JP2001000541A - Blood purification device with improved water removal control accuracy - Google Patents

Abstract

(57) [Problem] To provide a high-performance and highly-reliable blood purification apparatus with improved water removal amount control accuracy. For example, a weight measuring means for measuring a total weight of a dialysate container and a filtrate container, and an initial total weight measured at the start of blood processing from a measured value of a total weight of two containers measured by the weight measuring means. A control device for increasing and decreasing the rotation of the filtrate pump until the difference between the two values becomes zero while comparing the numerical value obtained by subtracting the measured weight value and the target water removal value that increases with the treatment time according to the set water removal amount is provided. The above object is achieved by a blood purification apparatus characterized in that:

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood purification apparatus in which blood is supplied to a blood processing apparatus containing a semipermeable membrane to perform blood processing and return to a human body. It is about. The blood purification apparatus of the present invention can be suitably used for blood purification by extracorporeal circulation such as continuous slow hemodialysis, continuous slow hemodialysis, continuous slow hemofiltration, and hemofiltration.

[0002]

2. Description of the Related Art In a conventional blood purifying apparatus, in hemodialysis and hemofiltration by a continuous slow-removal method or the like, it is necessary to install a water removal drainage channel and a water removal pump in order to remove water from the human body. Was. The control of the water removal amount was flow rate control of the water removal pump, and the rotation speed of the water removal pump was kept constant with respect to the set water removal flow rate. Also, due to the flow rate error caused by the water removal pump, it was necessary to store the water removal in a container such as a measuring cylinder and actually measure the water removal. Such conventional devices have the following problems, and their solutions have been strongly demanded. The flow rate error of the water removal pump is large, and the accuracy is at most about ± 10%. Since a dedicated pump for removing water is required, the number of pumps is increased, and the blood circuit set in the apparatus is also complicated. Since it is necessary to measure the amount of water removed, work on site is complicated, and measurement errors and the like often occur.

As a method for improving the flow rate accuracy of the dewatering pump, there is a method of measuring the actual pump flow rate by a batch method and feeding back an error from the set flow rate to the pump rotation control. However, this method also has the following problems. There was a point. It takes time from setting the flow rate to performing the pump rotation control, and the flow rate error during that time cannot be corrected. If an error occurs in the actual flow rate measurement performed in the batch mode, the wrong pump rotation control is performed, which has a serious effect on the water removal control.

[0004]

SUMMARY OF THE INVENTION The present invention is directed to a blood purification apparatus which solves the above-mentioned problems of a conventional blood purification apparatus such as a continuous slow hemodialysis apparatus, that is, a. Improvement of water removal control accuracy. b. Simplification of circuit and improvement of operation performance by dedicated pump. c. Improved operability by eliminating actual measurement of water removal. d. Reliable water removal control and improved reliability through continuous control. It is an object of the present invention to provide a highly-functional and highly-reliable blood purification device that achieves the above.

[0005]

