Blood purification device and method for determining detection

Abstract

The present invention is provided with: a dialysate supply flow path (52); a liquid discharge flow path (53); a supply-side control flow meter (64) and a supply-side protection flow meter (65) for detecting the flow rate of the dialysate supply flow path (52); a discharge-side control flow meter (73) and a discharge-side protection flow meter (74) that detect the flow rate of the liquid discharge flow path (53); a first water removal amount calculation unit (101) that calculates a control-side cumulative water removal amount on the basis of the flow rate detected by the supply-side control flow meter (64) and the flow rate detected by the discharge-side control flow meter (73); a second water removal amount calculation unit (102) that calculates a guard-side cumulative water removal amount on the basis of the flow rate detected by the supply-side guard flow meter (65) and the flow rate detected by the discharge-side guard flow meter (74); and a first detection failure determination unit (104) that determines the detection failure of the control flow meters (64, 73) on the basis of the difference between the control-side cumulative water removal amount and the protection-side cumulative water removal amount.

Description

Technical Field

[0001] The invention relates to a blood purification device and a method for judging poor detection of a flow meter. Background Art

[0002] As a blood purification device, two flow meters are provided on the supply side and the discharge side of the dialysate circuit, and the water removal of the blood in the dialyzer is controlled according to the two flow meters (refer to patent document 1). The blood purification device (blood treatment device) includes: a dialyzer, a supply side dialysate pipeline for supplying dialysate to the dialyzer, a first pump and a supply side flow meter (a flow sensor on the supply side) arranged in the supply side dialysate pipeline, a dialysate pipeline on the discharge side for discharging the discharge fluid from the dialyzer, and a second pump and a discharge side flow meter (a flow sensor on the discharge side) arranged in the dialysate pipeline on the discharge side. In the blood purification device, the first pump is driven according to the detection result (volume flow) of the supply side flow meter, and the second pump is driven according to the detection result (volume flow) of the discharge side flow meter, so as to control the balance between the flow rate of the supply fluid and the flow rate of the discharge fluid. Thus, the water removal of the blood in the dialyzer is controlled.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Publication No. 6752811 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] However, in conventional blood purification devices, there is a problem that each flow meter may have poor detection due to flow drift (deviation in detected flow) or failure over time, and due to this influence, errors occur in the amount of water removed.

[0008] Therefore, an object of the present invention is to provide a blood purification device and a method for determining poor detection of a flow meter, which can reduce water removal errors caused by poor detection of the flow meter.

[0009] Solutions for solving problems

[0010] A blood purification device according to one embodiment of the present invention uses a blood purifier for purifying blood to perform blood purification treatment on a patient, and the blood purification device comprises: a dialysate supply flow path, the dialysate supply flow path is used to supply dialysate to the above-mentioned blood purifier; a drainage discharge flow path, the drainage discharge flow path is used to discharge the drainage from the above-mentioned blood purifier; a first supply side flow meter, the first supply side flow meter is used to detect the flow rate of the above-mentioned dialysate supply flow path; a first discharge side flow meter, the first discharge side flow meter is used to detect the flow rate of the above-mentioned drainage discharge flow path; a first dewatering amount calculation unit, the first dewatering amount calculation unit calculates the dewatering amount according to the amount detected by the above-mentioned first supply side flow meter a second water removal amount calculation unit, which calculates the water removal amount according to the flow rate detected by the second supply side flow meter detecting the flow rate of the dialysate supply flow path and the flow rate detected by the second discharge side flow meter detecting the flow rate of the drainage discharge flow path, or calculates the theoretical water removal amount according to the target water removal speed and the treatment time; and a judgment unit, which judges whether the detection of the first supply side flow meter and the first discharge side flow meter is poor according to 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.

