JP3723972B2 - Blood collection needle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a blood collection needle. More specifically, one end of the blood collection needle is punctured into a subject's blood vessel and the other end is communicated with the vacuum blood collection tube so that an amount of blood corresponding to the negative pressure in the vacuum blood collection tube can be collected. Related to the blood collection needle. According to the blood collection needle of the present invention, it is possible to confirm that one end has been punctured into the subject's vein before the other end communicates with the vacuum blood collection tube.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, when collecting blood with a vacuum blood collection tube, a blood collection needle has been proposed that can confirm a so-called flashback that the needle is securely punctured into a subject's vein before attaching the vacuum blood collection tube.
[0003]
As such a blood collection needle, for example, a substantially cylindrical hub, a needle tube having sharp tips extending from both axial ends of the hub, and one end of the needle tube are fitted to the hub. The hub is provided with a vent hole that allows the inside and outside of the elastic cap to communicate with each other, and an air-permeable blood-impermeable filter is provided at the outer opening of the vent hole. And blood collection needles (Japanese Patent Laid-Open No. 4-132541, Japanese Patent Laid-Open No. 4-364831, Japanese Patent Laid-Open No. 7-379, Japanese Patent Laid-Open No. 8-150134, etc.).
In order to confirm flashback, these blood collection needles allow the blood to flow outside while allowing the blood to flow into the blood collection needle when the blood collection needle is punctured into a subject's vein. An air permeable blood impermeable filter is provided so as not to leak outside. As the air permeable blood impermeable filter, a membrane filter or a sintered filter is used.
[0004]
However, the blood collection needles described in JP-A-4-132541, JP-A-7-379, and JP-A-8-150134 need to form a vent hole in the hub when the hub is molded. . In order to make the hub itself small, it is preferable to make the hole diameter as small as possible. Therefore, the structure of the hub naturally becomes complicated and it becomes difficult to form the hub.
In addition, when a membrane filter is used as the air permeable blood impermeable filter, the membrane filter is fragile. Therefore, when it 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 blood collection needle (Japanese Patent Laid-Open Nos. 4-132541, 4-3646481, 7-379, and 8) -150134) is provided with a filter in the outside opening of the ventilation hole or inside the ventilation hole having a large opening, so that the sintered filter absorbs moisture in the outside atmosphere and clogs. There is a risk of it happening.
[0005]
[Problems to be solved by the invention]
In view of the above circumstances, the present invention provides a blood collection needle that is free from the risk of filter breakage due to fusion, is free from the risk of clogging of the filter due to moisture in the external atmosphere, and has a simple hub structure and is easy to mold. There is.
[0006]
[Means for Solving the Problems]
As a result of various earnest studies to solve the above-mentioned problems, the present inventor used a hub composed of three members having a shape that allows air passages to be formed by gaps between the respective members when assembled. It has been found that the intended purpose can be achieved by providing a filter at an intermediate portion of the air passage, and the present invention has been achieved.
[0007]
That is, the present invention relates to a needle tube having a sharp cutting edge at the distal end and the proximal end, a hub externally attached to an intermediate portion of the needle tube, and airtightly attached to the proximal end side of the hub, A blood collecting needle having an elastic cap formed so as to accommodate the cutting edge of the blood vessel and capable of collecting blood by attaching a vacuum blood collecting tube and a holder for holding the same to the proximal end side, wherein the hub is a needle tube support member The holder connecting member and the elastic cap connecting member, and these members are assembled so as to form an air passage that communicates the inside of the elastic cap with the external atmosphere, and the air-permeable blood impermeability is provided at an intermediate portion of the air passage. A blood collection needle provided with a sex filter.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the 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. 1 is a cross-sectional view showing an 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. A blood collection needle 1 of the present invention is attached to a needle tube 2 having sharp cutting edges 21 and 22 at the distal end and proximal end, a hub 3 externally inserted in an intermediate portion of the needle tube 2, and a proximal end side of the hub 3. And an elastic cap 4.
In the blood collection needle 1 of the present invention, the distal end refers to the side that punctures the patient (left side in the figure), and the proximal end refers to the side that punctures the vacuum blood collection tube (not illustrated) (right side in the figure).
[0009]
The needle tube 2 in the present invention is a hollow tube, and sharp cutting edges 21 and 22 are formed at the distal end and the proximal end thereof. The cutting edge 21 has an inclined blade surface to reduce the piercing resistance when puncturing a vacuum blood collection tube.
Examples of the material of the needle tube 2 include metal materials such as stainless steel, aluminum, titanium, and alloys thereof.
