JPH0720492B2 - Blood purification device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION {Industrial field} The present invention provides an over-type blood purification system in which waste products in arterial blood of a patient are put together with water by an organ and a corresponding infusion is supplied into venous blood. More particularly, the present invention relates to a blood purification apparatus that can perform blood purification treatment without being subjected to any special restrictions such as dialysis facilities.

{Prior Art} An over-type blood purification device used for renal failure or the like may be used beside a patient's bed in an ordinary hospital facility.

For this reason, it is necessary to make it compact in terms of space, and it is necessary that it can be easily operated by anyone other than a dialysis specialist.

Generally, as a device for purifying blood while maintaining a balance between the amount of blood taken out of the patient's body and the amount of blood returned to the body, when purifying blood, there is excess liquid discharged from the filter. A weight method in which the weight of the replenisher solution to be supplied to the purified blood is measured, and the weight ratio of the replenisher solution and the solution weight of the measured replenisher solution is set to a constant weight ratio (for example, Japanese Patent Publication 55
(See Japanese Laid-Open Patent Publication No. 13731), and a pump for pumping blood and a pump for sucking liquid by one twin roller pump,
There is known a volumetric system (for example, see JP-A-54-18475) in which the liquid amount and the replenishing amount are made equal to maintain balance and measure the amount of the opening container to which the liquid amount is supplied.

{Problems to be Solved by the Invention} However, the above-mentioned conventional weight system requires a weight measuring device and weight control, and the device becomes large in size and inconvenient to handle.

Further, in the volume method, the discharge flow rate cannot be individually corrected when the two input pressures of the dual roller pump are changed or when the tube diameter is changed, and the flow rate accuracy is deteriorated. Operability is poor because it requires a circuit and is complicated.

The object of the present invention is to easily deal with the problems of large size, flow rate accuracy and operability of the above-mentioned prior art device, even in an ordinary hospital, beside the bed, and can be easily used by doctors other than dialysis specialists. Another object of the present invention is to provide a blood purification device that realizes reduction in size and weight of the device, simplification of operation, and improvement of sufficient safety accuracy such as flow rate accuracy.

{Means for Solving the Problems} The configuration of the present invention that achieves the above object is as follows. That is, an extracorporeal device is provided in the extracorporeal blood circulation circuit, and waste products in the blood are discharged to the outside of the system by a liquid pump through the ultrafiltration membrane in the extracorporeal device. In a blood purification apparatus in which an infusion volume corresponding to the volume is returned to the blood circulation circuit by an infusion pump, a) a fluid pump drive motor for driving the fluid pump, and a rotation speed of the fluid pump drive motor A water removal speed setting device, a rotation speed detection means of the liquid pump drive motor, a liquid pressure detection means provided on the suction side of the liquid pump, and b) an infusion pump drive motor for driving the infusion pump An infusion speed setting device for setting the number of revolutions of the infusion pump driving motor, a number of revolutions detecting means of the infusion pump driving motor, an infusion pressure detecting means provided on the suction side of the infusion pump, and c) the above liquid Turning the pump drive motor A speed set value correction unit of a liquid pump drive motor that corrects a set value of a water removal speed setting device that sets the number of revolutions based on a hydraulic pressure signal from the hydraulic pressure detection means, d) The infusion pump drive motor An infusion pump drive motor speed setting value correction unit that corrects the set value of the infusion speed setting device that sets the number of revolutions of the infusion pump based on the infusion pressure signal from the infusion pressure detection means. The difference between the actual rotation speed of the pump drive motor and the actual rotation speed of the infusion pump drive motor was compared with the water removal speed setting value of the liquid pump drive motor, and this was outside the predetermined allowable range. At this time, an abnormal signal is generated, and f) the actual rotation speed of the infusion pump drive motor is compared with the speed set value of the infusion pump drive motor, and this is outside the predetermined allowable range. The blood purification device is characterized in that it emits an abnormal signal when the blood purification is performed.

Next, the structure and operation of the blood purification apparatus of the present invention will be described based on an embodiment shown in the drawings.

FIG. 1 is a flow chart of the blood purification apparatus according to the present invention.

Blood is taken from the patient's artery 1 and passed through the ultrapermea in the ultrafiltration device 2 to return clean blood to the vein 3 while the liquid 4 passes through the liquid circuit 4a and the liquid drip chamber 5 The liquid rotary pump 7 driven by the pump driving pulse motor 6 discharges the liquid from the liquid circuit 4b.

