JP2001299728A - Blood drawing needle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blood drawing needle in which both a membrane filter and a sintered filter can be used without any problem as air-permeable and blood in-permeable filters and which is easily molded. SOLUTION: In the blood drawing needle 1 in which a needle pipe 2 with sharp edges on the apex point and the base end, a hub 3 inserted outside at the middle site of the needle pipe 2 and an elastic cap 4 fitted on the base end side of the hub 3 and formed so as to store the edge 22 of the base end side are provided and drawing of blood can be performed by fitting a vacuum blood drawing pipe and a holder on the base end side, the above described hub 3 consists of a needle pipe holding member 31, a holder connecting member 32 and an elastic cap connecting member 33 and these members are assembled in such a way that an air passage consisting of gaps 51, 52, 53 and 54 for communicating the inside of the elastic cap 4 with the outside atmosphere is formed and the air-permeable and blood in permeable filter 6 is provided at the middle site of the above described air passage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood collection needle, and more particularly, to puncture one end of a blood vessel of a subject and connect the other end to a vacuum blood collection tube to respond to a negative pressure in the vacuum blood collection tube. The present invention relates to a blood collection needle capable of collecting an amount of blood. According to the blood collection needle of the present invention, it is possible to confirm that one end has been punctured into the vein of the subject before the other end communicates with the vacuum blood collection tube.

[0002]

2. Description of the Related Art Conventionally, a blood collection needle has been proposed which can confirm that a needle is securely punctured into a vein of a subject, that is, a so-called flashback, before attaching the vacuum blood collection tube when blood is collected by a vacuum blood collection tube. ing.

[0003] As such a blood collection needle, for example, a substantially cylindrical hub, a needle tube having a sharp tip extending from both ends in the axial direction of the hub, and a hub attached to the hub so as to surround one end of the needle tube. It consists of a bottomed tubular elastic cap fitted,
A blood collection needle provided with a vent hole for communicating the inside and the outside of the elastic cap with the hub, and an air-permeable blood-impermeable filter provided at an outside opening of the vent hole (Japanese Patent Laid-Open No. 4-1 / 1991).
No. 32541, JP-A-4-364831, JP-A-7-379, JP-A-8-150134, and the like. In order to confirm flashback, these blood collection needles allow air to escape to the outside so that blood flows into the blood collection needle when the blood collection needle is punctured into a vein of a subject, An air-permeable blood-impermeable filter is provided to prevent leakage to the outside. As the air permeable blood impermeable filter, a membrane filter, a sintered filter, or the like is used.

[0004] However, Japanese Patent Application Laid-Open No. 4-132541,
JP-A-7-379 and JP-A-8-150134
In the blood collection needle described in Japanese Patent Application Laid-Open Publication No. H11-157, it is necessary to form a ventilation hole inside the hub when the hub is formed. In order to reduce the size of the hub itself, it is preferable to form the vent hole as small as possible, so that the structure of the hub naturally becomes complicated and molding becomes difficult. Further, when a membrane filter is used as the air-permeable blood-impermeable filter, the membrane filter is easily broken, and if the membrane filter is fixed to the hub by fusion, the filter may be damaged. Further, when a sintered filter is used as the air-permeable blood-impermeable filter, the above-mentioned blood collection needle (JP-A-4-132541, JP-A-4-3541) is used.
No. 64831, JP-A-7-379, JP-A-8
No. -150134), the filter is provided in the outer opening of the vent or the inside of the vent which is largely opened, so that the sintered filter absorbs the moisture in the external atmosphere and causes clogging. May cause.

[0005]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention has no risk of damage to the filter due to fusion, no risk of clogging of the filter due to moisture in the external atmosphere, and has a simple hub structure. An object of the present invention is to provide a blood collection needle that can be easily formed.

