JPH08289930A - Liquid circuit deaerating plug - Google Patents

Abstract

PURPOSE: To remove simply, safely and surely air in a blood circuit in a hollow fiber membrane structure receiving a hydrophobic perforated hollow fiber membrane in a vessel by setting an average bore of the hydrophobic hollow fiber membrane within a specified range. CONSTITUTION: A deaerating plug for a blood circuit and a deaerating plug in a catheter consist of hydrophobic perforated hollow fiber membrane bundles 1 having an opening part 4 in the tip sealed so that the tip end of the hollow fiber membrane is sealingly connected to a vessel by adhesives in the liquid tight manner when the fiber membrane bundle is inserted in the opening part of the vessel. The fiber membrane bundle having the average bore within 0.5-0.8μm of the range is used for a hollow fiber membrane structure. Also, the plug is provided in the end with a check valve 2. When the deaerating plug is thus composed of the perforated hollow fiber membrane, the rate of the membrane area to the volume can be designed to be small, so that the deaerating plug itself can be lessened while a priming amount of blood and drug liquid can be reduced relatively to the deaerating speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood circuit degassing plug and a catheter degassing plug. In the blood circuit in the extracorporeal circulation of blood, it is essential to remove the air in the circuit. The present invention makes it possible to remove air in a blood circuit simply, safely and reliably.

[0002]

2. Description of the Related Art In open heart surgery, extracorporeal circulation is performed by a cardiopulmonary device for guiding blood to the outside of the body in order to substitute the functions of the heart and lungs. Also, in blood purification therapies such as dialysis, plasma exchange, blood filtration, and blood adsorption, blood is guided outside the body to be treated by extracorporeal circulation by a blood purification device.

In the extracorporeal circulation of blood, prior to the circulation, the blood circuit is filled with a priming liquid such as physiological saline or blood. At that time, it is necessary to replace the air existing in the circuit part of the blood with the priming liquid or the blood. To do this, introduce the priming liquid or blood into the circuit from one end of the circuit, and from the other end or vent (air vent) The air is expelled to prevent the priming liquid or blood from being washed away with forceps or a cock just before the priming liquid or blood overflows. For this reason, it was necessary to constantly monitor these operations.

As a conventional technique, a hydrophobic porous polymer molded body (molded body of polymer particles) is used for degassing a blood circuit by allowing air to pass but not water or blood. It is known. This surely allows air to pass, and prevents the priming liquid and blood from passing when the pressure of the priming liquid and blood is as low as about 40 mmHg, but at higher pressures, the priming liquid and blood leak. Since blood pressure is usually higher than this pressure, there is a high risk that blood will leak to the vent plug of the blood circuit or leak to the pores on the surface of the plug. The risk of intrusion cannot be ignored. The average diameter of this vent plug is 2
It is 0 to 30 μm, and it is considered that invasion of bacteria from this degassing plug cannot be avoided.

The catheter is a general term for tubing to be inserted into a blood vessel. Generally, a contrast agent for injecting a drug solution into the body or taking out information from the body, or a predetermined temperature for measuring a local blood flow is used. It is used to obtain physiological saline by flowing it into a blood vessel at a predetermined position and knowing the temperature change. Regardless of the purpose of using a catheter, when injecting a liquid into the body, it is essential to prevent air (air bubbles) from entering the blood vessel. Conventionally, a three-way stopcock, etc. was installed between the catheter and the liquid injection circuit, and air (air bubbles) was used with great care.
Had been removed.

[0006]

DISCLOSURE OF THE INVENTION The present invention uses air in a blood circuit by using a hydrophobic porous hollow fiber membrane or a hydrophobic porous flat membrane having a specific average pore size different from the conventional degassing method. The purpose of the present invention is to provide a liquid circuit degassing plug capable of easily, safely and surely removing the above.

[0007]

The present inventors have overcome the shortcomings of the prior art and have, when removing air from the blood circuit, an average pore size of any of the ranges of 0.05 to 0.8 .mu.m. By providing a liquid circuit degassing plug consisting of a hydrophobic hollow fiber membrane (hereinafter referred to as degassing plug), air is allowed to pass through, but priming liquid and blood do not pass under the hydraulic pressure when operating the circuit. By completely shutting off, and further by providing the degassing plug of the present invention between the catheter and the drug solution injecting circuit, the drug solution does not leak out of the circuit and air (air bubbles) can be removed very easily. In the past, there was a risk of bacteria invading from the air contact part of the three-way stopcock, but this degassing plug has no rotating part, so there is no danger of bacteria invasion and it is highly safe. The present invention has been accomplished

The present invention is a hollow fiber in which a hydrophobic porous hollow fiber membrane is housed in a container, the end of the hollow fiber membrane and the container are liquid-tightly sealed with an adhesive, and the end of the hollow fiber is opened. In the membrane structure, the average pore diameter of the hydrophobic hollow fiber membrane is 0.0
The present invention relates to a degassing plug having a range of 5 to 0.8 μm. Further, in a membrane structure in which a hydrophobic porous flat membrane is housed in a container and the periphery of the flat membrane and the container are liquid-tightly sealed with an adhesive or heat, the average pore diameter of the hydrophobic membrane is 0. The present invention relates to a degassing plug having a range of 05 to 0.8 μm. The present invention also relates to a degassing plug in which a check valve is provided at the end of the degassing plug.

