Blood purification device and detection failure determination method for flow meter

Abstract

To reduce a water removal error due to detection failure of a flow meter.SOLUTION: A blood purification device includes: a dialysate supply flow channel 52; a waste fluid discharge flow channel 53; a flow meter 64 for supply side control and a flow meter 65 for supply side protection for detecting a flow rate of the dialysate supply flow channel 52; a flow meter 73 for discharge side control and a flow meter 74 for discharge side protection for detecting a flow rate of the waste fluid discharge flow channel 53; a first water removal amount calculation part 101 for calculating an integrated water removal amount on the control side on the basis of the flow rate detected by the flow meter 64 for supply side control and the flow rate detected by the flow meter 73 for discharge side control; a second water removal amount calculation part 102 for calculating an integrated water removal amount on the protection side on the basis of the flow rate detected by the flow meter 65 for supply side protection and the flow rate detected by the flow meter 74 for discharge side protection; and a first detection failure determination part 104 for determining a detection failure of the flow meters 64 and 73 for control on the basis of a difference between the integrated water removal amount on the control side and the integrated water removal amount on the protection side.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a blood purification apparatus and a method for determining detection failure of a flow meter. [Background technology]

[0002] Conventionally, there is a blood purification device in which two flow meters are provided on the supply side and the discharge side of the dialysis fluid circuit, and the amount of water removed from the blood in the dialyzer is controlled by the two flow meters (see Patent Document 1). This blood purification device (blood processing device) includes a dialyzer, a supply side dialysis fluid line that supplies dialysis fluid to the dialyzer, a first pump and a supply side flow meter (supply side flow sensor) disposed in the supply side dialysis fluid line, a discharge side dialysis fluid line that discharges the waste fluid from the dialyzer, and a second pump and a discharge side flow meter (discharge side flow sensor) disposed in the discharge side dialysis fluid line. In this blood purification device, the first pump is driven based on the detection result (volumetric flow rate) of the supply side flow meter, and the second pump is driven based on the detection result (volumetric flow rate) of the discharge side flow meter, thereby controlling the balance between the flow rate of the supply fluid and the flow rate of the waste fluid. This controls the amount of water removed from the blood in the dialyzer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6752811 Summary of the Invention [Problem to be solved by the invention]

[0004] However, conventional blood purification devices had the problem that flow rate drift (deviation from detected flow rate) caused by aging or malfunctions could cause detection errors in each flow meter, which in turn caused errors in the amount of water removed.

[0005] Therefore, an object of the present invention is to provide a blood purification apparatus and a method for determining flow meter detection failure that can reduce water removal errors caused by flow meter detection failure. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the present invention provides a blood purification device which performs blood purification therapy on a patient using a blood purifier which purifies blood, the device comprising: a dialysate supply flow path which supplies dialysate to the blood purifier; a waste fluid discharge flow path which discharges waste fluid from the blood purifier; a first supply side flow meter which detects the flow rate of the dialysate supply flow path; a first discharge side flow meter which detects the flow rate of the waste fluid discharge flow path; a first water removal amount calculation unit which calculates the amount of water removed based on the flow rate detected by the first supply side flow meter and the flow rate detected by the first discharge side flow meter; Provided is a blood purification device comprising: a second water removal amount calculation unit that calculates an amount of water removed based on a flow rate detected by a second supply side flow meter that detects the flow rate in a supply flow path and a flow rate detected by a second discharge side flow meter that detects the flow rate in the drainage discharge flow path, or that calculates a theoretical amount of water removed based on a target water removal rate and treatment time; and a determination unit that determines detection failure of the first supply side flow meter and the first discharge side flow meter based on the difference between the amount of water removed calculated by the first water removal amount calculation unit and the amount of water removed calculated by the second water removal amount calculation unit.

[0007] In order to achieve the above object, the present invention provides a method for determining detection failure of the first supply-side flow meter and the first discharge-side flow meter of a blood purification device including a dialysate supply flow path that supplies dialysate to a blood purifier that purifies blood, a waste fluid discharge flow path that discharges waste fluid from the blood purifier, a first supply-side flow meter that detects a flow rate in the dialysate supply flow path, and a first discharge-side flow meter that detects a flow rate in the waste fluid discharge flow path, the method comprising: a first water removal amount calculation method for determining detection failure of the first supply-side flow meter and the first discharge-side flow meter of a blood purification device including a dialysate supply flow path that supplies dialysate to a blood purifier that purifies blood, The present invention provides a method for determining whether a flow meter is detected properly, the method comprising: a first water removal amount calculation step of calculating a water removal amount based on a flow rate detected by a second supply side flow meter that detects a flow rate in the dialysis fluid supply flow path and a flow rate detected by a second discharge side flow meter that detects a flow rate in the effluent discharge flow path, or a second water removal amount calculation step of calculating a theoretical water removal amount based on a target water removal rate and a treatment time; and a determination step of determining whether the first supply side flow meter and the first discharge side flow meter are detected properly based on the difference between the water removal amount calculated by the first water removal amount calculation step and the water removal amount calculated by the second water removal amount calculation step. Effect of the Invention

[0008] According to the present invention, it is possible to provide a blood purification apparatus and a method for determining detection failure of a flow meter, which are capable of reducing water removal errors caused by detection failure of a flow meter. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic diagram showing the structure of a blood purification device according to one embodiment of the present invention. [Diagram 2] 13 is a graph showing the control side integrated water removal amount, the protection side integrated water removal amount, and the theoretical integrated water removal amount, and explaining the detection failure judgment using these. [Diagram 3] 13 is a flowchart showing a detection failure monitoring operation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a blood purification apparatus and a method for determining a flow meter detection failure according to an embodiment of the present invention will be described with reference to the attached drawings. This blood purification apparatus is a medical device that performs dialysis treatment by administering blood purification treatment to a patient using a dialyzer, and is a so-called hemodialysis apparatus. In particular, this blood purification apparatus employs a method for determining a flow meter detection failure that can reduce water removal errors caused by a flow meter detection failure.