[0011] In addition, a method for judging poor detection of a flow meter according to one embodiment of the present invention is a method for judging poor detection of a flow meter that judges poor detection of a first supply side flow meter and a first discharge side flow meter of a blood purification device, wherein the blood purification device comprises: a dialysate supply flow path, the dialysate supply flow path being used to supply dialysate to a blood purifier for purifying blood; a drainage discharge flow path, the drainage discharge flow path being used to discharge drainage from the above-mentioned blood purifier; a first supply side flow meter, the first supply side flow meter being used to detect the flow rate of the above-mentioned dialysate supply flow path; and a first discharge side flow meter, the first discharge side flow meter being used to detect the flow rate of the above-mentioned drainage discharge flow path, wherein the following steps are performed: a first water removal amount calculation step, the first water removal amount calculation step A calculation process, in which the water removal amount is calculated 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 process, in which the water removal amount is calculated based on the flow rate detected by the second supply side flowmeter detecting the flow rate of the dialysate supply flow path and the flow rate detected by the second discharge side flowmeter detecting the flow rate of the drainage discharge flow path, or a theoretical water removal amount is calculated based on a target water removal speed and a treatment time; and a judgment process, in which the judgment process judges whether the detection of the first supply side flowmeter and the first discharge side flowmeter is poor based on the difference between the water removal amount calculated by the first water removal amount calculation process and the water removal amount calculated by the second water removal amount calculation process.

[0012] Effects of the Invention

[0013] According to an embodiment of the present invention, water removal errors caused by poor detection of a flow meter can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] [ Figure 1 ] is a schematic structural diagram showing the structure of a blood purification device according to an embodiment of the present invention.

[0015] [ Figure 2 ] represents the cumulative water removal amount on the control side, the cumulative water removal amount on the protection side and the theoretical cumulative water removal amount, and is a curve chart used to illustrate the detection failure judgment using them.

[0016] [ Figure 3 ] is a flow chart showing the detection of bad monitoring actions. DETAILED DESCRIPTION

[0017] Below, with reference to the accompanying drawings, a blood purification device and a flow meter detection poor judgment method related to an embodiment of the present invention are described. The blood purification device is a medical device for dialysis treatment, i.e., a so-called hemodialysis device, which uses a dialyzer to perform blood purification treatment on a patient. In particular, the blood purification device uses a flow meter detection poor judgment method, which can reduce the water removal error caused by the flow meter detection poor.

[0018] (Composition of blood purification device)

[0019] like Figure 1 As shown, the blood purification device 1 has: a dialyzer 10 for purifying the blood of a patient C; an extracorporeal circulation unit 11 for circulating the blood of the patient C through the dialyzer 10; and a dialysate supply and discharge device 12, which is connected to the dialyzer 10, supplies dialysate to the dialyzer 10, and discharges the effluent from the dialyzer 10. The so-called extracorporeal circulation unit 11 and the dialysate supply and discharge unit 12 are constructed in an independent manner, and the dialyzer 10 is installed on the extracorporeal circulation device 11 in a detachable manner by a fixing clamp 13. In addition, the dialyzer 10 is an example of a blood purifier.

[0020] The dialyzer 10 is equipped with a blood purification membrane (a hollow fiber type hemodialysis membrane or hemodiafiltration membrane, or a flat membrane type hemodialysis membrane or hemofiltration membrane). In addition, the dialyzer 10 has a blood inlet 10a for introducing blood and a blood outlet 10b for discharging the introduced blood, and also has a dialysate inlet 10c for introducing a dialysate and a dialysate outlet 10d for discharging the introduced dialysate. In the dialyzer 10, the blood and the dialysate are brought into contact through the blood purification membrane, thereby purifying the blood. In addition, in the dialyzer 10, by controlling the flow rate of the supply to the dialyzer 10 and the flow rate of the discharge from the dialyzer 10, the blood of the patient C can be dehydrated.

[0021] 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.

