JPH046738Y2 - - Google Patents

Description

[Detailed explanation of the idea]

<Industrial Application Field> The present invention relates to blood collection tubes for blood sediment measurement. More specifically, it combines the functions of a vacuum blood collection tube and a blood sedimentation tube.
The present invention relates to a vacuum blood collection tube for blood sedimentation measurement that can efficiently measure the erythrocyte sedimentation rate. <Prior art> Vacuum blood collection tubes for blood sediment measurement have already been disclosed in U.S. Pat.
No. 73303) Specification and Jitsugansho that improved it
It is disclosed in specification No. 60-136786 and Japanese Utility Model Application No. 74335/1983. As shown in FIG. 3, these conventional vacuum blood collection tubes for blood sediment measurement are composed of a blood collection section 12 and a blood sediment measurement section 11 connected thereto, and are sealed tubes into which a blood collection needle can be inserted, and the inside is pre-vacuumed. A scale 14 for measuring the erythrocyte sedimentation rate is provided on the surface of the transparent or translucent blood sedimentation measuring section 11 or on an outer tube (not shown) into which the sealed tube can be inserted. It is something to do. The vacuum blood collection tube for blood sediment measurement disclosed in Utility Model Application No. 59-158997 requires time to stir and mix the collected blood with the anticoagulant (sodium citrate, etc.) sealed in the tube in advance. Because of this problem, in Utility Application No. 136,786/1986, a partition plate was provided inside the tube in order to improve this and to facilitate stirring and mixing of blood, and in U.S. Patent Application No. 61-74,335
Further improvements have been made in this specification to provide a vacuum blood collection tube for blood sediment measurement that has no variation in stirring speed and no measurement error. <Problems to be solved by the invention> However, conventional vacuum blood collection tubes for blood sediment measurement are
In order to ensure the degree of vacuum inside the blood collection tube, it is also necessary to reduce the penetration resistance when the introduction part of the blood collection needle (a blood collection needle has a cutting edge at both ends, but this refers to the part of the blade that punctures the rubber stopper) into the rubber stopper. In order to prevent the blood sampling part from becoming too large, the diameter of the blood sampling part is larger than that of the blood sediment measuring part. Therefore, (1) an extra process is required to form this large diameter part (hereinafter referred to as the bulge); It is disadvantageous in terms of cost. (2) It is difficult to form the bulge, and accuracy control is difficult due to large variations in dimensions. (3) The swelling part is easy to crack. This was a problem because of the following drawbacks. The present invention was devised in view of the above-mentioned problems, and an object of the present invention is to provide a dimensionally stable and economical vacuum blood collection tube for blood sediment measurement. <Means for solving the problems> As a result of intensive research to solve the above problems, the present inventor has found that the inner diameter of the capillary and the thickness of the rubber stopper can be adjusted without making the blood sampling part large in diameter. The present invention was completed based on the discovery that by appropriately selecting the relationship between the diameter and the outer diameter, the degree of vacuum can be ensured and the penetration resistance of the blood sampling needle can be prevented from becoming excessive. That is, the present invention includes a bottomed capillary made of a transparent gas-impermeable material, a stopper made of a rubber-like elastic material that seals the open end of the capillary, and a stopper inserted into the capillary to seal the inside of the capillary. a partition plate disposed so as to bisect the tube in the longitudinal direction, and an anticoagulant housed in the thin tube, and the inside of the thin tube is reduced to a predetermined pressure. This invention relates to a vacuum blood collection tube for blood sediment measurement. <Operation of the invention> The vacuum blood collection tube for blood sediment measurement of the present invention has a reduced pressure inside, so when collecting blood, the puncture part of the blood collection needle (the side that is inserted into the human body) is inserted into the vein, and the introduction part is closed with a rubber stopper. When the vein is inserted into the blood collection tube to establish communication between the vein and the inside of the blood collection tube, blood is automatically collected into the blood collection tube due to the relative negative pressure inside the blood collection tube. In addition, a partition plate is placed inside the blood collection tube so as to divide the inside of the tube into two along the longitudinal direction.
In order to mix the collected blood and anticoagulant, the blood collection tube is alternately reversed to stir the blood, but at this time the balance of surface tension acting on the blood surface tends to be lost. Therefore, blood flow becomes easier, so
