JPH04132541A - Blood sampling needle - Google Patents

Abstract

PURPOSE:To enable the checking of flash back accurately with a simple construction by arranging a breathing filter which has an axial communicating hole which allows a hub to insert a canula, an air hole to make an internal cavity of a bottomed elastic chip communicate with an external atmosphere and a pore adapted to transmit gas but none of liquid. CONSTITUTION:When blood is sampled, canulas 41 and 45 are fastened with respective adhesives or the like as being inserted into a communicating hole 13. A thread part 15 provided on an outer circumference of a hub 10 of a blood sampling needle 1 is screwed down at a mouth part of a holder 200 to integrate the needle and the holder 200. In such a condition, when the canula 41 of the needle is stuck into a blood vessel V, blood in the blood vessel V flows into an internal cavity E of an elastic chip 50 via an internal hole of the canula 45 from the internal hole of the canula 41. It further rises to the inside of an air hole 19 and stops at a breathing filter 7. Here, at least one of the elastic chips 50 of the hub 10 is made of transparent or semi-transparent material beforehand thereby facilitating the checking of a flash back.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides a blood collection needle, in particular, a blood collection needle that communicates a single specimen source with a pre-depressurized specimen storage chamber - or multiple specimen collections. Concerning blood collection needles that are conditioned.

[Conventional technology]

BACKGROUND OF THE INVENTION Conventionally, in performing clinical tests, blood sampling units that allow blood sampling multiple times with a single puncture are frequently used. For example, as shown in FIG. 5, this unit includes a blood collection needle 100 equipped with cannulas 120 and 130 provided at both ends of a hub 110, an elastic tip attached to surround the cannula 130, and It is composed of a cylindrical holder 200 to which the needle 100 is fixed, and a blood collection tube 300 which is inserted into the holder 200 and whose pressure is removed in advance. When collecting blood, first, the holder 200 and the blood collection needle 100 are assembled in advance and integrated, and the cannula 120 side is punctured into the venous blood vessel to secure the venous blood vessel. Thereafter, blood collection is started by pushing the blood collection tube 300 into the holder and penetrating the rubber stopper 310 with the cannula 130, and the blood collection is completed in a state where the pressure inside the blood collection tube 300 and the venous pressure are balanced.

However, in such conventional vacuum blood sampling systems, there is no place for the gas inside the cannula and the elastic tip to escape during venipuncture, making it impossible to confirm so-called flashback. Therefore, there is sometimes a risk that blood collection may be started while the cannula is still inside the body after being dislodged from the vein.

In order to solve such problems, the
No. 9 has already proposed a needle assembly equipped with a mechanism for confirming flashback.

[Problem to be solved by the invention]

However, this device has a structure such as an aeration device as a communication path provided inside the hub, and a compressed annular sleeve inserted into the communication path in the device and having material properties that swell with moisture. The problem is that it is extremely complex and cannot be mass-produced at low cost. Further, in this case, when blood is collected, pressure is removed from the sleeve housed in the housing chamber, resulting in insufficient sealing with the outside, resulting in a lack of safety. Also, there is a lot of dead volume.

The present invention has been made to solve the above problems, and its purpose is to provide a blood collection needle that has an extremely simple configuration and has a mechanism that allows flashback to be confirmed reliably.

[Means to solve the problem]

In order to solve such problems, the present invention provides a substantially cylindrical hub, a cannula that extends from both axial ends of the hub and has a sharp tip with a communicating internal passage, and one of the cannula. a bottomed cylindrical elastic tip that is liquid-tightly fitted to the hub so as to surround the extending end of the cannula; the hub has an axial communication hole for inserting and fixing the cannula; A vent hole that communicates the inner cavity of the bottomed cylindrical elastic chip with the outside atmosphere, and a breathable filter that is fixed to the external opening of the vent hole and has pores that allow gas to pass through but not liquid. It was configured to have the following.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, the first embodiment of the blood collection needle of the present invention will be described based on FIG.

The blood collection needle 1 of the present invention includes a substantially cylindrical hub 10, and the hub 1.
Cannula 41.45 extending from both axial ends of 0
and a bottomed cylindrical elastic tip 50 fitted to one end of the hub 10 so as to surround one extending end of the cannula 45.
It has

The hub 10 has a substantially cylindrical shape, and has a communication hole 13 penetrated in the central axis direction and a communication hole E for communicating the inner cavity E of the bottomed cylindrical elastic tip 50 with the external atmosphere. It has pores 19.

The communication hole 13 is a hole for inserting and fixing the cannula 41, 45, and has an inner diameter slightly larger than the outer diameter of the cannula 41, 45. Usually, the difference in diameter of the cannula is about 0 to 0.3 m.

The ventilation hole 19 has one end 19a located at the rear end of the hub 10 and is installed so as to communicate with the inner cavity E of the elastic chip 50, and the other end 19b of the ventilation hole 19 is located so as to communicate with the external atmosphere. For example, it is installed on the outer periphery of the body of the hub 10. That is, in this embodiment, the ventilation hole 19 has a diameter of 1.9 mm at one end with a certain partition wall 21 separating the axial communication hole 13.
After being drilled for a predetermined length in the axial direction from a, the hole is turned in the outer circumferential direction and drilled outside.

The cross-sectional shape of the ventilation hole 19 is usually circular, but is not limited to this, and various shapes can be adopted. Vent hole 19
The diameter is about 0.2 to 2 m.

The other end 19 of such a ventilation hole 19 communicates with the external atmosphere.
The air-permeable filter 7 is attached to b by ultrasonic fusion, heat fusion, or the like. This breathable filter 7 has pores that allow gases to pass through but not liquids, and should preferably be water repellent and made of fluorine-based resin such as Teflon or olefin-based resin such as PP or PE. Contains resin.