[0011] (Blood purification device configuration) As shown in Fig. 1, the blood purification device 1 includes a dialyzer 10 that purifies the blood of a patient C, an extracorporeal circulation unit 11 that circulates the blood of the patient C through the dialyzer 10, and a dialysate supply / drainage unit 12 that is connected to the dialyzer 10 and supplies dialysis fluid to the dialyzer 10 and discharges waste fluid from the dialyzer 10. The extracorporeal circulation unit 11 and the dialysis fluid supply / drainage unit 12 are configured separately, and the dialyzer 10 is detachably attached to the extracorporeal circulation unit 11 via a fixing jig 13. The dialyzer 10 is an example of a blood purifier.

[0012] The dialyzer 10 has a blood purification membrane (hollow fiber type hemodialysis membrane or hemodiafiltration membrane, or flat membrane type hemodialysis membrane or hemofiltration membrane) built in. The dialyzer 10 has a blood inlet 10a for introducing blood and a blood outlet 10b for discharging the introduced blood, as well as a dialysate inlet 10c for introducing dialysate and a dialysate outlet 10d for discharging the introduced dialysate. The dialyzer 10 purifies the blood by bringing the blood and the dialysate into contact with each other through the blood purification membrane. The dialyzer 10 also controls the flow rate of the supply fluid to the dialyzer 10 and the flow rate of the discharge fluid from the dialyzer 10, thereby enabling dehydration of the blood of the patient C.

[0013] The extracorporeal circulation unit 11 includes a blood circuit 21 that circulates the blood of the patient C through the dialyzer 10, and a control unit 22. The control unit 22 will be described later.

[0014] The blood circuit 21 includes an arterial blood flow path 31 connected to the blood inlet 10a of the dialyzer 10 and leading blood taken from the blood vessel of the patient C to the dialyzer 10, a venous blood flow path 32 connected to the blood outlet 10b of the dialyzer 10 and leading blood discharged from the dialyzer 10 back to the blood vessel of the patient C, and a blood pump 34 disposed in the arterial blood flow path 31 and circulating the blood. By driving the blood pump 34, blood from the patient C is led to the dialyzer 10 via the arterial blood flow path 31, and after the blood is purified by the dialyzer 10, it is returned to the patient C via the venous blood flow path 32. This purifies the blood of the patient C.

[0015] (Configuration of dialysis fluid supply and drainage unit) The dialysis fluid supply / drainage unit 12 has a dialysis fluid circuit 41 that supplies dialysis fluid to the dialyzer 10 and discharges waste fluid from the dialyzer 10, and a dialysis fluid supply / drainage unit side control unit .

[0016] The dialysis fluid circuit 41 includes a dialysis fluid preparation section 51 for purifying the dialysis fluid, a dialysis fluid supply flow path 52 connected to the dialysis fluid inlet 10c of the dialyzer 10 and for supplying the dialysis fluid purified by the dialysis fluid preparation section 51 to the dialyzer 10, and a dialysis fluid discharge flow path 53 connected to the dialysis fluid outlet 10d of the dialyzer 10 and for collecting and discharging the effluent from the dialyzer 10.

[0017] The dialysis fluid preparation section 51 prepares the dialysis fluid from the supplied pure water and a dialysate consisting of a concentrated solution or a powder. The pure water supplied to the dialysis fluid preparation section 51 may be supplied from a pure water production section mounted in the dialysis fluid supply / drainage unit 12, or may be supplied from a pure water production device provided outside the dialysis fluid supply / drainage unit 12. The dialysis fluid preparation section 51 may also be omitted, and for example, the dialysis fluid may be supplied to the dialysis fluid supply / drainage unit 12 from an external dialysis fluid supply device or the like.

[0018] In the dialysis fluid supply flow path 52, from the upstream side, a supply fluid pump 63, a supply-side control flow meter 64, and a supply-side protection flow meter 65 are disposed. The supply-side control flow meter 64 is an example of a first supply-side flow meter, and the supply-side protection flow meter 65 is an example of a second supply-side flow meter.

[0019] The supply pump 63 is a pump that sends the dialysis fluid through the dialysis fluid supply flow path 52. By driving the supply pump 63, the dialysis fluid is supplied to the dialyzer 10.

[0020] The supply-side control flowmeter 64 and the supply-side protection flowmeter 65 are disposed downstream of the supply pump 63 and detect the flow rate of the dialysis fluid supply flow path 52 (i.e., the flow rate of the supply fluid to the dialyzer 10). The supply-side control flowmeter 64 is a control flowmeter that detects the flow rate as a control amount in the feedback control of the supply pump 63. On the other hand, the supply-side protection flowmeter 65 is a protection flowmeter that ensures that the supply-side control flowmeter 64 and its detection value are normal. Note that the "flow rate" here refers to the amount of fluid moving per unit time. The flow rate detected by the supply-side control flowmeter 64 and the supply-side protection flowmeter 65 can also be said to be the flow rate of the supply pump 63.

[0021] In the waste liquid discharge flow path 53, from the upstream side, a drainage pump 72, a drainage side control flow meter 73, and a drainage side protection flow meter 74 are arranged. The drainage side control flow meter 73 is an example of a first drainage side flow meter, and the drainage side protection flow meter 74 is an example of a second drainage side flow meter.

[0022] The drainage pump 72 is a liquid sending pump that sends the drainage liquid from the drainage discharge flow path 53. By driving the drainage pump 72, the drainage liquid is discharged to the drainage from the dialyzer 10. By controlling the supply pump 63 and the drainage pump 72 to control the flow rate of the supply pump 63 and the flow rate of the drainage pump 72, the amount of water removed from the blood in the dialyzer 10 is controlled.

