JP2548483Y2 - Hemodialysis machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a hemodialysis apparatus using a hemodialysis technique such as a so-called artificial kidney.

[Prior Art] A conventional dialysis apparatus will be described with reference to FIG.

FIG. 7 is an example of a monitoring device for dialysis. The dialysate is supplied from the liquid supply line 1, passes through the liquid supply solenoid valve 2, is heated to a predetermined temperature by the heater 4 and the thermistor 5 in the heating tank 3, and passes through the flow meter 6 and the monitor thermistor 7. Dialyzer 21 via dialysate pump 8 and liquid stop solenoid valve 11
Supplied to The dialysate flowing out of the dialyzer 21 passes through a liquid stop solenoid valve 13, a dialysate pressure sensor 14, and a dialysate pump 9, and is drained from a drain line 20. The blood of the patient is supplied to the dialyzer 21 through the arterial circuit drip chamber 24 by the blood pump 22, and the blood from which waste and the like have been removed by the dialyzer 21 passes through the venous drip chamber 26, through the clamper 27, and further through the bubble detector. Returned to patient through 28. Blood pump 22
A syringe pump 23 is connected to an inlet of the vein, and a venous pressure sensor 25 is connected to a venous drip chamber 26. The bypass solenoid valve 12 is branched and connected to the inlet of the liquid stop solenoid valve 11 and the outlet of the liquid stop solenoid valve 13, and when the dialysate temperature is abnormal, the bypass solenoid valve 12 is opened. At the same time, the liquid stopping solenoid valves 11 and 13 are closed.

The dialysate pumps 8 and 9 are controlled so that the flow rates are equal. On the other hand, the dialysate corresponding to the ultrafiltrate in the dialyzer 21 is supplied from the outlet of the liquid stop solenoid valve 11 to the water removal pump 10.
Is sucked at a flow rate equal to the set water removal rate, and introduced into the ultrafiltration amount measuring tank 15. In the ultrafiltration amount measuring tank 15, the filtration rate is determined by dividing the volume from the lower limit level to the upper limit level by the arrival time, and the integrated amount of the filtrate is the time required for draining immediately after reaching the upper limit level. This is done by correcting the minute and multiplying by the number of measurements. Float switches 16 and 17 are used to detect the upper and lower limit levels.
In the measurement mode, the drainage electromagnetic valve 18 is closed, and when the liquid level in the ultrafiltration amount measurement tank 15 rises and the upper limit float switch 16 is turned on, the drainage electromagnetic valve 18 is opened, The liquid in the ultrafiltration amount measuring tank 15 is returned to the inlet of the dialysate pump 8 through the check valve 19. The check valve 19 is for preventing the liquid from flowing backward and flowing into the ultrafiltration amount measuring tank 15. Control of these pumps is performed by the control unit 30.
The operation is performed by the pump driver unit 41 controlling the water removal pump 10 at a rotation speed corresponding to the value set by the ultrafiltration amount setting unit 40. The signals from the upper and lower limit float switches 16 and 17 of the ultrafiltration amount measurement tank 15 are transmitted to the I / O unit 3 in the same control unit 30.
Ingested via 5.

The above is the operation in the dialysis mode.In the disinfection and cleaning modes, hypochlorous acid is supplied as a disinfectant instead of the dialysate, and finally water is supplied to clean the equipment piping. It is supposed to be.

“Problem to be solved by the invention” In the conventional dialysis device, the effective volume (the volume between the upper limit level and the lower limit level) of the ultrafiltration amount measurement tank is 50 to 10
It is about 0ml. On the other hand, the set ultrafiltration volume, especially with the advent of a dialyser with a high water removal membrane, has recently expanded the upper limit of the setting range.
High water removal setting is performed. Where the effective volume is 10
Considering the time required for one measurement (time to reach the effective volume) with 0 ml, if the set water removal rate is 3 l / hr,
While the required time is 2 minutes, the set water removal rate is 0.2 l / hr
In the case of low water removal, it takes 30 minutes to complete. This means that if you change the setting of the water removal rate, the actual water removal rate after the change will not be known until about 30 minutes, not only will the response be slow, but also check the patient's hemodynamics and However, it is inconvenient to check the performance of the water removal pump. In other words, even if the water removal pump is about to break down, it can only be grasped within 30 minutes at worst, which is a serious problem as a treatment device that saves life. However, conventional devices have hardly taken measures against this point.