[0006]

The inventor of the present invention has made various studies to solve the above-mentioned problems. As a result, three members having a shape such that a ventilation path can be formed by a gap between respective members when assembled are obtained. The present inventors have found that the intended purpose is achieved by using a hub made of and providing a filter at an intermediate portion of the air passage of the hub, and arrived at the present invention.

That is, the present invention provides a needle tube having a sharp cutting edge at a distal end and a proximal end, a hub externally inserted at an intermediate portion of the needle tube, and a hermetically attached to a proximal end side of the hub. An elastic cap formed to house the cutting edge on the proximal end side, and a blood collection needle capable of performing blood collection by attaching a vacuum blood collection tube and a holder for holding the blood collection tube on the base end side, wherein the hub is A needle tube supporting member, a holder connecting member, and an elastic cap connecting member. These members are assembled so as to form a ventilation path for communicating the inside of the elastic cap with an external atmosphere. A blood collection needle provided with a blood impermeable filter.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a blood collection needle of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings, but the present invention is not limited to these descriptions. FIG.
Is a cross-sectional view showing one embodiment of the blood collection needle of the present invention, and FIG. 4 is a cross-sectional view showing another embodiment of the blood collection needle of the present invention. The blood collection needle 1 of the present invention is attached to a needle tube 2 having sharp cutting edges 21 and 22 at a distal end and a proximal end, a hub 3 externally inserted at an intermediate portion of the needle tube 2, and a proximal end side of the hub 3. Elastic cap 4. In the blood collection needle 1 of the present invention, the distal end refers to the side that punctures the patient (the left side in the figure), and the proximal end refers to the side that punctures the vacuum blood collection tube (not shown) (the right side in the figure).

The needle tube 2 in the present invention is a hollow tube,
Sharp cutting edges 21 and 22 are formed at the distal end and the proximal end. The cutting edge 21 has a sloped cutting surface for the patient, and the cutting edge 22 has an inclined cutting surface in order to reduce the penetration resistance when puncturing the vacuum blood collection tube. Examples of the material for the needle tube 2 include metal materials such as stainless steel, aluminum, titanium, and alloys thereof.

A hub 3 is externally inserted at an intermediate portion of the needle tube 2. The hub 3 is air-tightly fixed to the needle tube 2 by, for example, an adhesive S on the distal end side of the hub 3. As the adhesive S, an epoxy curing agent, a UV curing adhesive, or the like is used. The hub 3 is composed of three members: a needle tube support member 31, a holder connection member 32, and an elastic cap connection member 33. By assembling these members, a ventilation path for communicating the inside of the elastic cap with an external atmosphere is formed. I have. Each of the three members is a hollow tube, and is formed by injection molding or the like. For the three members, a transparent or translucent material is preferably used in order to easily confirm flashback, and specifically, polypropylene, polyethylene, polystyrene, polyethylene terephthalate, polymethylpentene, polycarbonate, polyacrylonitrile, ABS
Resins. The three members are assembled by fitting, fusion by ultrasonic waves or heat, or an adhesive to form the hub 3.

The needle tube supporting member 31 is formed such that the inner diameter of the smallest portion of the lumen is slightly larger than the outer diameter of the needle tube 2. The needle tube 2 is provided in the lumen.
Is inserted, and the needle tube 2 is air-tightly fixed to the needle tube support member 31 with an adhesive S on the distal end side of the needle tube support member 31. The adhesive S may be used to fill a part of the gap between the needle tube support member 31 and the needle tube 2 as shown in FIG. FIG. 2 is a sectional view of the blood collection needle 1 shown in FIG.
It is a line sectional view. A rib 311 as shown in FIG. 2 may be provided on the distal end side outer periphery of the needle tube supporting member 31. The rib 311 is used to engage with a needle cap (not shown) to prevent the blood collection needle 1 from rotating in the needle cap.

The holder connecting member 32 has such a size that the inner cavity can receive the elastic cap connecting member 33,
The distal end is fixed to the proximal end of the needle tube support member 31. A screw portion 321 is provided on the base end side outer periphery of the holder connection member 32, and an opening of a holder (not shown) for holding a vacuum blood collection tube is screwed into the screw portion 321. It has become.

