Method for adjusting dialysate flow rate and hemodialysis apparatus

Abstract

To provide a method for adjusting the dialysate flow rate and a hemodialysis apparatus that can quickly adjust the dialysate flow rate to a desired flow rate. [Solution] The method for adjusting the dialysate flow rate 100 includes: a pump control value determination step in which a pump control value corresponding to a desired dialysate flow rate is determined based on a calibration value that shows the correlation between a desired dialysate flow rate and the pump control value of the circulation pump 92; a pump operation step in which the circulation pump is operated with the pump control value determined in the pump control value determination step; a difference calculation step in which the difference between the current dialysate flow rate and the desired dialysate flow rate is calculated; and a calibration value correction step in which the calibration value is corrected based on the difference calculated in the difference calculation step.

Description

Technical Field

[0001] The present invention relates to a method for adjusting the dialysis fluid flow rate and a hemodialysis apparatus.

Background Art

[0002] In a hemodialysis apparatus, it is required to adjust the dialysis fluid flow rate according to the patient's condition and the difference in the dialysis treatment method. Patent Document 1 discloses a hemodialysis apparatus that adjusts the dialysis fluid flow rate to a flow rate corresponding to the blood flow rate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in a conventional hemodialysis apparatus, it is difficult to quickly adjust the dialysis fluid flow rate to a desired flow rate and complete the adjustment.

[0005] An object of the present invention is to provide a method for adjusting the dialysis fluid flow rate and a hemodialysis apparatus that can quickly adjust the dialysis fluid flow rate to a desired flow rate and complete the adjustment.

Means for Solving the Problems

[0006] The present invention relates to a method for adjusting the dialysate flow rate in a hemodialysis apparatus comprising a dialysate circuit and a circulating pump provided in the dialysate circuit, and comprises: a pump control value determination step in which a pump control value corresponding to the desired dialysate flow rate is determined based on a calibration value that shows the correlation between the desired dialysate flow rate and the pump control value of the circulating pump; a pump operation step in which the circulating pump is operated with the pump control value determined in the pump control value determination step; a difference calculation step in which the difference between the current dialysate flow rate and the desired dialysate flow rate is calculated; and a calibration value correction step in which the calibration value is corrected based on the difference calculated in the difference calculation step.

[0007] The method for adjusting the dialysate flow rate of the present invention may involve repeating the pump control value determination step, the pump operation step, the difference calculation step, and the calibration value correction step until the difference falls within a predetermined tolerance range.

[0008] The dialysate flow rate adjustment method of the present invention may also be performed when the circulation pump is operated with a new pump control value, by executing the difference calculation step and the calibration value correction step.

[0009] The method for adjusting the dialysate flow rate of the present invention may involve performing the difference calculation step at predetermined intervals, and if the difference calculated in the difference calculation step exceeds a predetermined value, the calibration value correction step may be performed.

[0010] The hemodialysis apparatus of the present invention comprises a dialysate circuit and a circulating pump provided in the dialysate circuit, wherein the output of the circulating pump changes according to a set pump control value, the pump control value is determined based on a calibration value that shows the correlation between a desired dialysate flow rate and the pump control value, and the apparatus comprises a flow rate calculation unit that calculates the dialysate flow rate of the dialysate circuit, and a correction value calculation unit that corrects the calibration value based on the difference between the dialysate flow rate calculated by the flow rate calculation unit and a desired dialysate flow rate corresponding to the set pump control value.

[0011] The hemodialysis apparatus of the present invention includes a correction value calculation unit and a correction value adjustment unit. The correction value adjustment unit may, with respect to the continuously calculated dialysate flow rate, adjust the ratio of the correction amount to the difference between the calculated dialysate flow rate and the desired dialysate flow rate when the circulation pump is operated with a pump control value determined based on the calibration value before correction, to the ratio of the correction amount to the difference between the calculated dialysate flow rate and the desired dialysate flow rate when the circulation pump is operated with a pump control value determined based on the calibration value after correction, when the relationship between the magnitudes of the calculated dialysate flow rate and the desired dialysate flow rate is reversed, in the next correction of the calibration value, make the ratio of the correction amount to the difference between the calculated dialysate flow rate and the desired dialysate flow rate smaller than the previous correction of the calibration value.

[0012] The hemodialysis apparatus of the present invention includes a correction value calculation unit which is outside the dialysate flow rate range determination unit which determines whether the difference between the current dialysate flow rate and the desired dialysate flow rate exceeds a predetermined range, and the correction value calculation unit may correct the calibration value if the dialysate flow rate range determination unit determines that it exceeds a predetermined value. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a method for adjusting the dialysate flow rate and a hemodialysis apparatus that can quickly adjust the dialysate flow rate to a desired flow rate. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 shows the overall configuration of a hemodialysis apparatus according to one embodiment of the present invention. [Figure 2] Figure 2 is a diagram showing some of the lines and valves of a hemodialysis machine according to one embodiment of the present invention. [Figure 3] Figure 3 is a block diagram showing an overview of the various parts of the hemodialysis apparatus according to Embodiment 1 of the present invention. [Figure 4] Figure 4 shows an example of the display on the display unit of Embodiment 1 of the present invention. [Figure 5] Figure 5 shows a linear equation in Embodiment 1 of the present invention. [Figure 6]FIG. 6 is a flowchart showing the processing flow of the method for adjusting the dialysate flow rate according to the present embodiment. [Figure 7] FIG. 7 is a diagram showing the change in the current dialysate flow rate by correction. [Figure 8] FIG. 8 is a diagram showing the change in the current dialysate flow rate by correction with the changed correction width. [Figure 9] FIG. 9 is a block diagram showing an overview of each part included in the hemodialysis device according to a modified example of the embodiment of the present invention. [Figure 10] FIG. 10 is a diagram showing an example of the display on the display unit according to Embodiment 2 of the present invention. [Figure 11] FIG. 11 is a diagram showing each linear formula in Embodiment 2 of the present invention. [Figure 12] FIG. 12 is a block diagram showing an overview of each part included in the hemodialysis device according to a modified example of the embodiment of the present invention. [Figure 13] FIG. 13 is a diagram showing an example of the timing for calculating the dialysate flow rate.

MODE FOR CARRYING OUT THE INVENTION

[0015] (Embodiment 1) A preferred embodiment of the method for adjusting the dialysate flow rate according to Embodiment 1 of the present invention and the personal hemodialysis device 1 with a dialysate flow rate adjustment function will be described with reference to the drawings. The personal hemodialysis device 1 is a device that purifies the blood of patients with renal failure and drug poisoning, removes excess water in the blood, and replenishes water in the blood, that is, performs fluid replacement as necessary. The personal hemodialysis device 1 is an example of a hemodialysis device, and the hemodialysis device of the present invention is not limited to the personal hemodialysis device 1.

[0016] The overall configuration of the personal hemodialysis device 1 will be described with reference to FIG. 1. FIG. 1 is a diagram showing the overall configuration of the personal hemodialysis device 1 of the present embodiment. The personal hemodialysis device 1 includes a dialyzer 10, a blood circuit 20, a dialysate circuit 30, a replenishing fluid line 38, and a console 100. In the console 100, a part of the blood circuit 20, a part of the dialysate circuit 30, a heater 40, a chemical solution pump 231, a replenishing fluid pump 39, a control unit 50, an operation unit 70, and a display unit 80 are arranged.