On the other hand, in the past, the composition of the dialysate was uniform, and acetic acid dialysis was mostly used. However, with the diversification of cases of dialysis patients and the improvement of dialysis performance of dialyzer, in addition to acetic acid dialysis, sodium bicarbonate dialysis and high sodium dialysis are performed. In particular, baking soda dialysis has come to be frequently used for acetic acid intolerance patients and accidental cases such as acetic acid asthma. Although sodium bicarbonate dialysis has many clinical advantages, adhesion of calcium carbonate to piping during disinfection and cleaning is a major problem. This phenomenon occurs in a pipe portion where the flow velocity cannot be increased, and is particularly remarkable in a tank such as the ultrafiltration amount measurement tank 15 which is open to the atmosphere. The removal of calcium carbonate is performed by supplying acetic acid as an acid washing solution.However, in the conventional dialysis device, a method for completely preventing calcium carbonate from adhering to the ultrafiltration amount measurement tank is not considered. Was. That is, in the ultrafiltration amount measurement tank 15,
Since the upper limit level of the dialysate was equal to the upper limit level of the acid washing solution, it was not possible to remove calcium carbonate adhering to the tank wall at the same level. In order to remove this calcium carbonate, it is necessary to further raise the liquid level upper limit level of the acid washing solution to be higher than the liquid level upper level level of the dialysate, and for this purpose, a float switch must be added, Not only does the price rise, but once the float switch is installed, the detection level is fixed, and when the level is changed, the mounting position must be changed each time, which requires a lot of adjustment.

"Means for solving the problem" In the present invention, a liquid level detection means for detecting the liquid level of the ultrafiltration amount measuring tank in multiple stages, and the ultrafiltration amount from the supply port of the dialyzer. Means for setting the ultrafiltration flow rate of the dialysate supplied to the measuring tank and controlling the flow rate to be maintained, flow rate of the dialysate supplied to the supply port side of the dialyzer, and drainage of the dialyzer A means for equalizing the flow rate of the dialysate discharged from the mouth, and a correspondence table between the set ultrafiltration flow rate and the liquid level upper limit level corresponding to a higher liquid level upper level as the set ultrafiltration flow rate is larger. A washing memory comprising: a stored memory; and a means for reading a liquid level upper limit level from the memory according to the set ultrafiltration flow rate value in the dialysis mode, and setting the same in the ultrafiltration amount measurement tank. , Distinguish between disinfectant, acid wash and water The upper limit level of each liquid level in the ultrafiltration amount measuring tank is set according to the type of the liquid and the type of the liquid determined as described above. Means for setting the positional relationship of the tank, and means for controlling the liquid level of the ultrafiltration amount measurement tank to be equal to or less than the upper limit level set in accordance with the liquid, with reference to the liquid level detecting means. Have.

FIG. 1 is a block diagram showing an embodiment of the hemodialysis apparatus of the present invention.

The same parts as those in FIG. 7 are denoted by the same reference numerals, and redundant description will be avoided. In FIG. 1, instead of the float switch in the conventional example, the ultrafiltration amount measuring tank 15 is used as a liquid level detection,
Float 50, shielding cylinder 51 immediately above, and photo sensor 52
Is provided. Second
The figure shows the liquid level detecting means 53 in more detail. In FIG. 2, an axis is set up at an axial center position of the upper surface of the float 50, and four flags A to D having an angular interval of 90 degrees are attached to the axis. The flags A to D are inserted into a shielding cylinder 51 that shields the flags from disturbance light, and four photo sensors 52A to 52D corresponding to the flags A to D are attached to the shielding cylinder 51 at 90-degree intervals. . Each of the flags A, B, C, and D has a pattern in which a transparent portion and a black portion are alternately repeated in the vertical direction to form a pattern (transparent = 1, black = 0). As shown in FIG. 2 (C), the flag A pattern is the finest, the flag D pattern is the coarsest, and the vertical length of the flag B pattern is the flag A.
The vertical length of the pattern of flag C is twice that of flag A
The length of the flag D pattern in the vertical direction is four times that of
8 times that of Meanwhile, photo sensors 52A to 52D
Are generally called photointerrupters, each of which is a pair of an infrared light emitting diode and a phototransistor that receives the infrared light, held on both legs of a U-shaped support, and a photosensor. As shown in FIG. 2B, flags AB are arranged between the infrared light emitting diodes 52A to 52D and the phototransistors, respectively.