In order to solve the above-mentioned problems, the present inventor has tried various achievements, and in a conventional blood purifying apparatus such as a continuous slow blood processing apparatus, the actual removal of blood after blood processing has been performed. The emphasis is placed on improving the control accuracy of the water removal amount rather than visually measuring the water amount, and instead of the water removal method using a dedicated water removal pump, for example, a dialysate container, a replenisher container, and a filtrate container By using the weighing scale used for weight balance control and the filtrate pump for sending filtrate for water removal, the precision of water removal control can be improved to the order of weight accuracy (± 1%). In addition, since the weight balance control and the water removal control are continuously performed, the flow rate error can be eliminated, the reliable water removal control can be realized, and the number of pumps can be reduced by one. See that the point is resolved It is those issued. That is, the present invention provides a blood circulation path for introducing a patient's blood into a blood processor containing a semipermeable membrane and returning the blood to the patient again, a dialysate supply path for supplying a dialysate from a dialysate container to the blood processor. A replenisher supply for replenishing a patient with a replenisher from a replenisher via the blood discharge path for discharging spent dialysate from the blood processor to a filtrate container, or the blood circulation path, and the blood circulation path. From the blood passage, and the filtrate discharge passage for discharging the blood filtrate from the blood processor to the filtrate container, or from the blood circulation passage, the replenisher supply passage, the dialysate supply passage, and the blood processor. In a blood purification apparatus for performing hemodialysis or hemofiltration or hemofiltration dialysis, comprising a filtrate and a filtrate discharge path for discharging a spent dialysate to a filtrate container, the total weight of the dialysate container and the filtrate container is measured. Weight measuring means and two weights measured by the weight measuring means. The difference between the measured value of the total weight of the vessel and the value obtained by subtracting the measured value of the initial total weight measured at the start of the blood treatment and the target value of water removal that increases with the treatment time according to the set water removal amount is compared. A control device for increasing or decreasing the rotation of the filtrate pump until it becomes zero, or a weight measuring means for measuring the total weight of the replenisher container and the filtrate container, and a total of two containers measured by the weight measuring means. The difference between the two values becomes zero while comparing the value obtained by subtracting the initial total weight measurement value measured at the start of the blood treatment from the weight measurement value with the water removal target value that increases with the processing time according to the set water removal amount. Or a control device for increasing or decreasing the rotation of the filtrate pump, or a weight measuring means for measuring the total weight of the dialysate container, the replenisher solution container and the filtrate container, and three containers measured by the weight measuring means. Of the total weight of Compare the value obtained by subtracting the measured value of the initial total weight measured at the start of blood treatment from the constant value with the target value of water removal that increases with the processing time according to the set water removal amount, and until the difference between the two becomes zero, the filtrate pump. And a control device for increasing and decreasing the rotation of the blood purification device.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described more specifically, but the present invention is not limited thereto.

FIG. 1 shows an example of continuous slow hemodiafiltration which is one embodiment of the apparatus of the present invention, and FIG. 2 shows an example of continuous slow hemodialysis.
FIG. 3 shows an example of continuous slow hemofiltration, FIG. 4 shows an experimental example of continuous slow hemofiltration, and FIG.

Example 1 In FIG. 1, a blood introduction tube 1 is set on a blood pump 2 on the way, and then connected to an inlet of a diafiltration filter 3. A blood outlet pipe 4 is connected to an outlet of the diafiltration filter 3, and a blood circulation circuit is formed by the blood inlet pipe 1 to the blood outlet pipe 4.
The diafiltration filter 3 has a built-in hollow fiber or flat membrane diafiltration membrane. This filtration membrane has a pore size of 40
In general, a homogeneous microporous membrane or a microfiltration membrane or a so-called asymmetric membrane composed of a porous support layer and a microporous structure layer can be preferably used. Examples of such a membrane include a homogeneous microporous membrane and an asymmetric structure membrane made of a cellulose derivative such as cellulose acetate, polyolefin, polyacrylonitrile, polyamide, polyester, polysulfone, etc. in addition to an ethylene vinyl alcohol (EVA) copolymer. Is used. Among these, it is desirable to use a membrane such as an EVA-based material having excellent biocompatibility, a cellulose derivative, a PMMA film, and a polysulfone. The dialysis filter 3 is provided with a dialysate inlet 5 and a used dialysate outlet 6.
Is connected to a filtrate pump 9, and the filtrate discharge path 8 is attached to a filtrate container 10. A dialysate supply path 13 is connected to the dialysate container 12. The dialysate supply path 13 is connected to the dialysate inlet 5 of the diafiltration filter 3 after the dialysate pump 11 is set on the way. A heater or the like is attached to the dialysate supply path 13. On the other hand, a replenishing solution supply path 16 is connected to the replenishing solution container 15, and the replenishing solution supply path 16 is connected to the middle of the blood outlet tube 4 after the replenishing solution pump 14 is set on the way. The replenisher supply path 16 is provided with a heater and the like. The flow rate of the filtrate pump 9 is an addition flow rate of the flow rate of the dialysate pump 11, the flow rate of the replenisher pump 14, and the dewatering flow rate set by the dewatering setter 22, and the inflow and outflow of the liquid are balanced. The dialysate container 12 and the replenisher container 15 are attached to the same dialysis / replenisher weighing scale 17, and the filtrate container 10 is attached to a filtrate weighing scale 18. According to the value obtained by subtracting the initial total weight measurement value at the start of blood treatment from the total weight value of the dialysis / replenisher weight 19 and the filtrate weight 20 measured by the weighing scale, and the water removal amount set by the water removal setter 22. A signal for increasing or decreasing the flow rate of the filtrate pump 9 is transmitted from the control circuit 21 until the difference between the two becomes zero while comparing with the water removal target value that increases in proportion to the processing time, and the flow rate of the filtrate pump 9 is reduced. Adjust and perform the water removal control of continuous slow hemofiltration dialysis reliably and accurately.