The infusion solution 8 is delivered through the infusion drip chamber 9 by the infusion rotary pump 11 driven by the infusion pump driving pulse motor 10, and is delivered to the vein 3 together with purified blood.

Of the speed monitoring of the pulse motors 6 and 10 that drive the rotary pumps 7 and 11, first, the liquid pump driving pulse motor 6
Is determined by the set value from the water removal speed setting device 12.

Here, the pressure of the liquid drip chamber 5 is measured by a liquid pressure sensor.
Detected as hydraulic pressure at 13, and based on the change in the value of this hydraulic pressure, the set value from the water removal speed setting device 12 is changed to the speed controller.
After being corrected in 14, a signal is sent to the liquid pump driving pulse motor 6 as a speed set value.

Further, the encoder 15 converts the number of rotations of the liquid pump driving pulse motor 6 into a pulse, and the speed controller 14 feeds back to monitor whether or not it is rotating according to the set value. Then, an abnormal action such as stopping the pulse motor 6 for driving the liquid pump is performed (corresponding to the liquid-infusion balance monitor 212 shown in FIG. 2 described later).

Similarly, the infusion pump driving pulse motor 10 has its rotation speed determined by the set value from the infusion pump speed setting device 16, and determines the pressure of the infusion drip chamber 9 as an infusion pressure sensor.
Detected as the infusion pressure in 17, based on the change in the value of this infusion pressure, the set value from the infusion pump speed setting device 16 is corrected by the speed controller 14, and then to the infusion pump driving pulse motor 10. A signal is sent as a speed setpoint.

The rotation speed of the infusion pump driving pulse motor 10 is converted into a pulse by the encoder 18, and is fed back to the speed controller 14 to monitor whether it is rotating according to the set value. Then, an abnormal action such as stopping the infusion pump driving pulse motor 10 is performed (corresponding to infusion rate monitor 213 shown in FIG. 2 described later).

Abnormality, liquid flow rate, and infusion flow rate are expressed as values proportional to the rotation speed of the pump, but the flow rate of the roller pump is inaccurate as it is depending on the inlet pressure of the pump. In addition to the pump rotation speed, the effects of hydraulic pressure and infusion pressure, which have been experimentally determined in advance, are corrected to obtain an accurate fluid flow rate and infusion flow rate.

An example of using a microprocessor for this speed control and abnormality monitoring is shown in FIG.

The portion surrounded by the broken line in FIG. 2 shows the speed controller 14 shown in FIG.

The signal set by the water removal speed setting device 12 is combined with the infusion speed setting value, and then corrected by the hydraulic pressure correction unit 21 by the hydraulic pressure signal from the hydraulic pressure sensor 13, and the liquid pump speed control unit.
Then, the rotation speed of the liquid pump driving pulse motor 6 is set at 22. The liquid pump 7 is driven according to the rotation of the liquid pump driving pulse motor 6.

Similarly, the signal set by the infusion pump speed setting device 16 is
After being corrected by the infusion pressure correction unit 24 by the infusion pressure signal from the infusion pressure sensor 17 and the set value correction unit 23, the signal is given to the infusion pump speed control unit 25 to rotate the infusion pump driving pulse motor 10. The number is set. The infusion pump 11 is driven according to the rotation of the infusion pump driving pulse motor 10.

Details of the set value correction unit 23 will be described later.

Next, the rotation speed of the liquid pump driving pulse motor 6 is converted into a pulse by the rotation pulse output unit 15 and output. This pulse is corrected by the hydraulic pressure correction unit 26 according to the hydraulic pressure, and a liquid amount count 27 is performed as the liquid amount.

Similarly, the rotation speed of the infusion pump driving pulse motor 10 is
The rotation pulse output unit 18 converts the pulse into a pulse and outputs the pulse.
The pulse is corrected by the transfusion pressure correction unit 28 according to the transfusion pressure, and the transfusion amount counter 29 is operated as the transfusion amount. The count value is used as an infusion volume and displayed on the infusion volume display unit 210. In addition, the value obtained by subtracting the infusion volume count 29 from the fluid volume count 27 is taken as the water removal volume, and the water removal volume display section
Displayed at 211.

