JPH0578347B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an artificial dialysis device, and particularly to a water removal control mechanism for monitoring poor water removal and water removal accuracy in an artificial dialysis device equipped with a water removal control mechanism. This invention relates to a monitoring device.

[Conventional technology]

Today, artificial dialysis machines have come into widespread use as devices for performing dialysis therapy for patients with chronic renal failure. Dialysis therapy is especially effective for patients who cannot produce urine.
The existence of an artificial dialysis machine is extremely important, as it is a necessary means to maintain life by removing water from food and drink (hereinafter referred to as water removal).

Recently, high-performance dialysis machines have been developed, making it possible to remove a large amount of water. However, if the water removal control is incorrect, it may remove more water than necessary or may not remove enough water, which can endanger the patient's life. Therefore, it has become necessary for artificial dialysis equipment to maintain a function that allows proper and safe water removal management.

From this point of view, an equal flow rate circuit for dialysate is constructed using a duplex pump that equalizes the flow rate of dialysate flowing into the dialyzer and the flow rate of dialysate flowing out from the dialyzer. An artificial dialysis machine equipped with a water removal control mechanism has been developed, which includes a water removal pump that can remove an equivalent amount of water from the blood side of the dialyzer when a fixed amount of fluid is removed.

In this type of artificial dialysis machine, when you set an arbitrary amount of water removal, the water removal pump removes the amount of fluid corresponding to the amount of water removed according to this set value, so water removal is caused by variations in the performance of the dialysis machine. Errors can be ignored and accurate water removal can be achieved.
However, even in this type of artificial dialysis machine, when operated for a long time, dust and carbonate precipitates become trapped, causing leakage from the diaphragm of the back pressure valve and abrasion of pump mechanical parts, resulting in accurate water removal control. This may make it difficult to perform water removal, resulting in poor water removal. For this reason, conventional artificial dialysis apparatuses employ a monitoring method that detects phenomena that cause poor water removal based on changes in dialysate pressure.

[Problem to be solved by the invention] When performing dialysis treatment using an artificial dialysis machine equipped with the above-mentioned water removal control mechanism, the rate of dialysate is generally 500ml/min (30ml/hour) due to dialysis efficiency.
Therefore, if dialysis is performed for 5 hours, approximately 150 will be consumed. In this case, although it varies depending on the patient, 1
It is required to control the integrated value of the flow rate difference between the inflow dialysate flow rate and the outflow dialysate flow rate to within ±300 ml while removing approximately 1 to 5 times the amount of water removed in each dialysis. Ru. however,
If you try to measure an error of ±300ml for a total dialysate volume of 150ml, the accuracy will be ±0.2%,
It is difficult to stably measure the inflow dialysate flow rate and the outflow dialysate flow rate to a dialyzer using a conventional flow meter.

In addition, as a result of investigating the main factors that caused poor water removal in the mechanical components of conventional dialysis machines using a water removal control mechanism that uses an equal flow rate circuit using dual pumps, the following findings were found. .

Defective back pressure valve installed on each pump discharge piping side in the dialysate circuit.

Duplex pump failure.

Plumbing leaks.

Malfunction of water removal pump.

It was confirmed that these matters accounted for most of the causes of poor water removal. In addition, in conventional artificial dialysis machines, when adjusting the back pressure of each back pressure valve, the piping is removed, a pressure gauge is connected and placed in the appropriate place, and the back pressure is adjusted while checking the pressure indicated by this pressure gauge. In addition, when investigating the cause of poor water removal, it is necessary to connect and arrange a pressure gauge to check the back pressure. Monitoring for proper water removal control is insufficient, and water removal is insufficient. There is a drawback that control management and maintenance work are extremely complicated.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an artificial dialysis machine having a water removal control mechanism using duplex pumps in the dialysate circuit to form an equal flow rate circuit, in which each back pressure of the duplex pumps and the back pressure of the water removal pump are controlled. Through constant detection, failures in piping parts such as back pressure valves, duplex pumps, water removal pumps, solenoid valves, etc. can be detected during dialysis treatment or other test run conditions, and water removal failures can be monitored easily and reliably. An object of the present invention is to provide a monitoring device for a water removal control mechanism in an artificial dialysis machine.