[0023] The discharge side control flowmeter 73 and the discharge side protection flowmeter 74 are disposed downstream of the drainage pump 72 and are flowmeters for detecting the flow rate of the drainage discharge flow path 53 (i.e., the flow rate of the drainage from the dialyzer 10). The discharge side control flowmeter 73 is a control flowmeter for detecting the flow rate as a control amount in the feedback control of the drainage pump 72. On the other hand, the discharge side protection flowmeter 74 is a protection flowmeter for ensuring that the discharge side control flowmeter 73 and its detection value are normal. The flow rates detected by the discharge side control flowmeter 73 and the discharge side protection flowmeter 74 can also be said to be the flow rates of the drainage pump 72.

[0024] The dialysis fluid supply / drainage unit side control section 42 communicates with the control section 22 of the extracorporeal circulation unit 11, and controls the supply fluid pump 63 and the drainage pump 72 according to instructions from the control section 22. The dialysis fluid supply / drainage unit side control section 42 has a supply / drainage unit side control CPU 42a that controls the supply fluid pump 63 and the drainage pump 72, and a supply / drainage unit side protection CPU 42b that ensures the operation of the supply / drainage unit side control CPU 42a. The supply / drainage unit side control CPU 42a and the supply / drainage unit side protection CPU 42b are each realized by appropriately combining a calculation element such as a CPU, a memory, software, an interface, a communication unit, and the like. That is, the control CPU 81 and the protection CPU 82 are configured such that their hardware is separated and they can operate independently.

[0025] (Explanation of the control unit and its control) Here, the control unit 22 and the control by the control unit 22 will be described with reference to Fig. 1 and Fig. 2. As shown in Fig. 1, the control unit 22 has a control CPU 81 (a so-called main control unit) that controls each unit of the blood purification apparatus 1, and a protection CPU 82 (a so-called sub-control unit) that ensures the operation of the control CPU 81. The control CPU 81 and the protection CPU 82 are each realized by appropriately combining a calculation element such as a CPU, a memory, software, an interface, a communication unit, etc. In other words, the control CPU 81 and the protection CPU 82 are configured such that their hardware is separated and they can operate independently.

[0026] The control CPU 81 controls the operation of the blood pump 34. The control CPU 81 also communicates with the supply / drain unit side control CPU 42a, receives detection values ​​of the supply side control flow meter 64 and the discharge side control flow meter 73 via the supply / drain unit side control CPU 42a, and controls the fluid supply pump 63 and the drain pump 72. On the other hand, the protection CPU 82 communicates with the supply / drain unit side protection CPU 42b, and receives detection values ​​of the supply side protection flow meter 65 and the discharge side protection flow meter 74 via the supply / drain unit side protection CPU 42b.

[0027] The control CPU 81 performs dialysis treatment by driving the blood pump 34, the supply pump 63, and the drain pump 72. That is, in dialysis treatment, the blood pump 34 is driven to circulate blood through the dialyzer 10, and the supply pump 63 is driven to supply dialysis fluid to the dialyzer 10, while the drain pump 72 is driven to discharge the drain from the dialyzer 10. During this dialysis treatment operation, the supply pump 63 and the drain pump 72 are controlled to control the flow rate of the supply fluid to the dialyzer 10 (flow rate of the dialysis fluid supply flow path 52) and the flow rate of the drain from the dialyzer 10 (flow rate of the drain discharge flow path 53), thereby controlling the amount of water removed from the blood of the patient C. In this embodiment, the supply pump 63 is driven to achieve a target flow rate by feedback control using the detection value of the supply side control flow meter 64 as a control amount, and the drain pump 72 is driven to achieve a target flow rate by feedback control using the detection value of the drain side control flow meter 73 as a control amount.

[0028] In the dialysis treatment operation, the control flow meters 64, 73 may have a detection failure due to flow rate drift (deviation of detected flow rate) caused by aging or a malfunction. When the control flow meters 64, 73 have a detection failure, the detection failure affects the flow rate control of the dialysis fluid supply flow path 52 and the waste fluid discharge flow path 53, causing an error in the amount of water removed from the blood. In response to this, the blood purification device 1 of this embodiment has a configuration for monitoring the detection failure of the control flow meters 64, 73 during the dialysis treatment operation. As shown in FIG. 1, in the blood purification device 1, the control CPU 81 constitutes a first water removal amount calculation unit 101, and the protection CPU 82 constitutes a second water removal amount calculation unit 102, a theoretical water removal amount calculation unit 103, a first detection failure determination unit 104, a second detection failure determination unit 105, and a failure response processing unit 106 as a configuration for monitoring the detection failure of the control flow meters 64, 73. The theoretical water removed amount calculation unit 103 is an example of a third water removed amount calculation unit, and the first detection failure determination unit 104 and the second detection failure determination unit 105 are an example of a determination unit.

[0029] The first water removal amount calculation unit 101 calculates an accumulated water removal amount (hereinafter referred to as a control side accumulated water removal amount) based on the flow rate of the dialysis fluid supply flow path 52 detected by the supply side control flow meter 64 and the flow rate of the waste fluid discharge flow path 53 detected by the discharge side control flow meter 73. Specifically, the first water removal amount calculation unit 101 calculates a water removal amount per unit time (flow rate difference) by subtracting the flow rate detected by the discharge side control flow meter 73 from the flow rate detected by the supply side control flow meter 64, and calculates the control side accumulated water removal amount by accumulating the calculated water removal amounts.

[0030] The second water removal amount calculation unit 102 calculates an accumulated water removal amount (hereinafter referred to as a protection side accumulated water removal amount) based on the flow rate of the dialysis fluid supply flow path 52 detected by the supply side protection flow meter 65 and the flow rate of the waste fluid discharge flow path 53 detected by the discharge side protection flow meter 74. Specifically, the second water removal amount calculation unit 102 calculates the water removal amount per unit time by subtracting the flow rate detected by the discharge side protection flow meter 74 from the flow rate detected by the supply side protection flow meter 65, and calculates the protection side accumulated water removal amount by accumulating the calculated water removal amounts.

