JP4806890B2 - Medical molded parts - Google Patents

Description

  The present invention relates to a medical molded member and an infusion device used in the medical field such as infusion and blood transfusion.

Conventionally, a thermoplastic polymer such as polyvinyl chloride (PVC) has been used as a material of a molded member forming a medical device. In particular, PVC is light in weight and difficult to break. Therefore, in medical fields such as infusion and blood transfusion, PVC is frequently used as a material for molding disposable medical molded members such as infusion tubes, bags, and connectors that constitute infusion sets.
On the other hand, as disclosed in Patent Document 1 and Patent Document 2, rubber-like materials using 1,2-polybutadiene, soft polyolefin elastomer, and the like have been proposed as materials for infusion tubes and bags.
Japanese Patent Laid-Open No. 2-305834 JP-A-5-192390

  In such a medical device, the gas dissolved in the infusion solution or blood may become bubbles and adhere to the wall surface of the medical molded member, which may become large bubbles. In particular, in the medical molded member using the above 1,2-polybutadiene or soft polyolefin elastomer, the wettability with respect to the liquid is not good, so that bubbles easily adhere to the wall surface. That is, once a bubble adheres to the wall surface, it is difficult to separate from the wall surface, so that it is likely to grow into a large bubble.

  The generation of a large bubble size in the medical molded member is not preferable in consideration of the possibility that the bubble flows into the body. When infusion is performed using an infusion pump, when an air bubble having a predetermined length (5 mm) is detected in the infusion line, the infusion pump is used to prevent the air bubble from being fed into the body at once. Action is taken to urgently stop feeding. If the bubbles easily adhere to the tube wall surface, the bubbles easily grow. As a result, the pump is frequently stopped. In order to avoid such a situation as much as possible, the treatment person is forced to perform a complicated procedure of frequently vibrating the tube to release the bubbles when bubbles start to adhere. Another problem is that when bubbles are attached, the bubbles are obstructed and liquid feeding by the pump is not stable.

  In view of the above-mentioned problems, the present invention aims to prevent large bubbles from forming in an infusion or blood in a medical molded member, and in particular, to prevent bubbles from adhering to the inner wall of the medical molded member. To do.

In order to solve the above problems, the medical molded member according to the present invention uses a material in which 0.02 part by weight or more and 5 parts by weight or less of fatty acid amide is added to 100 parts by weight of the thermoplastic polymer. did.
The “fatty acid amide” referred to here also includes fatty acid amide derivatives.
Examples of the thermoplastic polymer include polybutadiene, styrene-butadiene-styrene copolymer (SBS), styrene-isoprene-styrene copolymer (SIS), and styrene-ethylene-butylene-styrene copolymer (SEBS: hydrogen SBS). A vinyl aromatic elastomer such as a styrene-ethylene-propylene-styrene copolymer (SEPS: hydrogenated SBS) or an olefin elastomer such as an ethylene-propylene copolymer.

The fatty acid amide to be added preferably has a hydrophilic functional group such as a hydroxyl group, a carboxyl group, or an ether group.
Preferred fatty acid amides include polyoxyethylene alkylamine-aliphatic amides , N -methylol stearic acid amides, and polyoxyethylene oleic acid amides .

According to the present invention, the fatty acid amide is added to the material for the medical molded member in an amount of 0.02 to 5 parts by weight based on 100 parts by weight of the thermoplastic polymer. The amide improves the wettability of the thermoplastic polymer to the infusion. Therefore, since it becomes difficult for bubbles to adhere to the wall surface, the bubbles are detached from the wall surface before they grow large.
In order to obtain such an effect, only the fatty acid amide has to be added to the thermoplastic polymer. That is, it is possible to suppress the formation of large bubbles in the medical molded member without using other additives.

If a vinyl aromatic elastomer such as polybutadiene, SEBS, or SEPS or an olefin elastomer such as an ethylene-propylene copolymer is used as the thermoplastic polymer, flexibility can be obtained without adding a plasticizer. It is suitable as a material for infusion tubes, infusion bags and blood bags that require flexibility.
Fatty acid amide to be added has a hydrophilic functional group such as hydroxyl group, carboxyl group, ether group, for example, polyoxyethylene alkylamine-aliphatic amide , N -methylol stearic acid amide, polyoxyethylene oleic acid amide If is used, the effect of increasing the wettability of the wall surface is great, so the effect of making it difficult for bubbles to adhere to the wall surface is also great.

Furthermore, the addition of these fatty acid amides can also be expected to have an inhibitory effect on self-adhesive properties unique to elastomers.
Such a medical molded member is suitable for forming an infusion channel in an infusion device.