[Means for Solving the Problems] A monitoring system for a water removal control mechanism in an artificial dialysis apparatus according to the present invention provides a monitoring system for a dialysate supply system and a dialysate drainage system connected to the dialysate side of a dialyzer. Duplex pumps are connected to form an equal flow rate circuit, a back pressure valve is provided on the discharge side of each of the duplex pumps, and a circulation pump is provided between the dialyzer and the duplex pump in the dialysate drainage system. In an artificial dialysis machine equipped with a water removal control mechanism in which a water removal system equipped with a water removal pump and a back pressure valve is branched out from the downstream side of the pump, a dialysate supply system and a dialysate drainage system are installed in close proximity to the dialyzer. A three-way electromagnetic switching valve is provided in each system, a bypass pipe is connected between these two switching valves, a dialysate pressure sensor is provided downstream of the bypass pipe of the dialysate drainage system, and a dialysate pressure sensor is provided downstream of the bypass pipe of the dialysate drainage system. It is characterized in that a pressure sensor for measuring back pressure is provided on the upstream side of each back pressure valve provided on each discharge side of the water pump.

In the above-mentioned monitoring device, the duplex pump, circulation pump, and water removal pump are each driven with the bypass pipes connected to each other by the three-way electromagnetic switching valve, and the pressure change in the equal flow rate circuit within a predetermined time is detected as the dialysate pressure. The sensor may measure the pressure, and when the obtained pressure measurement value reaches a reference value, the operation of the water removal pump or the duplex pump and normal conditions such as piping leakage can be determined. In this case, in a state where the dialysate pressure has a required pressure difference with respect to atmospheric pressure in the equal flow rate circuit, all duplex pumps, circulation pumps, and water removal pumps are stopped, and within the equal flow rate circuit within a predetermined time. The dialysate pressure sensor may measure a change in the pressure of the dialysate, and if the obtained pressure measurement value changes in the direction of atmospheric pressure, a pipe leakage state can be determined. Similarly, in a state where the dialysate pressure has a required pressure difference with respect to atmospheric pressure in the equal flow rate circuit, the duplex pump, circulation pump, and water removal pump are all stopped, and each of the duplex pump and water removal pump is It is also possible to perform pressure measurement with a pressure sensor for measuring back pressure provided on the discharge side, and to determine whether the back pressure valve is defective when the obtained pressure measurement value is other than a reference value.

Furthermore, in the above-mentioned monitoring device, the duplex pump and the circulation pump are driven with the bypass pipe connected to each other by the three-way electromagnetic switching valve, and the pressure change in the equal flow rate circuit is measured by the dialysate pressure sensor within a predetermined period of time. However, when the obtained pressure measurement value exceeds a reference value, it can be configured to determine whether a duplex pump has failed or a water removal error has occurred.

[Effect]

According to the monitoring device for the water removal control mechanism in an artificial dialysis apparatus according to the present invention, three-way electromagnetic switching valves are provided in the dialysate supply system and the dialysate drainage system in close proximity to the dialyzer, respectively. A bypass pipe is connected between them, and a water removal system equipped with a water removal pump is branch-connected to an equal flow rate circuit composed of a duplex pump and a circulation pump, and a back pressure valve is installed on the discharge side of the duplex pump and water removal pump, respectively. At the same time, a back pressure side regular pressure sensor is provided on the upstream side thereof, and a dialysate pressure sensor is further provided on the downstream side of the bypass pipe of the dialysate drainage system, so that the bypass pipe is in communication with the duplex pump. Water removal control can be performed by simultaneously driving, stopping, or selectively driving the circulation pump and the water removal pump, measuring the pressure using each of the pressure sensors, and comparing the obtained pressure measurement value with a preset reference value. It is possible to determine whether the involved duplex pumps, circulation pumps, water removal pumps, various solenoid valves, back pressure valves, etc. are normal or in failure, and easily and quickly predict the occurrence of water removal errors or water removal failures in advance. be able to.

〔Example〕

Next, an embodiment of a monitoring device for a water removal control mechanism in an artificial dialysis apparatus according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a system diagram showing an example of the configuration of an artificial dialysis apparatus implementing a monitoring device for a water removal control mechanism of the present invention. In FIG. 1, reference numeral 10 indicates a dialyzer, and on the dialysate side of the dialyzer 10, there is a dialysate supply system 14 and a dialysate drainage system 16 that constitute an equal flow rate circuit via a duplex pump 12. are connected. In this case, the duplex pump 12 is constituted by a reciprocating pump having a single plunger and two pump parts 18a and 18b having the same volume and performing suction and discharge operations alternately. In addition, three-way electromagnetic switching valves 20 and 22 are provided in the dialysate supply system 14 and dialysate drainage system 16, respectively, in close proximity to the dialyzer 10, and between these two three-way electromagnetic switching valves 20 and 22, the dialyzer 1 A bypass pipe 24 for short-circuiting is connected and arranged. The dialysate drainage system 16 includes a three-way electromagnetic switching valve 22 and a dual pump 1.
A circulation pump 26 is provided between the circulation pump 2 and the circulation pump 26, and a water removal system 32 including a water removal pump 30 is connected downstream of the circulation pump 26 via a degassing chamber 28. In this case, the water removal pump 30 is also configured as a reciprocating pump. Therefore, the duplex pump 12 and water removal pump 30 configured as reciprocating pumps in this way
By providing back pressure valves 34, 36, and 38 on the discharge side and setting to maintain a predetermined back pressure, the discharge flow rate of each pump can be maintained constant. Note that the circulation pump 26 is provided with a back pressure valve 40 in parallel thereto. Also, dialyzer 1
A blood system 44 connected to the patient K is connected to the blood side of the patient K via a blood pump 42 as appropriate.