[0017] In the personal hemodialysis device 1, the dialysate is not supplied from the outside to the console 100 as a pre-prepared appropriate dialysate, but is prepared in the console 100. The preparation of the dialysate in the console 100 will be described later.

[0018] The dialyzer 10 includes a container body 11 formed in a cylindrical shape and a dialysis membrane (not shown) housed inside the container body 11. The inside of the container body 11 is partitioned by the dialysis membrane into a blood-side flow path and a dialysate-side flow path. These are not shown in the figure. In the container body 11, a blood inlet 111 and a blood outlet 112 communicating with the blood-side flow path, and a dialysate inlet 113 and a dialysate outlet 114 communicating with the dialysate-side flow path are formed.

[0019] The blood circuit 20 includes an arterial line 21, a venous line 22, and a drug line 23. In addition, an overflow line 24 may be provided. The arterial line 21, the venous line 22, and the drug line 23 are mainly composed of flexible tubes through which liquid can flow.

[0020] The tubes constituting the arterial line 21, the venous line 22, and the drug line 23 are formed of flexible tubes such as polyvinyl chloride or silicon, for example. The outer diameter of the tube can be, for example, 5.5 mm, and the inner diameter can be, for example, 3.3 mm. The hardness of the tube can be, for example, in the range of 50 or more and 85 or less in JIS K7215.

[0021] One end of the arterial line 21 is connected to the artery of the dialysis subject, i.e., the dialysis patient, and the other end is connected to the blood inlet 111 of the dialyzer 10.

[0022] A portion of the arterial line 21 is positioned in the console 100. A blood pump 212 is positioned in the console 100 through the portion where the arterial line 21 passes.

[0023] The blood pump 212 pumps out blood, priming fluid, and other fluids from inside the arterial line 21 by squeezing the tube that makes up the arterial line 21 with a roller.

[0024] One end of the venous line 22 is connected to the blood outlet 112 of the dialyzer 10, and the other end is connected to the subject's vein.

[0025] A venous chamber 222 is positioned in the middle of the venous line 22. The venous chamber 222 is located between the dialyzer 10 and the console 100 in the venous line 22. The venous chamber 222 stores a predetermined amount of blood, for example, 20 ml. A venous clamp 112d is also positioned between the venous chamber 222 and the patient-side end of the venous line 22.

[0026] The drug line 23 supplies the necessary drugs to the arterial line 21 during hemodialysis. One end of the drug line 23 is connected to a drug solution pump 231 that delivers the drugs, and the other end is connected between the blood pump 212 and the dialyzer 10 in the arterial line 21.

[0027] If an overflow line 24 is provided, one end of the overflow line 24 is connected to the venous chamber 222 at its proximal end. The overflow line 24 is a line for discharging saline solution and air flowing through the venous line 22 to the outside during the priming process. An overflow clamp 241 is placed on the overflow line 24. The overflow clamp 241 opens and closes the flow path of the overflow line 24.

[0028] In the blood circuit 20, blood drawn from the subject's artery is pumped by a blood pump 212 through the arterial line 21 and introduced into the blood flow path of the dialyzer 10. The blood introduced into the dialyzer 10 is purified by dialysate flowing through the dialysate circuit 30 (described later) via a dialysis membrane. The purified blood in the dialyzer 10 is returned to the subject's vein through the venous line 22.

[0029] In this embodiment, the dialysate circuit 30 is composed of a so-called sealed volume control type dialysate circuit 30. The dialysate circuit 30 includes a dialysate chamber 31, a stock solution supply line 32, a dialysate introduction line 33, a dialysate outlet line 34, a first drain line 35, a second drain line 36 as a drain line, a water removal / reverse filtration pump 37 as a pump, a circulation pump line 90, and a circulation pump 92. The dialysate circuit 30 in this embodiment includes a plurality of dialysate chambers as the dialysate chamber 31, such as a first dialysate chamber 31A and a second dialysate chamber 31B. In the following description, when there is no need to particularly distinguish between the first dialysate chamber 31A and the second dialysate chamber 31B, the first dialysate chamber 31A and the second dialysate chamber 31B together will simply be referred to as the dialysate chamber 31.

[0030] The dialysate chamber 31 comprises a rigid container 311 capable of holding a certain volume of dialysate, and a flexible diaphragm 312 that partitions the inside of the container 311. The certain volume can be, for example, 300 ml or more and 500 ml or less. The aforementioned flexible diaphragm is also called a diaphragm. The inside of the dialysate chamber is partitioned by the diaphragm 312 into a fluid supply section 313 and a drainage section 314.

[0031] The fluid supply and containment section 313 of the first dialysate chamber 31A is referred to as the first fluid supply and containment section 313A, and the fluid supply and containment section 313 of the second dialysate chamber 31B is referred to as the second fluid supply and containment section 313B. The drain fluid containment section 314 of the first dialysate chamber 31A is referred to as the first drain fluid containment section 314A, and the drain fluid containment section 314 of the second dialysate chamber 31B is referred to as the second drain fluid containment section 314B.

[0032] The base end of the concentrate supply line 32 is connected to an RO water tank, a concentrate A tank, and a concentrate B tank (not shown), and the tip end is connected to the dialysate chamber 31. The concentrate supply line 32 supplies RO water, concentrate A, and concentrate B, which are the raw materials for dialysate, to the first fluid supply storage section 313A and the second fluid supply storage section 313B of the dialysate chamber 31. When there is no need to distinguish between concentrate A and concentrate B, or when referring to both concentrate A and concentrate B, the terms concentrate or dialysate concentrate are used instead of concentrate A and concentrate B.

[0033] The dialysate introduction line 33 connects the dialysate chamber 31 to the dialysate inlet 113 of the dialyzer 10. The dialysate introduction line 33 introduces the dialysate contained in the first fluid delivery section 313A and the second fluid delivery section 313B of the dialysate chamber 31 into the dialysate side flow path of the dialyzer 10.

[0034] The dialysate outlet line 34 connects the dialysate outlet 114 of the dialyzer 10 to the dialysate chamber 31. The dialysate outlet line 34 leads the dialysate discharged from the dialyzer 10 to the first drainage container 314A and the second drainage container 314B of the dialysate chamber 31.

[0035] The proximal end of the first drainage line 35 is connected to the dialysate chamber 31 and discharges the dialysate contained in the first drainage storage section 314A and the second drainage storage section 314B.

[0036] The second drainage line 36 has its proximal end connected to the dialysate outlet line 34 and discharges the dialysate flowing through the dialysate outlet line 34.

[0037] The ultrafiltration / reverse filtration pump 37 is located in the second drain line 36. The ultrafiltration / reverse filtration pump 37 consists of a pump that is driven to deliver dialysate from inside the second drain line 36 in a direction that flows towards the discharge side (forward direction) and in a direction that flows towards the dialysate outlet line 34 (reverse direction). The direction in which dialysate flows towards the discharge side is called the ultrafiltration direction. The direction in which dialysate flows towards the dialysate outlet line 34 is called the reverse filtration direction.

[0038] The circulating pump line 90 is positioned to bypass the dialysate outlet line 34.