[0031] The theoretical water removal volume calculation unit 103 calculates a theoretical integrated water removal volume (hereinafter referred to as the theoretical integrated water removal volume) based on the target water removal speed and the treatment time. Specifically, the theoretical integrated water removal volume is calculated by multiplying the target water removal speed by the treatment time.

[0032] The integrated water removal volume calculated by the first water removal volume calculation unit 101, the second water removal volume calculation unit 102, and the theoretical water removal volume calculation unit 103 may be the integrated water removal volume from the start of treatment obtained by integrating (accumulating) the amount of water removed from the start of treatment, or may be the integrated water removal volume from the start of each section obtained by dividing the entire treatment time into a plurality of sections (for example, sections at regular intervals) and integrating (accumulating) the amount of water removed from the start of each section. Alternatively, it may be the integrated water removal volume for a predetermined time obtained by integrating the amount of water removed from a predetermined time before the current time (for example, one hour before) to the current time.

[0033] As shown in FIG. 2, the first detection failure judgment unit 104 performs a first detection failure judgment of the control flow meter 64, 73 based on the difference between the control side integrated water removal amount calculated by the first water removal amount calculation unit 101 and the protection side integrated water removal amount calculated by the second water removal amount calculation unit 102. Specifically, the first detection failure judgment unit 104 calculates the difference between the control side integrated water removal amount calculated by the first water removal amount calculation unit 101 and the protection side integrated water removal amount calculated by the second water removal amount calculation unit 102, and if it is determined that the difference is equal to or greater than a first threshold, it judges that the control flow meter 64, 73 has a severe detection failure. If it is determined that the difference is equal to or greater than a second threshold smaller than the first threshold and less than the first threshold, it judges that the control flow meter 64, 73 has a mild detection failure. On the other hand, if it is determined that the difference is less than the second threshold, it judges that the control flow meter 64, 73 does not have a detection failure.

[0034] As shown in Fig. 2, the second detection failure judgment unit 105 performs a second detection failure judgment of the control flow meters 64, 73 based on the difference between the protection side accumulated water removal amount calculated by the second water removal amount calculation unit 102 and the theoretical accumulated water removal amount calculated by the theoretical water removal amount calculation unit 103. Specifically, the second detection failure judgment unit 105 calculates the difference between the protection side accumulated water removal amount calculated by the second water removal amount calculation unit 102 and the theoretical accumulated water removal amount calculated by the theoretical water removal amount calculation unit 103, and if it is determined that the difference is equal to or greater than a threshold value, it judges that the control flow meters 64, 73 have a severe detection failure. On the other hand, if it is determined that the difference is less than the threshold value, it judges that the control flow meters 64, 73 do not have a detection failure. It is preferable that the threshold value of the second detection failure judgment unit 105 is the same as the first threshold value of the first detection failure judgment unit 104, but the threshold value of the second detection failure judgment unit 105 may be a value different from the first threshold value and the second threshold value of the first detection failure judgment unit 104.

[0035] The failure response processing unit 106 executes a response process based on the judgment results of the first detection failure judgment unit 104 and the second detection failure judgment unit 105. Specifically, when the first detection failure judgment unit 104 or the second detection failure judgment unit 105 judges that the control flow meters 64, 73 have a severe detection failure, it outputs an alarm and stops the dialysis treatment operation. On the other hand, when the first detection failure judgment unit 104 judges that the control flow meters 64, 73 have a mild detection failure, it calibrates the control flow meters 64, 73 and continues the dialysis treatment operation. In calibrating the control flow meters 64, 73, for example, a correction value of the detected flow rate is corrected based on the difference between the control side integrated water removal amount and the protection side integrated water removal amount calculated by the first detection failure judgment unit 104.

[0036] (Description of detection failure monitoring operation) 3, the detection failure monitoring operation by the blood purification apparatus 1 will be described. This detection failure monitoring operation is executed by the control unit 22 every second during dialysis treatment operation, and is an operation for determining detection failure of the control flow meters 64, 73. The detection failure monitoring operation is an example of a method for determining detection failure of the flow meters.

[0037] As shown in Fig. 3, in the detection failure monitoring operation, first, the first water removal amount calculation unit 101 calculates the control side accumulated water removal amount (S1) (first water removal amount calculation step). That is, the flow rate of the effluent discharge flow path 53 detected by the discharge side control flow meter 73 is subtracted from the flow rate of the dialysis fluid supply flow path 52 detected by the supply side control flow meter 64 to calculate the current water removal amount. Then, the calculated water removal amount is integrated with the water removal amount calculated by the first water removal amount calculation unit 101 in the detection failure monitoring operation up to the previous time to calculate the control side accumulated water removal amount.

[0038] Thereafter, the second water removal amount calculation unit 102 calculates the protection side accumulated water removal amount (S2) (second water removal amount calculation step). That is, the flow rate of the waste fluid discharge flow path 53 detected by the discharge side protection flow meter 74 is subtracted from the flow rate of the dialysis fluid supply flow path 52 detected by the supply side protection flow meter 65 to calculate the current water removal amount. Then, the calculated water removal amount and the water removal amount calculated by the second water removal amount calculation unit 102 in the previous detection failure monitoring operation are integrated to calculate the control side accumulated water removal amount.

[0039] After the control side integrated water removal volume and the protection side integrated water removal volume are calculated, the first detection failure judgment unit 104 performs a first detection failure judgment based on the calculated control side integrated water removal volume and protection side integrated water removal volume (judgment step). Specifically, first, it is judged whether the difference between the control side integrated water removal volume and the protection side integrated water removal volume is equal to or greater than a first threshold value (S3). If it is judged that the difference between the control side integrated water removal volume and the protection side integrated water removal volume is equal to or greater than the first threshold value (S3: Yes), it is judged that there is a serious detection failure in the control flowmeters 64, 73, and the failure response processing unit 106 outputs an alarm (S4), stops the dialysis treatment operation (S5), and ends this detection failure monitoring operation.