The above configuration shows the basic configuration of an artificial dialysis apparatus equipped with a water removal control mechanism using a typical dual pump.

However, in the artificial dialysis apparatus of this embodiment, the back pressure valve 34 on the fluid supply side and the back pressure valve on the drainage side disposed on each discharge side of the duplex pump 12 provided in the dialysate supply system 14 and the dialysate drainage system 16 are 36, pressure sensors 46 and 48 for measuring back pressure are attached, respectively. In addition, the water removal pump 3 provided in the water removal system 32
A pressure sensor 50 for measuring back pressure is attached to the back pressure valve 38 disposed on the discharge side of the pump. Further, on the upstream side of the circulation pump 26 provided in the dialysate drainage system 16, there is a dialysate pressure sensor 52 for measuring dialysate pressure.
Attached. A deaeration pipe 56 is led out from the deaeration chamber 28 via an electromagnetic on-off valve 54, and this deaeration pipe 56 is connected to the dialysate drainage system 16 downstream of the duplex pump 12.

Next, the monitoring function and operation of the artificial dialysis apparatus of this embodiment configured as described above will be explained.

First, during dialysis treatment, the dialysate supply system 14
The three-way electromagnetic switching valves 20 and 22 are switched so that the dialysate drainage system 16 and the dialysate drain system 16 communicate with the dialyzer 10, and the duplex pump 12, circulation pump 26, and water removal pump 3
0 respectively. Furthermore, the blood pump 42 is driven to supply the patient K's blood to the dialyzer 10. However, the pump section 18 of the duplex pump 12
The dialysate discharged from the liquid supply side back pressure valve 34,
It is introduced into the dialyzer 10 via the three-way electromagnetic switching valve 20, and undergoes dialysis with blood via the dialysis membrane. In this way, the dialysate treated with dialysis is
Three-way electromagnetic switching valve 22, circulation pump 26, pump section 18b of duplex pump 12, and drain side back pressure valve 36
is discharged through. In this case, the flow rate of the dialysate in the dialysate supply system 14 and the flow rate in the dialysate drainage system 16 are equal, and the dialysate systems constitute an equal flow rate circuit. Therefore, if the water removal pump 30 is driven and a predetermined amount of water is removed from the dialysate drainage system 16 constituting the equal flow rate circuit through the water removal system 32, the dialyzer 1
The same amount of water as the amount of water removed can be removed from the blood side to the dialysate side through the 0 dialysis membrane.

The above shows the basic dialysis operation of the artificial dialysis apparatus of this embodiment, and in the present invention,
The artificial dialysis apparatus having the above configuration can exhibit a self-diagnosis function for detecting poor water removal and determining the cause thereof. The outline of the monitoring device for demonstrating this self-diagnosis function is as follows.
Incidentally, FIG. 2 is a time chart and a waveform diagram schematically showing the operating state of the monitoring device, and shows a normal state.

a) Initial Settings The three-way electromagnetic switching valves 20 and 22 are switched so that the bypass pipe 24 is in communication, the duplex pump 12 is driven, and the electromagnetic on-off valve 54 is opened to operate the equal flow rate circuit of the dialysate system and perform degassing. (See Figure 2).

b) Checking the operation of the water removal pump 30 After sufficient deaeration has been performed in the step a), the electromagnetic on-off valve 54 is closed and the water removal pump 30 is driven. In this case, since the dialysate system is not refilled with fluid from the dialyzer 10, a volume change of the dialysate occurs within the closed loop of the dialysate system formed by the duplex pump 12, resulting in pressure A change (increase in negative pressure) occurs, and this state is measured and detected by the dialysate pressure sensor 52. There are two methods for determining normal operation in this case:

If the dialysate pressure reaches a predetermined pressure within a predetermined time, it is determined to be normal.

The dialysate pressure is determined to be normal if a predetermined pressure change occurs in a predetermined time.