[0039] The circulation pump 92 is located in the circulation pump line 90. The circulation pump 92 can facilitate the flow of dialysate in the dialysate circuit 30, among other things.

[0040] The heater 40 heats the dialysate flowing through the dialysate circuit 30 to a predetermined temperature.

[0041] The replacement fluid line 38 is a line for directly supplying dialysate as replacement fluid to the blood circuit 20. The upstream side of the replacement fluid line 38 is connected between the dialysate chamber 31 in the dialysate inlet line 33 of the dialysate circuit 30 and the dialysate inlet 113 of the dialyzer 10.

[0042] A replenishment clamp is provided in the replenishment liquid line 38. The replenishment clamp provided in the replenishment liquid line 38 during pre-dilution is replenishment liquid clamp 381, and the replenishment liquid clamp provided in the replenishment liquid line 38 during post-dilution is replenishment liquid clamp 382.

[0043] As shown by the solid line in Figure 1, if the downstream side of the replacement fluid line 38 is connected between the blood pump 212 and the dialyzer 10 in the arterial line 21, it becomes a pre-dilution type hemodiafiltration. As shown by the dashed line in Figure 1, if the downstream side of the replacement fluid line 38 is connected to the venous chamber 222 in the venous line 22, it becomes a post-dilution type hemodiafiltration.

[0044] The control unit 50 is composed of an information processing device, such as a computer. The control unit 50 controls the operation of the entire personal hemodialysis machine 1 by executing a control program in the information processing device. The control unit 50 controls and operates the personal hemodialysis machine 1 by executing control programs for various processes. Specifically, the control unit 50 controls the operation of various pumps, clamps, and heaters 40, etc., arranged in the blood circuit 20 and dialysate circuit 30, to execute various processes performed by the personal hemodialysis machine 1. These various processes include, for example, the priming process, blood withdrawal process, dialysis process, fluid replacement process, and blood return process.

[0045] In the various processes of the personal hemodialysis device 1 of this embodiment, for example, the priming process, blood withdrawal process, dialysis process, and blood return process are performed in this order, and the total execution time for all these processes is approximately 4 to 5 hours.

[0046] The priming process is a preparatory process that involves washing and purifying the blood circuit 20 and dialyzer 10. The blood withdrawal process is the process of filling the blood circuit 20 with the patient's blood after puncture and circulating it outside the body. The dialysis process follows the blood withdrawal process and involves dialysis to purify the blood. The fluid replacement process is a process of rapid fluid replacement performed during dialysis treatment, such as when blood pressure drops. The blood return process is the process of returning the blood in the blood circuit 20 back into the patient's body.

[0047] The above describes an example of a personal hemodialysis machine 1. The arrangement of lines and valves in the console 100 of this embodiment will now be described in more detail with reference to Figure 2. Figure 2 is a diagram showing some of the lines and valves arranged in the console 100. Figure 2 and the diagrams described below do not show all the lines, valves, and components arranged in the console 100. Figure 2 and the diagrams described below mainly show the parts related to the dialysate chamber 31. Furthermore, there are differences in the configuration between the personal hemodialysis machine 1 described with reference to Figure 1 and the personal hemodialysis machine 1 described below with reference to Figure 2, etc. In either configuration, any configuration in which the technology of this disclosure can be implemented is included in the embodiments of this disclosure.

[0048] (Configuration related to the preparation of dialysate) The configuration for preparing dialysate in a personal hemodialysis machine 1 will now be described. In this embodiment, dialysate is prepared in the console 100. Specifically, dialysate is prepared in each dialysate chamber 31, and the prepared dialysate is stored in the dialysate chamber 31. Dialysate is prepared, for example, by mixing RO water, stock solution A, and stock solution B.

[0049] The personal hemodialysis machine 1 includes an RO water line L10, a degassing pump P1, a first solenoid valve SV1, and a third solenoid valve SV3 as components for preparing the dialysate. In Figure 2 and other figures, open valves are drawn in white and closed valves are drawn in black. First, RO water is supplied from one end of the RO water line L10. The other end of the RO water line L10 is connected to each dialysate chamber 31 via a solenoid valve. More specifically, the other end of the RO water line L10 branches into two at the junction J14 before being connected to each dialysate chamber 31. One of the branches is connected to the first fluid supply container 313A via the first solenoid valve SV1. The other branch is connected to the second fluid supply container 313B via the third solenoid valve SV3.

[0050] The degassing pump P1 is installed in the RO water line L10.

[0051] The personal hemodialysis machine 1 further includes a stock solution line L11, a stock solution tank A TA, a stock solution tank B TB, a solenoid valve SVA for stock solution A, a solenoid valve SVB for stock solution B, and a stock solution pump P2.

[0052] One end of the concentrate line L11 is connected to concentrate tank A TA and concentrate tank B TB. More specifically, one end of concentrate line L11 is connected to concentrate tank A TA via solenoid valve SVA for concentrate A, and to concentrate tank B TB via solenoid valve SVB for concentrate B. The point in concentrate line L11 where concentrate tank A TA and concentrate tank B TB are connected is called the junction point J16.

[0053] The other end of the stock solution line L11 is connected to the upstream side of junction point J14 in the RO water line L10. The point in the RO water line L10 where the other end of the stock solution line L11 is connected is called junction point J12.

[0054] The concentrate pump P2 is located downstream of the junction J16 in the concentrate line L11.

[0055] The personal hemodialysis machine 1 is further equipped with an auxiliary RO water line L12 and an auxiliary line solenoid valve SVC.

[0056] One end of the auxiliary RO water line L12 is connected to the RO water line L10, downstream of the degassing pump P1 and upstream of the connection point J12. The point on the RO water line L10 where the auxiliary RO water line L12 is connected is called the connection point J10.

[0057] The other end of the auxiliary RO water line L12 is connected to junction J16.

[0058] The auxiliary line solenoid valve SVC is installed in the auxiliary RO water line L12.

[0059] The dialysis fluid is prepared, for example, by injecting concentrate A, concentrate B, and RO water into a dialysis fluid chamber 31 with a volume of 300 ml in a set ratio. The injection is carried out in the order of RO water, concentrate A, RO water, concentrate B, and RO water. If concentrate A and concentrate B are mixed directly, they may react and form compounds. During the injection process of concentrate A and concentrate B, care must be taken to prevent direct mixing of concentrate A and concentrate B within the line. In other words, contact between concentrate A and concentrate B within the line must be avoided.

[0060] The preparation of the dialysate is completed when predetermined amounts of each fluid are injected into the dialysate chamber 31 and mixed together.

[0061] The method for adjusting the dialysate flow rate and the personal hemodialysis device 1 of Embodiment 1 will be described. Here, dialysate flow rate refers to the flow rate of dialysate in the dialysate circuit 30.

[0062] Referring to Figure 3, the control unit 50 and other components of the personal hemodialysis machine 1 of Embodiment 1 will be described in more detail. Figure 3 is a block diagram showing the various parts of the console 100. As shown in Figure 1, the console 100 includes a control unit 50, an operation unit 70, and a display unit 80.

[0063] The display unit 80 can be, for example, a liquid crystal display. The display unit 80 may also have a touch panel. The display unit 80 can display the set value of the dialysate flow rate and the current dialysate flow rate, etc.

