JPH05245195A - Blood filtration and dialysis device - Google Patents

Abstract

PURPOSE:To provide the blood filtration and dialysis device with a function to prevent the degradation in the performance of a membrane which lessens the change in the blood flow rate on an vein side, is simple in function and control and is inexpensive. CONSTITUTION:This blood filtration and dialysis device includes a filtering and dialyzing device 1, an artery side blood chamber 8, a vein side blood chamber 7 and an ultrafiltration rate controller 3 and is constituted by interposing a reciprocating pump 2 delineated with an air chamber 5 for a buffer and a dialyzate chamber 4 with a piston 6 in-between between a dialyzate outlet 9 of the filtering and dialyzing device 1 and the vein side blood chamber 7 and connecting the dialyzate outlet 9 and the dialyzate chamber 4, the air chamber of the vein side blood chamber 7 and an air chamber 5 for the buffer, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hemofiltration apparatus and, more particularly, to prevent a reduction in filtration efficiency due to clogging of a membrane of a filtration dialyzer without requiring a sterilized replenisher. The present invention relates to a hemodiafiltration device that can be used.

[0002]

2. Description of the Related Art Conventionally, hemodialysis, which removes small molecular weight substances by the principle of diffusion, and blood filtration, which removes medium molecular weight substances by the principle of ultrafiltration, have been combined to produce small to medium molecular weight substances. BACKGROUND ART A hemofiltration hyperdialysis device is known as a blood processing device capable of removing blood uniformly and efficiently. However, the conventional hemoperitoneal dialysis device requires a sterilized replenisher to replenish the body fluid lost by the filtration, and the performance of the membrane deteriorates in the process of blood purification (due to clogging of the pores of the membrane). The problem is that the filtration efficiency decreases). Therefore, in order to solve such a problem, a hemoperitoneal dialysis device has been proposed in recent years that does not require a sterilized replenisher and can prevent deterioration of the membrane. Instead of replenishing body fluid with sterilized replenisher, put dialysate in and out with the membrane of the peritoneal hyperdialyzer, that is, to prevent deterioration of membrane performance by putting dialysate in and out of blood. This is a so-called push-and-pull type hemodialysis device (Japanese Patent Application Laid-Open No. 61-25564, Japanese Patent Application Laid-Open No. 3-280963).

The one shown in FIG. 4 is disclosed in JP-A-61-2556.
In the blood circuit 22 on the blood outlet side of the filter hemodialyzer 21, the blood storage container 23 and the pump 24 are proposed.
The dialysate storage container 26 and the pump 27 are arranged in the dialysate circuit 25 on the dialysate outlet side of the peritoneal dialyzer 21 so that a certain amount of dialysate enters and leaves the blood. is there. According to such a configuration, the upper limit and the lower limit of the stored liquid amount are set by the load cells provided in each of the blood storage container 23 and the dialysate storage container 26, and the pumps 24, 27 are set at the limits of these set liquid amounts. By switching control of
The membrane can be washed while always maintaining a constant amount of liquid returned to the body through the hemodialysis filter 21 of the blood system, and the dialysate is pushed into the blood system and the corresponding water withdrawal is performed. Can be done in good balance.

Further, the structure shown in FIG. 5 is disclosed in Japanese Unexamined Patent Application Publication No. Hei 3 (1999) -311 in order to improve the drawback (complex structure and control) of FIG.
No. 280963, the dialysate system 3 before and after the dialysate inflow / outflow rate equalizing mechanism 38.
2 is provided with bypass flow passages 33 and 34, and switching between the bypass flow passages 33 and 34 is performed by switching valves 35 and 36, and a dialysate injection / withdrawal pump 37 is provided in the bypass flow passages 33 and 34. The dialyzer 31 is configured so that excessive injection and withdrawal of dialysate are alternately performed. According to such a configuration, the single dialysate injection / withdrawal pump 37 is used to inject and withdraw the dialysate, so that there is no deviation in the injection amount and withdrawal amount of the dialysate. Moreover, since a reservoir or the like for storing the dialysate is not required, highly accurate peritoneal dialysis can be performed with a simple configuration.

However, the structure shown in FIG. 4 is complicated in terms of mechanism and control and is disadvantageous in cost, and the structure shown in FIG. 5 has mechanical and control drawbacks. Although improved, it has the drawback that the blood flow on the venous side changes significantly when the dialysate is taken in and out.
In the hemodialysis device shown in FIG. 5, the blood flow volume on the venous side greatly changes when the dialysate is taken in and out, which imposes a great physical burden on the patient, and when the blood flow volume changes significantly, the shunt also has a large load. Therefore, the life of the shunt is shortened, and it is difficult to confirm whether the extracorporeal circulation of blood is normally performed because the blood volume is not stable.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has the advantage that the change in blood flow on the venous side is small, and is simple in terms of mechanism and control. It is an object of the present invention to provide an inexpensive hemoperitoneal dialysis device with a function of preventing deterioration of membrane performance.