The time required to stir the blood is significantly reduced. <Example> Next, an example of the present invention will be described based on the drawings. Fig. 1 is a partially cutaway front view showing an embodiment of the vacuum blood collection tube for blood sediment measurement of the present invention, and Fig. 2 is an exploded view of the components in Fig. 1 (however, the anticoagulant is stored in the capillary). ), FIG. 3 is a partially cutaway front view showing a conventional vacuum blood collection tube for blood sediment measurement. As shown in FIGS. 1 and 2, the vacuum blood collection tube 1 for blood sediment measurement of the present invention includes a capillary tube 2 with a bottom and a rubber-like elastic material, preferably butyl rubber, sealed at the open end of the capillary tube 2. a rubber stopper 3, a partition plate 4 inserted into the thin tube 2 and arranged so as to divide the internal space into two along the longitudinal direction, and the thin tube 2.
The inside of the thin tube 2 is evacuated to a predetermined pressure of around 105 mmHg. The thin tube 2 is generally made of a transparent gas-impermeable material such as glass, and although not shown, the blood sedimentation rate measurement portion of the thin tube 2 or the thin tube 2
A separate transparent tube thin tube 2 into which can be inserted
A scale is provided at the part corresponding to the blood sedimentation rate measurement site. The length of the thin tube 2 is based on the fact that the length of the scale part of the blood sedimentation tube 1 is determined to be 200 mm according to the international standard method of the Westergren method.
Considering the length of the rubber plug 3, it is formed to be 210 mm or more, preferably 220 to 240 mm. In addition, the inner diameter of the thin tube 2 is 3 to 5 mm, preferably 4.0 to 5 mm, in order to reduce the amount of blood collected and to prevent difficulty in plugging with the rubber stopper 3.
It is formed to 4.5mm. The rubber stopper 3 is generally made of butyl rubber, which has excellent gas barrier properties, and is formed into a conventional shape, for example, as shown in FIG. 2. The sealing surface where the rubber stopper 3 and the thin tube 2 come into contact is formed to have a width of at least 3 mm or more in the longitudinal direction of the thin tube 2 in order to maintain a predetermined degree of vacuum. The thickness of the rubber stopper 3 is 3 to 7 mm, preferably 3.5 to 5.0 mm, in order to maintain the degree of vacuum and prevent excessive penetration resistance of the blood collection needle. The ratio of the maximum outer diameter of the contact surface between the rubber stopper and the capillary (herein referred to as the maximum outer diameter of the contact surface between the rubber stopper and the capillary) and the inner diameter of the capillary 2 (outer diameter of the rubber stopper/inner diameter of the capillary, hereinafter referred to as compression ratio) is 1.05 to 1.18, preferably 1.07 to Formed in 1.15. If the compression ratio is less than 1.05, there will be a problem in maintaining the degree of vacuum, and if the compression ratio exceeds 1.18, it will be difficult to plug the rubber stopper 3 and the penetration resistance of the blood collection needle will become excessive. The partition plate 4 is for making it easier to stir the collected blood, and is formed to a length that creates a small space between the rubber stopper 3 and the open end of the thin tube 2. The width of the partition plate 4 is preferably slightly smaller than the inner diameter of the thin tube 2. This is done by bringing the ends of the partition plate 4 in the width direction and the inner wall of the thin tube 2 into close contact, so that there is no gap between the ends of the partition plate 4 in the width direction and the thin tube 2, and on both sides of the partition plate. This is to maximize blood flow by preventing leaks. As shown in FIG. 2, the shape of the partition plate 4 is such that the lower tip portion is partially cut out, and the upper portion including the portion corresponding to the blood surface is narrow. The functions of these notch portions 6 and narrow portions 7 have already been explained in the Utility Model Application No. 61-
Since it is described in detail in the specification of No. 74335, it will be omitted. Unlike the preferred partition plate in the specification of Utility Model Application No. 61-74335, the partition plate 4 in the present invention is
The reason why the width is narrow up to the upper tip is because if the width of the partition plate 4 and the thin tube 2 is too small, blood will remain in the form of a film between the partition plate 4 and the thin tube 2. In this case, it has been confirmed that blood adhesion as shown in the experimental example of Utility Model Application No. 1983-74335 does not occur; Even if the upper end portion of the partition plate 4 is made narrow, the distance between the narrow part 7 of the partition plate 4 and the inner wall of the thin tube 2 is small, approximately 2.3 mm at most, so that the attached blood will be absorbed into the narrow part 7. This is because blood is likely to come into contact with the narrow portion 7, and therefore blood is likely to fall along the narrow portion 7. The partition plate 4 is made of a transparent material for easy viewing during blood sedimentation measurement, and its thickness is 0.2 mm or more.
Preferably it is 0.5 to 1.0 mm. Sodium citrate is generally used as the anticoagulant 5,
Generally, blood is stored in the tubule 2 in advance at a ratio of 0.5 ml to 2.0 ml of blood. <Test Example 1> Using a glass tube with an inner diameter of 4.3 mm, the stirring speed of bovine blood and the state of bubble generation were observed by changing the length, and the results shown in Table 1 were obtained. It can be seen from the table that the length of the glass tube is preferably 220 to 240 mm.