[0064] The dialysate flow rate that the user wants to set is called the desired dialysate flow rate. The user can input the desired dialysate flow rate from the control unit 70. The input method can be by pressing a button on the control unit 70 or by touching a touch panel on the control unit 70. The control unit 70 may be integrated with the display unit 80.

[0065] The desired dialysate flow rate value entered by the user via the control unit 70 or the like is called the dialysate flow rate setting value.

[0066] The control unit 50 includes a calibration value storage unit 501, a pump control unit 503, a calibration value calculation unit 505, a correction value calculation unit 507, and a flow rate calculation unit 509.

[0067] The calibration value calculation unit 505 is the part that calculates the calibration value. The calibration value is a relationship between the desired dialysate flow rate and the pump control value. The calibration value calculation unit 505 calculates the desired dialysate flow rate, the pump control value, and the relationship between them. The pump control value will be explained later.

[0068] The calibration value storage unit 501 is the part that stores the calibration value calculated by the calibration value calculation unit 505.

[0069] The flow rate calculation unit 509 is responsible for calculating the current dialysate flow rate. The desired dialysate flow rate is a set value, while the current dialysate flow rate is the actual flow rate of the dialysate.

[0070] The correction value calculation unit 507 is responsible for calculating the correction value of the pump control value. The correction value calculation unit 507 calculates the correction value of the pump control value from the difference between the set value of the dialysate flow rate and the current dialysate flow rate calculated by the flow rate calculation unit 509. In other words, the correction value calculation unit 507 calculates the correction value of the pump control value from the difference between the desired dialysate flow rate and the current dialysate flow rate.

[0071] Calculating a correction value for pump control values ​​means, for example, determining the range by which to correct the calibration value.

[0072] The pump control unit 503 controls the operation of the circulation pump 92 based on calibration values ​​and correction values. Specifically, the pump control value is determined based on the calibration values ​​and correction values. The determined pump control value is stored, for example, in the calibration value storage unit 501. The pump control unit 503 uses the pump control value stored in the calibration value storage unit 501 to control the operation of the circulation pump 92 and control the pump discharge rate. The specific functions of each part of the control unit 50 will be described in order below.

[0073] The general method for adjusting the dialysate flow rate in this embodiment is as follows: The calibration values ​​for the pump control value and the dialysate flow rate are stored in the console 100 in advance.

[0074] The pump control value is a value that defines the output of the circulation pump 92. The pump control value can be, for example, a PWM (Pulse Width Modulation) signal. However, the pump control value is not limited to a PWM signal; it can also be a value other than a PWM signal, such as a current value, a voltage value, or an analog signal.

[0075] The storage of calibration values ​​in the console 100, that is, the input of calibration values ​​to the calibration value storage unit 501, can be performed, for example, during the manufacturing of the console 100. Alternatively, calibration values ​​may be determined by user instructions, and the determined calibration values ​​may be stored in the calibration value storage unit 501.

[0076] When using console 100, the dialysate flow rate is adjusted using the stored calibration values. For example, the dialysate flow rate is adjusted so that the current dialysate flow rate matches the dialysate flow rate entered into the control unit 70, i.e., the desired dialysate flow rate.

[0077] Specifically, based on the calibration values, the pump control values ​​corresponding to the desired dialysate flow rate are determined. The dialysate flow rate is calculated when the circulation pump is operated with the determined pump control values. The difference between the calculated dialysate flow rate, i.e., the current dialysate flow rate, and the desired dialysate flow rate is determined. Based on the obtained difference, the calibration values ​​are corrected by the difference correction.

[0078] Then, a new pump control value is determined based on the differentially corrected calibration value, and the circulating pump is operated using this new pump control value. This procedure makes it possible to quickly adjust the dialysate flow rate.

[0079] Furthermore, if there is a difference between the current dialysate flow rate after differential correction and the desired dialysate flow rate, the calibration value may be further differentially corrected. This allows the current dialysate flow rate to quickly approach the desired flow rate. A more detailed explanation follows.

[0080] Embodiment 1 involves calculating calibration values ​​at two points. That is, the calibration value between the desired dialysate flow rate and the pump control value is determined based on two points and shown by a single straight line. The circulation pump 92 is assumed to be, for example, a gear-type pump. The pump control value is assumed to be, for example, a PWM signal. By inputting the PWM signal to the circulation pump 92, voltage control or current control is performed in the electronic circuit of the circulation pump 92. This voltage control or current control can change the pump discharge amount of the circulation pump 92.

[0081] The personal hemodialysis machine 1 of Embodiment 1 is assumed to be a system in which the PWM signal and the dialysate flow rate have a linear relationship. Currently, the dialysate flow rate becomes low when the pump control value is decreased, and high when it is increased.

[0082] Referring to Figure 4, Embodiment 1 will be described using the example of a case where the calibration value is determined by user instructions. Figure 4 is a diagram showing an example of the display on the display unit 80 in this embodiment. For example, the calibration value is calculated when the user presses the adjustment start button on the display unit 80.

[0083] The calibration value calculation unit 505 sets two points for dialysate flow rate: low flow rate 1 and high flow rate 1. The calibration value calculation unit 505 calculates calibration values ​​for the pump control value and dialysate flow rate at these two points: low flow rate 1 and high flow rate 1.

[0084] As calibration coordinate value 1, pump control value 1 is determined, and the current dialysate flow rate calculated using pump control value 1 is set as low flow rate 1. Then, similarly, as calibration coordinate value 2, pump control value 2 is determined, and the current dialysate flow rate calculated using pump control value 2 is set as high flow rate 1.

[0085] The derivation of calibration values ​​between the pump control value and the current dialysate flow rate will be explained. As a result of setting the low flow rate 1 and high flow rate 1 as described above, calibration coordinate value 1 (pump control value 1, low flow rate 1) and calibration coordinate value 2 (pump control value 2, high flow rate 1) are obtained. Then, from calibration coordinate value 1 and calibration coordinate value 2, the linear equation 1 (Y=a·X+b) between the two points can be calculated. Figure 5 shows the linear equation 1 (Y=a·X+b). The calibration value storage unit 501 stores this linear equation 1 as the calibration value.

[0086] (Flow rate adjustment) The flow rate adjustment will now be explained. When the desired dialysate flow rate (Y) is set in the control unit 70, the pump control value (X) is determined from the linear equation 1 (Y=a·X+b) stored in the calibration value storage unit 501.

[0087] The pump control value (X) determined based on linear equation 1 is input to the circulation pump 92. This controls the circulation pump 92, and the pump discharge rate of the circulation pump 92 changes.

[0088] The flow rate calculation unit 509 calculates the current dialysate flow rate (Y'), which is the actual flow rate of the dialysate. Since the current dialysate flow rate (Y') is the flow rate obtained using calibration values, it will be close to the desired dialysate flow rate (Y).

[0089] Next, linear equation 1 is corrected based on the difference (c) between the desired dialysate flow rate (Y) and the current dialysate flow rate (Y'). For example, linear equation 1 is shifted so that the difference (c) becomes zero. However, if the difference (c) is not large, the linear equation 1 may not be corrected, and the flow rate adjustment control may be terminated.