Further, in order to check the abnormality of the pump, the rotation pulse output unit 15 according to the rotation of the liquid pump driving pulse motor 6
And the pulse from the rotation pulse output unit 18 according to the rotation of the infusion pump driving pulse motor 10,
The liquid-infusion balance monitoring unit 212 compares the set value of the water removal rate meter 12 with each other to monitor the balance of both pumps. When the balance exceeds the allowable range, an abnormal alarm is output and both pumps are stopped by stopping both pulse motors.

The infusion rate monitoring unit 213 monitors the abnormality of the pump by comparing the pulse from the rotation pulse output 18 corresponding to the infusion pump driving pulse motor 10 with the set value of the infusion pump speed setter 16. If the difference between the pulse and the set value exceeds the allowable range, an alarm will be issued and both pumps will be stopped by stopping both pulse motors.

Next, with respect to the set value correction unit 23, which reduces the liquid amount according to the decrease in the liquid pressure, conventionally, in the blood purification therapy for extracorporeally circulating blood, particularly in the treatment method using the hollow fiber type filter, the filter is used. This is to compensate for the fact that the pores of the polymer membrane that constitutes the above-mentioned structure exhibit a clogging phenomenon over time due to blood proteins and the like.

That is, when the liquid is continued at a certain liquid velocity, the liquid pressure gradually decreases and finally reaches the limit of the membrane pressure resistance strength.

For this reason, usually, the fluid pressure or the extreme overpressure (transmembrane pressure difference) is monitored, and the treatment is performed within the pressure resistance strength.

Since the degree of decrease in the fluid pressure can be reduced by decreasing the fluid velocity, conventionally, the treatment manager decided to perform the treatment to reduce the fluid velocity based on the degree of the decrease in the fluid pressure.

Therefore, by monitoring the decrease in hydraulic pressure and automatically adjusting the liquid speed, it is possible to reduce the decrease in water removal performance due to clogging of the filter, extend the filter life, and reduce the burden on the treatment manager. It is what makes me.

Next, an embodiment incorporating measures against the clogging of the film will be described with reference to FIG.

The pressure of the liquid circuit 4a drawn from the ultrafiltration device 2 is measured by the liquid pressure sensor 13 through the gas phase portion of the liquid drip chamber 5, and the measurement result is input to the speed controller 14.

The speed controller 14 is configured to control the infusion pump 11 and the liquid pump 7 at a speed at which the value set by the infusion speed setting device 16 is corrected by the hydraulic pressure signal of the hydraulic pressure sensor 13.

Here, in the correction by the hydraulic pressure, for example, the change range of the hydraulic pressure is divided into four stages, and the correction coefficient is set for each stage.

That is, for the set value of the infusion pump speed setter 16,
The correction of × 1, × 0.9, × 0.8, × 0.7, etc. is performed by the set value correction unit 23.

In this way, by correcting and controlling the infusion rate and fluid rate in conjunction with the fluid pressure, the life of the ultraperitoneum can be extended, and the infusion rate and fluid rate are automatically corrected, reducing the burden on the treatment manager. it can.

The above will be described using reference numerals.

When the water removal rate is A and the infusion rate is B, for the infusion rate B, the set value correction unit 23 sets a hydraulic pressure sensor for the set value.
Apply the pressure correction a from 13 and use B.a as the infusion pressure correction unit.
Infusion pressure sensor for the discharge flow rate of one revolution of the infusion pump at 24
The pressure correction b from 17 is applied, B · ab enters the infusion pump speed control unit 25, and the pulse motor is driven.

On the other hand, with respect to the water removal speed A, the hydraulic pressure correction unit 21 adds B · a of the set value correction unit 23 to the water removal speed A so that the hydraulic pressure sensor 13 detects the discharge flow rate per revolution of the pump. Apply pressure correction C. That is, it becomes (A + B · a) C, which enters the liquid pump speed control unit 22 to drive the liquid pump driving pulse motor 6.

Output B / ab from the rotation pulse output unit 18 is added to the infusion pressure correction unit.
By 28, 1 / b is multiplied and B · a is integrated by the infusion amount count 29 and displayed on the infusion amount display unit 210.

Similarly, the output from the rotation pulse output unit 15 (A + B · a)
・ C is multiplied by 1 / C by the hydraulic pressure correction unit 26, and A + B ・
a is integrated by the liquid volume count 27, and the infusion volume is subtracted from the fluid volume, that is, (A + B · a) −B
・ A = A is displayed on the water removal amount display section 211.

The infusion rate monitoring unit 213 compares and monitors the set value B from the infusion pump speed setting unit 16 and the output B · ab from the rotation pulse output unit 18 excluding the correction amount ab.