[0040] On the other hand, if it is determined that the difference between the control side integrated water removal amount and the protection side integrated water removal amount is not equal to or greater than the first threshold (S3: No), it is determined whether or not the difference between the control side integrated water removal amount and the protection side integrated water removal amount is equal to or greater than the second threshold (S6). If it is determined that the difference between the control side integrated water removal amount and the protection side integrated water removal amount is equal to or greater than the second threshold (S6: Yes), it is determined that the control flow meters 64, 73 have a minor detection failure, and the failure response processing unit 106 calibrates the control flow meters 64, 73 (S7). On the other hand, if it is determined that the difference between the control side integrated water removal amount and the protection side integrated water removal amount is not equal to or greater than the second threshold (S6: No), the control flow meters 64, 73 are not calibrated.

[0041] Thereafter, the theoretical integrated water removal volume is calculated by the theoretical water removal volume calculation unit 103 (S8). That is, the theoretical integrated water removal volume is calculated by multiplying the target water removal speed by the treatment time.

[0042] After the theoretical integrated water removal volume is calculated, the second detection failure judgment unit 105 performs a second detection failure judgment based on the calculated protection side integrated water removal volume and theoretical integrated water removal volume. Specifically, it is judged whether the difference between the protection side integrated water removal volume and the theoretical integrated water removal volume is equal to or greater than a threshold value (S9). If it is judged that the difference between the protection side integrated water removal volume and the theoretical integrated water removal volume is equal to or greater than a threshold value (S9: Yes), it is judged that the control flow meters 64, 73 have a serious detection failure, and the failure response processing unit 106 outputs an alarm (S10) and stops the dialysis treatment operation (S11), and ends this detection failure monitoring operation. On the other hand, if it is judged that the difference between the protection side integrated water removal volume and the theoretical integrated water removal volume is not equal to or greater than the threshold value (S9: No), it is judged that the control flow meters 64, 73 do not have a detection failure, and ends this detection failure monitoring operation.

[0043] (Actions and Effects of the Embodiments) As described above, according to the configuration of the above embodiment, since the detection failure of the control flow meters 64, 73 is judged based on the deviation of the integrated water removal amount, the detection failure accompanied by the water removal error can be appropriately judged. As a result, the water removal error due to the detection failure of the control flow meters 64, 73 can be reduced.

[0044] In addition to the detection failure judgment (first detection failure judgment) based on the difference between the control side accumulated water removal volume and the protection side accumulated water removal volume, a detection failure judgment (second detection failure judgment) is also made based on the difference between the protection side accumulated water removal volume and the theoretical accumulated water removal volume, so that even if a similar detection failure occurs in the control flow meters 64, 73 and the protection flow meters 65, 74, the detection failure of the control flow meters 64, 73 can be accurately judged.

[0045] In addition to the control CPU 81, a protection CPU 82 is provided, which receives the detection values ​​of the supply side protection flow meter 65 and the discharge side protection flow meter 74, and also constitutes a second water removal volume calculation unit 102 and a first detection failure judgment unit 104, so that if the control CPU 81 is the cause of the detection failure, it can respond to this.

[0046] (Modification) Although the embodiments of the present invention have been described above, the invention according to the claims is not limited to the above-described embodiments. It should be noted that not all of the combinations of features described in the embodiments are essential to the means for solving the problems of the invention.

[0047] For example, in the above embodiment, the second water removal amount calculation unit 102 calculates the protection side integrated water removal amount based on the flow rate detected by the supply side protection flow meter 65 and the flow rate detected by the discharge side protection flow meter 74, and the first detection failure judgment unit 104 judges the detection failure based on the difference between the control side integrated water removal amount and the protection side integrated water removal amount, but this is not limited to the above. That is, the second water removal amount calculation unit 102 may calculate the theoretical integrated water removal amount based on the target water removal speed and the treatment time, and the first detection failure judgment unit 104 may judge the detection failure based on the difference between the control side integrated water removal amount and the theoretical integrated water removal amount. In this case, in the second water removal amount calculation step (S2), the theoretical integrated water removal amount is calculated based on the target water removal speed and the treatment time.

[0048] In the above embodiment, the first detection failure judgment unit 104 and the second detection failure judgment unit 105 are configured to perform a detection failure judgment based on the difference between the two integrated water removal amounts, but the present invention is not limited to this configuration as long as the detection failure judgment is performed based on the difference between the two integrated water removal amounts. That is, the detection failure judgment may be performed based on a subtraction value obtained by subtracting one integrated water removal amount from the other integrated water removal amount.

[0049] In the above embodiment, the first water removed amount calculation unit 101, the second water removed amount calculation unit 102, and the theoretical water removed amount calculation unit 103 calculate the accumulated amount of water removed, and the first detection failure judgment unit 104 and the second detection failure judgment unit 105 judge whether or not the detection is defective based on the difference between the accumulated amounts of water removed, but the present invention is not limited to this. That is, the first water removed amount calculation unit 101, the second water removed amount calculation unit 102, and the theoretical water removed amount calculation unit 103 may calculate the amount of water removed per unit time (water removal speed), and the first detection failure judgment unit 104 and the second detection failure judgment unit 105 may judge whether or not the detection is defective based on the difference between the amount of water removed per unit time.

[0050] In the above embodiment, the control flow meters 64, 73 are calibrated only when it is determined that the control flow meters 64, 73 have a minor detection failure. However, the control flow meters 64, 73 can be calibrated at any timing. For example, the control flow meters 64, 73 may be calibrated at the start of a dialysis treatment operation or at the stop of a dialysis treatment operation accompanied by an alarm. This configuration can also handle the case where a user ignores the alarm and resumes treatment. For example, the control flow meters 64, 73 may be calibrated before the detection failure monitoring operation or before determining whether or not there is a minor detection failure (S6).