[0022] The blood circuit 21 includes an arterial blood flow path 31, a venous blood flow path 32, and a blood pump 34. The arterial blood flow path 31 is connected to the blood inlet port 10a of the dialyzer 10 to introduce blood collected from the blood vessel of the patient C into the dialyzer 10. The venous blood flow path 32 is connected to the blood outlet port 10b of the dialyzer 10 to return the blood discharged from the dialyzer 10 to the blood vessel of the patient C. The blood pump 34 is disposed on the arterial blood flow path 31 to circulate blood. By driving the blood pump 34, the blood from the patient C is introduced into the dialyzer 10 through the arterial blood flow path 31, and after the blood is purified by the dialyzer 10, it returns to the patient C through the venous blood flow path 32. In this way, the blood of the patient C is purified.

[0023] (Configuration of the Dialysate Supply and Drainage Unit)

[0024] The dialysate supply and discharge unit 12 includes a dialysate circuit 41 for supplying dialysate to the dialyzer 10 and discharging waste liquid from the dialyzer 10 , and a dialysate supply and discharge unit-side control unit 42 .

[0025] The dialysate circuit 41 comprises: a dialysate preparation unit 51 for refining the dialysate; a dialysate supply path 52 connected to the dialysate inlet 10c of the dialyzer 10 and supplying the dialysate refined by the dialysate preparation unit 51 to the dialyzer 10; and a effluent discharge path 53 connected to the dialysate discharge port 10d of the dialyzer 10 and recovering and discharging the effluent from the dialyzer 10.

[0026] The dialysate preparation unit 51 prepares the dialysate using the supplied pure water and the dialyzing agent composed of a concentrated solution or a powder. The pure water supplied to the dialysate preparation unit 51 may be supplied from a pure water production unit installed on the dialysate supply and discharge unit 12, or may be supplied from a pure water production device installed outside the dialysate supply and discharge device 12. In addition, the dialysate preparation unit 51 may also be omitted, for example, the dialysate may be supplied to the dialysate supply and discharge unit 12 from an external dialysate supply device or the like.

[0027] In the dialysate supply flow path 52, a supply pump 63, a supply-side control flow meter 64, and a supply-side protection flow meter 65 are arranged from the upstream side. 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.

[0028] The liquid supply pump 63 is a liquid supply pump that transports the dialysate in the dialysate supply flow path 52. When the liquid supply pump 63 is driven, the dialysate is supplied to the dialyzer 10.

[0029] The supply-side control flowmeter 64 and the supply-side protection flowmeter 65 are flowmeters disposed on the downstream side of the liquid supply pump 63, and are used to detect the flow rate of the dialysate supply flow path 52 (i.e., the flow rate of the liquid supply to the dialyzer 10). The supply-side control flowmeter 64 is a control flowmeter, which is used to detect the flow rate as a control quantity in the feedback control of the liquid supply pump 63. On the other hand, the supply-side protection flowmeter 65 is a protection flowmeter, which is used to ensure that the supply-side control flowmeter 64 and its detection value are normal. In addition, the "flow rate" mentioned here refers to the amount of fluid moved per unit time. In addition, 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 liquid supply pump 63.

[0030] In the waste liquid discharge flow path 53, a waste liquid pump 72, a discharge side control flow meter 73, and a discharge side protection flow meter 74 are arranged from the upstream side. The discharge side control flow meter 73 is an example of a first discharge side flow meter, and the discharge side protection flow meter 74 is an example of a second discharge side flow meter.

[0031] The drainage pump 72 is a liquid delivery pump for conveying drainage from the drainage discharge flow path 53. By driving the drainage pump 72, drainage from the dialyzer 10 is discharged. By controlling the liquid supply pump 63 and the drainage pump 72, the flow rate of the liquid supply pump 63 and the flow rate of the drainage pump 72 are controlled, thereby controlling the amount of water removed from the blood in the dialyzer 10.

[0032] The discharge side control flowmeter 73 and the discharge side protection flowmeter 74 are flowmeters disposed on the downstream side of the discharge pump 72 and used to detect the flow rate of the discharge flow path 53 (i.e., the flow rate of the discharge from the dialyzer 10). The discharge side control flowmeter 73 is a control flowmeter used to detect the flow rate as a control quantity in the feedback control of the discharge pump 72. On the other hand, the discharge side protection flowmeter 74 is a protection flowmeter used to ensure that the discharge side control flowmeter 73 and its detection value are normal. In addition, the flow rate detected by the discharge side control flowmeter 73 and the discharge side protection flowmeter 74 can also be said to be the flow rate of the discharge pump 72.

