JPH1033667A - Hollow fiber type fluid treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hollow fiber type fluid treatment device which is excellent in operability with a small size, remotely controllable, when set near a patient as, for example, a pump-oxygenator integrated with a centrifugal pump, and extremely highly practical by providing an inner cylinder having a communicating hole between a liquid flow generating part and the outer space of a hollow fiber membrane. SOLUTION: A pump-oxygenator which is one example of a hollow fiber type fluid treatment device has a housing 1, a blood inlet port 2, a blood outlet port 3, and an annular hollow fiber membrane 4, and the hollow fiber membrane end parts are adhered by a potting material to form an upper bulkhead 5 and a lower bulkhead 6, which are supported and fixed so as to open both the ends. The hollow fiber membrane 4 is cylindrically or annularly arranged to constitute a gas exchange part 7, and a hole 14 communicating with an inner cylinder 13 is provided between the hollow fiber membrane outer space part and a liquid flow generating part 12. Carbon dioxide in the blood supplied from the outside of the hollow fiber membrane 4 is exchanged with oxygen carried in the hollow fiber membrane 4 through the hollow fiber membrane 4 in the gas exchange part 7, and the blood to which oxygen is added is returned into the body of a patient.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fluid processing apparatus using a membrane. This type of device is generally used for oxygenator, hemodialysis device, plasma separator, humidifier, etc.
Here, for convenience, an artificial lung, which is an example of a blood processing apparatus for processing blood, will be described as a representative example.

[0002]

2. Description of the Related Art An artificial lung substitutes a gas exchange function of adding oxygen to blood and removing carbon dioxide among the functions of a living lung, and is researched and developed as an auxiliary means for open heart surgery. At present, the bubble-type oxygenator and the membrane-type oxygenator are in practical use.

[0003] In a membrane oxygenator, venous blood and gas are brought into contact with each other across a membrane to increase the oxygen concentration of the venous blood,
It releases carbon dioxide into the gas, and has advantages such as being closer to a living lung, less blood damage, and a smaller priming volume than a bubble type oxygenator, and is used frequently in clinical practice. It has become.

[0004] The membrane-type oxygenator currently used uses a hollow hollow fiber membrane made of a hydrophobic polymer such as polyolefin or a homogeneous hollow fiber membrane having high gas permeability such as silicon to form a hollow fiber membrane. Blood and gas are brought into contact with each other, and gas is exchanged between them. There are two types of internal perfusion type and external perfusion type. The internal perfusion type is a system in which blood flows in the hollow portion of the hollow fiber and gas flows outside the hollow fiber. For example, Japanese Patent Application Laid-Open Nos. 59-57661 and 62-106770 disclose the method. Specific examples are disclosed. On the other hand, the external perfusion type, on the other hand, is a system in which a gas flows in the hollow portion of a hollow fiber and blood flows to the outside. For example, JP-A-59-57963, JP-A-60-28806. Examples can be found in the official gazette and the like. Recently, an external perfusion type in which blood flows outside the hollow fiber is often used from the viewpoint of avoiding blockage of the hollow portion by blood coagulation.

Further, at present, efficient devices such as a device in which an artificial lung is combined with a blood pump such as a centrifugal pump and an integrated device are being pursued, and miniaturization of the device and system has been studied. (See, for example,
64662, JP-A-5-177117, etc.).

[0006]

The integrated device in which the artificial lung and the centrifugal pump are integrated is small in size and excellent in operability, so that it can be installed near a patient and remotely operated. However, in the external perfusion-type oxygenator, simply arranging the hollow fiber membrane around the centrifugal pump does not concentrate the blood flow due to the centrifugal force generated by the centrifugal pump, and tends to cause drift (channeling). In the part where the flow of blood has stopped due to the drift, problems such as thrombus formation occur,
Increased pressure loss, damage to blood, as well as reduced performance and secondary problems such as thrombus scattering,
Problems have arisen with remote control near the patient.

[0007]

Means for Solving the Problems The present inventors have studied the above problem in detail and found that the drift is mainly caused by the flow of blood mainly due to the centrifugal force generated by the centrifugal pump being dispersed from the gap between the hollow fiber membranes. The blood flow generated by the centrifugal pump is converged, and the hollow fiber membrane is evenly distributed on the hollow fiber membrane. The inventors of the present invention have found that the above problem is solved by the distribution, and have reached the present invention.

That is, the present invention provides a hollow fiber type fluid treatment apparatus in which a liquid flow generating means for continuously supplying a fluid to the hollow fiber membrane is disposed inside a fluid treatment apparatus in which the hollow fiber membrane is arranged in a cylindrical or annular shape. The hollow fiber type fluid treatment device is characterized in that an inner cylinder having a communication hole is provided between the liquid flow generation part provided with the liquid flow generation means and the hollow fiber membrane outer space.

The hollow fiber type fluid treatment apparatus of the present invention is essentially a gas exchange section formed by arranging hollow fiber membranes in a cylindrical or annular shape, and continuously supplies fluid to the hollow fiber membranes. It is composed of a liquid flow generating section provided with a liquid flow generating means, and an inner cylinder having a communication hole for communicating the outer space of the hollow fiber membrane in the gas exchange section with the liquid flow generating section.

In the present invention, the hollow fiber membrane is arranged in a cylindrical or annular shape. In the artificial lung, which is an example of the hollow fiber type fluid treatment apparatus shown in FIG. 1, an example in which hollow fiber membranes are arranged in a ring shape is exemplified, and an annular one in which the hollow fiber membrane is elongated in the longitudinal direction is cylindrical. The term “cylindrical or annular” in the present invention includes not only a perfect circular shape but also a slightly deformed shape such as an elliptical shape. The arrangement of the hollow fiber membranes is, for example, as shown in FIG. 3 of Japanese Patent Application Laid-Open No. 5-177117, an arrangement in which the hollow fibers are arranged in a single row in the direction of a cylindrical or annular central axis. As shown in Figure 5 of the book,
There are a variety of arrangements, such as staggered arrangements, as shown in FIG. 1 of the present invention, but are not limited to these.

The liquid flow generating means for continuously supplying the fluid to the hollow fiber membrane may be any means capable of continuously supplying the fluid, and the magnetic coupling type centrifugal pump and the rotating shaft may be a motor. Centrifugal pump fixed to the drive unit, such as
Examples include a cone type centrifugal pump such as a friction pump and a biopump.

The hollow fiber type fluid treatment apparatus of the present invention has a great feature in that an inner cylinder having a communication hole for communicating the hollow fiber membrane outer space in the gas exchange part with the liquid flow generation part is provided. By appropriately arranging such communication holes in the inner cylinder, a fluid such as blood is uniformly distributed from the liquid flow generating means to the hollow fiber membrane without causing drift.

The shape of the communicating hole is not particularly limited. However, when the fluid is blood, a circular or elliptical non-angular shape is preferable because the blood is hardly damaged. In the case of a communication hole having an elongated shape, it is more effective and preferable to arrange the communication hole in a direction in which the longitudinal direction of the communication hole and the axial direction of the hollow fiber intersect.

If the total area of the communication holes is S and the total fluid contact area of the inner cylinder is St, the fluid is evenly distributed if S / St is less than 0.005 and greater than 0.3. 0.005 ≦ S
/St≦0.3 is preferable.

If the number of communication holes is too small or too large, the effect of uniformly distributing the fluid may be reduced.
It is preferred that ≦ 12. Hereinafter, the hollow fiber type fluid treatment apparatus of the present invention will be described more specifically with reference to the drawings.

[0016]

FIG. 1 is a sectional view of an artificial lung, which is an example of a hollow fiber type fluid treatment apparatus of the present invention, and FIG.
It is A sectional drawing. In the figure, 1 is a cylindrical housing, 2 is a blood inlet port having a blood inlet, and 3 is a blood outlet port having a blood outlet. Reference numeral 4 denotes a hollow fiber membrane arranged in an annular shape, and the ends of the hollow fiber are bonded with a potting material such as an epoxy resin to form an upper partition 5 and a lower partition 6.
And the hollow fiber is supported and fixed so that both ends are open. The hollow fiber membrane 4 is arranged in a cylindrical or annular shape,
The gas exchange unit 7 and the outer space of the hollow fiber membrane are formed.

8 is a gas inlet port having a gas inlet, 9
Is a gas outlet port having a gas outlet, and oxygen is usually used as a gas. The carbon dioxide in the blood supplied from the outside of the hollow fiber membrane exchanges gas with the oxygen flowing inside the hollow fiber membrane via the membrane in the gas exchange section 7, and the blood is added with oxygen and returned to the patient's body.

The material of the hollow fiber membrane is not particularly limited as long as it has gas permeability, and examples thereof include polyolefin resins such as polyethylene, polypropylene and poly-4-methylpentene-1, polytetrafluoroethylene, and the like. Resins such as polysulfone and silicone rubber having high oxygen gas permeability are used. Above all, the hollow fiber membrane made of polyolefin resin has a small thickness,
When formed in a cord shape, the hollow fibers are less likely to be crushed or deformed, which is preferable. The hollow fiber membrane may be a porous membrane or a homogeneous membrane.

The outer diameter of the hollow fiber membrane is usually 50 to 2000 μm.
m, and the film thickness is 3 to 500 μm. If the outer diameter or the film thickness is too small, thread breakage or yarn cracking is likely to occur when forming into a cord or winding around a core, while if it is larger than this, it is difficult to realize compactness of the device. Preferably,
The outer diameter of the hollow fiber membrane is 100 to 500 µm, and the thickness is 6 to 10
0 μm.

In the external perfusion oxygenator, the hollow fiber membrane is
It is wound around the inner cylinder and accommodated in the outer cylinder. As shown in FIG. 1, one or a plurality of hollow fiber bundles arranged in parallel are formed into warp-shaped one-pieces. Even if the hollow fiber sheet is continuously wound around the inner cylinder, or two cord-shaped hollow fibers are wound around the inner cylinder in a state where the upper and lower hollow fibers are stacked alternately at an angle. Alternatively, one or a plurality of hollow fibers may be wound directly so that the hollow fibers alternately have an angle with the inner cylinder serving as the core. In this case, adjacent hollow fibers can cross each other, and the blood drift is further improved.

In order to form the hollow fiber into a cord, the hollow fiber may be braided with the warp or the warp may be bonded to the hollow fiber. It is preferable because it is easy to prepare the gate. When used for medical purposes, such as an artificial lung, it is necessary to select one in which the warp or adhesive does not damage the blood. Although any knitting method may be used to braid the hollow fibers with the warp in the form of a warp, it is preferable to fix the hollow fibers one by one with the warp, as in the case of chain knitting, since they can be firmly fixed.

The warp for forming the hollow fiber in a cord shape is not particularly limited, but examples thereof include polyester, polyamide,
Polyimide, polyacrylonitrile, polyethylene, polypropylene, polyacrylate, polyvinyl alcohol
A thread with a high strength is used even if it is thin, such as a thread. Among them, 10 to 15 consisting of multifilaments
Since the yarn of polyester or polyamide of 0 denier, preferably 25 to 75 denier has both moderate softness and mechanical strength, it is less likely to damage the hollow fiber when it is processed into a blind shape. It is preferably used. When used in medical applications, the use of oils in warp yarns should be avoided as much as possible. It is necessary to use an oil agent that can

When the hollow fibers are wound directly around the inner cylinder in an alternately angled state, a plurality of outer cylinders for maintaining a clearance between the inner cylinder and the hollow fibers may be mounted on the inner cylinder,
Alternatively, it is preferable to provide a projection on the surface of the inner cylinder. In this manner, when each hollow fiber is fixed by the warp, it is possible to prevent the hollow fiber from being displaced by blood when the hollow fiber sheet is wound around the inner cylinder or during use, so that the hollow fiber is always kept between adjacent hollow fibers. Since the gap can be kept constant, drift can be almost completely prevented. A gas exchange unit is constituted by a laminate formed by winding a hollow fiber sheet in which a bundle of one or a plurality of hollow fibers is formed into warp by a warp and a hollow fiber membrane outer space.

The hollow fiber sheet formed in the shape of a cord is wound around the inner cylinder to form a laminate, and the blood flow path is maintained between the housing and the laminate of the hollow fiber sheet. Is stored in the housing. After housing the hollow fiber sheet laminate, the open end of the hollow fiber is filled with a high-viscosity resin, or the open end of the hollow fiber is closed by heat sealing or crushing, and then centrifuged. It is mounted on a bonding machine, and epoxy resin, polyurethane, silicone, or the like is injected into both ends thereof to perform predetermined curing, and then the outer end of the cured resin is cut to open the hollow fiber.

In the present invention, the liquid flow generating means comprises an impeller 10 for supplying blood by centrifugal force, and a driving portion 11 connected to the impeller and generating rotation by the magnetic force of an external driving device. You. As described above, the liquid flow generating means may be a magnetic coupling type centrifugal pump, a centrifugal pump having a rotating shaft fixed to a driving unit such as a motor, a cone pump such as a friction pump or a bio pump. Centrifugal pump or the like can be used. The portion where the impeller is arranged and the external space constitute a liquid flow generating portion.

More specifically, an impeller in which a plurality of blades are erected on a circular pedestal inside the inner cylinder at regular intervals from the center of the pedestal, and an external drive isolated at a lower portion of the inner cylinder. The drive unit that is rotated by the device is connected by a shaft, and the periphery of the shaft penetrating the partition below the inner cylinder is isolated by a seal method. The sealing method is not particularly limited, and an oil seal, a mechanical seal, or a modified form thereof is usually used in addition to the V-ring and the O-ring. As the liquid flow generating means, an axial flow pump can be used other than the centrifugal pump and the like.

[0027] The hollow fiber type fluid treatment apparatus of the present invention is provided with an inner cylinder having a communication hole for communicating the outer space of the hollow fiber membrane in the gas exchange section with the liquid flow generation section. In FIGS. 1 and 2, reference numeral 13 denotes an inner cylinder, and a hole 14 for communicating the outer space of the hollow fiber membrane with the liquid flow generating portion is provided in the inner cylinder. As described above, the shape of the hole is preferably a shape that does not damage blood, such as a circle or an ellipse. The holes are provided along the circumference of the inner cylinder, but may be provided in a single row or in multiple rows.

The upper end of the housing is a blood inlet port 2
The lower end of the housing is covered with a lower head cover 16 having a gas outlet communicating with the internal space of the hollow fiber. In the artificial lung, the lower head cover 16 does not always need to be provided. In this case, the gas is released directly to the atmosphere from the end opening of the hollow fiber embedded in the partition.

In the above-mentioned artificial lung, the heat exchanger and / or
Alternatively, the blood reservoir can be integrated. FIG. 3 is a cross-sectional view of an artificial lung in which a heat exchanger is built, and is an example in which a heat exchanger 18 having a heat transfer tube is accommodated around the inner cylinder. The heat transfer tube is wound around the inner cylinder concentrically with the hollow fiber membrane, and both ends are embedded in a partition wall that closes both ends of the cylindrical housing, supported by the partition wall, and opened. A pipe is connected to each of the openings, and an inlet 20 and an outlet 21 for warm water are provided at an end of the housing.

FIG. 4 is a sectional view of an artificial lung having a built-in blood reservoir, in which blood flowing out from an opening provided at an upper portion of the housing between the outer periphery of the cylindrical housing and the outer wall of the housing is stored. A tank 19 is provided. An outlet for blood is provided at the upper part of the blood reservoir. Combining an artificial lung with a built-in heat exchanger and an artificial lung with a built-in blood reservoir, heat exchanger-gas exchange unit-in the direction of blood flow.
It can also be configured to be a blood reservoir. Further, a coiled heat transfer tube is housed in the blood reservoir, the blood outlet at the upper part of the blood reservoir is connected to the blood inlet at the upper end of the cylindrical housing, and the blood reservoir, the heat exchanger, and the gas exchange part are arranged in this order. You may.

The device of the present invention is used not only for an artificial lung but also for many other fluid treatment devices. For example, examples of its use are shown in dialysis in which mass transfer between two different liquids is performed via a hollow fiber and gas separation in which mass transfer is performed between two different gases via a hollow fiber membrane. Can be. In the case of dialysis, two kinds of liquids may flow inside or outside the hollow fiber, but it is preferable to flow the liquid containing the substance to be dialyzed outside the hollow fiber. In the case of gas separation, two kinds of gases may be flowed either inside or outside the hollow fiber. In the filtration or concentration of a liquid or a gas in which a specific substance contained in the gas or the liquid is separated by the hollow fiber, the liquid or the gas may flow into the inside or the outside of the hollow fiber.

[0032]

【Example】

Examples 1 to 15 Using poly-4-methylpentene-1 as a film material, having a dense layer of 0.5 μm on the outer surface, an outer diameter of 255 μm, and an inner diameter of 2
The hollow fiber membranes having a length of 05 μm are arranged one by one so that the hollow fiber density in the longitudinal direction is 21 fibers / cm, and a polyester yarn of 30 denier 12 filaments is used as a warp yarn. cm, the hollow fiber membrane was chain-knitted in a cord-like fashion to produce a cord-like hollow fiber membrane sheet.

The hollow fiber membrane sheet is wound around a polycarbonate inner cylinder (winding part diameter: 43 mm) in which three communicating holes each having a round hole having a diameter of 5 mm are uniformly provided to form a laminate. ,
A gas exchange section having a membrane area of 0.8 m ² (hollow fiber sheet width: 22 mm) was constituted and housed in a polycarbonate housing having an inner diameter of 60 mm. Both ends of the laminate were fixed between the housing and the inner cylinder with epoxy resin so that both ends of the hollow fiber membrane were open. The clearance between the inner cylinder and the laminate, and between the housing and the laminate was 3 mm.

The inside of the inner cylinder is made of polycarbonate having a diameter of 7 mm.
0 mm, 6 blades, a semimicrose type centrifugal pump is inserted, and a rotating body provided with a magnet in a space separated from the blood flow path is installed at the lower end of the housing, and the rotating body and the impeller of the centrifugal pump are mounted. They were connected by a stainless steel shaft to form a liquid flow generating means.

A hollow fiber type processing apparatus as shown in FIG. 1 was prepared, and using bovine blood heated to 37 ° C., blood and pure oxygen were adjusted so that the ratio of oxygen flow rate to blood flow rate became 1.0. Shed
The performance was evaluated in accordance with the proposed artificial lung performance evaluation standard (Japan Society for Artificial Organs). Those with low pressure loss and high maximum blood flow per unit membrane area were evaluated as high-performance oxygenators. In Tables 1 to 3, the hole diameter is the diameter of the round hole. Table 1 shows the results.

[0036]

[Table 1]

Examples 16 to 43 The same experiment as in Examples 1 to 15 was performed using the same hollow fiber membrane sheet as in Example 1 and changing the shape of the hole of the inner cylinder. The opening area of the hole was 2.4 cm ^{2 for} all the artificial lungs. In addition,
In the number of holes in Table 2, for example, a display of 6 (3 * 2) means that three round holes are arranged in two rows vertically and a total of six round holes are formed. The results are shown in Tables 2 and 3.

[0038]

[Table 2]

[0039]

[Table 3]

Examples 44 to 46 The same experiment as in Examples 1 to 15 was performed using the same hollow fiber sheet as in Example 1 and changing the area of the hole of the inner cylinder. In the hole diameters shown in Table 4, for example, 0.2 * 1 * 3 axis indicates a rectangular hole having a short axis diameter of 0.2 cm and a long axis diameter of 1 cm, and chamfering four corners. 3 so that it is in the axial direction of the cylinder
Means that they are arranged, 0.2 * 1 * 3 circumference is
It means that three rectangular holes with a short axis diameter of 0.2 cm and a long axis diameter of 1 cm are chamfered at four corners so that the long axis is in the circumferential direction of the inner cylinder. . Table 4 shows the results. An example in which the inner cylinder is not provided is shown as Comparative Example 1.

[0041]

[Table 4]

[0042]

According to the present invention, it is possible to provide a hollow fiber type fluid treatment apparatus having no drift. Since the hollow fiber type fluid treatment device of the present invention is small and excellent in operability, it can be installed near a patient and remotely controlled, for example, as an artificial lung integrated with a centrifugal pump, and is extremely practical. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a hollow fiber type fluid treatment device of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a cross-sectional view of an example in which a heat exchanger is provided in the hollow fiber type fluid treatment apparatus of the present invention.

FIG. 4 is a cross-sectional view of an example in which a blood reservoir is provided in the hollow fiber type fluid treatment apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Blood inlet port 3 Blood outlet port 4 Hollow fiber membrane 5 Upper partition 6 Lower partition 7 Gas exchange section 8 Gas inlet port 9 Gas outlet port 10 Impeller 11 Drive section 12 Liquid flow generation Part 13 Inner cylinder 14 Communication hole 15 Upper head cover 16 Lower head cover 17 O-ring 18 Heat exchanger 19 Blood reservoir 20 Hot water inlet 21 Hot water outlet

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takehiko Okamoto 1621 Sazu, Kurashiki-shi, Okayama Prefecture Inside Kuraray Co., Ltd.

Claims (3)

[Claims] 1. A hollow fiber type fluid treatment apparatus comprising a fluid treatment apparatus in which hollow fiber membranes are arranged in a cylindrical or annular shape and a liquid flow generating means for continuously supplying a fluid to the hollow fiber membranes. A hollow fiber type fluid treatment apparatus, wherein an inner cylinder having a communication hole is provided between a liquid flow generating portion provided with a liquid flow generating means and the outer space of the hollow fiber membrane. 2. The hollow fiber type fluid treatment apparatus according to claim 1, wherein a relationship between a total area S of the communication hole and a total fluid contact area St of the inner cylinder is 0.005 ≦ S / St ≦ 0.3. . 3. The hollow fiber type fluid treatment apparatus according to claim 1, wherein the number N of the communication holes is 1 ≦ N ≦ 12.