[0090] For example, if the current dialysate flow rate (Y') is within a predetermined range relative to the desired dialysate flow rate (Y), the flow rate adjustment control can be terminated. For example, if the current dialysate flow rate is Desired dialysate flow rate - 5 mL / min ≤ Current dialysate flow rate ≤ Desired dialysate flow rate + 5 mL / min In this case, further flow rate adjustment control can be avoided. In other words, if the current dialysate flow rate (Y') is within a predetermined tolerance range relative to the desired dialysate flow rate (Y), the flow rate adjustment control can be terminated.

[0091] In contrast, if the current dialysate flow rate (Y') is not within a predetermined tolerance range relative to the desired dialysate flow rate (Y), the flow rate adjustment control can be continued. For example, if the current dialysate flow rate is Desired dialysate flow rate - 5 mL / min ≤ Current dialysate flow rate ≤ Desired dialysate flow rate + 5 mL / min Otherwise, flow rate control can be continued.

[0092] Note that 5 mL / min in the above formula is an example. The acceptable range of deviation between the current dialysate flow rate (Y') and the desired dialysate flow rate (Y) can be set arbitrarily.

[0093] The process for continuing flow rate adjustment control will now be explained. The correction value calculation unit 507 calculates the difference (c) between the desired dialysate flow rate (Y) and the current dialysate flow rate (Y'). Then, the calibration value calculation unit 505 shifts linear equation 1 by the difference (c) to obtain the calibration value Y = a·X' + b + c. Next, the correction value calculation unit 507 corrects the pump control value from (X) to (X') and inputs the corrected pump control value X' back into the pump control unit 503.

[0094] Then, the same procedure is repeated until the current dialysate flow rate (Y') calculated by the flow rate calculation unit 509 falls within the acceptable range of deviation from the desired dialysate flow rate (Y).

[0095] The current dialysate flow rate is, for example, as described above. Desired dialysate flow rate - 5 mL / min ≤ Current dialysate flow rate ≤ Desired dialysate flow rate + 5 mL / min The flow rate adjustment control is terminated when the given equation is satisfied. In other words, the flow rate adjustment control is terminated when the current dialysate flow rate falls within the acceptable deviation range from the desired dialysate flow rate. If the current dialysate flow rate (Y') calculated by the flow rate calculation unit 509 is not within the acceptable deviation range from the desired dialysate flow rate (Y), the same flow rate adjustment control procedure is repeated.

[0096] As described above, by correcting the calibration values ​​between the desired dialysate flow rate (Y) and the pump control value (X), and bringing them closer to the actual relationship between the pump control value and the dialysate flow rate, it becomes possible to quickly adjust the dialysate flow rate to the desired flow rate.

[0097] Referring to Figure 6, the procedure for adjusting the dialysate flow rate in this embodiment will be described. Figure 6 is a flowchart showing the processing flow of the dialysate flow rate adjustment method in this embodiment. In Figure 6 and the following description, S1 means step 1. The same applies to the other steps. Note that the flow shown in Figure 6 is an example of the dialysate flow rate adjustment method in this embodiment. The dialysate flow rate adjustment method in this embodiment is not limited to the flow shown in Figure 6 and can be modified in various ways.

[0098] (S1) S1 is the calibration value storage step. The calibration value is the calibration value between the pump control value and the desired dialysate flow rate. The calibration value is calculated by the calibration value calculation unit 505 and stored in the calibration value storage unit 501. The calibration value storage step may be performed during the manufacture of the personal hemodialysis machine 1, or it may be performed at the request of the user.

[0099] (S2) S2 is the first circulating pump operation step. In S2, the circulating pump is operated with a pump control value calculated using a calibration value for the desired dialysate flow rate.

[0100] (S3) S3 is the first difference calculation step. In S3, the difference (c) between the current dialysate flow rate (Y'), which is the actual flow rate of the dialysate, and the desired dialysate flow rate (Y).

[0101] (S4) S4 is the calibration value correction step. In S4, the calibration value is corrected based on the difference (c). For example, the calibration value between the pump control value and the dialysate flow rate, which are the calibration values, is shifted by an amount based on the difference (c). For example, the calibration value is corrected by shifting the calibration value so that the difference (c) becomes zero.

[0102] (S5) S5 is the second circulating pump operation step. In S5, a new pump control value (X') obtained from the corrected calibration value is input to the pump control unit 503, and the circulating pump is started.

[0103] (S6) S6 is the second difference calculation step. In S6, the difference (c) between the current dialysate flow rate (Y'), which is the actual flow rate of dialysate based on the new pump control value (X'), and the desired dialysate flow rate (Y).

[0104] (S7) S7 is the difference determination step. In S7, it is determined whether the difference (c) calculated in S6 is within the acceptable range. If the difference (c) is not within the acceptable range, the step returns to S4. In S4, the calibration value is corrected again, and steps S5 to S7 are repeated. If the difference (c) is within the acceptable range, the flow of the dialysate flow rate adjustment method of this embodiment is completed.

[0105] (Other examples of adjusting the correction amount) Next, we will describe other examples of adjusting the correction amount. In the above explanation, linear equation 1 was corrected based on the difference (c) between the desired dialysate flow rate (Y) and the current dialysate flow rate (Y'). Specifically, linear equation 1 was corrected from (Y=a·X+b) to (Y=a·X+b+c). However, the method of correction is not limited to this example. For example, (+c) can also be (+1 / 2c) or (+1 / 4c), etc.

[0106] Figure 7 is an illustrative diagram showing a case where rapid adjustment of the flow rate is difficult with the (+c) correction. The horizontal axis L101 in Figure 7 represents the desired dialysate flow rate. In Figure 7, the arrow + indicates that the current dialysate flow rate is greater than the desired dialysate flow rate, and the arrow - indicates that the current dialysate flow rate is less than the desired dialysate flow rate.

[0107] Point P101 in Figure 7 shows the dialysate flow rate based on the calibration value before correction. Point P102 shows the dialysate flow rate based on the calibration value after the first correction. The first correction refers to the correction based on the value at point P101. Point P103 shows the dialysate flow rate based on the calibration value after the second correction. The second correction refers to the correction based on the value at point P102.

[0108] As shown in Figure 7, the dialysate flow rate at point P101 is greater than the desired dialysate flow rate. The dialysate flow rate at point P102 is less than the desired dialysate flow rate. In other words, point P102 is a transition from point P101 to point P102, exceeding the horizontal axis L101 which represents the desired dialysate flow rate. The same applies to point P103. Point P103 is a transition from point P102 to point P103, exceeding the horizontal axis L101.

[0109] If the corrected dialysate flow rate changes beyond horizontal axis L101 from the uncorrected dialysate flow rate, it means the correction range is too large. When the correction range is too large, it is usually difficult to reduce the difference (c). As a result, rapid adjustment of the dialysate flow rate becomes difficult.

[0110] Therefore, if the correction range is deemed too large, it may be possible to reduce the correction range.

[0111] Figure 8 shows the change in dialysate flow rate when the correction range is reduced. The horizontal axis L101, and the + and - directions of the arrows have the same meaning as in Figure 7. Point P101 in Figure 8 is the same point as point P101 in Figure 7. Point P111 is the point where the correction range, i.e., the range of translation, is halved compared to point 102 in Figure 7. Similarly, point 112 is the point where the correction range, i.e., the range of translation, is halved compared to point 103 in Figure 7. While point 103 in Figure 7 is about the same distance from the horizontal axis L101 as point P101, point P112 in Figure 8 is located almost on the horizontal axis L101. In other words, point P112 is approximately the desired dialysate flow rate.

