JPH0231990B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL FIELD OF APPLICATION The present invention relates to a connecting tube in an infusion administration circuit. Prior Art and its Problems Connecting tubes for infusion administration circuits, typified by infusion sets, are required to be flexible, so those made of soft vinyl chloride resin are mainly used. However, vinyl chloride resin adsorbs fat-soluble drug components such as nitroglycerin, isosorbite nitrate, and diazepam, which poses a problem during actual administration. For nitroglycerin, polyethylene, polypropylene, acrylonitrile-butadiene resin, polyester, polyamide,
Fluorine resins and the like are known as non-adsorptive resins, but since these resins are all hard materials and lack flexibility, they cannot be used alone as a connecting tube for infusion. For this reason, the inner layer is low-density polyethylene (LDPE), which does not adsorb nitroglycerin, and the outer layer is ethylene-vinyl acetate copolymer (EVA), which adsorbs nitroglycerin but is flexible and has good adhesion to LDPE. Layered tubes have been put into practical use as connecting tubes for nitroglycerin infusion sets. However, in this two-layer tube, in order to maintain the strength of the inner layer and improve pinhole resistance,
The thickness of the LDPE must be above a certain level, and in order to improve the adhesion between the outer layer and the inner layer, the outer layer EVA
Since it is also necessary to increase the blending ratio of ethylene in the tube, the flexibility of the tube cannot be said to be satisfactory as a result. Therefore, when connecting such a double-layered tube infusion set to an infusion pump, the tube is not sufficiently occluded by the pressure of the infusion pump finger, and the rate of infusion administration cannot be controlled. do not have. For this reason, it is necessary to use a flexible silicone tube as part of the connecting tube or to connect a volumetric type pump cassette, which inevitably increases costs and complicates the work. Means for Solving the Problems As a result of extensive research in view of the current state of the technology as described above, the present inventor has developed a combination of linear low-density polyethylene (hereinafter referred to as LLDPE) and thermoplastic polystyrene-based elastomer (hereinafter referred to as polystyrene-based elastomer). A blended resin containing a specific proportion of a thermoplastic polyolefin elastomer (hereinafter referred to as an elastomer) or a thermoplastic polyolefin elastomer (hereinafter referred to as a polyolefin elastomer) does not substantially adsorb drug components in an infusion, and has softness, flexibility, strength, It was also found that it has excellent pinhole resistance. That is, the present invention provides (a)
LLDPE and (b) polystyrene elastomer and/or
Alternatively, it relates to a connecting tube for infusion without drug adsorption, which is made of a blend resin with a polyolefin elastomer and has a blending ratio of component (b) of 5 to 40% by weight. The linear low-density polyethylene used in the present invention is a copolymer of ethylene-α-olefin, and structurally has a linear polyethylene chain and short side chains of α-olefin, and has a density of 0.92 to 0.94 g/cm. It is a linear polyethylene of grade ³ (according to ASTM 1505). α-olefins include butene-1, hexene-1, methylpentene-1, octene-1
etc. are exemplified. Particularly preferred, the density
An example is 0.92 g/cm ³ of ethylene-butene-1 copolymerized linear low density polyethylene. In addition, thermoplastic polystyrene elastomer is
It is a block copolymer of styrene and butadiene, isoprene, ethylbutylene, etc., and has a molecular weight of
It is a polystyrene-based elastomer with a styrene content of about 30,000 to 60,000 and a styrene content of 50% or less. Examples of polystyrene elastomers include styrene-butadiene-styrene elastomer, styrene-ethylbutylene-styrene elastomer, and styrene-butadiene-styrene elastomer.
Examples include ethylene-butadiene-styrene elastomer and styrene-isoprene-styrene elastomer. A particularly preferred example is a styrene-ethylbutylene-styrene elastomer having a density of 0.90 g/cm ³ . The thermoplastic polyolefin elastomer is an ethylene-propylene amorphous random copolymer. Specifically, they are ethylene-propylene-methylene linkage (EPM) and ethylene-propylene-dienemethylene linkage (EPDM), and in the case of EPDM, 5-
Examples include those obtained by polymerizing ethylidene 2-norbornene (ENB), dicyclopentadiene (DCP), or 1,4-hexadiene (1,4HD).
In the case of EPM, the density is about 0.85 to 0.87 g/ ^cm3 ,
In the case of EPDM, the density is approximately 0.87 to 0.90 g/cm ³ . More preferably, ENB with a density of 0.88 g/cm ³
Examples include EPDM polyolefin elastomers. In the present invention, the blending ratio of (a) LLDPE and (b) polystyrene elastomer and/or polyolefin elastomer is usually 60 to 95 parts by weight of component (a) and 40 to 40 parts by weight of component (b) in 100 parts by weight of blend resin. It is about 5 parts by weight, and more preferably about 30 to 20 parts by weight of component (b) to 70 to 80 parts by weight of component (a). If the blending ratio of component (b) is less than 5% of the weight of the blended resin, the flexibility of the connecting tube will not be sufficient and the finger portion will not be able to be pressed when attached to a peristaltic finger infusion pump. Due to this, the tube is not completely occluded, and the tube is not easily restored when the pump is driven. On the other hand, when the blending ratio of component (b) exceeds 40% of the weight of the blend resin, adsorption of nitroglycerin becomes significant. The infusion connection tube of the present invention can be used as is in place of an existing connection tube in a known infusion administration circuit. Effects of the Invention According to the present invention, the following remarkable effects are achieved. (i) Does not substantially adsorb fat-soluble drug components in infusions. (ii) Because of its excellent flexibility, the tube can be easily occluded by pressure from the infusion pump finger;
Thus, the rate of infusion administration can be accurately controlled. (iii) Excellent flexibility, strength, pinhole resistance, etc. Examples Examples will be shown below to further clarify the features of the present invention. Example 1 As a connecting tube for the infusion set shown in Figure 1
Tubes were made from blended resins containing LLDPE (abbreviated as L) and polystyrene elastomer (abbreviated as E) in various proportions shown in Table 1.
As the LLDPE, ethylene-butene-1 copolymer (density 0.92 g/cm ³ ) was used, and as the polystyrene elastomer, styrene-ethylbutylene-styrene elastomer (density 0.90 g/cm ³ ) was used. In the infusion set shown in Fig. 1, 1 is a drug introduction needle, 2 is an upper tube, 3 is an upper clamp, and 4 is an upper tube.
5 indicates a metering tube, 5 indicates a drip tube, 6 indicates a lower clamp, 7 indicates a lower tube, and 8 indicates a Lure tip. The tubes having the composition shown in Table 1 were used as the upper tube 2 and the lower tube 7. The nitroglycerin injection solution was diluted with physiological saline to a concentration of 100 μg/ml to prepare a test solution, and 100 ml of the test solution was injected into the metering cylinder 4. Then,
After venting the air in the circuit of the infusion set, attach it to the infusion pump (model 530 manufactured by IVAC, USA).
The test solution was continuously added dropwise at a flow rate of 10 ml/hr. Table 1 also shows the results of examining the adsorption properties of nitroglycerin and compatibility with infusion pumps. In addition, the adsorption of nitroglycerin was determined by sampling the effluent from Lure arch tip 8 over time and quantifying it using high performance liquid chromatography as follows. Adsorption was determined when the following conditions were met. Equipment: Model 638 column manufactured by Hitachi, Ltd.: ERC-ODS1161 manufactured by ERMA OPTICAL WORKS, USA Mobile phase: Acetonitrile: Tetrahydrofuran:
Water = 260:100:640 Flow rate: 2.0ml/min Detector: UV Detector (218nm) Also, regarding compatibility with infusion pumps, (a) the tube is completely occluded by pressing the tube with the infusion pump finger and It is possible to control the discharge of liquid at a predetermined flow rate, and (b) 500 ml of superpure water is discharged through a tube using an infusion pump.
(Through a 0.45μm membrane filter)
was further passed through a 0.45 μm membrane filter, and then placed on the filter under a 100x microscope.
The case where no resin foreign matter of 0 μm or more was observed was considered suitable.