When the liquid level reaches the highest level, the lower ends of the flags A to D are located at the photo sensors 52A to 52D, and the respective outputs of the photo sensors 52A to 52D become 1, and when the liquid level becomes the lowest level, Flag A ~
The upper end of D is located at the photo sensors 52A to 52D, the respective outputs of the photo sensors 52A to 52D become 0, the liquid level is intermediate between these, and the photo sensors 52A to 52D have various values,
The level of the liquid level can be known from the state of each output of the photo sensors 52A to 52D. In this embodiment, the minimum vertical length of the flag A pattern is 5 mm. Therefore, the liquid level of the ultrafiltration amount measuring tank 15 is set in the range of the maximum-minimum liquid level difference of 5 × 16 = 80 mm. In this invention, the upper limit level of the dialysis solution <the upper limit level of the disinfecting solution (acid washing solution) <the upper limit level of the washing water. For example, when the dialysate liquid level upper limit level is A = 0, B =
1, C = 0, D = 1, disinfectant (acid cleaning liquid) liquid level upper limit level, A = 0, B = 0, C = 1, D = 1, cleaning water liquid upper limit level, A = 1, B = 1, C = 1, and D = 1 are set.

In FIG. 1, electrodes for distinguishing a dialysate, a disinfectant, an acid wash, and water are provided in the heating tank 3. The most reliable method is to measure the pH and conductivity of the liquid supplied from the liquid supply line 1 by the pH electrode 54 and the conductivity electrode 55. The pH of the dialysate and water is in the range of 6.8 to 7.4, and the pH of hypochlorous acid solution used as a disinfectant is
The pH is in the range of 10 to 12, and the pH of the acetic acid solution used as the pickling solution is in the range of 3 to 5. Therefore, in the measurement of pH, it becomes possible except for the distinction between dialysate and water. Dialysate and water are distinguished by the measured conductivity. The conductivity of the water is almost zero, but the dialysate is about 12.5 mS. Therefore, the types of these four liquids can be determined by a combination of the measurement of pH and the measurement of conductivity.

FIG. 3 is a block diagram showing a main part of this embodiment.
A microcomputer is used for the control unit 30, and a central processing unit (CPU) 31 performs control by sequentially decoding and executing programs stored in a read-only memory (ROM) 32. ROM3
2 stores a control program for the entire dialysis monitoring device, which sets the ultrafiltration amount, measures the ultrafiltration amount in the ultrafiltration amount measurement tank 15 in the dialysis mode, and sets the ultrafiltration amount. Setting of the upper limit level of the filtrate in the ultrafiltration amount measuring tank 15 corresponding to
By taking in the output of the hydrogen ion concentration measurement circuit 38 connected to the hydrogen ion concentration measurement electrode 54 and the output of the conductivity measurement circuit 39 connected to the conductivity electrode 55, determining the supply liquid, and determining the sequence for the determined liquid. A program for setting the liquid level upper limit level of the ultrafiltration amount measuring tank 15 is also included therein. Also included are programs for setting sequences such as preparation, dialysis, blood return, disinfection, and cleaning. The drive circuit 36 drives the drainage electromagnetic valve 18.

