JPS6350021B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a body fluid purifier for adsorbing and removing unnecessary or toxic substances from body fluids such as blood or plasma separated from blood.

[Conventional technology]

Recently, much effort has been made to develop body fluid purifiers that adsorb and remove harmful substances from body fluids by bringing adsorbents such as activated carbon and ion exchange resins into direct contact with perfusion fluids such as blood. Among these, those using activated charcoal have been developed for the longest time, and have already been put into practical use for the treatment of drug poisoning and hepatic coma.

Normally, such body fluid purifiers use particulate adsorbent with a particle size of about 1 mm to ensure adsorption area and blood flow, and filters are installed at both ends to prevent adsorbent particles from leaking out. It is used by being filled into a cylindrical container made of synthetic resin.

The blood drawn outside the body adsorbs and removes harmful substances while flowing through channels formed by gaps between particles of the filled adsorbent, and the purified blood is returned to the body for treatment.

[Problem that the invention seeks to solve]

However, adsorbents, including activated carbon, generally have low wear resistance and are prone to generating fine powder.When using adsorbents in body fluid purifiers, how can we prevent the generation of fine powder? An important issue is how to reduce the amount of irrigant mixed into the irrigation fluid. When fine adsorbent powder is liberated, it is transported into the body by the bloodstream and occludes peripheral blood vessels, and if the amount is large, it is deposited in tissues such as the lungs and liver, causing various disorders. Activated charcoal was first studied for the purpose of treating uremia and drug addiction, but the above-mentioned problems were pointed out and it was not widely applied clinically. It came into practical use today when a method was developed to suppress the generation of fine powder by coating activated carbon with a polymer membrane such as nitrocellulose. This is because it has become possible to prevent the deposition of

However, although this method has made it possible to considerably suppress the flow of activated carbon fine powder from the body fluid purifier, it is still necessary to wash it with physiological saline immediately before use.
Even with this cleaning, activated carbon fine powder does not completely disappear, so it is not generally used for the treatment of chronic renal failure, which requires frequent treatment over a long period of time. This is the current situation.

In addition, when this type of body fluid purifier is subjected to the commonly used heat sterilization, the amount of activated carbon fine powder increases compared to before sterilization, and depending on the application, some cleaning may be required before use. I found out something.

As a result of further investigation, the present inventors found that the generation of this activated carbon fine powder is due to the movement of particulate activated carbon due to thermal expansion of the container during heat sterilization, and the activated carbon particles being rubbed against each other. Furthermore, it was discovered that this movement loosens the packed state of activated carbon, making it easier for the activated carbon particles to move during transportation.

Therefore, an object of the present invention is to pressurize a particulate adsorbent such as activated carbon to make it densely packed, wash and sterilize it in advance, remove fine powder of the adsorbent during assembly, and remove the adsorbent after sterilization. Prevents the generation of fine powder,
To provide a method for producing a sterile body fluid purifier that does not require cleaning during use.

[Means for solving problems]

In order to achieve the above object, in the present invention, a particulate adsorbent such as activated carbon is filled in a cylindrical container having an inlet and an outlet at both ends to form an adsorbent layer, A body fluid purifier is constructed by extending filter members with a mesh size smaller than the particle size of the adsorbent on both sides of the adsorbent layer, and the filter members extended on both sides of the adsorbent layer can be adjusted from the outside. The particulate adsorbent is held under pressure so as not to move within the layer, and then the particulate adsorbent is washed to remove fine powder, etc., and then sterilized by gamma ray irradiation. .

[Effect]

In the present invention, when the filter positions in the container are determined, the particulate adsorbent is filled in an amount greater than the volume between the filters, and the filters are pressure-deformed and loaded at the predetermined positions. The layer of particulate adsorbent can be kept in a compressed state by using the elasticity of the adsorbent. Further, it would be very convenient if at least one filter position could be set to a state where the layer of particulate adsorbent is pressed arbitrarily depending on the filling amount of particulate adsorbent. Furthermore, pressure may be applied to the spring filter without fixing the position of the filter.

As the filter, a screen mesh nonwoven fabric, a perforated plate, etc. can be used. In both cases, it is essential that the pores have a diameter that does not allow adsorbent particles to pass through. Appropriate reinforcement is preferably provided to prevent stress relaxation of the filter. It is also essential that the material be resistant to gamma rays.