[0007]

In order to solve the above problems, the present invention provides, as a first invention, a filter hemodialyzer, and blood inlet side (arterial side) and outlet side (the blood vessel side) of the filter hyperdialyzer. Blood chambers provided on the respective (venous side), and an ultrafiltration amount control device for controlling the volume difference between the fresh dialysate flowing into the filter hyperdialyzer and the used dialysate flowing out of the filter hyperdialyzer as the amount of water removal, In the hemodialysis device comprising and, between the dialysate outlet of the hemodialysis machine and the venous blood chamber,
A reciprocating pump, which is defined by a buffer air chamber and a dialysate chamber inside the cylinder with a piston in between, is interposed.
The dialysate outlet of the filter dialyser and the dialysate chamber of the reciprocating pump,
The hemodialysis device is characterized in that the air chamber of the vein side chamber and the buffer air chamber of the reciprocating pump are connected to each other. However, the fresh dialysate as used herein includes a replacement solution and a replacement solution-containing dialysate in addition to the dialysate.

As a second invention, the reciprocating motion of the piston of the reciprocating pump causes the dialysate in the dialysate chamber to be taken in and out, and when the dialysate is discharged, the blood is reverse-filtered and the dialysate is inhaled. The filtration and the filtration are alternately performed through the filtration dialysis membrane of the filtration dialyzer, and in the blood filtration process, air is moved from the buffer air chamber to the venous blood chamber, and the dialysate reverse filtration process is performed. In this method, air is moved from the venous blood chamber to the buffer air chamber, and the method for blood hemodialysis using the hemodialysis apparatus according to claim 1 is used.

[0009]

According to the above construction, when the piston of the reciprocating pump moves to the dialysate chamber side (push step), the dialysate enters the blood through the membrane of the filtration dialyzer, so that the blood is filtered. The clogging of the pores of the membrane, that is, the pores (the blood side of the pores of the membrane is clogged with a large molecular weight substance) that occurs during the process is resolved, and the blood lost due to filtration is replenished with water. The movement of air from the vein side chamber to the buffer air chamber prevents the fluid level in the vein side chamber from rising and the pressure on the vein side from becoming excessive, and the piston moves toward the buffer air chamber side. When moved (pull process), blood is filtered and air is moved from the buffer air chamber to the venous blood chamber, causing the liquid level in the venous blood chamber to drop and the venous pressure to be exceeded. Is prevented consisting of is to.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. 1 is a circuit diagram showing a hemodialysis hyperdialysis apparatus according to an embodiment of the present invention, and FIGS. 2 and 3 are explanatory views of a push step and a pull step in the operation of the hemodialysis hyperdialysis apparatus of FIG. 1, respectively. is there. As shown in FIG. 1, the hemodiafiltration apparatus of the present invention comprises a hemodialysis machine 1, an arterial blood chamber 8, a venous blood champer 7, and an ultrafiltration amount control device 3. In the device, between the dialysate outlet 9 of the peritoneal dialyzer 1 and the venous blood chamber 7,
The buffer air chamber 5 and the dialysate chamber 4 with the piston 6 in between.
The reciprocating pump 2 defined by the above is interposed, and the dialysate outlet 9 and the dialysate chamber 4, the air chamber of the venous blood chamber 7 and the buffer air chamber 5 are connected to each other. In the figure, 10 and 11 are filters for filtration, 1
2 is an air filter, 13 is a dialysate inlet, 14 is a blood inlet, 15 is a blood outlet, and 17 is a blood pump.

In the hemofiltration hyperdialysis apparatus having the above structure, the dialysate in the dialysate chamber 4 is taken in and out by the reciprocating motion of the piston 6 of the reciprocating pump 2, and the reverse filtration of blood when the dialysate is discharged. The filtration and the filtration of the blood when the dialysate is inhaled are alternately performed through the filtration dialysis membrane (16 in FIG. 2) of the filtration dialyzer 1, and in the blood filtration step, the buffer air chamber 5 is used. Air can be moved to the venous blood chamber 7, and in the dialysate reverse filtration step, air can be moved from the venous blood chamber 7 to the buffer air chamber 5.

In the hemodialysis device shown in FIG. 1, normally,
Blood is supplied from the blood pump 17 to the arterial blood chamber 8
Through the blood inlet 14 into the peritoneal dialyzer 1, where it is perforated and permeated through the blood outlet 15 to the venous blood chamber 7, and the fresh dialysate is filtered by the filter 11 for filtration. After that, it passes through the ultrafiltration amount control device 3 and the filtration filter 10 and flows into the filtration hyperdialyzer 1 from the dialysate inlet 13, and is used for filtration hyperdialysis. The used dialysate flows out from the dialysate outlet 9, passes through the ultrafiltration amount control device 3, and is discharged to the outside. The ultrafiltration amount control device 3 used here is the amount of fresh dialysate flowing into the filtration device 1 and the filtration device 1.
The difference in the amount of used dialysate flowing out from the device is controlled as the amount of water removed, and for example, Japanese Patent Publication No. 56-82 or
JP-A-57-66761, JP-B-3-54590
And the like, which are disclosed in Japanese Patent Publication No.