Example 2 In FIG. 2, the blood introduction tube 1 is set on the blood pump 2 on the way, and then connected to the inlet of the diafiltration filter 3. A blood outlet pipe 4 is connected to an outlet of the diafiltration filter 3, and a blood circulation circuit is formed by the blood inlet pipe 1 to the blood outlet pipe 4.
The dialysis filter 3 is provided with a dialysate inlet 5 and a used dialysate outlet 6, and the used dialysate outlet 6 is connected to a filtrate outlet 8, and the filtrate outlet 8 is connected to a filtrate pump 9 on the way. After being set, it is attached to the filtrate container 10. Further, the dialysate supply path 13 is connected to the dialysate container 12, and the dialysate supply path 13 is set after the dialysate pump 11 is set on the way.
It is connected to the dialysate inlet 5 of the diafiltration filter 3. A heater or the like is attached to the dialysate supply path 13. The flow rate of the filtrate pump 9 is an addition flow rate of the flow rate of the dialysate pump 11 and the flow rate of water removal set by the water removal setter 22 to balance the flow of the liquid. On the other hand, the dialysate container 12 is attached to a dialysis / replenisher weight meter 17, and the filtrate container 10 is attached to a filtrate weight meter 18. According to the value obtained by subtracting the initial total weight measurement value at the start of blood treatment from the total weight value of the dialysis / replenisher weight 19 and the filtrate weight 20 measured by the weighing scale, and the water removal amount set by the water removal setter 22. A signal for increasing or decreasing the flow rate of the filtrate pump 9 is transmitted from the control circuit 21 until the difference between the two becomes zero while comparing with the water removal target value that increases in proportion to the processing time, and the flow rate of the filtrate pump 9 is reduced. Adjust the water removal control of continuous slow hemodialysis reliably and with high accuracy.

Example 3 In FIG. 3, the blood introduction tube 1 is set on the way to the blood pump 2 and then connected to the inlet of the diafiltration filter 3. A blood outlet pipe 4 is connected to an outlet of the diafiltration filter 3, and a blood circulation circuit is formed by the blood inlet pipe 1 to the blood outlet pipe 4.
The diafiltration filter 3 is provided with a filtrate outlet 7, and a filtrate outlet 8 is connected to the filtrate outlet 7, and the filtrate outlet 8 is set on a filtrate pump 9 on the way, and then mounted on a filtrate container 10. ing. In addition, the replenisher supply path 1 is
6 is connected, and the replenisher supply path 16 is connected to the replenisher pump 1 on the way.
After being set, it is connected in the middle of the blood outlet tube 4. The replenisher supply path 16 is provided with a heater and the like. The flow rate of the filtrate pump 9 is an addition flow rate of the flow rate of the replenisher pump 14 and the water removal flow rate set by the water removal setter 22 to balance the inflow and outflow of the liquid. On the other hand, the replenisher container 15 is attached to a dialysis / replenisher weighing scale 17, and the filtrate container 10 is attached to a filtrate weighing device 18. According to the value obtained by subtracting the initial total weight measurement value at the start of blood treatment from the total weight value of the dialysis / replenisher weight 19 and the filtrate weight 20 measured by the weighing scale, and the water removal amount set by the water removal setter 22. A signal for increasing or decreasing the flow rate of the filtrate pump 9 is transmitted from the control circuit 21 until the difference between the two becomes zero while comparing with the water removal target value that increases in proportion to the processing time, and the flow rate of the filtrate pump 9 is reduced. Adjust and perform water removal control of continuous slow blood filtration reliably and with high accuracy.