[0033] The dialysate supply and discharge unit side control unit 42 communicates with the control unit 22 of the extracorporeal circulation device 11, and controls the supply pump 63 and the discharge pump 72 according to the instruction of the control unit 22. The dialysate supply and discharge unit side control unit 42 has: a supply and discharge unit side control CPU 42a that controls the supply pump 63 and the discharge pump 72, and a supply and discharge unit side protection CPU 42b that ensures the operation of the supply and discharge unit side control CPU 42a. The supply and discharge unit side control CPU 42a and the supply and discharge unit side protection CPU 42b are respectively realized by a suitable combination of a CPU or other computing element, a memory, software, an interface, a communication unit, etc. That is, the control CPU 81 and the protection CPU 82 are configured to be separated in hardware and can operate independently.

[0034] (Description of the control unit and its control)

[0035] Now refer to Figure 1 and Figure 2 , the control unit 22 and the control of the control unit 22 are described. Figure 1 As shown, the control unit 22 includes: a control CPU 81 (so-called main control unit) for controlling various parts of the blood purification device 1; and a protection CPU 82 (so-called sub-control unit) for ensuring the operation of the control CPU 81. The control CPU 81 and the protection CPU 82 are respectively implemented by a suitable combination of a CPU or other computing element, a memory, software, an interface, a communication unit, etc. That is, the control CPU 81 and the protection CPU 82 are separated in hardware and can operate independently.

[0036] The control CPU 81 controls the driving of the blood pump 34. The control CPU 81 communicates with the supply and discharge unit side control CPU 42a, receives the detection values ​​of the supply side control flowmeter 64 and the discharge side control flowmeter 73 through the supply and discharge side control CPU 42a, and controls the liquid supply pump 63 and the liquid discharge pump 72. On the other hand, the protection CPU 82 communicates with the supply and discharge unit side protection CPU 42b, and receives the detection values ​​of the supply side protection flowmeter 65 and the discharge side protection flowmeter 74 through the supply and discharge unit side protection CPU 42b.

[0037] The control CPU 81 drives the blood pump 34, the liquid supply pump 63, and the liquid discharge pump 72 to perform dialysis treatment. That is, during the dialysis treatment, the blood pump 34 is driven to circulate blood through the dialyzer 10, the liquid supply pump 63 is driven to supply dialysate to the dialyzer 10, and the liquid discharge pump 72 is driven to discharge the liquid discharge from the dialyzer 10. During the dialysis treatment operation, the liquid supply pump 63 and the liquid discharge pump 72 are controlled to control the flow rate of the liquid supply to the dialyzer 10 (the flow rate of the dialysate supply flow path 52) and the flow rate of the liquid discharge from the dialyzer 10 (the flow rate of the liquid discharge flow path 53), thereby controlling the water removal amount of the patient C's blood. In this embodiment, the liquid supply pump 63 is driven to 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 liquid discharge pump 72 is driven to a target flow rate by feedback control using the detection value of the discharge-side control flow meter 73 as a control amount.

[0038] However, during the dialysis treatment, the control flowmeters 64 and 73 may have poor detection due to flow drift (deviation in the detected flow) caused by time changes, failures, etc. If the control flowmeters 64 and 73 have poor detection, the poor detection will affect the flow control of the dialysate supply flow path 52 and the drainage discharge flow path 53, resulting in errors in the amount of water removed from the blood. In contrast, in the blood purification device 1 of this embodiment, during the dialysis treatment operation, there is a structure for monitoring the poor detection of the control flowmeters 64 and 73. Figure 1 As shown, in the blood purification device 1, as a structure for monitoring the detection failure of the control flowmeters 64 and 73, the control CPU 81 constitutes the first water removal amount calculation unit 101, the protection CPU 82 constitutes the second water removal amount calculation unit 102, the theoretical water removal amount calculation unit 103, the first detection failure judgment unit 104, the second detection failure judgment unit 105 and the failure corresponding processing unit 106. In addition, the theoretical water removal amount calculation unit 103 is an example of the third water removal amount calculation unit, and the first detection failure judgment unit 104 and the second detection failure judgment unit 105 are examples of the judgment unit.