[Table] <Test Example 2> The inside of a glass tube with an inner diameter of 4.3 mm and a length of 230 mm was
Using a vacuum blood collection tube for blood sediment measurement that was depressurized to mmHg and plugged with a rubber stopper with a wall thickness of 3.7 mm and an outer diameter of 4.7 mm, the amount of inhaled blood and the height of the blood surface were measured.
The results shown in the table were obtained. Approximately 0.5ml of sodium citrate is stored in the tube. It can be seen from the table that the amount of blood collected and the height of the blood surface after blood collection are almost constant.

[Table] <Test Example 3> We measured the penetration resistance when a blood sampling needle was inserted into a glass tube with an inner diameter of 4.3 mm by changing the outer diameter of the rubber stopper, and the results are shown in Table 3. was gotten. The thickness of the rubber stopper was 3.7 mm, and the size of the blood collection needle was 20G (outer diameter 0.9 mm). It can be seen from the table that the compression ratio is preferably in the range of 1.07 to 1.15.

[Table] <Effects> As is clear from the above explanation, the vacuum blood collection tube for blood sediment measurement of the present invention has the following advantages compared to those having a swelling part. (1) It is economical because it does not require the formation of a swelling. Furthermore, the disadvantage of being easily broken is eliminated. (2) There is little variation in dimensions and accuracy control is easy. (3) Since there is no swelling part, packaging materials and storage space can be saved.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view showing an embodiment of the present invention, Fig. 2 is an exploded view of the components in Fig. 1, and Fig. 3 is a diagram showing a conventional vacuum blood collection tube for blood sediment measurement. FIG. Explanation of main symbols, 1... Vacuum blood collection tube for blood sediment measurement, 2... Thin tube, 3... Rubber stopper, 4... Partition plate,
5... Anticoagulant.

Claims (1)

[Claims for Utility Model Registration] 1. A thin tube with a bottom made of a transparent gas-impermeable material, a stopper made of a rubber-like elastic material that seals the open end of the thin tube, and a plug inserted into the thin tube. It consists of a partition plate arranged to divide the inside of the thin tube into two along the longitudinal direction, and an anticoagulant housed in the thin tube, and the inside of the thin tube is reduced to a predetermined pressure. In the blood collection tube, the capillary has a uniform inner diameter without a swelling part, and the capillary has an inner diameter of 4.0 to 4.5 mm and a length.
220 to 240 mm, the rubber stopper has a thickness of 3.5 to 5.0 mm, and a compression ratio of 1.07 to 1.15 when the rubber stopper is inserted into a thin tube. 2. The blood collection tube according to claim 1, wherein the rubber-like elastic body is butyl rubber. 3. The blood collection tube according to claim 1, wherein the width of the partition plate is slightly smaller than the inner diameter of the thin tube.