[0112] In this way, by reducing the correction range by half each time a correction is made, the dialysate flow rate can be quickly adjusted to the desired dialysate flow rate.

[0113] In other words, if the current dialysate flow rate is calculated to exceed (or cross over) the desired flow rate each time the dialysate flow rate is adjusted, adjusting the dialysate flow rate may take time. In such cases, the amount of parallel shift is reduced by, for example, half each time a correction is made. That is, the first correction is made by half, the second correction by quarter, and so on. This allows the dialysate flow rate to be quickly adjusted to the desired flow rate.

[0114] Referring to Figure 9, the configuration of the control unit 50 when adjusting the correction amount described above will be explained. Figure 9 is a block diagram showing an overview of the various parts of the hemodialysis machine. The following explanation will describe the differences from the matters previously explained with reference to Figure 3. Matters not specifically explained can be the same as those shown in Figure 3.

[0115] In the control unit 50, when adjusting the correction amount, the correction value calculation unit 507 includes a correction value adjustment unit 511. The correction value adjustment unit 511 further adjusts the correction value calculated by the correction value calculation unit 507 using the method described above. Specifically, for example, if the current dialysate flow rate after the first correction changes from the current dialysate flow rate before correction to a desired dialysate flow rate, the correction value adjustment unit 511 can adjust the width of the second correction to, for example, half of the normal width. A change exceeding the desired dialysate flow rate refers to, for example, a change from the positive side to the negative side of the desired dialysate flow rate, and a change from the negative side to the positive side of the desired dialysate flow rate. Furthermore, adjusting the width of the correction to, for example, half of the normal width means, for example, setting the width c of the parallel shift to 1 / 2c.

[0116] The criteria for determining whether the dialysate flow rate has exceeded the desired rate, as described above, are illustrative examples. These criteria can be set as appropriate. Furthermore, the 1 / 2 ratio used when adjusting the correction value is illustrative; the adjustment ratio for the correction value can be set as appropriate.

[0117] Furthermore, even when adjusting the correction amount, if the difference falls within a predetermined allowable range, the differential correction, i.e., the flow rate adjustment control, can be terminated, just as in the case where no adjustment is made to the correction amount.

[0118] (Embodiment 2) Referring to Figures 10 and 11, the method for adjusting the dialysate flow rate and the personal hemodialysis device 1 of Embodiment 2 will be described. Embodiment 1 and Embodiment 2 differ in the number of points used for calibration. Embodiment 1 used two points for calibration. In contrast, Embodiment 2 uses four points for calibration. In the following description, Embodiment 2 will be described focusing on the differences from Embodiment 1. Matters not specifically described for Embodiment 2 can be the same as in Embodiment 1.

[0119] Depending on the configuration of console 100 and personal hemodialysis machine 1, the relationship between pump control values ​​such as PWM signals and dialysate flow rate may not be linear. For example, in devices with many components in the dialysate line, such as personal hemodialysis machines, the relationship between pump control values ​​and dialysate flow rate may not be linear.

[0120] In personal hemodialysis machines, components such as those for mixing RO water, concentrate A, and concentrate B may be installed in the dialysate line. In such cases, the relationship between the pump control value and the dialysate flow rate is not linear.

[0121] If the relationship between the pump control value and the dialysate flow rate is not linear, it is preferable to perform calibration, that is, determination of the calibration value, using more than two points, such as four points, rather than based on two points as in Embodiment 1. Embodiment 2 shows an example of determining the calibration value using four points.

[0122] Figure 10 shows an example of the display of the display unit 80 in Embodiment 2. As shown in Figure 10, in Embodiment 2, the calibration value is determined using four calibration coordinate values, from calibration coordinate value 1 to calibration coordinate value 4.

[0123] The dialysate flow rate is calibrated at four points: low flow rate 1, medium flow rate 1, medium flow rate 2, and high flow rate 1. Calibration coordinate value 1 corresponds to low flow rate 1, calibration coordinate value 2 corresponds to medium flow rate 1, calibration coordinate value 3 corresponds to medium flow rate 2, and calibration coordinate value 4 corresponds to high flow rate 1. In the personal hemodialysis machine 1 of Embodiment 2, the calculated dialysate flow rate becomes low when the pump control value is small, and high when it is large. The range at which the dialysate flow rate changes from a given pump control value has been determined through prior experiments.

[0124] Similar to Embodiment 1, the calibration values, i.e., the calculation of each linear equation, can be initiated by, for example, the user pressing the adjustment start button on the display unit 80.

[0125] Specifically, first, pump control value 1 is determined as calibration coordinate value 1. The dialysate flow rate calculated at that time is set as low flow rate 1. After that, pump control value 2 is determined as calibration coordinate value 2. The dialysate flow rate calculated at that time is set as medium flow rate 1. Similarly, pump control value 3 and medium flow rate 2 are set as calibration coordinate value 3, and high flow rate 1 is set as calibration coordinate value 4.

[0126] Figure 11 shows the calibration results in Embodiment 2. As shown in Figure 11, in Embodiment 2, calibration values ​​are determined at four points, so three linear equations are obtained. From calibration coordinate value 1 (pump control value 1, low flow rate 1) and calibration coordinate value 2 (pump control value 2, medium flow rate 1), a linear equation (Y1=a1·X+b1) between two points can be calculated. Similarly, from calibration coordinate value 2 (pump control value 2, medium flow rate 1) and calibration coordinate value 3 (pump control value 3, medium flow rate 2), linear equation 2 (Y2=a2·X+b2) can be calculated. Furthermore, from calibration coordinate value 3 (pump control value 3, medium flow rate 2) and calibration coordinate value 4 (pump control value 4, medium flow rate 1), linear equation 3 (Y3=a3·X+b3) can be calculated. The calibration value storage unit 501 stores linear equations 1 to 3 as calibration values.

[0127] Here, the pump control value that corresponds to the user's desired dialysate flow rate can be calculated from the minimum values ​​of Y1, Y2, and Y3. In other words, the pump control value Y4 is Y4 = min(Y1, Y2, Y3). Y4 is one of Y1, Y2, or Y3, and these values ​​are stored as calibration values ​​in the calibration value storage unit 501.

[0128] As described above, the relationship between the pump control value and the dialysate flow rate is obtained based on linear formula Y1 for low flow rate 1 to medium flow rate 1, linear formula Y2 for medium flow rate 1 to medium flow rate 2, and linear formula Y3 for medium flow rate 2 to high flow rate 1.

[0129] (Flow rate adjustment) Flow rate adjustment in Embodiment 2 will now be described. When a desired dialysate flow rate (Y) is set, X is set as the pump control value from the stored value Y4 in the calibration value storage unit 501. By inputting this to the circulation pump 92, the circulation pump 92 is controlled.

[0130] When the pump control value (X) is input, the pump discharge rate changes, and the flow rate calculation unit 509 calculates the current dialysate flow rate (Y'). Since the dialysate flow rate (Y') is a value obtained using calibration values, it will be close to the desired dialysate flow rate (Y).