The pH of the liquid in the heating tank 3 is measured by the hydrogen ion concentration measuring electrode 54 via the hydrogen ion concentration measuring circuit 38, and the conductivity is measured by the conductivity measuring electrode 55 via the conductivity measuring circuit 39. You. Since the specific method of measurement using these electrodes is known, the description is omitted here.

Each of the signals measured and adjusted to a post-processable signal level is converted into a digital signal by the A / D converter 37 and stored in the RAM 33.

FIG. 4 is a flowchart showing a routine for reading the set ultrafiltration flow rate in the dialysis mode and setting the filtrate upper limit level of the ultrafiltration amount measuring tank 15 corresponding to the read set ultrafiltration flow rate. In this flowchart
First, the CPU 31 reads the set ultrafiltration flow rate in step 1. Next, the CPU 31 stores the pattern (code) of the filtrate upper limit level corresponding to the set value read in step 2 in ROM3.
Read from 2. The figure also shows the correspondence table. For example, when the set ultrafiltration flow rate is 0.721 / hr, the upper limit levels are set to A = 0, B = 1, C = 0, and D = 0. next
The CPU 31 starts measuring the amount of ultrafiltration in step 3, operates the water removal pump 10 via the pump driver 41, and closes the drain electromagnetic valve 18.

Step 4 is a measurement mode, in which the CPU 31 reads the level signal pattern (code) from the liquid level detecting means 53 via the sensor signal processing circuit 40. Next, in step 5, the current level pattern (sensor signal) is compared with the set upper limit level pattern read in step 2 earlier. If the read current level pattern does not reach the set upper limit level pattern, this routine is terminated.
If it matches (or exceeds) the set upper limit level pattern, in step 6 the drain electromagnetic valve 18 is opened. Since the outline of the measurement has been described above, it is omitted here.

During dialysis, this routine is constantly repeated to measure the ultrafiltration volume. That is, ΔS (cross-sectional area of the measuring tank 15)
× Set upper limit level + (Amount of liquid entering the measuring tank while discharging liquid from the measuring tank 15)｝ × η (Number of times the drain electromagnetic valve 18 is opened) to obtain the amount of ultrafiltration The ultrafiltration flow rate is determined by dividing S × the upper limit level by the time from when the liquid solenoid valve 18 is closed to when the upper limit level is reached. If the setting of the ultrafiltration flow rate has been changed, a new set value is read in step 1 of the present routine, and in the next step 2, the filtrate level upper limit is set accordingly. In the conventional example, the effective volume of the measuring tank 15 was 100 ml, and when the setting was changed from the currently set ultrafiltration flow rate to 0.2 l / hr, the change was not reflected for 30 minutes, but in this embodiment, the code of the upper limit level is not changed. Since the setting is changed to 0001, the measuring tank 15 has an effective capacity of 100 ml / 16 = 6.7 ml, and the time in which the setting change is reflected is reduced to 1/16.

Next, FIG. 5 shows A / D conversion of each measurement signal of the hydrogen ion concentration and the solution conductivity in the heating tank 3, setting of the upper limit level of the filtrate in the ultrafiltration amount measuring tank 15 in each sequence, and detection of the liquid level. 9 is a flowchart showing a routine for reading a signal by means 53.

In this flow, first, in step 1, the liquid in the heating tank 3 is determined. In step 1-1, the pH value measured by the hydrogen ion concentration measurement circuit 38 via the hydrogen ion concentration measurement electrode 54 is A. The data is converted into digital data by the / D converter 37 and read into the register of the CPU 31. Next, step 1-
In step 2, the value of the solution in the heating tank 3 is determined based on this value. This is performed by reading in advance that the pH value of each solution is stored in the ROM 32. In this embodiment, the dialysate and water are set at pH 6.6 to 7.4, the disinfecting hypochlorous acid solution is set at pH 10 to 12, and the acetic acid solution for acid washing is set at pH 3 to 5. Therefore, for example, when the pH of the measured solution is 7.1, it is determined that the solution is either dialysate or water. Next, in step 1-3, the CPU 31 measures the electric conductivity by the electric conductivity electrode 55 and the electric conductivity measuring circuit 39 only when the judgment result is either dialysate or water as in the present case.
The value of the conductivity of the solution converted into digital data by the D converter 37 is read into a register of the CPU 31. If it is determined in step 1-2 that the solution is another solution, step 1-3 is not performed.