Therefore, in this example, by the above method,
Pressure measurement value 1 detected by dialysate pressure sensor 52
However, a predetermined negative pressure (for example -
300 mmHg), and it is determined from this that the water removal pump 30 is operating normally (see Fig. 2). However, water removal pump 3
If the pressure measurement value I detected by the dialysate pressure sensor 52 does not reach a predetermined negative pressure within a reference time from the start of driving at 0, the water removal pump 30
It is determined that the setting is incorrect or there is a failure (see Figure 3).

c) Confirmation of piping leak status in the dialysate system After checking the previous item b), check that the duplex pump 12, circulation pump 26, and The drive of the water removal pump 30 is stopped. At this time, since the electromagnetic on-off valve 54 is closed, the dialysate system is cut off between each pump. Therefore, the change in the pressure measurement value detected by the dialysate pressure sensor 52 is measured from the time when each pump is stopped, and if this pressure measurement value hardly changes over time, it is determined to be in a normal state ( (See Figure 2). However, if the pressure measurement value changes toward the atmosphere over time, it can be determined that there is a leak in the piping, that is, a defect in the various electromagnetic valves (see FIG. 4).

d) Confirming the back pressure of the pressure sensors 46, 48, and 50 for measuring the back pressure When confirming the above item c), at the same time, check the pressure sensors 46, 46, and 50 for measuring the back pressure installed on the liquid supply side, liquid drain side, and water removal side, respectively. 48 and 50 back pressure measurements are taken. In this case, if the back pressure measurement value is maintained at a predetermined pressure after a predetermined period of time has elapsed, it is determined to be normal (see FIG. 2). However, if the measured back pressure value changes to a reference value (for example, 0.6 kg/cm ² ) or less over time, it can be determined that the back pressure valve is defective (see FIG. 4).

e) Check the operation of the duplex pump After completing all the above checks, check the operation of the water removal pump 30.
While driving is stopped, the duplex pump 12 and the circulation pump 26 are driven, and the dialysate pressure sensor 52 detects the balance between the discharge amount on the supply side and the discharge amount on the drain side. In other words, the occurrence of a flow rate difference between the supply side and the drain side (this results in a water removal error) causes a volume change in the equal flow rate circuit, and in this case, the dialysis pressure changes. .
Therefore, the change in dialysate pressure over a predetermined period of time is measured by the dialysate pressure sensor 52, and if this pressure measurement value is within a reference value (for example, 100 mmHg), it is determined to be in a normal state (see Figure 2). . However, if the pressure measurement value becomes a negative pressure exceeding the reference value as a predetermined time elapses, it can be determined that the duplex pump 12 has failed (see FIG. 5).

In addition, the relationship between the above-mentioned flow rate difference between the supply side and the drain side (water removal error) and the amount of pressure change in the dialysate pressure is
As a result of analysis using orthogonal polynomials, the characteristics shown in FIG. 6 were obtained. In Figure 6, the variance ratio F is significant at a significance level of 1%, and the regression line y is y=
The result was 1.642x+5.18, which was confirmed to be extremely significant. Further, in FIG. 6, the standard value of the amount of change in dialysate pressure is based on a water removal error of 30 ml/h, and the upper limit value of 69 for the water removal error of 30 ml/h. Conversely, the reliability limit of the alarm at the upper limit value 69 is 30 to 47 ml/h within the water removal error range.

The self-diagnosis function described above is performed by bypassing the dialyzer 10 and interrupting the dialysis operation, but for example, even during the dialysis operation, each back pressure measurement sensor 46 48 and 50 may be configured to constantly monitor back pressure to detect leaks in each back pressure valve 34, 36, 38.

In addition, regarding each check item as the self-diagnosis function, a microcomputer is used to automatically store the measured value and perform comparison calculations with preset conditions, and if the value is outside the appropriate tolerance range, It is preferable to configure the system to generate an alarm output signal as appropriate. It goes without saying that each of the confirmation items b) to e) of the self-diagnosis function can be implemented by changing the order of the confirmation steps in various ways.

〔Effect of the invention〕

As is clear from the above-mentioned embodiments, according to the present invention, leaks occurring in back pressure valves, piping including various solenoid valves, duplex pumps, water removal pumps, etc., which are the main causes of poor water removal, can be easily confirmed. Moreover, the location of the leakage can be used to immediately locate the location of the defect or failure. Therefore, the monitoring device for the water removal control mechanism that functions in this way detects poor water removal and traces the cause of the problem by making changes to the piping, etc., while the dialysis operation is interrupted before or during the dialysis operation. It can be carried out easily and quickly without any problems, improving the reliability of the water removal control mechanism, and making it possible to predict failures in water removal in advance.This not only improves the safety of dialysis treatment, but also reduces maintenance work. It has many advantages such as ease of use.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various design changes can be made without departing from the spirit of the present invention. .