[0051] In addition, in the above embodiment, in the detection failure monitoring operation, a determination is made (S6) as to whether or not the control flow meters 64, 73 have a minor detection failure, and if it is determined that the control flow meters 64, 73 have a minor detection failure, the control flow meters 64, 73 are calibrated (S7). However, in the detection failure monitoring operation, the determination as to whether or not the control flow meters 64, 73 have a minor detection failure (S6) and the calibration of the control flow meters 64, 73 (S7) may be omitted.

[0052] In the above embodiment, the supply-side control flow meter 64 and the discharge-side control flow meter 73 are configured as a first supply-side flow meter and a first discharge-side flow meter, and detection failure of the control flow meters 64, 73 is determined based on the difference in the amount of water removed, but the present invention is not limited to this. That is, the supply-side protection flow meter 65 and the discharge-side protection flow meter 74 may be configured as a first supply-side flow meter and a first discharge-side flow meter, and detection failure of the protection flow meters 65, 74 may be determined based on the difference in the amount of water removed.

[0053] (Summary of the embodiment) Next, the technical ideas understood from the above-described embodiments will be described by using the reference numerals and the like in the embodiments. However, the reference numerals and the like in the following description do not limit the components in the claims to the members and the like specifically shown in the embodiments.

[0054] 1. A blood purification device (1) for performing blood purification therapy on a patient (C) using a blood purifier (10) for purifying blood, comprising: a dialysate supply flow path (52) for supplying a dialysate to the blood purifier (10); a waste fluid discharge flow path (53) for discharging a waste fluid from the blood purifier (10); a first supply-side flow meter (64) for detecting a flow rate in the dialysate supply flow path (52); a first discharge-side flow meter (73) for detecting a flow rate in the waste fluid discharge flow path (53); a first water removal amount calculation unit (101) for calculating a water removal amount based on the flow rate detected by the first supply-side flow meter (64) and the flow rate detected by the first discharge-side flow meter (73); a second water removal amount calculation unit (102) that calculates an amount of water removed based on a flow rate detected by a second supply side flow meter (65) that detects a flow rate in the drainage discharge flow path (52) and a flow rate detected by a second discharge side flow meter (74) that detects a flow rate in the drainage discharge flow path (53), or that calculates a theoretical amount of water removed based on a target water removal rate and a treatment time; and a determination unit (104, 105) that determines detection failure of the first supply side flow meter (64) and the first discharge side flow meter (73) based on the difference between the amount of water removed calculated by the first water removal amount calculation unit (101) and the amount of water removed calculated by the second water removal amount calculation unit (102). This makes it possible to reduce water removal errors caused by detection errors of the flow meter. The blood purification device (1) described in <<1>> further includes a third water removal amount calculation unit (103) that calculates a theoretical water removal amount based on a target water removal rate and treatment time, wherein the second water removal amount calculation unit (102) calculates the water removal amount based on the flow rate detected by the second supply side flow meter (65) and the flow rate detected by the second discharge side flow meter (74), and the judgment unit (104, 105) judges detection failure of the first supply side flow meter (64) and the first discharge side flow meter (73) based on the difference between the water removal amount calculated by the second water removal amount calculation unit (102) and the water removal amount calculated by the third water removal amount calculation unit (103). This makes it possible to accurately determine the detection failure of the first supply side flow meter and the first discharge side flow meter, and the detection failure of the second supply side flow meter and the second discharge side flow meter, even if similar detection failure occurs in the first supply side flow meter and the first discharge side flow meter. <3> The blood purification device (1) according to <1> or <2>, further comprising: a supply pump (63) arranged in the dialysis fluid supply flow path (52) for supplying the dialysis fluid; and a drainage pump (72) arranged in the drainage discharge flow path (53) for supplying the drainage fluid, wherein the first supply-side flow meter (64) is a control flow meter that detects the flow rate as a control variable in feedback control of the supply pump (63), the second supply-side flow meter (65) is a protection flow meter that guarantees the detection value of the first supply-side flow meter (64), the first drainage side flow meter (73) is a control flow meter that detects the flow rate as a control variable in feedback control of the drainage pump (72), and the second drainage side flow meter (74) is a protection flow meter that guarantees the detection value of the first drainage side flow meter (73). This makes it possible to reduce water removal errors caused by detection errors of the control flow meter. <4> The blood purification apparatus (1) described in <3>, further comprising a control CPU (81) that controls the supply pump (63) and the drainage pump (72), and a protection CPU (82) that ensures operation of the control CPU (81), wherein the control CPU (81) receives detection values ​​of the first supply side flow meter (64) and the first discharge side flow meter (73) and constitutes the first water removal amount calculation unit (101), and the protection CPU (82) receives detection values ​​of the second supply side flow meter (65) and the second discharge side flow meter (74), and constitutes the second water removal amount calculation unit (102) and the determination unit (104, 105). This makes it possible to deal with any detection failures that may be caused by the control CPU. <5> A method for determining detection failure of flow meters (74, 64) for determining detection failure of the first supply-side flow meter (64) and the first discharge-side flow meter (65) of a blood purification apparatus (1) including a dialysate supply flow path (52) for supplying dialysate to a blood purifier (10) that purifies blood, a waste fluid discharge flow path (53) for discharging waste fluid from the blood purifier (10), a first supply-side flow meter (64) for detecting a flow rate in the dialysate supply flow path (52), and a first discharge-side flow meter (65) for detecting a flow rate in the waste fluid discharge flow path (53), the method including a first water removal amount calculation step (S 2 ) for calculating a water removal amount based on the flow rate detected by the first supply-side flow meter (64) and the flow rate detected by the first discharge-side flow meter (73), a second water removal amount calculation step (S2) of calculating an amount of water removed based on a flow rate detected by a second supply-side flow meter (65) that detects a flow rate in the dialysis fluid supply flow path (52) and a flow rate detected by a second discharge-side flow meter (74) that detects a flow rate in the waste fluid discharge flow path (53), or calculating a theoretical amount of water removed based on a target water removal rate and a treatment time; and determination steps (S3, S6) of determining whether or not there is a detection failure of the first supply-side flow meter (64) and the first discharge-side flow meter (73) based on a difference between the amount of water removed calculated in the first water removal amount calculation step (S1) and the amount of water removed calculated in the second water removal amount calculation step (S2). This makes it possible to reduce water removal errors caused by detection errors of the flow meter. [Explanation of symbols]