Next, in step 1-4, the CPU 31 determines whether it is dialysate or water based on the value of the electric conductivity read into the register. In this embodiment, the electric conductivity range of the dialysate is stored in the ROM 32 in advance in the range of 11.5 to 16.0 ms. Is set, and in the case of water, it is set to 1 mS or less. Therefore, for example, when the value of the read solution conductivity is 12.7 mS, the CPU 31 determines that the solution is a dialysate. In these steps 1-1 to 1-4, CPU3
1 distinguishes the solution supplied to the heating tank 3 into one of a dialysate, a hypochlorous acid solution, an acetic acid solution, and water. If a value outside the set range of each solution is read in the above steps, the CPU 31 issues an alarm (this part is not shown). The sequence is read, which is divided into the case of preparation, dialysis, and blood return, the case of disinfection, and the case of washing (in the case of dialysis, described in FIG. 4). Since the liquid supply is performed from the multi-person dialysate supply device, the dialysate is supposed to be supplied in each of the preparation, dialysis, and blood return sequences. The sequence on the dialysate supply device side is usually not distinguished. In other words, the hypochlorous acid solution, the acid cleaning solution, and the water are supplied in this order. In this embodiment, disinfection and cleaning 2
One is one sequence. Therefore, in this sequence, the three types of solutions are supplied. Then CPU31
Compares the type of the solution determined in step 1 with the sequence read in step 2 in step 3. When an unsuitable combination occurs, an alarm is issued (not shown). For example, the case where the determined solution is a dialysate in the sequence of disinfection and cleaning.

Next, at step 4, the set liquid level upper limit level for each solution in each sequence is checked. This is, as described above, in the case of dialysate, A = 0, B = 1, C = 0,
A = 1, B = 0, C = 1, D = 1 for a hypochlorous acid solution or an acid washing solution for D = 1, and A = 1, B = 1, C for water. = 1, D = 1, and this pattern is also stored in the ROM 32. For example, if the current sequence is disinfection / cleaning and the determined liquid is a hypochlorous acid solution, the CPU 31 first reads a signal obtained by processing the output of the liquid level detecting means 53 in the sensor signal processing circuit 40,
The liquid level is calculated from the value. For example, A = 0, B =
When 0, C = 0 and D = 1, A × 1 + B × 2 + C ×
4 + D × 8 = 8. Next, the storage pattern (set upper limit level) of the ROM 32 (in this case, A = 0, B = 0, C
= 1, D = 1) to obtain a value of 12. Therefore, since the value of the set upper limit level is larger than the detection level, the CPU 31 sends the drain electromagnetic valve 18 via the I / O 35 and the drive circuit 36.
Is closed. When the liquid level rises and matches (or exceeds) the set upper limit level, the drain electromagnetic valve 18 is opened. In this way, the CPU 31
The liquid level upper limit level control of the ultrafiltration amount measuring tank 15 is performed according to each solution.

Since the set upper limit level of the disinfectant is higher than the set upper limit level of the dialysate, calcium carbonate adhering to the inner surface of the tank can be reliably removed, and the set upper limit level of water is even higher. It can be carried out.

FIG. 6 is a view showing another method of the liquid level detecting means 53.

In FIG. 6, a square tube is set up on the float 50 in place of the flag of FIG. 2, and the same pattern as in FIG. 2 is printed on each surface of the tube. However, instead of the transparent portion in FIG. 2, a metal glossy surface is used in FIG. 6 (the black portion is the same), and correspondingly, the photo sensors 52A to 52D are of the reflection type.

To increase the detection resolution, the number of flags must be 5
If the number of squares is changed to pentagonal and hexagonal, the multilevel detection of 32 levels and 64 levels becomes possible.