[0039] The first water removal amount calculation unit 101 calculates the cumulative water removal amount (hereinafter referred to as the control side cumulative water removal amount) based on the flow rate of the dialysate supply flow path 52 detected by the supply side control flow meter 64 and the flow rate of the discharge liquid discharge flow path 53 detected by the discharge side control flow meter 73. Specifically, the flow rate detected by the discharge side control flow meter 73 is subtracted from the flow rate detected by the supply side control flow meter 64 to calculate the water removal amount per unit time (flow rate difference), and the calculated water removal amounts are accumulated to calculate the control side cumulative water removal amount.

[0040] The second water removal amount calculation unit 102 calculates the cumulative water removal amount (hereinafter referred to as the protection side cumulative water removal amount) based on the flow rate of the dialysate supply flow path 52 detected by the supply side protection flow meter 65 and the flow rate of the discharge liquid discharge flow path 53 detected by the discharge side protection flow meter 74. Specifically, the flow rate detected by the discharge side protection flow meter 74 is subtracted from the flow rate detected by the supply side protection flow meter 65 to calculate the water removal amount per unit time, and the calculated water removal amounts are accumulated to calculate the protection side cumulative water removal amount.

[0041] The theoretical water removal amount calculation unit 103 calculates the theoretical cumulative water removal amount (hereinafter referred to as the theoretical cumulative water removal amount) according to the target water removal speed and the treatment time. Specifically, the theoretical cumulative water removal amount is calculated by multiplying the target water removal speed by the treatment time.

[0042] Furthermore, the cumulative water removal amount calculated by the first water removal amount calculation unit 101, the second water removal amount calculation unit 102 and the theoretical water removal amount calculation unit 103 may be the cumulative water removal amount from the start time of the treatment, which is calculated by accumulating (adding up) the water removal amount from the start time of the treatment, or the cumulative water removal amount from the start time of the interval, wherein the overall treatment time is divided into a plurality of intervals (e.g., intervals of each fixed time), and the water removal amount from the start time of each interval is accumulated (adding up). Alternatively, it may be the cumulative water removal amount of a predetermined time, wherein the water removal amount from a predetermined time before the current moment (e.g., one hour ago) to the current moment is accumulated.

[0043] The first detection failure judgment unit 104 is as follows Figure 2As shown, the first detection failure judgment of the control flowmeter 64, 73 is performed based on the difference between the control side cumulative water removal amount calculated by the first water removal amount calculation unit 101 and the protection side cumulative 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 cumulative water removal amount calculated by the first water removal amount calculation unit 101 and the protection side cumulative water removal amount calculated by the second water removal amount calculation unit 102. If it is judged that the difference is above the first threshold, it is judged that the control flowmeter 64, 73 has a serious detection failure. If it is judged that the difference is between above the second threshold value that is smaller than the first threshold value and below the first threshold value, it is judged that the control flowmeter 64, 73 has a slight detection failure. On the other hand, if it is judged that the difference is less than the second threshold value, it is judged that the control flowmeter 64, 73 has no detection failure.