[0131] So, for example, Desired dialysate flow rate - 10 mL / min ≤ Current dialysate flow rate ≤ Desired dialysate flow rate + 10 mL / min In that case, the flow rate adjustment control can be terminated.

[0132] If the current dialysate flow rate does not satisfy the above relationship, the correction value calculation unit 507 calculates the difference (c) between the desired dialysate flow rate (Y) and the current dialysate flow rate (Y'). Then, Y1, Y2, and Y3 are each shifted by the difference, i.e., the difference (c) (Y1=a1·X+b1+c, Y2=a2·X+b2+c, Y3=a3·X+b3+c).

[0133] After translating each linear equation, Y4 is calculated from Y4min(Y1, Y2, Y3) in the same way as before the translation. The corrected pump control value (X') obtained from the translated equation is input back into the control pump. This operation is repeated until the current dialysate flow rate falls within the desired dialysate flow rate range.

[0134] For example, if the current dialysate flow rate satisfies the following equation, Desired dialysate flow rate - 10 mL / min ≤ Current dialysate flow rate ≤ Desired dialysate flow rate + 10 mL / min The flow rate adjustment control can be terminated. In this way, the current dialysate flow rate can be quickly adjusted to the desired dialysate flow rate.

[0135] Furthermore, the adjustment of the correction amount described earlier in Embodiment 1, that is, setting the correction amount to, for example, 1 / 2, can also be suitably applied in Embodiment 2.

[0136] (modified version) Referring to Figures 12 and 13, a method for adjusting the dialysate flow rate and a modified example of the personal hemodialysis machine 1 will be described. Figure 12 is a block diagram showing an overview of the parts of a modified hemodialysis machine according to an embodiment of the present invention. Figure 13 is a diagram showing an example of the timing for calculating the dialysate flow rate. The modified examples described below can be applied to both Embodiment 1 and Embodiment 2.

[0137] In Embodiments 1 and 2, flow rate adjustment can be performed, for example, when the user presses the adjustment start switch on the display unit 80, or when the set value of the dialysate flow rate is changed from the operation unit 70 or the like.

[0138] This flow rate adjustment is, for example, If the current dialysate flow rate > desired dialysate flow rate + 20 mL / min, or, When the current dialysate flow rate < desired dialysate flow rate - 20 mL / min, Alternatively, the system may be configured to perform the action automatically if the above conditions persist for a certain period of time or longer.

[0139] In this case, the correction value is automatically calculated by the correction value calculation unit 507 without any user intervention. Then, the circulation pump 92 is controlled to perform the flow rate adjustment described above. This adjusts the current dialysate flow rate to a value close to the desired dialysate flow rate.

[0140] Figure 12 shows the configuration of the control unit 50 in a modified example. Figure 12 is a block diagram illustrating the outline of each part of a modified personal hemodialysis machine 1 according to an embodiment of the present invention. As shown in Figure 12, in the modified control unit 50, the correction value calculation unit 507 includes a dialysate flow rate range out-of-range determination unit 513. The dialysate flow rate range out-of-range determination unit 513 is a determination unit that determines when the difference between the current dialysate flow rate and the desired dialysate flow rate has become large. More specifically, the dialysate flow rate range out-of-range determination unit 513 determines when the difference between the current dialysate flow rate and the desired dialysate flow rate has become large enough to fall outside a predetermined range.

[0141] The dialysate flow rate range detection unit 513 can be, for example, a flow meter installed in the dialysate flow path. However, the configuration of the dialysate flow rate range detection unit 513 is not limited to a flow meter. The dialysate flow rate range detection unit 513 only needs to be capable of determining that the dialysate flow rate is outside a predetermined range.

[0142] If the dialysate flow rate range determination unit 513 determines that the dialysate flow rate is outside a predetermined range, the correction value calculation unit 507 automatically starts calculating the correction value, as described above.

[0143] Referring to Figure 13, another example of calculating the dialysate flow rate will be explained. As shown in Figures 1 and 2, when the personal hemodialysis machine 1 uses a system with two dialysate chambers 31, the dialysate flow rate can be calculated from the switching time between the dialysate chambers 31. The dialysate flow rate is calculated at the timing when the two dialysate chambers 31 switch. The timing of the dialysate chamber 31 switch can be determined by the fact that the dialysate stops flowing in the dialysate flow path of one of the dialysate chambers 31. Then, at the timing when the dialysate chambers 31 switch, the dialysate flow rate is calculated, and correction control for flow rate adjustment is performed at that time. The dialysate flow rate can be calculated based on the volume of the dialysate chamber 31 and the time until the switch. After the dialysate chamber 31 switches, the dialysate flow rate is calculated again at the timing when the dialysate chamber 31 switches again. By repeating this, it is possible to control the dialysate flow rate accurately and quickly.

[0144] The control of the dialysate flow rate will be explained based on Figure 13. The horizontal axis of Figure 13 represents time (t). First, at time T1, the desired dialysate flow rate is set. Then, the circulation pump is controlled using pump control values ​​based on calibration values. Subsequently, the first dialysate chamber operates (CV1-1), followed by the second dialysate chamber (CV2-1). At the time when the second dialysate chamber has finished operating, i.e., at time T2, the current dialysate flow rate is calculated. At this time, the dialysate flow rate may be calculated by averaging the dialysate flow rates of the two dialysate chambers. Averaging the dialysate flow rates of the two dialysate chambers allows for a more accurate calculation of the dialysate flow rate.

[0145] If the difference between the current dialysate flow rate and the desired dialysate flow rate is within a predetermined range, the flow rate adjustment is complete.

[0146] If the difference between the current dialysate flow rate and the desired dialysate flow rate is not within a predetermined range, a correction value is calculated. Then, the pump is controlled using the corrected pump control value. Specifically, the first dialysate chamber operates again (CV1-2), followed by the second dialysate chamber operating again (CV2-2). At the time when the second dialysate chamber has finished operating, i.e., time T3, the current dialysate flow rate is calculated.

[0147] If the difference between the current dialysate flow rate and the desired dialysate flow rate is within a predetermined range, the flow rate adjustment is complete. If the difference between the current dialysate flow rate and the desired dialysate flow rate is not within the predetermined range, the correction value is calculated again. Then, the pump is controlled using the corrected pump control value. This process is repeated until the difference between the current dialysate flow rate and the desired dialysate flow rate falls within the predetermined range.

[0148] The embodiments of the present invention have been described above. The present invention is not limited to the embodiments described above, and various modifications, variations, and combinations are possible.

[0149] <1> A method for adjusting the dialysate flow rate in a personal hemodialysis machine 1 comprising a dialysate circuit 30 and a circulation pump 92 provided in the dialysate circuit 30, A pump control value determination step in which a pump control value corresponding to the desired dialysate flow rate is determined based on a calibration value that shows the correlation between the desired dialysate flow rate and the pump control value of the circulation pump, A pump operation step in which the circulation pump is operated with the pump control value determined in the pump control value determination step, A difference calculation step to determine the difference between the current dialysate flow rate and the desired dialysate flow rate, The system includes a calibration value correction step which corrects the calibration value based on the difference calculated in the difference calculation step. Method for adjusting the flow rate of dialysis fluid.

[0150] According to the above method for adjusting the dialysate flow rate, the current dialysate flow rate can be quickly adjusted to the desired flow rate.