In the above, a light detection method is used as the liquid level detection means 53, but a capacitance sensor or a magnetic sensor may be used instead. This invention is also applicable to acetic acid dialysis. In FIG. 1, a water removal pump 10 and an ultrafiltration amount measuring tank 15 are shown.
The drainage electromagnetic valve 18 may be branched and connected to the inlet of the liquid stop electromagnetic valve 13 and the output of the dialysate pump 9. In addition, the present invention can be applied to a personal dialysis device. In this case, since the sequence and the supply liquid correspond to each other in the device itself, the type of the supply liquid may be determined according to which sequence.

"Effect of the invention" As described above, according to the invention, in the dialysis mode, the filtrate upper limit level in the measuring tank for measuring the actual ultrafiltration amount is elastic in accordance with the set ultrafiltration flow rate. Therefore, even when the setting of the ultrafiltration flow rate is changed, the actual filtration amount for the changed value can be confirmed much faster than in the past. The operating state of the water removal pump can be checked at an early stage. In addition, the removal of water can be smoothly changed while observing the dynamics of the patient, so that the burden on doctors and other dialysis staff can be significantly reduced, and the reliability of the apparatus can be improved.

Also, the type of the supplied solution is determined, and the liquid level detection means capable of multi-level detection detects the upper limit of the liquid level in the ultrafiltration amount measuring tank according to the type of the solution. Since the relation of liquid / acid cleaning liquid <water is satisfied, it is possible to prevent calcium carbonate from adhering to the measuring tank, which has been a problem in the conventional devices. Compared with a float switch which is a conventional level sensor, not only the resolution is improved and the variable level can be detected, but also the cost can be significantly reduced. Thus, the present invention is applicable to hemodialysis equipment,
The maintainability can be significantly improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the dialysis apparatus of the present invention. FIG. 2 is a detailed view of a liquid level detecting means 53 installed in the ultrafiltration amount measuring tank of the embodiment of FIG. Figure 3 is the first
FIG. 4 is a block diagram showing a main part of the embodiment of FIG.
FIG. 5 is a flowchart showing a program for setting the ultrafiltration amount and setting the upper limit of the filtrate of the ultrafiltration amount measuring tank corresponding to the set value in the embodiment shown in FIG. 5. FIG. 5 shows the measurement signals of the hydrogen ion concentration and the conductivity. A flow chart showing a routine of A / D conversion, setting of the upper limit level of the liquid level in the ultrafiltration amount measuring tank in each sequence, reading of the same level sensor signal, and ON / OFF control of the drain solenoid valve. FIG. 7 is a detailed block diagram showing another example of the level detecting means, and FIG. 7 is a block diagram showing a conventional hemodialysis apparatus.

Claims (2)

(57) [Scope of request for utility model registration] 1. A liquid level detecting means for detecting a liquid level of an ultrafiltration amount measuring tank in multiple stages, and a dialysate supplied to the ultrafiltration amount measuring tank from a supply port of a dialyzer. Means for setting the ultrafiltration flow rate and controlling the flow rate to be maintained, the flow rate of the dialysate supplied to the supply port side of the dialyzer, and the flow rate of the dialysate discharged from the drain port of the dialyzer. Means for equalizing the flow rate, a memory storing a correspondence table between the set ultrafiltration flow rate and the liquid level upper limit level corresponding to a higher liquid level upper level as the set ultrafiltration flow rate is larger, and in a dialysis mode, Means for reading out the liquid level upper limit level from the memory according to the set value of the ultrafiltration flow rate, and setting the same in the ultrafiltration amount measuring tank. 2. In a cleaning mode, a disinfecting solution, an acid cleaning solution,
Means for judging water and water, and in accordance with the type of the discriminated liquid, the upper limit level of each liquid level in the ultrafiltration flow rate measuring tank is set as the dialysate upper limit level set in the dialysis mode <the disinfectant / acid washing liquid upper limit. Means for setting the positional relationship of level <water upper limit level, and the liquid level of the ultrafiltration amount measuring tank to be lower than or equal to the upper limit level set according to the liquid, with reference to the liquid level detecting means. 2. The hemodialysis apparatus according to claim 1, further comprising control means.