When the degassing plug of the present invention is made of a porous hollow fiber membrane, the volume can be designed to be small relative to the ratio of the membrane area, so that the degassing plug itself can be made small.
The priming amount of blood and drug solution decreases with respect to the degassing rate.

When the degassing plug of the present invention is formed of a porous flat membrane, the volume is larger than that of the hollow fiber with respect to the ratio of the membrane area, but the adhesive portion can be designed to be small, so that the structure is simple. . The material of the hydrophobic porous hollow fiber membrane used for the degassing plug of the present invention may be any hydrophobic polymer, such as polypropylene, polyethylene and poly (4-
Methyl pentene-1), polyolefin such as polystyrene, polyfluoroethylene, condensation polymer such as polyester and nylon, and polycarbonate. Further, it is necessary to be able to sterilize, and it is necessary to be able to perform sterilization by any one of high pressure steam sterilization, sterilization by EOG sterilization chemicals, γ-ray sterilization, and electron beam sterilization.

The method of making porous is a method of producing a hollow raw fiber or a raw material of crystalline polyolefin, and then stretching it under a predetermined condition to produce a porous membrane, and extracting a polymer mixed with a pore-forming agent. Then, any method such as a method of producing a porous film in which the extraction portion has pores, a method of irradiating radiation and then extracting the deteriorated portion may be used.

The pore size of the porous membrane is 0.05 to 0.8 μm. Further, the porosity, which represents the ratio of the volume occupied by the pores in the entire volume of the film, is preferably 20% or more and 80% or less. If the pore diameter of the porous membrane is smaller than 0.05 μm, the amount of permeation of air will be small and the size of the degassing plug will be large even if the porosity is large, which is not preferable. Further, if it is larger than 0.8 μm, the permeation amount of air becomes large, which is preferable, but there is a possibility that bacteria may invade. As the size increases, not only bacteria invade but also liquids pass through even if the material is hydrophobic.

The outer diameter of the porous hollow fiber membrane is 100 to 1000.
μm, and the inner diameter is preferably 130 to 970 μm. These ranges are determined only by being adopted within a range that depends on the difficulty of manufacturing the hollow fiber membrane and manufacturing of the degassing plug, and are not particularly related to the performance as the degassing plug. However, if the inner diameter of the hollow fiber is extremely thin, that is, 100 μm or less, resistance to air flow is generated, which is not preferable. Further, when the wall thickness of the hollow fiber or the flat membrane is extremely large, such as 100 μm or more, resistance to air flow is generated, which is not preferable. Further, if the wall thickness of the hollow fiber or the flat membrane is extremely thin at 15 μm, the strength of the membrane itself is lowered, which is not preferable.

The structure of the degassing plug of the present invention is such that the hydrophobic porous hollow fiber membrane is housed in a container, and at least one end of the hollow fiber is liquid-tightly sealed with the container and an adhesive, and the hollow fiber end is opened. It has a special structure. The structure of the container for housing the porous hollow fiber membrane may be such that the end of the hollow fiber can be liquid-tightly sealed with the container, and at least one end is attached to the end or vent of the blood circuit, or It should have a structure that can be fixed. The shape may be a molded product, a pipe, a tube, or the like. An example of the shape is shown in FIG.
Shown in In (1a), a hollow fiber bundle having both ends opened is bent into a U shape, housed in a container, and sealed at a sealing portion 5, and the other end is easily removable from a circuit device. In this example, the diameter is reduced toward the tip. (1c) becomes (1
This is an example in which the mounting portion of a) is extended and bent at a right angle.
(1b) is an example in which hollow fibers having open ends are linearly housed in a container, both ends are sealed, and the central part is connected to the mounting part.

The structure of the container for accommodating the porous flat membrane may be such that it can be liquid-tightly sealed with the flat membrane, and at least one end is attached to or fixed to the end of the blood circuit or the degassing part. Any structure is acceptable. The shape may be a molded product, a pipe, a tube, or the like.