[0010]
A hub 3 is externally inserted at an intermediate portion of the needle tube 2. The hub 3 is airtightly fixed to the needle tube 2 with, for example, an adhesive S at 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 includes three members, a needle tube support member 31, a holder connection member 32, and an elastic cap connection member 33. By assembling these members, an air passage that communicates the inside of the elastic cap with the external atmosphere is formed. Yes. All of the three members are hollow tubes and are formed by injection molding or the like. The three members are preferably made of a transparent or translucent material for easily confirming flashback. Specifically, polypropylene, polyethylene, polystyrene, polyethylene terephthalate, polymethylpentene, polycarbonate, polyacrylonitrile, Examples thereof include ABS resin. The three members are assembled by fitting, fusion with ultrasonic waves or heat, or an adhesive to form the hub 3.
[0011]
The needle tube support member 31 is formed such that the inner diameter of the smallest portion of its lumen is slightly larger than the outer diameter of the needle tube 2. The needle tube 2 is inserted into the lumen, and the needle tube 2 is hermetically 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.
2 is a cross-sectional view of the blood collection needle 1 shown in FIG. A rib 311 as shown in FIG. 2 may be provided on the outer periphery on the distal end side of the needle tube support member 31. The rib 311 is used to engage with a needle cap (not shown) to prevent the blood collection needle 1 from rotating within the needle cap.
[0012]
The holder connecting member 32 has a size that allows the elastic cap connecting member 33 to be inserted into its inner cavity, and its distal end is fixed to the proximal end of the needle tube support member 31. A screw part 321 is provided on the outer periphery on the proximal end side of the holder connecting member 32, and a mouth part of a holder (not shown) for holding a vacuum blood collection tube is screwed into the screw part 321. It has become.
[0013]
The elastic cap connecting member 33 has an inner diameter slightly larger than the outer diameter of the needle tube 2. A locking portion 331 is formed at the base end portion of the elastic cap connecting member 33, thereby locking the elastic cap 4 so that it cannot be detached airtightly.
FIG. 3A is a cross-sectional view taken along line BB of the blood collection needle 1 shown in FIG. As shown in FIG. 3A, it is preferable that at least a part of the holder connecting member 32 and the elastic cap connecting member 33 are fixed.
[0014]
The elastic cap 4 locked to the locking portion 331 of the elastic cap connecting member 33 has a bottomed cylindrical shape, can store the cutting edge 22 on the proximal end side of the needle tube 2, and is connected to the needle tube 2. It is formed in a size having a gap through which blood can pass. 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.
[0015]
As shown in FIG. 1, the needle tube support member 31, the holder connection member 32, and the elastic cap connection member 33 have shapes that form gaps 51, 52, 53, and 54 when assembled. The gaps 51, 52, 53, and 54 form a ventilation path for communicating the inside of the elastic cap 4 with the external atmosphere. The gap 51 is a gap between the elastic cap connection member 33 and the needle tube 2, the gap 52 is a gap between the needle tube support member 31 and the needle tube 2, and the gap 53 is the needle tube support member 31 and the holder connection member. 32 and the elastic cap connecting member 33, and the gap 54 is 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 in the entire outer periphery of the needle tube 2, or may be provided in a part thereof. For example, the gap 53 may be provided at two locations above and below the needle tube 2 as shown in FIG. Further, the gap 53 may be provided in the holder connecting member 32 as shown in FIG. 3A, or may be provided in the elastic cap connecting member 33 as shown in FIG. 3B. good.
[0016]
An air permeable blood impermeable filter 6 is provided at an intermediate portion of the ventilation path formed by the gaps 51, 52, 53 and 54 so as to block the ventilation path. The air permeable blood impermeable filter 6 is not particularly limited as long as it has pores that allow gas to pass but not liquid such as a membrane filter and a sintered filter, but preferably polyethylene, polypropylene, poly It is a sintered body made of methyl methacrylate, polystyrene, or the like, and more preferably contains a water-absorbing polymer that swells when contacted 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% with respect to the total weight of the sintered filter.
[0017]
The air permeable blood impermeable filter 6 is fixed in the air passage by fitting. The place to be fitted is not particularly limited as long as it is inside the air passage, but is preferably in the gap 53. For example, the air permeable blood impervious filter 6 is different from the blood collecting needle 1 shown in FIG. 1 by the holder connecting member 32 and the elastic cap connecting member 33, or in another embodiment of the blood collecting needle 1 shown in FIG. Are fitted by the needle tube support member 31, the holder connection member 32 and the elastic cap connection member 33. Therefore, even if the air-permeable blood-impermeable filter 6 is a membrane filter, there is no possibility of breakage because there is no need for fusing. If the air permeable blood impermeable filter 6 is a sintered filter, the shape thereof may be slightly larger than the gap 53, and the state before being brought into contact with blood by being press-fitted into the gap 53. In this case, it can be securely fixed in the gap.