[0044] The second detection failure judgment unit 105 is as follows Figure 2 As shown, based on the difference between the cumulative water removal amount on the protection side calculated by the second water removal amount calculation unit 102 and the theoretical cumulative water removal amount calculated by the theoretical water removal amount calculation unit 103, the second detection failure judgment is performed on the control flow meter 64, 73. Specifically, the second detection failure judgment unit 105 calculates the difference between the cumulative water removal amount on the protection side calculated by the second water removal amount calculation unit 102 and the theoretical cumulative water removal amount calculated by the theoretical water removal amount calculation unit 103. If it is judged that the difference is above the threshold, it is judged that the control flow meter 64, 73 has a serious detection failure. On the other hand, if it is judged that the difference is less than the threshold, it is judged that the control flow meter 64, 73 has no detection failure. In addition, the threshold of the second detection failure judgment unit 105 is preferably the same as the first threshold of the first detection failure judgment unit 104, but the threshold of the second detection failure judgment unit 105 can be a value different from the first threshold or the second threshold of the first detection failure judgment unit 104.

[0045] The poor detection corresponding processing unit 106 performs corresponding processing according to the judgment results of the first poor detection judgment unit 104 and the second poor detection judgment unit 105. Specifically, if the first poor detection judgment unit 104 or the second poor detection judgment unit 105 determines that the control flow meter 64, 73 has a serious poor detection, an alarm is output and the dialysis treatment operation is stopped. On the other hand, if the first poor detection judgment unit 104 determines that the control flow meter 64, 73 has a slight poor detection, the control flow meter 64, 73 is calibrated and the dialysis treatment operation is continued. In the calibration of the control flow meter 64, 73, for example, the correction value of the detection flow is corrected according to the difference between the cumulative water removal on the control side and the cumulative water removal on the protection side calculated by the first poor detection judgment unit 104.

[0046] (Description of monitoring actions to detect faults)

[0047] Here, refer to Figure 3 The following describes the poor detection monitoring operation of the blood purification device 1. The poor detection monitoring operation is an operation that is executed once per second by the control unit 22 during the dialysis treatment operation and determines the poor detection of the control flowmeters 64 and 73. The poor detection monitoring operation is an example of a flowmeter poor detection determination method.

[0048] like Figure 3 As shown, in the poor detection monitoring operation, the first water removal amount calculation unit 101 first calculates the control side cumulative water removal amount (S1) (first water removal amount calculation process). That is, the current water removal amount is calculated by subtracting the flow rate of the effluent discharge flow path 53 detected by the discharge side control flow meter 73 from the flow rate of the dialysate supply flow path 52 detected by the supply side control flow meter 64. Then, the calculated water removal amount is added to the water removal amount calculated by the first water removal amount calculation unit 101 in the previous poor detection monitoring operation to calculate the control side cumulative water removal amount.

[0049] Thereafter, the second water removal amount calculation unit 102 calculates the cumulative water removal amount on the protection side (S2) (second water removal amount calculation step). That is, the current water removal amount is calculated by subtracting the flow rate of the effluent discharge flow path 53 detected by the discharge side protection flow meter 74 from the flow rate of the dialysate supply flow path 52 detected by the supply side protection flow meter 65. Then, the cumulative water removal amount on the control side is calculated by adding the calculated water removal amount to the water removal amount calculated by the second water removal amount calculation unit 102 in the previous detection failure monitoring operation.

[0050] After calculating the cumulative water removal amount on the control side and the cumulative water removal amount on the protection side, the first poor detection judgment unit 104 performs a first poor detection judgment (judgment process) based on the calculated cumulative water removal amount on the control side and the cumulative water removal amount on the protection side. Specifically, it is first judged whether the difference between the cumulative water removal amount on the control side and the cumulative water removal amount on the protection side is above the first threshold value (S3). If it is judged that the difference between the cumulative water removal amount on the control side and the cumulative water removal amount on the protection side is above the first threshold value (S3: Yes), it is judged that there is a serious poor detection in the control flow meter 64, 73, and the poor detection processing unit 106 outputs an alarm (S4), stops the dialysis treatment action (S5), and terminates this poor detection monitoring action.