Hereinafter, an infusion set according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing a main configuration of the infusion set.
This infusion set is composed of an infusion bag 1, a drip tube 2, an infusion pump 3, an infusion tube 4, 5, an insertion portion 6 and the like containing a chemical solution. To be supplied to patients.

The infusion tube 2 is located below the infusion bag 1, the infusion pump 3 is located below the infusion tube 2, the infusion tube 4 is connected between the infusion bag 1 and the infusion tube 2, and the infusion tube 5 is an infusion tube. 2 to the insertion part 6 via the infusion pump 3. The insertion unit 6 is connected to a patient's vein or the like.
The liquid feeding mechanism of the infusion pump 3 is not limited to any one, but may be a roller type, for example. In the case of the roller type, the infusion tube 5 is fixed to the roller portion, and the infusion tube 5 is squeezed from the outside with the roller portion to push out the infusion in the infusion tube 5.

The infusion tubes 4 and 5 are formed of a material in which a fatty acid amide antifogging agent is added in an amount of 0.02 parts by weight to 5 parts by weight with respect to 100 parts by weight of the thermoplastic elastomer as a base material.
(Effect by using infusion tubes 4 and 5)
In general, when large bubbles are generated in the liquid in the infusion tube, the bubbles may enter the patient's body, which is not preferable. Here, some infusion pumps 3 have a function of stopping the driving of the infusion pump when the presence of large bubbles is detected. In this case as well, the supply of infusion is performed while the pump is stopped. Is not preferable because it stops.

On the other hand, in the infusion tubes 4 and 5, the added fatty acid amide improves the wettability of the thermoplastic elastomer as a base material to the infusion solution, so that bubbles are less likely to adhere to the inner wall surfaces of the infusion tubes 4 and 5. Become. Therefore, since bubbles are detached from the wall surface before they grow large, large bubbles are not generated.
The base material of the infusion tubes 4 and 5 may be a thermoplastic elastomer, and the type thereof is not limited, but it is preferable not to contain a nonpolar plasticizer in order to suppress infusion of the infusion solution.

Preferable base materials include vinyl aromatic elastomers such as polybutadiene, SBS, SIS, SEBS, and SEPS, and olefin elastomers such as ethylene-propylene copolymer.
Generally, infusion tubes are basically required to have flexibility or elasticity, but infusion tubes based on PVC have DEHP (di-2-ethyl-hexyl phthalate) to provide flexibility. ) Is added in a large amount, there is a possibility that the DEHP is eluted in the infusion solution. Moreover, when using a fat-soluble chemical | medical agent (for example, sandumin) as an infusion solution, an infusion solution may adsorb | suck to DEHP.

  On the other hand, vinyl aromatic elastomers such as the above polybutadiene, SBS, SIS, SEBS, and SEPS, or olefin elastomers such as ethylene-propylene copolymer, the base material itself has elasticity, Elasticity can be obtained without adding a plasticizer such as DEHP. Therefore, the elasticity of the tube can be obtained without the plasticizer being eluted into the infusion solution. In addition, the addition of fatty acid amides to the infusion tubes 4 and 5 also has an anti-blocking effect, so that sufficient anti-blocking properties can be ensured without adding other additives (anti-blocking agents). It is expected to be possible.

  Furthermore, when PVC is used as the base material of the infusion tube, hydrogen chloride is generated during incineration, but this hydrogen chloride causes damage to the incinerator and causes dioxin generation. On the other hand, if a vinyl aromatic elastomer such as polybutadiene, SBS, SIS, SEBS, or SEPS, or an olefin elastomer such as ethylene-propylene copolymer is used as a base material, hydrogen chloride is incinerated during tube incineration. Does not occur.

As fatty acid amides to be added to the substrate, those having hydrophilic functional groups such as hydroxyl groups, carboxyl groups, and ether groups have a great effect of improving the wettability of the substrate wall surface with respect to the liquid. The effect of making it difficult to adhere is also considered to be great.
As the fatty acid amide, polyoxyethylene alkylamine-aliphatic amide , N -methylol stearic acid amide, and polyoxyethylene oleic acid amide are preferable.

(Application to medical molded parts other than infusion tubes)
Moreover, what was demonstrated as a material of the infusion tube 4 and 5 above is not restricted to an infusion tube, but generally a medical molded member that requires flexibility, for example, the material of the infusion bag 1, the material of the blood bag, and the like It is also suitable for a medical molded member that is in contact with an infusion solution and blood and in which the adhesion of bubbles is considered a problem.