The gaps 53 and 54 have a very small diameter and have a long overall length, so that moisture in the external atmosphere is difficult 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 by moisture in the external atmosphere.
[0018]
As shown in FIGS. 1 and 4, the gap 53 that forms the ventilation path may be formed with 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 more preferable because it can secure a sufficient thickness that does not leak the blood flowing into the blood collection needle 1 by flashback.
[0019]
The blood collection needle 1 of the present invention is used by piercing the patient's vein with the cutting edge 21 at the tip of the needle tube 2 in a state in which a holder (not shown) is screwed into the screw portion 321 of the holder connecting member 32. 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, the blood flows into the gaps 51 and 52 and is clogged by the air permeable blood impermeable filter 6. The flashback composed of such a mechanism can be confirmed from the outside in 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 the cutting edge 22 at the proximal end of the needle tube 2 is punctured with a rubber stopper provided at the mouth of the vacuum blood collection tube. By being inserted into the blood collection tube, blood flows into the vacuum blood collection tube to collect blood.
[0020]
【The invention's effect】
The blood collection needle of the present invention forms a ventilation path communicating with the external atmosphere by assembling three members of the hub, so that it is not necessary to form a ventilation path inside the hub itself, and its molding is easy. . In addition, since the air permeable blood impermeable filter is fitted between the members during assembly, there is no possibility of being damaged by fusing the filter. In addition, since the air passage extending from the air permeable blood impermeable filter provided in the middle portion of the air passage to the external atmosphere and the external opening of the air passage 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 an embodiment of a blood collection needle of the present invention.
FIG. 2 is a cross-sectional view 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 the line BB.
FIG. 4 is a cross-sectional view showing another embodiment of the blood collection needle of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Blood collection needle 2 Needle tube 21, 22 Cutting edge 3 Hub 31 Needle tube support member 32 Holder connection member 33 Elastic cap connection member 4 Elastic cap 6 Air-permeable blood impermeable filter

Claims (5)

A needle tube having a sharp cutting edge at the distal end and the proximal end, a hub externally inserted in an intermediate portion of the needle tube, and a hermetically attached to the proximal end side of the hub, and storing the cutting edge on the proximal end side of the needle tube In the blood collecting needle that has an elastic cap formed as described above and can collect blood by attaching a vacuum blood collection tube and a holder for holding the same to the proximal end side, the hub includes a needle tube support member, a holder connecting member, and It consists of elastic cap connection members, and these members are assembled so as to form an air passage that communicates the inside of the elastic cap with the external atmosphere,
The air in the needle tube is allowed to escape through an air permeable blood impermeable filter through a gap formed between the outside of the elastic cap connecting member and the inside of the holder connecting member. A permeable filter is provided,
A gap between the needle tube support member and the needle tube constituting a part of the ventilation path is formed on the distal end side of the needle tube with respect to the air permeable blood impermeable filter,
The gap between the needle tube support member and the needle tube is connected to the proximal end of the needle tube by the air passage without being blocked by the air permeable blood impermeable filter,
The needle tube support member is provided closer to the distal end side of the needle tube than the holder connecting member.
The blood collection needle, wherein the needle tube support member is transparent or translucent . A space inside the elastic cap is connected to a gap between the needle tube support member and the needle tube via a gap between the elastic cap connection member and the needle tube, and a gap between the needle tube support member and the needle tube is connected to the holder connection member. And forming the ventilation path by connecting to the gap between the holder connection member and the elastic cap through the gap between the elastic cap connection member and the elastic cap connection member,
The air permeable blood impermeable filter is interposed between a gap between the needle tube support member and the needle tube and a gap between the holder connection member and the elastic cap connection member,
The blood collection needle according to claim 1 , wherein the air inside the elastic cap can be exhausted to the outside through the ventilation path . The blood collecting needle according to claim 1 or 2, wherein the air permeable blood impermeable filter is fitted and fixed between the holder connecting member and an elastic cap connecting member. The needle tube support member, the holder connection member, and the elastic cap connection member are transparent or translucent.
The blood collection needle according to any one of claims 1 to 3, wherein The ventilation path is a gap between the elastic cap connection member and the needle tube, a gap between the needle tube support member and the needle tube, a gap between the holder connection member and the elastic cap connection member, and the holder connection member and the elastic cap. And a gap between
The air permeable blood impermeable filter is connected to an external atmosphere via a gap between the holder connecting member and the elastic cap, and a gap between the holder connecting member and the elastic cap connecting member;
The gap between the holder connecting member and the elastic cap and the gap between the holder connecting member and the elastic cap connecting member communicate with each other by forming a substantially right angle in the longitudinal section.
The blood collection needle according to any one of claims 1 to 4.

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