The elastic cap connecting member 33 has an inner diameter slightly larger than the outer diameter of the needle tube 2. At the base end of the elastic cap connecting member 33, a locking portion 33 is provided.
The elastic cap 4 is hermetically sealed so as not to be detached. FIG. 3 (a)
FIG. 2 is a sectional view taken along the line BB of the blood collection needle 1 shown in FIG. 1. FIG.
(A), it is preferable that at least a part of the holder connection member 32 and the elastic cap connection member 33 are fixed.

The locking portion 3 of the elastic cap connecting member 33
The elastic cap 4 locked to the base 31 has a cylindrical shape with a bottom, and can accommodate the cutting edge 22 on the proximal end side of the needle tube 2, and has a gap through which blood can pass between the elastic tube 4 and the needle tube 2. It is formed in the size which has. Examples of the material of the elastic cap 4 include natural rubber, synthetic rubber such as isoprene rubber and silicon rubber, and elastomer. Further, the elastic cap 4 may be transparent or translucent so that flashback can be easily confirmed.

The needle tube supporting member 31, the holder connecting member 3
2 and the elastic cap connecting member 33 are provided with gaps 51, 52, 53 and 54 when assembled as shown in FIG.
Are formed so that the gaps 51 and 5 are formed.
2, 53 and 54 form an air passage for communicating the inside of the elastic cap 4 with the outside atmosphere. The gap 51
Is a gap between the elastic cap connecting member 33 and the needle tube 2, the gap 52 is a gap between the needle tube supporting member 31 and the needle tube 2, and the gap 53 is a gap between the needle tube supporting member 31 and the holder connecting member 32. The gap 54 is a gap provided between the holder connecting member 32 and the elastic cap 4 and communicates with the external atmosphere. The gaps 51, 52, 53 and 54 may be provided on the entire outer periphery of the needle tube 2, or may be provided on a part thereof. For example, the gap 53 is shown in FIG.
As shown in the above, two portions may be provided above and below the needle tube 2. The gap 53 may be provided in the holder connecting member 32 as shown in FIG.
(B), the elastic cap connecting member 33 may be provided.

An air-permeable blood-impermeable filter 6 is provided at an intermediate portion of the air passage formed by the gaps 51, 52, 53 and 54 so as to block the air passage. The air-permeable blood-impermeable filter 6 is not particularly limited as long as it has a pore that allows gas to pass therethrough and does not allow liquid to pass therethrough, such as a membrane filter or a sintered filter. It is a sintered body made of methyl methacrylate, polystyrene, or the like, and more preferably contains a water-absorbing polymer that swells when it comes into contact with blood and closes the pores of the sintered body. Examples of the water-absorbing polymer include starch and acrylate, and the content thereof is preferably 5 to 30% based on the total weight of the sintered filter.

The air-permeable blood-impermeable filter 6
Is fixed in the ventilation path by fitting. The place to be fitted is not particularly limited as long as it is inside the ventilation path,
Preferably, it is in the gap 53. For example, in the blood collection needle 1 shown in FIG. 1, the air-permeable blood-impermeable filter 6 includes a holder connecting member 32 and an elastic cap connecting member 33.
In another embodiment of the blood collection needle 1 shown in FIG. 4, the needle tube support member 31, the holder connection member 32 and the elastic cap connection member 33 are fitted. Therefore, even if the air-permeable blood-impermeable filter 6 is a membrane filter, there is no need to fuse it, and there is no risk of damage. If the air-permeable blood-impermeable filter 6 is a sintered filter, its shape may be slightly larger than the gap 53.
By press-fitting into the gap 3, it can be firmly fixed to the gap even before contact with blood. Further, since the gaps 53 and 54 have a very small diameter and a long overall length, it is difficult for moisture in the external atmosphere to enter. Therefore, even if the air-permeable blood-impermeable filter 6 is a sintered filter, there is no possibility that the pores are clogged with moisture in the external atmosphere.