  That is, in an infusion bag, a blood bag, or the like, by using a material containing a thermoplastic elastomer as a base material and adding 0.02 to 5 parts by weight of a fatty acid amide to 100 parts by weight of the base material, Since the wettability to blood is improved, large bubbles are hardly generated on the wall surface. Therefore, a large bubble does not flow into the body from the insertion part 6, and the flow in the bag or the infusion tubes 4 and 5 is not hindered by the bubble.

Further, since flexibility and elasticity can be obtained without adding a plasticizer to the base material, the elasticity of the bag can be obtained without the plasticizer being eluted into the infusion solution.
In the above description, a medical molded member based on a thermoplastic elastomer has been described. In general, in a medical molded member based on a thermoplastic polymer, a fatty acid amide is similarly added to the base material. Since the wettability with respect to the liquid can be improved, the generation of large bubbles can be suppressed. For example, even when molding a connector for connecting an infusion tube using PVC as a base material, by adding a fatty acid amide to the base material, it is possible to improve the wettability to the liquid and suppress the generation of large bubbles. it can.
(Example 1)

By extruding, using an extruder, a material obtained by adding 0.3 part by weight of trinone O7E (manufactured by Nippon Kasei), which is a fatty acid amide derivative, to 100 parts by weight of 1,2-polybutadiene RB810 (manufactured by JSR) Then, an infusion tube according to the example was produced.
Moreover, the infusion tube concerning a comparative example was produced by extrusion-molding only 1, 2- polybutadiene RB810 using an extruder.

In all cases, the inner diameter of the tube was 3.1 mm, and the outer diameter was 4.5 mm.
(Experiment 1)
Each tube of the produced Example and Comparative Example was filled with physiological saline, and 10 μL of air was injected into the solution using a microsyringe, and the appearance of bubbles adhering to the inner surface of the tube was observed.

As a result, in the tube of the comparative example, the area where the bubbles 22 in the physiological saline solution 20 contacted the tube wall surface was large as shown in FIG. 2B, but in the tube of the example, as shown in FIG. The bubbles 21 in the physiological saline 20 were present in a round state, and the area in contact with the tube wall surface was small.
This result shows that in the tube of the example, the wettability with respect to the physiological saline was improved by adding the fatty acid amide derivative to 1,2-polybutadiene as compared with the tube of the comparative example.

(Experiment 2)
After sterilizing each tube of the produced Example and Comparative Example with ethylene oxide gas, a bag containing physiological saline previously cooled to 4 ° C. and a drip tube were connected, and an infusion pump was attached to the tube. The set was assembled. The infusion pump is provided with a bubble sensor for detecting bubbles in the tube, and the pump is stopped when a large bubble having a length of 5 mm or more is detected in the tube.

Then, in the assembled infusion set, the state where bubbles adhered to the inner surface of the tube was observed while the infusion pump was driven to infuse at 80 mL / h.
As a result, in the infusion set using the tube of the comparative example, the bubble sensor detected a large bubble 2 hours after the start of the infusion, and the infusion pump stopped, whereas in the infusion set using the tube of the example, the infusion set was large. The infusion could be continued without generating bubbles.

(Experiment 3)
As in Experiment 2 above, the inside of the infusion set was primed with a physiological saline solution that had been cooled to 4 ° C. in advance, and the bottom of the infusion set was closed to leave the physiological saline in the infusion set. did.
After leaving for 24 hours, the removability of bubbles adhering in the tube was examined.

  As a result, in the infusion set using the tube of the comparative example, it was difficult to move the bubbles even if they were violently hit from the outside of the tube with a kocher etc. In the infusion set using the example tube, although air bubbles adhered to the inside of the tube, the air bubbles rose to the drip tube by lightly tapping the outside of the tube with a finger, and the air bubbles were easily removed.

  The present invention can be applied to the medical field such as infusion and blood transfusion, and is particularly suitable for disposable medical molded members such as infusion tubes, bags, and connectors constituting an infusion set.

It is a figure which shows the structure of the infusion set which concerns on one Embodiment invention of this invention. In the tube of an Example and a comparative example, it is a figure which shows a mode that a bubble contacts a tube wall surface.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Infusion bag 2 Infusion tube 3 Infusion pump 4 Infusion tube 5 Infusion tube

Claims (2)

A medical molded member that forms a channel for infusion or blood,
For 100 parts by weight of a thermoplastic polymer made of polybutadiene,
Medical molding comprising a material to which a fatty acid amide selected from polyoxyethylene alkylamine-aliphatic amide , N -methylol stearic acid amide, and polyoxyethylene oleic acid amide is added in an amount of 0.02 to 5 parts by weight Element. An infusion set having a flow path for circulating the infusion,
At least a portion of the flow path is
An infusion set comprising the medical molded member according to claim 1.

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