The material of the container is polycarbonate, A
S resin, polyvinyl chloride, ABS resin, polysulfone, etc. can be appropriately selected in consideration of safety to blood, adhesiveness with an adhesive, deterioration resistance due to sterilization, and the like. The adhesive that liquid-tightly seals the porous film and the container may be one-component or two-component. However, it is necessary that it is safe for blood, that its adhesiveness is not impaired by priming liquid or blood, and that it is not impaired by sterilization. In the case of a flat membrane, it is also possible to bond it to the container by heat.

The degassing plug of the present invention has an average pore size of 0.0.
Since it is composed of a hydrophobic membrane in the range of 5 to 0.8 μm, an aqueous liquid or blood does not enter the pores of the membrane even at a pressure of ^{2 to} 15 kg / cm ² . In the actual medical field, the pressure when priming and flowing blood is 100 mmHg ~
Since the pressure is several hundred mmHg, the aqueous liquid and blood do not leak out of the degassing plug through the pores of the membrane or the membrane to the outside. In addition, a membrane in this pore size range can prevent bacterial invasion.

A check valve can be provided in the degassing plug. By providing a check valve at the end of the degassing plug opposite the blood circuit or the blood side of the catheter, it is possible to prevent the inflow of air even if the blood circuit becomes negative pressure.
The check valve allows only the direction of air flow from the circuit or catheter side to the outside through the degassing plug.
The structure does not matter as long as it has a function of preventing circulation in the opposite direction.

The shape of the main degassing plug provided with a check valve is shown in FIG. Examples thereof include soft rubber and resin having a lead-like structure (2a), a spherical valve (2b), and a structure in which two thin films are stacked (2c). By providing the check valve 3, the degassing plug can be attached to the circuit or the catheter not only when the blood circuit or the catheter is primed but also when the blood circuit or the catheter is used. This not only prevents the inflow of gas from the outside, but also enables the microbubbles in the blood to be constantly removed from the circuit or catheter.

[0020]

[Example] As a hydrophobic porous hollow fiber membrane, a polypropylene porous hollow fiber membrane produced by a stretching method (Ube Industries, Ltd.)
The product name Rectan) was used. This porous hollow fiber membrane has an average pore size (measured by the bubble point method) of 0.12μ.
m, the outer diameter of the hollow fiber is 450 μm, the inner diameter is 350 μm, and the porosity is 70% (measured by mercury porosimetry). A 10 cm long porous hollow fiber membrane bundle is folded into two and inserted into a 6 cm long polycarbonate pipe-shaped container, and the porous hollow fiber bundle and the container are liquid-tightly sealed using a polyurethane adhesive. ,
Furthermore, the hollow fiber end was opened. The membrane area of the porous hollow fiber membrane of the degassing plug was 38 cm ² . Attach this degassing plug to the end of the blood purification blood circuit and add 2
When introduced by a drop of 00 cm, air was completely removed from the inside of the circuit and the circuit was filled with physiological saline. No leakage of physiological saline was observed from the degassing plug. Further, a pressure of 5 kg / cm ² was applied to this circuit, but no leakage of physiological saline from the degassing plug was observed. After 3 days in the blood circuit equipped with this degassing plug, no bacterium or fungus was found in the saline solution, but the saline solution was not equipped with the degassing plug at the end (open state). Bacteria and fungi were found under the same conditions in the blood circuit filled with.

[0021]

INDUSTRIAL APPLICABILITY The present invention is simpler and safer than conventional methods by using a degassing plug made of a hydrophobic porous hollow fiber membrane having a specific average pore diameter or a hydrophobic porous flat membrane. In this way, the air in the blood circuit can be surely removed.

[Brief description of drawings]

FIG. 1 is an example of a perspective view of a degassing plug.

FIG. 2 is an example of a perspective view of a degassing plug provided with a check valve.

[Explanation of symbols]

 1 Porous Hollow Fiber Membrane Bundle 2 Mounting Part 3 Check Valve 4 Opening 5 Sealing Part

Claims (3)

[Claims] 1. A container containing a hydrophobic porous hollow fiber membrane,
In the hollow fiber membrane structure in which the end of the hollow fiber membrane and the container are liquid-tightly sealed with an adhesive and the end of the hollow fiber is opened, the average pore diameter of the hydrophobic hollow fiber membrane is 0.05 to
A plug for degassing a liquid circuit, which is in the range of 0.8 μm. 2. A membrane structure in which a hydrophobic porous flat membrane is housed in a container and the peripheral portion of the flat membrane and the container are liquid-tightly sealed by an adhesive or heat, and the average pore diameter of the hydrophobic membrane. Is in the range of 0.05 to 0.8 μm, a plug for degassing a liquid circuit. 3. The liquid circuit degassing plug according to claim 1 or 2, wherein a check valve is provided at an end of the liquid circuit degassing plug.