[0055] 1: blood purification device, 10: dialyzer, 52: dialysis fluid supply flow path, 53: waste fluid discharge flow path, 63: supply pump, 64: supply side control flow meter, 65: supply side protection flow meter, 72: drainage pump, 73: discharge side control flow meter, 74: discharge side protection flow meter, 81: control CPU, 82: protection CPU, 101: first water removal amount calculation section, 102: second water removal amount calculation section, 103: theoretical water removal amount calculation section, 104: first detection failure judgment section, 105: second detection failure judgment section, C: patient

Claims

1. A blood purification apparatus for performing blood purification treatment on a patient using a blood purifier for purifying blood, a dialysate supply passage for supplying dialysate to the blood purifier, a drainage discharge passage for discharging drainage from the blood purifier, a first supply-side flowmeter for detecting the flow rate of the dialysate supply passage, a first discharge-side flowmeter for detecting the flow rate of the drainage discharge passage, a first water removal amount calculation unit for calculating the water removal amount based on the flow rate detected by the first supply-side flowmeter and the flow rate detected by the first discharge-side flowmeter, a second water removal amount calculation unit for calculating the water removal amount based on the flow rate detected by a second supply-side flowmeter for detecting the flow rate of the dialysate supply passage and the flow rate detected by a second discharge-side flowmeter for detecting the flow rate of the drainage discharge passage, or for calculating a theoretical water removal amount based on a target water removal rate and a treatment time, a determination unit for determining a detection failure of the first supply-side flowmeter and the first discharge-side flowmeter based on a difference between the water removal amount calculated by the first water removal amount calculation unit and the water removal amount calculated by the second water removal amount calculation unit, A blood purification apparatus.

2. further comprising a third water removal amount calculation unit for calculating a theoretical water removal amount based on a target water removal rate and a treatment time, the second water removal amount calculation unit calculates the water removal amount based on the flow rate detected by the second supply-side flowmeter and the flow rate detected by the second discharge-side flowmeter, the determination unit determines a detection failure of the first supply-side flowmeter and the first discharge-side flowmeter based on a difference between the water removal amount calculated by the second water removal amount calculation unit and the water removal amount calculated by the third water removal amount calculation unit, The blood purification apparatus according to claim 1.

3. a liquid supply pump disposed in the dialysate supply passage for feeding the dialysate, a drainage pump disposed in the drainage discharge passage for feeding the drainage, the first supply-side flowmeter is a flowmeter for control that detects the flow rate as a control amount in the feedback control of the liquid supply pump, the second supply-side flowmeter is a protective flowmeter for ensuring the detection value of the first supply-side flowmeter, the first discharge-side flowmeter is a flowmeter for control that detects the flow rate as a control amount in the feedback control of the drainage pump, the second discharge-side flowmeter is a protective flowmeter for ensuring the detection value of the first discharge-side flowmeter, The blood purification apparatus according to claim 1 or 2.

4. A control CPU that controls the liquid supply pump and the liquid discharge pump; A protection CPU for ensuring the operation of the control CPU, and further includes; The control CPU receives the detection values of the first supply-side flow meter and the first discharge-side flow meter, and constitutes the first water removal amount calculation unit; The protection CPU receives the detection values of the second supply-side flow meter and the second discharge-side flow meter, and constitutes the second water removal amount calculation unit and the determination unit; The blood purification device according to claim 3.

5. A blood purification device that performs blood purification treatment on a patient using a blood purifier that purifies blood, A dialysate supply flow path that supplies dialysate to the blood purifier; A drainage discharge flow path that discharges the drainage from the blood purifier; A first supply-side flow meter that detects the flow rate of the dialysate supply flow path; A first discharge-side flow meter that detects the flow rate of the drainage discharge flow path; A first water removal amount calculation unit that calculates the water removal amount based on the flow rate detected by the first supply-side flow meter and the flow rate detected by the first discharge-side flow meter; A second water removal amount calculation unit that calculates the water removal amount based on the flow rate detected by the second supply-side flow meter that detects the flow rate of the dialysate supply flow path and the flow rate detected by the second discharge-side flow meter that detects the flow rate of the drainage discharge flow path; A determination unit that determines a detection failure of the first supply-side flow meter and the first discharge-side flow meter based on the difference between the water removal amount calculated by the first water removal amount calculation unit and the water removal amount calculated by the second water removal amount calculation unit; Blood purification device.

6. A blood purification device that performs blood purification treatment on a patient using a blood purifier that purifies blood, A dialysate supply flow path that supplies dialysate to the blood purifier; A drainage discharge flow path that discharges the drainage from the blood purifier; A first supply-side flow meter that detects the flow rate of the dialysate supply flow path; A first discharge-side flow meter that detects the flow rate of the drainage discharge flow path; A first water removal amount calculation unit that calculates the water removal amount based on the flow rate detected by the first supply-side flow meter and the flow rate detected by the first discharge-side flow meter; A second water removal amount calculation unit that calculates the water removal amount based on the flow rate detected by the second supply-side flow meter that detects the flow rate of the dialysate supply flow path and the flow rate detected by the second discharge-side flow meter that detects the flow rate of the drainage discharge flow path; A determination unit that determines a detection failure of the first supply-side flowmeter and the first discharge-side flowmeter based on the difference between the water removal amount calculated by the first water removal amount calculation unit and the water removal amount calculated by the second water removal amount calculation unit; A third water removal amount calculation unit that calculates a theoretical water removal amount based on a target water removal rate and a treatment time; The determination unit determines a detection failure of the first supply-side flowmeter and the first discharge-side flowmeter based on the difference between the water removal amount calculated by the second water removal amount calculation unit and the water removal amount calculated by the third water removal amount calculation unit. Blood purification device.

