JPH0563214B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a hollow fiber type artificial organ for blood purification. More specifically, the present invention relates to a hemodialyzer, a hemodialysis device, a blood pressure-driven hemodialysis device, etc., which have excellent performance characteristics and stability, and are intended for the treatment of patients with chronic or acute renal failure. [Prior Art] Currently, intermittent hemodialysis or hemodialysis using a blood pump is generally performed as a treatment for patients with chronic renal failure. On the other hand, for the treatment of patients with acute renal failure caused by complications after surgery, etc., it is necessary to rapidly remove large amounts of water and solutes, which may not be possible with conventional intermittent treatment methods. many. Continuous hemodialysis or hemodialysis is effective in such cases, but since it is used continuously for about one day to two weeks, the membrane used for this requires strict blood compatibility, and It has been impossible to use conventional hemodialyzers and blood filters due to their structure or membrane characteristics. That is,
In conventional dialyzers and dialysis machines, not only their structure but also the membranes used are intended for blood purification in a short time of 4 to 5 hours, and therefore the membrane design focuses on overefficiency. Because of this, there was a drawback that blood clots were likely to form on the membrane surface if it was in contact with blood for a long time. Furthermore, it is not desirable to use a blood pump, which puts a heavy burden on the patient's heart when used continuously for a long period of time, and a treatment method that performs extracorporeal circulation using only the patient's own blood pressure, that is, a blood pressure-driven blood pump, is also being considered. , in this case blood flow fluctuations depending on the patient's blood pressure,
In particular, it has been impossible to use conventional blood purifiers because blood clots are likely to form within the membrane due to decreased blood flow. [Object of the Invention] The present inventors have developed a hollow fiber type blood system that can stably perform long-term continuous hemodialysis or hemodialysis as described above, as well as blood pressure-driven hemodialysis without using a blood pump. As a result of intensive research to obtain a purifier, it was discovered that a separation membrane with excellent performance could be obtained by using a specific resin and resin stock solution composition.Based on this knowledge, various studies were conducted and the present invention was developed. This is what led to this. [Structure of the Invention] That is, the present invention relates to a wet spinning method in which a hollow fiber manufacturing nozzle with a double tube structure is used, and a spinning dope is discharged from an outer annular opening and a coagulating liquid is discharged from a core into a coagulating bath and coagulated. , the spinning stock solution is polyether sulfone, polysulfone and solvent, and/or metal salt,
and/or a non-solvent, and the weight ratio of polysulfone to polyethersulfone is 1/9 or less. Hollow fibrous separation membranes typically have an inner diameter of 200 mm.
~300μm, and the film thickness can be made in the range of 10 to 100μm, but in order to improve the strength of the membrane and the filling rate when inserting it into the housing, the inner diameter of the membrane is 210 to 240μm.
The film thickness is preferably in the range of 30 to 50 μm. The polyether sulfone and polysulfone used in the present invention are each

〔Effect of the invention〕

As described above, the hollow fibrous separation membrane obtained from a specific resin stock solution composition containing polyethersulfone and polysulfone has a good balance between the surface condition of the membrane in contact with blood and blood overvelocity, that is, water removal ability. As a result, hemodialysis or blood filtration can be performed extremely efficiently and stably. Therefore, in the treatment of patients with chronic or acute renal failure, it is effective against long-term continuous hemodialysis or blood hyperemia, which was previously considered difficult, as well as blood hyperemia caused by blood pressure drive without the use of a blood pump. . Example 1 14% by weight of polyethersulfone, 1% by weight of polysulfone, 5% by weight of NaBr and 80% by weight of dimethylformamide were dissolved and mixed. Using this solution as a spinning dope, the spinning dope is discharged from the outer annular opening of the hollow fiber manufacturing nozzle, and water is discharged from the core, which is introduced into a coagulation bath consisting of water and coagulated at a speed of 40 m/min. I did the winding. Here, the spinning temperature, that is, the temperature of the spinning dope and the internal coagulation liquid, was 40°C. The rolled hollow fiber separation membrane was immersed in warm water at 60°C for 7 hours and then in running water for 10 hours. The obtained hollow fibrous separation membrane has an inner diameter of 220 μm and a membrane thickness.
It was 30μm. 3,000 of these hollow fibrous separation membranes were inserted into a cylindrical column made of polycarbonate, both ends of which were adhesively fixed with polyurethane, and then both ends were cut to obtain openings in the hollow fibrous separation membranes. The effective length of the hollow fibrous separation membrane was 10 cm. Next, an external shunt was placed in the cervical artery and vein of a mongrel dog weighing approximately 16 kg with ureteral ligation, and blood pressure-driven blood flow was performed. At that time, administer heparin at 400IU/
Continuous infusion was performed for several hours. As a result, 700-1500
A stable water removal rate of ml/hour was obtained, and continuous treatment for over 100 hours was possible, and the dog remained in good condition during this period. In the following Examples and Comparative Examples, unless otherwise specified, spinning, evaluation tests, etc. will be conducted in the same manner as in this Example. Example 2 Polyethersulfone 15% by weight, polysulfone
A spinning dope consisting of 1.5% by weight, 4% by weight of LiCl and 79.5% by weight of N-methyl-2-pyrrolidone was used.
The winding speed was 50 m/min. The obtained membrane had an inner diameter of 230 μm and a thickness of 35 μm. In a blood flow test using dogs, stable continuous flow for over 100 hours was possible with water removal of 900 to 1400 ml/hour. Example 3 15% by weight polyethersulfone, 1% by weight polysulfone, 3% by weight ethanol and N-methyl-
A spinning dope having a composition of 81% by weight of 2-pyrrolidone was used. In blood tests using dogs, both water removal ability and long-term stability were good. Comparative Example 1 A spinning dope consisting of 15% by weight of polyether sulfone, 5% by weight of NaBr and 80% by weight of dimethylformamide was used. In a blood test using dogs, the long-term stability was good, but the water removal ability was 600%.
The value was low, less than ml/min. This value indicates insufficient water removal ability for the symptoms of patients with renal failure. Comparative Example 2 A spinning dope consisting of 13% by weight of polyethersulfone, 2% by weight of polysulfone, 5% by weight of NaBr and 80% by weight of dimethylformamide was used. In the blood test, the blood pressure is 1000~5 hours after the start of the test.
Although it showed a high water removal capacity of 1,300 ml/hour, it rapidly decreased after 50 hours and became less than 100 ml/hour, so the experiment was discontinued. Thrombus was observed inside the hollow fibrous separation membrane used, and this was the cause of the decrease in water removal.

Claims (1)

[Claims] 1. Using a hollow fiber manufacturing nozzle with a double tube structure,
In the wet spinning method in which the spinning stock solution is discharged from the outer annular port and the coagulation solution is discharged from the core into a coagulation bath and coagulated, the spinning stock solution contains polyethersulfone, polysulfone, a solvent, and/or a metal salt, and/or a non-solvent. A method for producing a hollow fiber separation membrane, characterized in that the weight ratio of polysulfone to polyethersulfone is 1/9 or less. 2 The composition of the coagulating liquid is water, or water, metal salt and/or
The method for producing a hollow fibrous separation membrane according to claim 1, characterized in that the method comprises a solvent for the resin and/or a non-solvent for the resin. 3 Polyether sulfone and polysulfone are
[formula] and The method for producing a hollow fibrous separation membrane according to claim 1, characterized in that the hollow fiber separation membrane is made of a polymer having repeating units.