As shown in FIG. 2, when the piston 6 of the reciprocating pump 2 is moved to the right side of the figure, that is, the dialysate chamber 4 side (push step), the dialysate stored in the dialysate chamber 4 is Since the buffer air chamber 5 is expanded while flowing into the peritoneal dialyzer 1 from the dialysate outlet 9 and permeating the peritoneal dialysis membrane 16 into the blood, the blood on the venous side communicating with the buffer air chamber 5 is expanded. Air moves from the air chamber 18 of the chamber 7 to the buffer air chamber 5. Then, when the dialysate permeates the permeation membrane 16 and enters the blood, it is caused by the permeation of blood (at this time, the water in the blood permeates the permeation membrane 16 and goes out to the dialysate side). The clogging of the pores of the membrane (the blood chamber side of the pores of the membrane is clogged with a large molecular weight substance) is cleared by backwashing the dialysate (called backwashing). On the other hand, when the air in the air chamber 18 of the venous blood chamber 7 moves to the buffer air chamber 5, the liquid level of blood in the venous blood chamber 7 rises, so that the venous pressure does not become excessive (Table 1 reference).

As shown in FIG. 3, when the piston 6 of the reciprocating pump 2 is moved to the left side of the drawing, that is, to the buffer air chamber 5 side (pull step), the dialysate excessively injected into the blood ( (Accurately, including water in blood) permeates the peritoneal dialysis membrane 16 and is sucked toward the dialysate side, flows into the dialysate chamber 4 from the dialysate outlet 9, and is used for the buffer. Since the air chamber 5 is reduced, the buffer air chamber 5
The air chamber 1 of the venous blood chamber 7 communicating with the
Air movement to 8 occurs. Then, the dialysate permeates the peritoneal dialysis membrane 16 and enters the dialysate side to permeate blood, while the air flows from the buffer air chamber 5 to the air in the venous blood chamber 7 communicating therewith. By moving to the chamber 18, the liquid level of the blood in the venous blood chamber 7 is lowered, so that the venous pressure does not become too small (see Table 1).

[Test Example 1] Using a hemodialysis device as shown in FIG. 1, water removal rate on the patient side: 0 L / hr, blood flow on the arterial side: 200 ml / min, venous pressure (normal): about 16
0 mlHg, push / pull speed: 3.6 L / hour (replenishment speed: about 1.8 L / hour), when the buffer air chamber and the venous blood chamber were connected (Example) and when not connected (comparison) For example), when the fluctuation range of the venous pressure, the blood flow rate on the venous side, and the fluctuation of the liquid level of the blood chamber on the venous side were examined, the results shown in Table 1 were obtained. It can be seen that by using the hemodialysis device of the present invention, fluctuations in venous pressure and blood flow on the venous side are greatly improved.

[0016]

[Table 1]

[0017]

As is clear from the above description,
By adopting the hemodialysis device of the present invention, the blood flow on the venous side can be stabilized, thus reducing the burden on the circulatory system of the patient. In addition, it is easy to confirm whether the extracorporeal circulation of blood is normally performed. Furthermore, it is possible to provide an inexpensive hemoperitoneal dialysis device with a function of preventing deterioration of membrane performance, which is simple in terms of mechanism and control.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a hemodialysis device according to an embodiment of the present invention.

2 is an explanatory view of a push step in the operation of the hemodialysis hyperdialysis apparatus of FIG. 1. FIG.

FIG. 3 is an explanatory diagram of a pulling step in the operation of the hemodialysis hyperdialysis device of FIG. 1.

FIG. 4 is a circuit diagram of a conventional example.

FIG. 5 is a circuit diagram of another conventional example.

[Explanation of symbols]

 1 Filtration dialyzer 2 Reciprocating pump 3 Ultrafiltration volume control device 4 Dialysis fluid chamber 5 Buffer air chamber 6 Piston 7 Venous blood chamber 8 Arterial blood chamber 16 Filtration dialyzing membrane

Claims (2)

[Claims] 1. A filter hemodialyzer, blood chambers respectively provided on the blood inlet side (arterial side) and outlet side (venous side) of the filter hyperdialyzer, and fresh dialysate flowing into the filter hyperdialyzer. And an ultrafiltration device for controlling the volume difference of the used dialysate flowing out from the peritoneal dialyzer as a water removal amount, and a dialysate outlet and vein of the peritoneal hyperdialyzer. Between the side blood chambers, a reciprocating pump, which is defined by a buffer air chamber and a dialysate chamber with the inside of the cylinder sandwiching the piston, is interposed, and the dialysate outlet of the peritoneal dialyzer and the dialysate of the reciprocating pump. And a blood chamber of a vein side chamber and a buffer air chamber of a reciprocating pump, respectively. 2. The reciprocating motion of the piston of the reciprocating pump causes the dialysate in the dialysate chamber to be taken in and out, and the reverse filtration of blood when the dialysate is discharged and the filtration of blood when the dialysate is inhaled. Alternately through the peritoneal dialysis membrane of the peritoneal dialysis machine,
In the blood filtration step, air is moved from the buffer air chamber to the venous blood chamber, and in the dialysate reverse filtration step, air is moved from the venous blood chamber to the buffer air chamber. A method for blood hemodialysis using the hemodialysis apparatus according to claim 1.