub provided at the other end of the outer jacket, and a needle tip of the needle section of the inner needle The indwelling needle is provided with a closing member made of a metal material or a synthetic resin material which is inserted into the side lumen so that the side hole can communicate with the lumen and closes the opening in the same plane as the blade surface of the needle tip. The shape of the distal end of the inner needle can be formed into a rounded needle shape by the closing member, and an indwelling needle with low resistance to human tissue at the time of puncturing and a sharp cutting can be obtained. Thereby, operability is improved, and a highly reliable indwelling needle can be obtained.

Further, in the indwelling needle according to the present invention, the side hole of the needle portion of the inner needle is formed such that a distance between a perpendicular line dropped from the jaw portion on the side wall facing the jaw portion of the needle tip and the center of the side hole is 3 mm. And the closing member is desirably within 1 mm, and the closing member is formed such that the base side of the needle tip which is opposed to the blade tip surface of the tip end side substantially coincides with the tip end side of the side hole or slightly has the base of the side hole. It is sloping obliquely upward toward the jaw side of the needle tip and cut off so as to form a blood flow path between the side hole and the indwelling needle. If the back is confirmed, not only the inner needle but also the trocar is located in the blood vessel, and depending on the experience and intuition of the physician's individual, as in the case of using a conventional indwelling needle, several millimeters more There is no need to push the trocar. Thereby, it becomes easy to indwell the indwelling needle, particularly the trocar, at an appropriate position in the blood vessel, and repeatedly perform the puncture work, or perform a deeper puncture than necessary to damage the blood vessel wall or important organs, Since there is no danger of causing a serious crisis, a highly reliable indwelling needle that can safely perform the operation can be obtained. In addition, even a relatively thin blood vessel can be easily indwelled at an appropriate position, and an indwelling needle having a wide use range can be obtained.

Further, in the indwelling needle according to the present invention, the distance between the jaw and the tip of the side hole is 2 mm or less on the side wall of the inner tip of the inner needle. And the closing member is formed such that the base side of the closing member substantially coincides with or is slightly located on the base side of the side hole, so that the indwelling needle, particularly the trocar, is inserted into the blood vessel. It is extremely easy to indwell at an appropriate position, and it is possible to obtain an indwelling needle that can be safely operated. In addition, since the closing member has a simple structure, it can be easily formed, and the inner needle can be easily worked. Therefore, an indwelling needle that can be manufactured at low cost can be obtained.

In the indwelling needle according to the present invention, when the outer sleeve of the outer needle is attached to the inner needle, the distal end of the outer sleeve does not protrude from the jaw of the needle tip and is substantially flush with the base of the side hole. It is formed so as to have a length corresponding to or covering a part of the base side of the side hole, and the length of the outer part of the trocar covering the side hole is set such that the distance between the tip of the outer part and the base side of the side hole is 2 mm. As described below, when flashback is confirmed, the trocar is surely positioned in the blood vessel, and repetition or failure of the puncture operation can be prevented, and the operation can be performed safely.

As described above, according to the present invention, an indwelling needle with high operability and high reliability which can be manufactured at low cost and which can be safely and easily indwelled in a patient can be obtained.

[Brief description of the drawings]

FIG. 1 is a top view, a cross-sectional view, and a bottom view of a main part of a first embodiment of the present invention.

FIG. 2 is a cross-sectional view and a XX cross-sectional view of a main part of the inner needle according to the first embodiment.

FIG. 3 is an explanatory diagram illustrating a configuration of a first embodiment of the present invention.

FIG. 4 is an operation explanatory view of the first embodiment of the present invention.

FIG. 5 is a top view, a sectional view, and a bottom view of a main part of an inner needle according to a second embodiment of the present invention.

FIG. 6 is an operation explanatory view of the second embodiment of the present invention.

FIG. 7 is an explanatory view of a configuration of a conventional indwelling needle and an enlarged sectional view of a main part thereof.

FIG. 8 is an operation explanatory view of a conventional indwelling needle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Indwelling needle 2 Inner needle 3 Needle part 3a Lumen 3b Needle tip 3c Jaw part 4,14 Side hole 5 Inner needle hub 8 Outer needle 9 Outer part 9a Inner cavity 9b Tip part 10 Outer needle hub 11,15 Closure member 12 Channel

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Nobutsu Kanie 5-27-7 Sendagaya, Shibuya-ku, Tokyo Nihon Brunswick Building 5th Floor Inside Nihon Sherwood Co., Ltd. (72) Inventor Norio Yasuda Sendagaya, Shibuya-ku, Tokyo 5-27-7 Nihon Brunswick Building 5F Nihon Sherwood Co., Ltd.

Claims (5)

[Claims] 1. A needle part made of a metal material having a bore penetrating in the longitudinal direction, having a needle tip part whose one end is cut obliquely, and having a side hole in a side wall near the needle tip part. And an inner needle constituted by an inner needle hub made of plastic connected to the other end of the needle portion, and a lumen having an inner diameter substantially equal to the outer diameter of the needle portion of the inner needle. An outer jacket made of plastic constituted by an outer jacket covering the needle section except for the needle tip side, and an outer trocar hub provided at the other end of the outer jacket, and a needle tip side of the needle section of the inner needle A closing member made of a metal material or a synthetic resin material that is inserted into the lumen so that the side hole can communicate with the lumen, and that closes the opening in the same plane as the blade tip surface of the needle tip. And indwelling needle. 2. A side hole of the needle portion of the inner needle is provided so that a distance between a perpendicular line dropped from the jaw portion on a side wall facing the jaw portion of the needle tip and a center of the side hole is within 3 mm, preferably 1 mm. And the closing member is formed such that the base side of the needle tip which is opposed to the blade end face of the tip end side substantially coincides with the tip end side of the side hole or slightly the base side of the side hole. 2. The indwelling device according to claim 1, wherein the needle tip portion is inclined obliquely upward toward the jaw portion side of the needle tip portion, and cut off so as to form a blood flow path between the needle tip portion and the side hole. needle. 3. A side hole of a needle portion of the inner needle is formed such that a distance between the jaw portion and a tip end side of the side hole is 2 mm or less on a side wall of the needle point portion on the jaw portion side. 2. The indwelling needle according to claim 1, wherein the closing member is formed such that a base side of the closing member substantially coincides with or is slightly located on a base side of the side hole. 4. When the outer sleeve of the outer needle is attached to the inner needle, the distal end of the outer sleeve does not protrude from the jaw of the needle tip, and substantially coincides with the base side of the side hole. The indwelling needle according to claim 1, wherein the indwelling needle is formed to have a length that covers a part of the base portion of the side hole. 5. The length of the jacket of the mantle covering the side hole is such that the distance between the tip of the mantle and the base of the side hole is 2 mm or less. Item 4
The indwelling needle described.