It is also possible to apply a pressing force by shrinking the length or cross-sectional area of the container after filling.

In order to obtain the full effect of the present invention, it is preferable to make the packed state of the particulate activated carbon as dense as possible before pressing the layer of particulate activated carbon.
For this reason, generally a cylindrical filling container with entrances and exits at both ends is set up almost vertically, one filter is loaded at the bottom of the container, and while the container is appropriately vibrated, particulate activated carbon is poured into the container along with water from above. Preferably, excess water is drained off through a filter at the bottom.

After filling is completed, the upper filter is loaded while pressing the particulate adsorbent layer, a port cap etc. is attached if necessary, and then clean water is preferably irrigated to wash away adsorbent fine powder generated during the filling operation. If the filter pressure has decreased after cleaning, lower the filter position or add particulate adsorbent to restore the filter pressure. The pressing force is preferably as large as possible without destroying the adsorbent particles, and is determined by trial and error. In some cases, it is preferable to increase the packing density of the particulate adsorbent by performing heat treatment during the process. The washing is continued further, and when there is no adsorbent fine powder in the washing water passing through the body fluid purifier, the water in the container is replaced with physiological saline, and the container is subjected to a sterilization process.

In the present invention, the sterilization method is performed by gamma irradiation. Another sterilization method that does not use heat is sterilization using chemicals, but this cannot be used because of the problem of adsorption by adsorbents. Since a slight temperature increase is observed even with gamma ray irradiation, it is preferable to irradiate with gamma rays of as low intensity as possible over a long period of time. The total irradiation dose is determined by the number of bacteria in the body fluid purifier and the safety factor adopted.

〔Effect of the invention〕

According to the method for manufacturing a body fluid purifier according to the present invention, the filter members stretched on both sides of the adsorbent layer are pressurized from the outside in an adjustable manner to prevent particulate adsorbent such as activated carbon from moving within the layer. By holding the particulate adsorbent under pressure, generation of fine adsorbent powder due to thermal expansion during sterilization of the particulate adsorbent and vibration during transportation can be kept to a minimum.

Furthermore, according to the method for manufacturing a body fluid purifier of the present invention,
After the filter member is press-fitted onto the particulate adsorbent layer as described above, clean water is irrigated into the adsorbent layer to wash away adsorbent fine powder generated during the filling operation, and after this washing is completed, the container is removed. Since the water inside the body is replaced with physiological saline and sterilized by gamma ray irradiation, the body fluid purifier obtained by the production method of the present invention needs to be cleaned of the adsorbent fine powder immediately before use. It can be used immediately and is easy to handle.

Although the present invention has mainly been described as an application for blood, it can also be effectively used to remove unnecessary substances from body fluids taken out from the human body, such as plasma separated from blood, and to return the purified body fluids to the human body. can.
Furthermore, although activated carbon or polymer-coated activated carbon has been described as an adsorbent, the present invention is not limited thereto, and is useful for all adsorbents that tend to generate fine powder.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a body fluid purifier according to the present invention will be explained below by way of examples with reference to the accompanying drawings.

In FIGS. 1 and 2, a cylinder 10 is a container body, into which a particulate adsorbent 12 is filled. A port member 14 is slidably fitted into the end of the cylindrical body 10 through an elastic packing 16 (eg, rubber packing) while closely contacting the inner surface of the cylindrical body.
This packing 16 is an O-ring with a circular cross section,
Various types of rings such as U-rings with a U-shaped cross section and trapezoidal cross-sections can be used. cap 18
is screwed in from the outside of the cylindrical body 10, and can be fixed in any position while pressing the port member 14. A screen filter 20 having a mesh size smaller than the particle size of the adsorbent is placed inside the port member, and this filter is attached to the port member 1.
The entire layer of particulate adsorbent 12 is pressed by receiving the pressing force from the cap part via 4. Port member 1
A filter reinforcing porous plate 22 is provided between the screen filter 4 and the filter 20 to prevent the pressing force from being weakened by the screen filter. In the container shown in FIG. 2, in order to widen the range in which the port member can be fixed, the thickness L of the port member and the thread cutting range l in the cap are made as large as possible.

As the adsorbent, beads activated carbon made from petroleum pit was coated with 2 mg of ethyl hydroxyethyl cellulose per gram of activated carbon.