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing an embodiment of an artificial dialysis machine implementing a monitoring device for a water removal control mechanism according to the present invention, and Figs. 2 to 5 show judgments made by the self-diagnosis function of the monitoring device of the present invention. Each shows the operating characteristics. Figure 2 is an operating characteristic waveform diagram showing the normal state in the entire diagnostic process, Figure 3 is an operating characteristic waveform diagram of the water removal pump, and Figure 4 is a pipe leakage state and back pressure valve. Figure 5 is a waveform diagram showing the back pressure characteristics of the duplex pump, Figure 6 is a waveform diagram of the operating characteristics of the duplex pump, and Figure 6 is the relationship between the flow rate difference between the fluid supply side and the drain side of the duplex pump and the amount of change in dialysate pressure. FIG. 10...Dylyzer, 12...Double pump, 14...
... Dialysate supply system, 16 ... Dialysate drainage system, 18
a, 18b... pump section, 20, 22... three-way electromagnetic switching valve, 24... bypass pipe, 26... circulation pump, 28... deaeration chamber, 30... water removal pump, 32... water removal system, 34, 36, 38... Back pressure valve, 40... Back pressure valve, 42... Blood pump, 44
... Blood system, 46, 48, 50 ... Pressure sensor for back pressure measurement, 52 ... Dialysate pressure sensor, 54 ...
Electromagnetic on-off valve, 56...deaeration pipe, K...patient.

Claims (1)

[Claims] 1. A duplex pump is connected to a dialysate supply system and a dialysate drainage system connected to the dialysate side of a dialyzer to form an equal flow rate circuit, and the discharge side of the duplex pump a back pressure valve is provided in each, and a circulation pump is provided between the dialyzer and the duplex pump in the dialysate drainage system,
Furthermore, in an artificial dialysis machine equipped with a water removal control mechanism in which a water removal system equipped with a water removal pump and a back pressure valve is branched out from the downstream side of the circulation pump, a dialysate supply system and a dialysis system are installed in close proximity to the dialyzer. A three-way electromagnetic switching valve is provided in each of the dialysate drainage systems, a bypass pipe is connected between the two switching valves, a dialysate pressure sensor is provided downstream of the bypass pipe of the dialysate drainage system, and the dual type 1. A monitoring device for a water removal control mechanism in an artificial dialysis machine, characterized in that a pressure sensor for measuring back pressure is provided on the upstream side of a back pressure valve provided on each discharge side of a pump and a water removal pump. 2. With the bypass pipes connected in communication using the three-way electromagnetic switching valve, drive the duplex pump, circulation pump, and water removal pump, respectively, and measure the pressure change in the equal flow rate circuit within a predetermined time using the dialysate pressure sensor, The water removal control mechanism in an artificial dialysis apparatus according to claim 1, wherein the water removal control mechanism in an artificial dialysis apparatus is configured to determine the operation of the water removal pump or the duplex pump and whether there is a leak in the pipes or the like when the obtained pressure measurement value reaches a reference value. monitoring equipment. 3. In a state where the dialysate pressure has a required pressure difference with respect to atmospheric pressure in the equal flow rate circuit, all duplex pumps, circulation pumps, and water removal pumps are stopped, and the pressure in the equal flow rate circuit is adjusted within a predetermined period of time. 3. The water removal control mechanism in an artificial dialysis apparatus according to claim 2, wherein the change is measured by a dialysate pressure sensor, and a pipe leakage state is determined when the obtained pressure measurement value changes in the direction of atmospheric pressure. monitoring equipment. 4 With the required pressure difference between the dialysate pressure and the atmospheric pressure in the equal flow circuit, the duplex pump, circulation pump, and water removal pump are all stopped, and the discharge side of each of the duplex pump and water removal pump is 4. The artificial body according to claim 2 or 3, wherein the pressure is measured by a pressure sensor for measuring back pressure provided in the back pressure valve, and a defect in the back pressure valve is determined when the obtained pressure measurement value is other than a reference value. A monitoring device for the water removal control mechanism in a dialysis machine. 5 With the bypass pipes connected through the three-way electromagnetic switching valve, drive the duplex pump and circulation pump, measure the pressure change in the equal flow rate circuit within a predetermined time using the dialysate pressure sensor, and measure the pressure obtained. 2. A monitoring device for a water removal control mechanism in an artificial dialysis apparatus according to claim 1, wherein the monitoring device is configured to determine whether a duplex pump has failed or a water removal error has occurred when the value exceeds a reference value.