Similarly, in the liquid-infusion balance monitoring unit 212, the rotation pulse output unit 18 uses the set value A from the water removal speed setting unit 12 and the value A + B · a obtained by removing the correction component C from the rotation pulse output unit 15.
It is compared with the value A obtained by subtracting the value B · a · from which the correction amount b is removed.

In this embodiment, a pulse motor is used as the drive source of the pump, but a DC motor, speed control motor or the like may be used as long as the rotation speed can be set.

The pump is not limited to the roller pump used in this embodiment, and may be any other pump as long as it has a quantitative property. However, in the case of the roller pump, the portion where blood and the like flow can be made disposable only by the tube, and the circuit can be easily set. Therefore, the roller pump is preferable.

In this embodiment, the input pressure of the infusion pump is monitored, and the correction is performed corresponding to each pressure. However, since the infusion bottle is placed at a position of approximately constant height, the input pressure becomes constant. Therefore, the correction coefficient may be a constant.

In addition, in the present embodiment, regarding the speed monitoring portion,
Although the speed monitoring is performed using the speed value excluding the pressure correction, the speed monitoring may be performed using the speed value subjected to the pressure correction.

[Brief description of drawings]

FIG. 1 is a flow chart of the blood purification apparatus according to the present invention. FIG. 2 shows another embodiment of the blood purification apparatus according to the present invention, which is a drive control system for an infusion solution pump using a microprocessor, and is shown in a block diagram of the inside of the microprocessor and its peripheral portion. is there. Explanation of symbols in the drawing 1: Artery 2: Ultrafiltration device 3: Vein 4: Liquid 4a, 4b: Liquid circuit 5: Drip chamber for liquid 6: Pulse motor for driving liquid pump 7: Liquid pump 8: Infusion 9: Infusion drip chamber 10: Infusion pump driving pulse motor 11: Infusion pump 12: Water removal speed setting device 13: Fluid pressure sensor 14: Speed controller 15: Rotation pulse output unit (encoder) 16: Infusion pump speed setting device 17 : Infusion pressure sensor 18: Rotation pulse output unit (encoder) 21: Fluid pressure correction unit 22: Fluid pump speed control unit 23: Set value correction unit (counter pressure) 24: Infusion pressure correction unit 25: Infusion pump speed control unit 26 : Fluid pressure compensator 27: Fluid volume compensator 28: Infusion fluid compensator 29: Infusion volume counter 210: Infusion volume indicator 211: Dewatering volume indicator 212: Fluid-infusion balance monitor 213: Infusion velocity monitor

Claims (1)

[Claims] 1. An extracorporeal device is provided in the extracorporeal blood circulation circuit,
Waste products in the blood are discharged to the outside of the system by a liquid pump through the ultrapermeaton inside the ultrafiltration device, and an infusion amount corresponding to the discharged liquid amount is in the blood circulation circuit by the infusion pump. In a blood purification device adapted to return liquid to a), a) a liquid pump drive motor for driving the liquid pump, a water removal speed setting device for setting the number of rotations of the liquid pump drive motor, and the liquid pump drive motor Rotation speed detection means, liquid detection means provided on the suction side of the liquid pump, and b) infusion pump drive motor for driving the infusion pump, and infusion speed setting for setting the rotation speed of the infusion pump drive motor. And a rotation speed detecting means for the infusion pump driving motor, an infusion pressure detecting means provided on the suction side of the infusion pump, and c) a drainage speed setting device for setting the rotation speed of the liquid pump driving motor. Set value to the above hydraulic pressure Compensation unit for correcting the speed set value of the liquid pump drive motor based on the hydraulic pressure signal from the knowing means, d) The set value of the infusion speed setter for setting the rotation speed of the infusion pump drive motor, An infusion pump drive motor speed setting value correction unit for making corrections based on an infusion pressure signal from the detection means, and (e) an actual rotation speed of the liquid pump drive motor and an actual rotation speed of the infusion pump drive motor. And the water removal speed setting value of the liquid pump drive motor are compared, and an abnormal signal is generated when the water removal speed set value of the liquid pump drive motor is out of a predetermined allowable range. It is characterized in that the actual rotation speed of the motor for infusion is compared with the speed set value of the motor for driving the infusion pump, and an abnormal signal is issued when the speed is out of a predetermined allowable range. Purifying apparatus of the liquid.