[Table] Example 2 Example 1 except that a blended resin containing LLDPE (abbreviated as L) and polyolefin elastomer (abbreviated as OE) in the proportions shown in Table 2 was used.
After obtaining a connecting tube in the same manner as in Example 1, the degree of nitroglycerin adsorption and compatibility with the infusion pump were examined in the same manner as in Example 1. The results are shown in Table 2. As the polyolefin elastomer, ENB EPDM having a density of 0.88 g/cm ³ was used.

[Table] Example 3 LLDPE similar to Example 1 in the proportions shown in Table 3.
(abbreviated as L), the same polystyrene elastomer as in Example 1 (abbreviated as E), and the same polyolefin elastomer as in Example 2 (abbreviated as OE) were used.
A connected tube was obtained in the same manner as above. Table 3 shows the results of examining the degree of nitroglycerin adsorption and compatibility with infusion pumps in the same manner as in Example 1.

【table】

[Table] Example 4 75% by weight of LLDPE similar to Example 1 and 25% by weight of polystyrene elastomer similar to Example 1
A tube was prepared from a blend resin consisting of the following, and the adsorption of nitroglycerin was measured in the same manner as in Example 1 using this tube. Curve A in FIG. 2 shows the results of sampling the effluent over time from the start of the infusion pump drive. It is clear that almost no adsorption of nitroglycerin is observed. Example 5 LLDPE 75% by weight as in Example 1 and Example 2
25% by weight of polyolefin elastomer similar to
Create a tube from a blended resin consisting of
Using this as a connecting tube, the adsorption of nitroglycerin was measured in the same manner as in Example 1. As shown by curve C in FIG. 3, it is clear that almost no adsorption of nitroglycerin was observed. Example 6 LLDPE 75% by weight as in Example 1, Example 1
A tube was prepared from a blended resin consisting of 15% by weight of the same polystyrene elastomer as in Example 2 and 10% by weight of the same polyolefin elastomer as in Example 2, and the tube was used to measure the adsorption of nitroglycerin in the same manner as in Example 1. did. The results of sampling the effluent over time from the start of driving the infusion pump are shown as curve D in FIG. It is clear that almost no adsorption of nitroglycerin is observed. Comparative Example 1 Nitroglycerin adsorption was measured in the same manner as in Example 1 for a commercially available infusion set using a flexible vinyl chloride resin connection tube. The results are shown as curve B in FIGS. 2 to 4. It is clear that the adsorption of nitroglycerin is significantly greater.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of an infusion set using the connecting tube of the present invention, and FIGS. 2 to 4 are
It is a graph showing the degree of adsorption of nitroglycerin in Examples and Comparative Examples of the present application. 1...Medical solution introduction needle, 2...Upper tube, 3...
...Upper clamp, 4...Metering tube, 5...Drip tube,
6...Lower clamp, 7...Lower tube, 8...
...Lurearchtip.

Claims (1)

[Claims] 1 Consists of a blended resin of (a) linear low-density polyethylene and (b) thermoplastic polystyrene elastomer and/or thermoplastic polyolefin elastomer, and the blending ratio of component (b) is 5 to 40% by weight. A connecting tube for infusion without drug adsorption, characterized by: