JPH0759849A - Blood filter in common use as blood dialyzer - Google Patents

Abstract

PURPOSE:To make it possible to obtain blood dialysis and blood filter function by joining a blood dialyzer and a blood filter. CONSTITUTION:The housing H of the dialyzer D of a hollow yarn type is formed in its shape to a length of about 10 to 15 times and more particularly about 12 times the bore 1. The hollow yarn F having excellent material permeability exists therein. The hollow yarn is introduced between a blood inlet 1 and blood outlet 2 disposed at both ends of the housing H and is formed in its shape to a length of about 10 to 15 times and more particularly about 12 times the diameter 1. As a result, the blood filtration which is heretofore executable only with the conventional device to be exclusively in an ordinary blood dialyzer can be executed; in addition, the need for a large volume of replenishing of a transfusion agent is eliminated. Consequently, the easy removal of middle- and high-mol.wt. materials without spending specific costs is possible and further, the ability to remove low-mol.wt. materials is improved and blood clotting is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to medical equipment, and more particularly to a hollow fiber type dialyzer. In particular, the present invention relates to a dialyzer having the functions of both a hemodialyzer and a hemofilter with one device.

[0002]

2. Description of the Related Art A dialysis-type artificial kidney (hemodialyzer) based on the principle of dialysis (concentration gradient) is generally used as a method for artificially removing waste products from blood in the human body.
Filtered artificial kidneys (blood filters) are also used in some areas as a powerful means of removing medium and high molecular weight substances.

[0003]

Although hemodialysis is excellent in removing low molecular weight substances, it is inferior in the ability to remove medium and high molecular weight substances. On the other hand, hemofiltration is excellent in removing medium and high molecular weight substances, but inferior in removing low molecular weight substances. Also,
Hemofiltration requires a large volume of infusion of 10-20 liters of infusion. Further, a device for appropriately controlling the balance between the filtration amount and the replacement fluid amount is required, and the operation for treatment is complicated and the treatment cost is high.

[0004]

In view of the above problems, the hemodialyzer / hemofilter according to the present invention makes use of the advantages of hemodialysis and hemofiltration and eliminates their respective disadvantages. That is, conventionally, hemodialysis and hemofiltration each require a dedicated hollow fiber and device. In the present invention,
Although the hemodialysis filter of the present invention is used as a hemodialysis device to obtain hemodialysis and hemofiltration performance, it does not require a large amount of replacement fluid as in conventional hemofiltration.

Specifically, a membrane having excellent substance permeability is used in the hollow fiber hemodialyzer, and the internal resistance of the dialyzer to the flow of blood is greatly increased as compared with the conventional hemodialyzer, so that the inlet of the dialyzer is increased. At the outlet side of the dialyzer, water is returned to the blood by back filtration to balance the filtration amount. For this reason, it is no longer necessary to replenish the infusion solution, and it has become possible to perform hemodialysis and hemofiltration simultaneously with a conventional hemodialysis apparatus.

Thus, in order to increase the internal resistance of the blood system and dialysate system of the hollow fiber dialyzer, the conventional dialyzer had a ratio of the inner diameter to the length of about 1: 5. Is 1:10 or more. As a result, the cross-sectional area of the dialyzer can be made smaller than the conventional one, its length can be made longer than the conventional one, and its internal resistance is greatly increased. As a result, the pressure on the inlet side of the dialyzer is high, and the pressure on the outlet side is low, so that filtration and back filtration occur significantly.

The specific construction of the hemodialyzer / hemofilter according to the present invention will be described in detail below. First, in the hollow fiber type dialyzer, there is a dialyzer housing. The shape of the housing is such that the length is about 10 to 15 and especially about 12 with respect to the inner diameter 1. And there is a hollow fiber. This hollow fiber is inserted between the blood inlet and the blood outlet provided at both ends of the housing, and its shape is such that the length is about 10 to 15 and especially about 12 to the diameter thereof. Is.

[0008]

The hemodialyzer / hemofilter according to the present invention has the following effects because it has the above-described configuration. That is, the pressure of blood in the hollow fiber on the inlet side in the dialyzer increases, and conversely, the pressure of blood in the hollow fiber on the outlet side decreases. Therefore, blood is actively filtered on the inlet side of one dialyzer, and water in the dialysate is returned to the blood by counter filtration on the outlet side of the dialyzer to balance the filtration amount. .

On the other hand, low molecular weight substances are removed by hemodialysis, and medium and high molecular weight substances are removed by hemofiltration.

[0010]

The contents of a hemodialyzer / hemofilter according to the present invention will be described below in detail with reference to an embodiment thereof.
First, in the hollow fiber type dialyzer D, there is a housing H of the dialyzer. This housing H
Has a shape whose length is 10 to 10 with respect to its inner diameter 1.
The ratio is about 15, especially about 12.

Then, there is a hollow fiber F having excellent substance permeability. The hollow fiber F is inserted between the blood inlet 1 and the blood outlet 2 provided at both ends of the above-mentioned housing H, and its shape has a diameter of 1 and a length of 10 to 15.
The ratio is about 12 in particular. On the other hand, the dialysate enters through the dialysate inlet 3 and exits through the dialysate outlet 4. As a matter of course, the dialysate must be sufficiently cleaned so that it can be subjected to back filtration.

[0012]

Since the hemodialysis by the hemodialyzer / hemofilter according to the present invention is performed as described above, the following great effects are brought about. First, hemofiltration, which was conventionally only possible with a dedicated device, can be performed only with an improved hemodialysis device, and there is no need for fluid replacement. As a result, it has become possible to easily remove the medium and high molecular weight substances without any special cost. Furthermore, the ability to remove low molecular weight substances was also improved.

As described above, in the hollow fiber hemodialysis / hemofilter, since the shape has a hollow fiber length of 10 or more with respect to an inner diameter of 1, when the pressure at the blood inlet side of this dialyzer is 200 mmHg, The pressure on the blood outlet side is 20 mmHg
Met. On the other hand, the dialysate had an outlet pressure of 0 mmHg when the inlet pressure was 100 mmHg. For this reason, water in the blood is filtered toward the dialysate side at the blood inlet side of the dialyzer, while reverse filtration occurs from the dialysate side into the blood at the outlet side. Thus, by hemofiltration, it is more effective than conventional hemodialysis.
The ability to remove high molecular weight substances was greatly improved.

On the other hand, the cross-sectional area of the inner diameter of the dialyzer is made smaller than that of the conventional one so that the length of the dialyzer can be made longer. As a result, the flow rate of blood and dialysate is increased, and the resistance to substance diffusion of the dialysis membrane is reduced, resulting in low molecular weight The ability to remove substances was also improved.
The blood coagulation could be prevented by increasing the blood flow velocity. In addition, as a matter of course, the dialysate must be sufficiently cleaned so that it can be subjected to back filtration.

Furthermore, a device for appropriately controlling the balance between the filtration amount and the replacement fluid amount is not required, the operation for treatment is not complicated, and as a result, the treatment cost is low.

[Brief description of drawings]

FIG. 1 is a side view of a hemodialyzer / hemofilter according to the present invention.

FIG. 2 is a graph showing water filtration from blood and back filtration of water into blood in the hemodialyzer / hemofilter according to the present invention.

[Explanation of symbols]

 1 blood inlet 2 blood outlet 3 dialysate inlet 4 dialysate outlet D dialyzer F hollow fiber H housing

Claims (1)

[Claims] 1. A hollow fiber type dialyzer whose shape has a length of about 10 to 15 with respect to an inner diameter of 1, especially 1.
A housing of a dialyzer having a ratio of about 2 times, which is inserted between a blood inlet and a blood outlet provided at both ends of a housing of the dialyzer, the shape of which is 10 to 15 in length with respect to its diameter. A hemodialyzer / hemofilter, which is characterized by comprising hollow fibers having a ratio of about 12, in particular.