Example 4 For a water model using a water tank 23 instead of a human body, FIG. 4 shows a flow rate of a blood horn of 100 mL / min, a flow rate of a replenisher pump of 10 mL / min, and a water removal treatment setting of 600 mL / hour.
When the continuous slow filtration was performed for about 12 hours continuously in the blood processing circuit shown in FIG. 1, the expected amount of water removed was 7270 g, whereas the amount of water removed in the filtrate container 10 was calculated by a formula [Current Total weight (dialysis / replenisher weight 19 + filtrate weight 18)-
The total weight at the start of the treatment (dialysis / replenisher weight 19 + filtrate weight 18)] was 7221 g, and the error was -0.674%. On the other hand, for a water model using a conventional blood purification device, a blood pump flow rate of 100 mL /
Minutes, the replenisher pump flow rate was 10 mL / min, and the flow rate of the water removal pump 25 was set at 10 mL / min, and the continuous slow blood filtration was performed for about 12 hours continuously in the blood processing circuit shown in FIG.
While the scheduled water removal amount was 7.23 mL, the actual water removal amount was 7,765 mL, and the difference was +7.2.
4%.

[0012]

As described above, according to the present invention, a. Improvement of water removal control accuracy. b. Simplification of circuit and improvement of operation performance by dedicated pump. c. Improved operability by eliminating actual measurement of water removal. d. Reliable water removal control and improved reliability through continuous control. To achieve a high-performance and highly reliable blood purification apparatus.

[Brief description of the drawings]

FIG. 1 is a flow chart of a continuous slow hemodiafiltration apparatus which is one embodiment of the blood purification apparatus of the present invention.

FIG. 2 is a flowchart of a continuous slow hemodialysis apparatus which is one embodiment of the blood purification apparatus of the present invention.

FIG. 3 is a flow chart of a continuous slow blood filtration apparatus which is one embodiment of the blood purification apparatus of the present invention.

FIG. 4 is a flow chart in which continuous slow hemofiltration is actually performed using a water model using the blood purification apparatus of the present invention.

FIG. 5 is a flow chart in which continuous slow hemofiltration is actually performed using a water model using a conventional blood purification apparatus.

[Explanation of symbols]

 Reference Signs List 1 blood introduction pipe 2 blood pump 3 blood processor 4 blood outlet pipe 5 dialysate inlet 6 dialysate outlet 7 filtrate outlet 8 filtrate discharge path 9 filtrate pump 10 filtrate container 11 dialysate pump 12 dialysate container 13 dialysate supply path 14 Replenisher Pump 15 Replenisher Container 16 Replenisher Supply Line 17 Dialyzer / Replenisher Weight Meter 18 Filtrate Weight Meter 19 Dialysis / Replenisher Weight 20 Filtrate Weight 21 Control Circuit 22 Dewatering Setting Circuit 23 Water Tank 24 Weight Correction Pump 25 Removal Water pump

Claims (1)

[Claims] 1. A blood circulation path for introducing a patient's blood into a blood processor containing a semipermeable membrane and returning the blood to the patient again, a dialysate supply path for supplying a dialysate from the dialysate container to the blood processor. A replenisher supply for replenishing a patient with a replenisher from a replenisher via the blood discharge path for discharging spent dialysate from the blood processor to a filtrate container, or the blood circulation path, and the blood circulation path. And a filtrate discharge path for discharging blood filtrate from the blood processor to a filtrate container, or the blood circulation path,
The replenisher supply path, the dialysate supply path, and a filtrate discharge path for discharging a blood filtrate and a used dialysate from the blood processor to a filtrate container. In the blood purification apparatus to be performed, a weight measuring means for measuring the total weight of the dialysate container and the filtrate container, and an initial value measured at the start of blood processing from the measured value of the total weight of the two containers measured by the weight measuring means. A control device is provided for comparing the numerical value obtained by subtracting the total weight measurement value and the target value of water removal that increases with the treatment time according to the set water removal amount, while increasing or decreasing the rotation of the filtrate pump until the difference between the two becomes zero. did,
Or a weight measuring means for measuring the total weight of the replenisher container and the filtrate container, and an initial total weight measurement value measured at the start of blood treatment from the measurement value of the total weight of the two containers measured by the weight measurement means. A control device for increasing or decreasing the rotation of the filtrate pump until the difference between the reduced value and the target value of water removal that increases with the treatment time according to the set water removal amount increases with the processing time, or the dialysis, or A weight measuring means for measuring the total weight of the liquid container, the replenisher container and the filtrate container, and an initial total weight measurement measured at the start of the blood treatment from the measured values of the total weight of the three containers measured by the weight measuring means A control device for increasing or decreasing the rotation of the filtrate pump until the difference between the reduced value and the target value of water removal that increases with the treatment time according to the set water removal amount is reduced. Feature Liquid purification equipment.