[0151] <2> The pump control value determination step, the pump operation step, the difference calculation step, and the calibration value correction step are repeated until the difference falls within a predetermined tolerance range. <1> The method for adjusting the dialysis fluid flow rate described in [the relevant document].

[0152] According to the above method for adjusting the dialysate flow rate, the current dialysate flow rate can be brought closer to the desired dialysate flow rate.

[0153] <3> When the circulation pump is operated with the new pump control value, the difference calculation step and the calibration value correction step are executed. <1> or <2> The method for adjusting the dialysis fluid flow rate described in [reference].

[0154] According to the above method for adjusting the dialysate flow rate, when the desired dialysate flow rate is changed, the current dialysate flow rate can be quickly brought closer to the desired flow rate.

[0155] <4> The difference calculation step is performed at predetermined intervals. If the difference calculated in the difference calculation step exceeds a predetermined value, the calibration value correction step is executed. <1> from <3> A method for adjusting the dialysis fluid flow rate described in any one of the following.

[0156] According to the above method for adjusting the dialysate flow rate, it becomes possible to adjust the dialysate flow rate as needed, without requiring human monitoring of the dialysate flow rate.

[0157] <5> A personal hemodialysis device 1 comprising a dialysate circuit 30 and a circulation pump 92 provided in the dialysate circuit 30, The output of the circulation pump 92 changes according to the set pump control value. The pump control value is determined based on a calibration value that shows the correlation between the desired dialysate flow rate and the pump control value. A flow rate calculation unit 509 calculates the flow rate of the dialysate in the dialysate circuit 30, The system includes a correction value calculation unit 507 that corrects the calibration value based on the difference between the dialysate flow rate calculated by the flow rate calculation unit 509 and a desired dialysate flow rate corresponding to a set pump control value. Personal hemodialysis machine1.

[0158] According to the hemodialysis machine described above, the current dialysate flow rate can be quickly adjusted to the desired flow rate.

[0159] <6> The correction value calculation unit 507 includes a correction value adjustment unit 511. The correction value adjustment unit 511 adjusts the dialysate flow rate calculated continuously, The relationship between the calculated dialysate flow rate when the circulation pump 92 is operated with the pump control value determined based on the calibration value before correction, and the desired dialysate flow rate, When the relationship between the calculated dialysate flow rate and the desired dialysate flow rate, when the circulation pump 92 is operated with the pump control value determined based on the corrected calibration value, is reversed, In the next calibration value correction, the ratio of the correction amount to the difference between the calculated dialysate flow rate and the desired dialysate flow rate shall be smaller than the previous calibration value correction. <5> Personal hemodialysis machine 1 as described above.

[0160] According to the hemodialysis machine described above, the current dialysate flow rate can be adjusted to the desired flow rate more reliably and quickly.

[0161] <7> The correction value calculation unit 507 includes a dialysate flow rate range out-of-range determination unit 513. The dialysate flow rate range determination unit 513 determines whether the difference between the current dialysate flow rate and the desired dialysate flow rate exceeds a predetermined range. The correction value calculation unit 507 corrects the calibration value when the dialysate flow rate range out of range determination unit 513 determines that it exceeds a predetermined value. <5> or <6> Personal hemodialysis machine 1 as described above.

[0162] The hemodialysis machine described above allows for adjustment of the dialysate flow rate as needed, without requiring human monitoring of the dialysate flow rate. [Explanation of symbols]

[0163] 1 Personal hemodialysis machine 10 Dialyzer 11 Container body 20 Blood circuit 21 Arterial line 22 Venous line 23 Drug lines 24 Overflow line 30 Dialysate circuit 31 Dialysis fluid chamber 31A First Dialysis Fluid Chamber 31B Second Dialysis Fluid Chamber 32. Supply line for undiluted solution, etc. 33 Dialysis fluid infusion line 34 Dialysis fluid outlet line 35. First drainage line 36. Second drainage line 37. Water removal / back filtration pump 38 Refill fluid lines 39 Refill fluid pump 40 Heater 50 Control Unit 70 Operation section 80 Display section 90 Circulation pump line 92 Circulation pump 100 consoles 111 Blood inlet 112 Blood outlet 112d Venous clamp 113 Dialysis fluid inlet 114 Dialysate outlet 212 Blood pump 222 Venous side chamber 231 Chemical solution pump 241 Overflow Clamp 311 Container 312 Diaphragm

Claims

1. A method for adjusting the flow rate of dialysate in a hemodialysis machine comprising a dialysate circuit and a circulation pump provided in the dialysate circuit, A pump control value determination step in which a pump control value corresponding to the desired dialysate flow rate is determined based on a calibration value that shows the correlation between the desired dialysate flow rate and the pump control value of the circulation pump, A pump operation step in which the circulation pump is operated with the pump control value determined in the pump control value determination step, A difference calculation step to determine the difference between the current dialysate flow rate and the desired dialysate flow rate, The system includes a calibration value correction step which corrects the calibration value based on the difference calculated in the difference calculation step. Method for adjusting the flow rate of dialysis fluid.

2. The pump control value determination step, the pump operation step, the difference calculation step, and the calibration value correction step are repeated until the difference falls within a predetermined tolerance range. The method for adjusting the flow rate of dialysate according to claim 1.

3. When the circulation pump is operated with the new pump control value, the difference calculation step and the calibration value correction step are executed. A method for adjusting the flow rate of dialysate according to claim 1 or 2.

4. The difference calculation step is performed at predetermined intervals. If the difference calculated in the difference calculation step exceeds a predetermined value, the calibration value correction step is executed. A method for adjusting the flow rate of dialysate according to claim 1 or 2.

5. A hemodialysis apparatus comprising a dialysate circuit and a circulation pump provided in the dialysate circuit, The output of the circulation pump changes according to the set pump control value. The pump control value is determined based on a calibration value that shows the correlation between the desired dialysate flow rate and the pump control value. A flow rate calculation unit for calculating the dialysate flow rate of the dialysate circuit, The system includes a correction value calculation unit that corrects the calibration value based on the difference between the dialysate flow rate calculated by the flow rate calculation unit and a desired dialysate flow rate corresponding to a set pump control value. Hemodialysis machine.

6. The correction value calculation unit includes a correction value adjustment unit, The correction value adjustment unit, with respect to the continuously calculated dialysate flow rate, The relationship between the calculated dialysate flow rate when the circulation pump is operated with the pump control value determined based on the calibration value before correction, and the desired dialysate flow rate, When the relationship between the calculated dialysate flow rate and the desired dialysate flow rate, when the circulation pump is operated with the pump control value determined based on the corrected calibration value, is reversed, In the next calibration value correction, the ratio of the correction amount to the difference between the calculated dialysate flow rate and the desired dialysate flow rate shall be smaller than the previous calibration value correction. The hemodialysis apparatus according to claim 5.

7. The correction value calculation unit includes a dialysate flow rate range out-of-range determination unit, The dialysate flow rate range determination unit determines whether the difference between the current dialysate flow rate and the desired dialysate flow rate exceeds a predetermined range. The correction value calculation unit corrects the calibration value when the dialysate flow rate range out of range determination unit determines that it exceeds a predetermined value. The hemodialysis apparatus according to claim 5 or 6.

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