In experiment 1, a lower screen filter was placed on the cylinder.
The perforated plate, port member, elastic packing, and cap were loaded, and the above-mentioned activated carbon was injected together with water from the top of the cylinder. After injecting a small amount, the cylinder was struck from the outside. When the water was about to overflow from the top of the cylinder, the water was drained from the port at the bottom. At this time, care was taken to ensure that the water level did not fall too low because if the water level became lower than the upper surface of the particulate adsorbent layer, air bubbles would be mixed in later. When approximately 300 ml of particulate adsorbent was filled, the upper filter, perforated plate, port member, elastic packing, and cap were loaded and the cap was tightly tightened.

Next, water was flowed through the upper port at a flow rate of 200 ml/min for 5 hours, a port cap (not shown) was fitted to the port, and gamma rays were irradiated at 2.5 megarads.

In Experiment 2, gamma ray sterilization was replaced with heat sterilization at 121°C for 20 minutes. In Experiment 3, after filling, the cap was not tightly tightened and was washed with water at 200 ml/min for 3 hours, followed by irradiation with gamma rays.

The amount of adsorbent fine powder in these three types of body fluid purifiers was evaluated by the method shown in FIG.

Water from the reservoir 30 is sucked by the pump 32, passed through the filter 34 to become clean water, and then forced into the body fluid purifier 36 as a downward flow from above, and the clean water containing the adsorbent powder pushed out from the bottom of the body fluid purifier 36. Water is introduced into a mesh filter 40 fixed in a filter vessel 38 and the adsorbent powder is collected on the filter 40. A vacuum system 42 is used as necessary. The filter 34 and the filter 40 were both capable of trapping powder of about 1 μm or more. The adsorbent powder collected on the filter 40 was counted under a microscope.

In experiment 1, the number of coal particles collected by the filter 40 by flowing water at a flow rate of 200 ml/min for 5 minutes was 27.
The number was 853 in Experiment 2 and 2196 in Experiment 3.

In Experiment 2, the adsorbed particles moved slightly during thermal expansion;
It is presumed that this was caused by friction between the particles. In Experiment 3, the particulate activated carbon was not pressed, so when the irradiation was requested outside the company, the vibration during transportation caused intense friction between the particles or between the particles and the container, resulting in a large amount of fine adsorbent powder. It is estimated to be.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the body fluid purifier used in the example.
FIG. 2 is a longitudinal sectional view of the body fluid purifier shown in FIG. 1, and FIG. 3 is a system diagram of a system for measuring the amount of adsorbent powder flowing out. 10... Cylindrical body, 12... Adsorbent, 14... Port member, 16... Packing, 18... Cap, 20... Filter, 22... Porous plate for reinforcement,
24... Port lumen, 30... Reservoir, 32
... pump, 34 ... filter, 36 ... body fluid purifier, 38 ... filtration container, 40 ... filter, 4
2... Decompression gauge.

Claims (1)

[Claims] 1. A container consisting of a cylinder with an inlet and an outlet at both ends is filled with particulate adsorbent such as activated carbon to form an adsorbent layer, and both sides of the adsorbent layer are filled with a particulate adsorbent such as activated carbon. A body fluid purifier is constructed by extending a filter member with a mesh size smaller than the particle size of the adsorbent layer, and adjustingly presses the filter members provided on both sides of the adsorbent layer from the outside to remove particles. A method for manufacturing a body fluid purifier, characterized in that the adsorbent is held under pressure so that it does not move within the layer, and then the particulate adsorbent is washed to remove fine powder, etc., and then sterilized by gamma ray irradiation. . 2. In the method for manufacturing a body fluid purifier according to claim 1, a container consisting of a cylindrical body with both ends open is filled with particulate adsorbent to form an adsorbent layer,
An inlet-side filter and an outlet-side filter each having a mesh size smaller than the particle size of the adsorbent are installed on both sides of the adsorbent layer, and are pressed against the peripheral edge of each filter by coming into contact with it from the outside. Port members are inserted and arranged in close contact with the inner circumferential surfaces of both ends of the container, and caps that adjustably press and hold these port members from the outside and pressurize the particulate adsorbent via the filter are installed at both ends of the container. A method for manufacturing a body fluid purifier that is attached to a person.