As shown in FIGS. 1 and 4, the gap 53 forming the air passage may have a large diameter only at a portion where the air-permeable blood-impermeable filter 6 is fixed. In this case, the air-permeable blood-impermeable filter 6 is used to flush the blood collection needle 1 by flashback.
It is more preferable because a sufficient thickness can be ensured so that blood flowing into the inside does not leak outside.

The blood collection needle 1 of the present invention comprises a holder connecting member 32.
In a state where a holder (not shown) is screwed into the screw portion 321 of the above, the cutting edge 21 of the distal end of the needle tube 2 is used by puncturing the vein of the patient. At this time, the air in the needle tube 2 escapes from the gap 54 to the outside through the ventilation path (gap 51 to 54), and blood flows into the needle tube 2. After the blood fills the elastic cap 4, it flows into the gaps 51 and 52 and is blocked by the air-permeable blood-impermeable filter 6. The flashback having such a mechanism can be externally confirmed on the elastic cap 4 or the hub 3. After confirming the flashback, a vacuum blood collection tube (not shown) is inserted into the holder, and a cutting edge 2 at the base end of the needle tube 2 is inserted.
2 is inserted into the vacuum blood collection tube by piercing a rubber stopper provided at the mouth of the vacuum blood collection tube, whereby blood flows into the vacuum blood collection tube and blood is collected.

[0020]

According to the blood collection needle of the present invention, since the hub assembles the three members to form an air passage communicating with the outside atmosphere, it is not necessary to form an air passage inside the hub itself. Easy to mold. In addition, since the air-permeable blood-impermeable filter is fitted between the members when assembling, there is no possibility that the filter will be damaged by fusing. In addition, since the air passage and the external opening of the air passage extending from the air-permeable blood-impermeable filter provided in the middle portion of the air passage to the external atmosphere have a very small diameter, the filter is formed by moisture in the external atmosphere. There is no risk of clogging.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a blood collection needle of the present invention.

FIG. 2 is a cross-sectional view taken along line AA of the blood collection needle shown in FIG.

FIG. 3 is a cross-sectional view of the blood collection needle shown in FIG. 1 taken along line BB.

FIG. 4 is a sectional view showing another embodiment of the blood collection needle of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Blood-collecting needle 2 Needle tube 21, 22 Cutting edge 3 Hub 31 Needle tube support member 32 Holder connecting member 33 Elastic cap connecting member 4 Elastic cap 6 Air-permeable blood-impermeable filter

Claims (3)

[Claims] 1. A needle tube having a sharp cutting edge at a distal end and a proximal end, a hub externally inserted at an intermediate portion of the needle tube, and a hermetically attached to a proximal end side of the hub, the proximal end side of the needle tube An elastic cap formed to house the cutting edge of
In a blood collection needle capable of performing blood collection by attaching a vacuum blood collection tube and a holder for holding the vacuum blood collection tube to the proximal end side, the hub includes a needle tube support member, a holder connection member, and an elastic cap connection member, and these members are elastic. A blood collection needle which is assembled so as to form a ventilation path for communicating the inside of the cap with an external atmosphere, and wherein an air-permeable blood-impermeable filter is provided at an intermediate portion of the ventilation path. 2. The air passage includes a gap between the elastic cap connecting member and the needle tube, a gap between the needle tube supporting member and the needle tube, a gap between the needle tube supporting member and the holder connecting member and the elastic cap connecting member, and a gap between the holder connecting member and the elastic tube. 2. A gap provided between the cap and the outside atmosphere.
The blood collection needle as described. 3. The blood collection needle according to claim 2, wherein the air-permeable blood-impermeable filter is provided in a gap between the needle tube support member, the holder connection member, and the elastic cap connection member.