7. A blood purification device that performs blood purification treatment on a patient using a blood purifier that purifies blood, A dialysate supply channel that supplies dialysate to the blood purifier; A drainage discharge channel that discharges the drainage from the blood purifier; A first supply-side flowmeter that detects the flow rate of the dialysate supply channel; A first discharge-side flowmeter that detects the flow rate of the drainage discharge channel; A first water removal amount calculation unit that calculates a water removal amount based on the flow rate detected by the first supply-side flowmeter and the flow rate detected by the first discharge-side flowmeter; A second water removal amount calculation unit that calculates a water removal amount based on the flow rate detected by a second supply-side flowmeter that detects the flow rate of the dialysate supply channel and the flow rate detected by a second discharge-side flowmeter that detects the flow rate of the drainage discharge channel, or calculates a theoretical water removal amount based on a target water removal rate and a treatment time; A determination unit that determines a detection failure of the first supply-side flowmeter and the first discharge-side flowmeter based on the difference between the water removal amount calculated by the first water removal amount calculation unit and the water removal amount calculated by the second water removal amount calculation unit; A liquid supply pump disposed in the dialysate supply channel for sending the dialysate; A drainage pump disposed in the drainage discharge channel for sending the drainage; The first supply-side flowmeter is a flowmeter for control that detects the flow rate as a control amount in the feedback control of the liquid supply pump; The second supply-side flowmeter is a protective flowmeter for guaranteeing the detection value of the first supply-side flowmeter; The first discharge-side flowmeter is a flowmeter for control that detects the flow rate as a control amount in the feedback control of the drainage pump; The second discharge-side flowmeter is a protective flowmeter for guaranteeing the detection value of the first discharge-side flowmeter. Blood purification device.

8. A method for determining a detection failure of a flow meter for a blood purification device including a dialysate supply channel that supplies dialysate to a blood purifier for purifying blood, a drainage discharge channel that discharges drainage from the blood purifier, a first supply-side flow meter that detects the flow rate of the dialysate supply channel, and a first discharge-side flow meter that detects the flow rate of the drainage discharge channel, the method comprising: a first water removal amount calculation step of calculating a water removal amount based on the flow rate detected by the first supply-side flow meter and the flow rate detected by the first discharge-side flow meter; a second water removal amount calculation step of calculating a water removal amount based on the flow rate detected by a second supply-side flow meter that detects the flow rate of the dialysate supply channel and the flow rate detected by a second discharge-side flow meter that detects the flow rate of the drainage discharge channel, or calculating a theoretical water removal amount based on a target water removal rate and a treatment time; a determination step of determining a detection failure of the first supply-side flow meter and the first discharge-side flow meter based on the difference between the water removal amount calculated in the first water removal amount calculation step and the water removal amount calculated in the second water removal amount calculation step; A method for determining a detection failure of a flow meter.

9. A method for determining a detection failure of a flow meter for a blood purification device including a dialysate supply channel that supplies dialysate to a blood purifier for purifying blood, a drainage discharge channel that discharges drainage from the blood purifier, a first supply-side flow meter that detects the flow rate of the dialysate supply channel, and a first discharge-side flow meter that detects the flow rate of the drainage discharge channel, the method comprising: a first water removal amount calculation step of calculating a water removal amount based on the flow rate detected by the first supply-side flow meter and the flow rate detected by the first discharge-side flow meter; a second water removal amount calculation step of calculating a water removal amount based on the flow rate detected by a second supply-side flow meter that detects the flow rate of the dialysate supply channel and the flow rate detected by a second discharge-side flow meter that detects the flow rate of the drainage discharge channel; a determination step of determining a detection failure of the first supply-side flow meter and the first discharge-side flow meter based on the difference between the water removal amount calculated in the first water removal amount calculation step and the water removal amount calculated in the second water removal amount calculation step; A method for determining a detection failure of a flow meter. A method for determining a detection failure of a flow meter for determining a detection failure of a first supply-side flow meter that detects the flow rate of a dialysis fluid supply passage that supplies dialysis fluid to a blood purifier that purifies blood, a drainage discharge passage that discharges drainage from the blood purifier, and the first discharge-side flow meter that detects the flow rate of the drainage discharge passage, in a blood purification apparatus including: a first water removal amount calculation step of calculating a water removal amount based on the flow rate detected by the first supply-side flow meter and the flow rate detected by the first discharge-side flow meter; a second water removal amount calculation step of calculating a water removal amount based on the flow rate detected by a second supply-side flow meter that detects the flow rate of the dialysis fluid supply passage and the flow rate detected by a second discharge-side flow meter that detects the flow rate of the drainage discharge passage; a determination step of determining a detection failure of the first supply-side flow meter and the first discharge-side flow meter based on a difference between the water removal amount calculated in the first water removal amount calculation step and the water removal amount calculated in the second water removal amount calculation step; a third water removal amount calculation step of calculating a theoretical water removal amount based on a target water removal rate and a treatment time, and in the determination step, a detection failure of the first supply-side flow meter and the first discharge-side flow meter is determined based on a difference between the water removal amount calculated in the second water removal amount calculation step and the water removal amount calculated in the third water removal amount calculation step. A method for determining a detection failure of a flow meter.

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