Further, the hub 10 is provided with a threaded portion 15 on the outer periphery of the approximately central portion of the main body, and the mouth portion of a holder 200, which is one unit of the blood collection unit, is screwed into this threaded portion 15. . Furthermore, a locking portion 17 for locking the elastic tip 50 is formed at the rear end of the hub 10. The locking portion 17 is not particularly limited as long as it has a shape that prevents the elastic tip 50 from easily detaching. We are prepared.

The elastic tip 50 engaged with such a locking portion has a cylindrical shape with a bottom portion 51, and has a lumen portion E as a space surrounding the extending end of one cannula 45. The elastic tip 50 is required to have a certain degree of elasticity so that it can be resealed even after it is temporarily perforated by the cannula 45, especially for blood collection. Examples of the material used include synthetic rubber and elastomer. Among these, those having transparent or semi-transparent properties are preferred so that flashback can be confirmed. The dimensions of such an elastic tip are usually about 10 to 30 m in length and about 1 to 3 m in outer diameter.

Incidentally, the sharp tip of the cannula 41 and the sharp tip of the cannula 45 inserted into the communication hole 13 of the hub 10 are used as a sample source such as blood in a venous blood vessel and a so-called vacuum sampling source, respectively, when collecting a sample. A specimen storage chamber such as a blood vessel is punctured. Cannula 41 and cannula 45 may be separate bodies, or may be continuous/integrated. The cannula 41, 45 is inserted into the communication hole 13 and fixed with various adhesives or the like. Note that normally the hub 10
is usually formed by injection molding, and is preferably made of a transparent or translucent material in order to facilitate confirmation of flashback. Specific examples include resin materials such as polypropylene, polyethylene, polystyrene, polyethylene terephthalate, polymethylpentene, polycarbonate, polyacrylonitrile, and ABS. The dimensions of the hub 10 are approximately 10 to 30Wm in length and 5 to 15III in outer diameter.

Next, a second embodiment of the blood collection needle of the present invention will be described based on Figure 2.

The blood sampling needle 2 of the second embodiment is fundamentally different from that of the first embodiment in the configuration of the ventilation hole formed inside the hub. That is, the ventilation hole 69 of the second embodiment includes a portion thereof,
In particular, the axially bored portion is formed to be connected to the axial communication hole 63. Therefore, when the cannula is inserted into the communication hole 63, a part of the outer circumference of the cannula forms part of the communication hole 69.

With such a configuration, the outer diameter of the locking portion 67 for locking the elastic tip 50 can be reduced, and the communicating hole can be easily formed by injection molding.

[Operations and effects of the present invention]

The operation of the blood sampling needle of the present invention described above will be explained.

As shown in FIG. 3, the threaded portion 15 provided on the outer periphery of the hub 10 of the blood collection needle 1 is screwed into the opening of the holder 200, so that the blood collection needle and the holder 200 are integrated. In this state, the first cannula 41 of the blood collection needle is punctured into the blood vessel V. Then, the blood in the blood vessel V flows from the inner hole of the cannula 41 to the inner hole of the cannula 45, flows into the inner hole E of the elastic tip, and further rises into the inside of the ventilation hole, passing through the air permeable filter filter. Stop at. At this time, the hub 10 and the elastic tip 50
By forming at least one of the transparent or semi-transparent materials, flashbacks can be easily confirmed.

When the present inventors actually conducted an experiment to confirm flashback, flashback was confirmed even at a relatively low venous pressure of 5 an aq. In other words, the blood sampling needle of the present invention has an extremely simple configuration and has the effect that flashback can be confirmed reliably.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view of a blood sampling needle as a first embodiment of the present invention, FIG. 2 is a partial sectional view of a blood sampling needle as a second embodiment of the invention, and FIG. 3 is a partial sectional view of a blood sampling needle of the present invention. FIG. 4 is a schematic diagram for explaining the operation, FIG. 4 is a sectional view for explaining the state during blood collection, and FIG. 5 is an exploded perspective view of the blood collection unit. 1.2... Blood collection needle, 7... Breathable filter, 10.
60...Hub, 13.63...Communication hole, 19.69
...Vent hole, 41...First cannula, 45...Second cannula, 50...Elastic tip, E...Inner cavity. Applicant's agent Yasushi Ishikawa Younger brother Figure 3 Figure 4

Claims (1)

[Claims] 1. A substantially cylindrical hub, a cannula extending from both axial ends of the hub and each having a sharp tip with an internal passage communicating with the cannula, and surrounding one of the extending ends of the cannula. a bottomed cylindrical elastic tip that is fluid-tightly fitted to the hub, the hub has an axial communication hole for inserting and fixing the cannula, and the bottomed cylindrical elastic tip. It is characterized by comprising a vent hole that communicates the inner cavity of the chip with the outside atmosphere, and a breathable filter that is fixed to the external opening of the vent hole and has pores that allow gas to pass through but not liquid. Blood collection needle. 2. The blood collection needle according to claim 1, wherein at least one of the hub and the elastic tip is made of a transparent or semitransparent material. 3. The blood collection needle according to claim 1 or 2, wherein a part of the ventilation hole is formed to be connected to the axial communication hole. 4. The blood collection needle according to claim 1 or 2, wherein the ventilation hole is formed by providing a certain partition wall with the axial communication hole. 5. The blood collection needle according to any one of claims 1 to 4, wherein the breathable filter contains a fluorine resin or an olefin resin.