JPH0119963Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement in the shape of the tip of an indwelling needle.

It is well known that an indwelling needle generally consists of a flexible outer needle 1 and a rigid inner needle 2 made of metal or the like that is slidably inserted into the outer needle, as shown in FIG. ing.

Generally, the inner needle tip 3 of this indwelling needle protrudes from the outer needle tip, and there is a step 5 between the outer needle surface and the inner needle 2.
As a result, when puncturing a blood vessel, the penetration resistance increases when moving from the inner needle to the outer needle, causing pain to the patient. In addition, if there is the step 5 mentioned above, there is a risk that the tip of the flexible outer needle will turn over during puncture, and to prevent this, the outer needle must be made thicker to some extent, which increases the penetration resistance and This resulted in increased suffering. In addition, conventional indwelling needles have been seen in which a groove is formed near the tip of the inner needle, and the tip of the outer needle is inserted into this groove, but these grooves are separate from the tip of the inner needle. Pain is felt twice: when the tip of the inner needle penetrates the blood vessel, and when the tip of the outer needle reaches the puncture opening of the blood vessel and pushes the puncture opening open. Moreover, in conventional models, the entire circumferential direction of the outer needle tip is engaged in the groove of the inner needle, so if the outer needle tip has a narrow shape, it is difficult to remove the inner needle after puncturing. When you pull it out,
There is also a concern that the leading edge of the outer needle may get caught on the needle tip side edge of the inner needle groove, causing the outer needle tip to turn inward or not be able to be pulled out smoothly.

The present invention was devised to improve these conventional disadvantages, and includes a flexible outer needle,
In an indwelling needle consisting of a rigid inner needle that is slidably inserted into the outer needle, a groove portion having a concave curved cross section is formed in the circumferential direction at a position in contact with the main bevel portion of the tip of the inner needle, and The basic feature is that the tip of the outer needle has a constricted shape and that the tip of the outer needle is inserted into the inner needle groove.

An embodiment of the present invention will be described below with reference to the accompanying drawings. First, in FIG. 1, 1 is a flexible outer needle;
Reference numeral 2 denotes a rigid inner needle made of metal or the like that is slidably inserted into the outer needle, and the tip of the inner needle 2 is inserted into the outer needle 1.
It is now in a slightly more protruding state.

Furthermore, a groove 6 is formed at the tip of the inner needle 2, as shown in the enlarged view of FIG. This groove portion 6 is formed in the circumferential direction at a position in contact with the main bevel portion 7 of the inner needle 2, and has a concavely curved cross-sectional shape. Furthermore, the tip 4 of the outer needle is tapered inward, and is adapted to be inserted into the groove 6.

In the present invention, the thickness of the outer needle 1, the depth of the grooves 3, 3a, etc. are selected so that the distal end of the outer needle tip 4 is equal to or smaller than the outer shape of the inner needle in all embodiments. Further, the inner needle 2 may be hollow or bar-shaped.

The indwelling needle as explained above has an inner needle 2 and an outer needle 1.
The inner needle 2 is inserted into the patient's blood vessel, and then the inner needle 2 is pulled out.According to the present invention,
Since the groove 6 is formed at the tip of the inner needle and the outer needle tip 4 is inserted into the groove 6, there is no difference in level between the outer needle tip and the inner needle as in the conventional case.

Therefore, at the time of puncturing, when the inner needle 2 moves to the outer needle 1, the penetration resistance is reduced, so the pain to the patient can be reduced, and since the distal end of the outer needle is inside the groove, There is no need to worry about the tip of the outer needle turning over during puncture, and the associated pain and blood vessel damage to the patient can also be prevented. Furthermore, according to the present invention, since the above-mentioned concerns about curling and the like are eliminated, the thickness of the outer needle 1 can be made thinner, the penetration resistance is reduced, and the pain is alleviated. Furthermore, since the groove part 6 of the present invention is formed so as to be in contact with the main bevel part 7, the outer needle tip part 4 is inserted into the blood vessel at the same time as the blood vessel is incised by the blade of the inner needle tip, causing pain. can be further reduced. Moreover, since there is almost no step difference in the part where the main bevel part 7 and the groove part 6 are in contact, this together with the fact that the cross-sectional shape of the groove part 6 is concavely curved,
When pulling out the inner needle 2, the leading edge of the outer needle that has entered the groove 6 can easily come off from the main bevel 7, so there is no fear that it will get caught in the groove 6 and turn inward. Effects such as being able to pull out smoothly can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a half-sectional view showing an embodiment of the present invention, FIG. 2 is an enlarged view of section A in FIG. 1, and FIG. 3 is an enlarged sectional view of the tip of a conventional indwelling needle. In the figure, 1 is the outer needle, 2 is the inner needle, 4 is the tip of the outer needle, and 6
indicates a groove.

Claims (1)

[Scope of utility model registration request] It consists of a flexible outer needle and a rigid inner needle that is slidably inserted into the outer needle, and has a groove with a concave curved cross section in the circumferential direction at a position in contact with the main bevel at the tip of the inner needle. 1. An indwelling needle characterized in that the outer needle tip has a constricted shape, and the outer needle tip is inserted into the inner needle groove.