[0051] On the other hand, if it is determined that the difference between the control-side cumulative water removal amount and the protection-side cumulative water removal amount is not greater than the first threshold value (S3: No), it is determined whether the difference between the control-side cumulative water removal amount and the protection-side cumulative water removal amount is greater than the second threshold value (S6). If it is determined that the difference between the control-side cumulative water removal amount and the protection-side cumulative water removal amount is greater than the second threshold value (S6: Yes), it is determined that there is a slight detection failure in the control flowmeter 64, 73, and the control flowmeter 64, 73 is calibrated by the failure response processing unit 106 (S7). On the other hand, if it is determined that the difference between the control-side cumulative water removal amount and the protection-side cumulative water removal amount is not greater than the second threshold value (S6: No), the control flowmeter 64, 73 is not calibrated.

[0052] Then, the theoretical cumulative water removal amount is calculated by the theoretical water removal amount calculation unit 103 (S8). That is, the theoretical cumulative water removal amount is calculated by multiplying the target water removal speed by the treatment time.

[0053] After calculating the theoretical cumulative water removal, the second poor detection judgment unit 105 makes a second poor detection judgment based on the calculated protection side cumulative water removal and the theoretical cumulative water removal. Specifically, it is determined whether the difference between the protection side cumulative water removal and the theoretical cumulative water removal is above the threshold (S9). If it is determined that the difference between the protection side cumulative water removal and the theoretical cumulative water removal is above the threshold (S9: Yes), it is determined that there is a serious poor detection in the control flow meter 64, 73, and the poor corresponding processing unit 106 outputs an alarm (S10), stops the dialysis treatment action (S11), and terminates this poor detection monitoring action. On the other hand, if it is determined that the difference between the protection side cumulative water removal and the theoretical cumulative water removal is not above the threshold (S9: No), it is determined that there is no poor detection in the control flow meter 64, 73, and the main poor detection monitoring action is completed.

[0054] (Functions and Effects of Implementation Methods)

[0055] As described above, according to the configuration of the above embodiment, the detection failure of the control flowmeter 64, 73 is judged based on the deviation of the cumulative water removal amount, so that the detection failure accompanied by the water removal error can be appropriately judged. Accordingly, the water removal error caused by the detection failure of the control flowmeter 64, 73 can be reduced.

[0056] Furthermore, in addition to the poor detection judgment based on the difference between the cumulative water removal on the control side and the cumulative water removal on the protection side (the first poor detection judgment), the poor detection judgment based on the difference between the cumulative water removal on the protection side and the theoretical cumulative water removal can also be performed. Thus, even if the control flow meters 64, 73 and the protection flow meters 65, 74 have the same poor detection, the poor detection of the control flow meters 64, 73 can be correctly judged.

[0057] In addition to the control CPU 81, there is also a protection CPU 82, which receives the detection values ​​of the water supply side protection flow meter 65 and the drainage side protection flow meter 74, and constitutes the second water removal amount calculation unit 102 and the first detection failure judgment unit 104. Thus, even if the control CPU 81 has a detection failure cause, it can still respond.

[0058] (Variation Example)

[0059] The embodiments of the present invention have been described above, but the above embodiments are not intended to limit the inventions related to the claims. In addition, it should be noted that not all combinations of features described in the embodiments are essential to solving the problems of the present invention.

[0060] For example, in the above-mentioned embodiment, the second water removal amount calculation unit 102 calculates the cumulative water removal amount on the protection side based on the flow rate detected by the supply side protection flow meter 65 and the flow rate detected by the drainage side protection flow meter 74, and the first poor detection judgment unit 104 performs poor detection judgment based on the difference between the cumulative water removal amount on the control side and the cumulative water removal amount on the protection side. However, it is not limited to this configuration. That is, the second water removal amount calculation unit 102 can also calculate the theoretical cumulative water removal amount based on the target water removal speed and the treatment time, and the first poor detection judgment unit 104 can be configured to perform poor detection judgment based on the difference between the cumulative water removal amount on the control side and the theoretical cumulative water removal amount. In this case, in the second water removal amount calculation process (S2), the theoretical cumulative water removal amount is calculated based on the target water removal speed and the treatment time.

[0061] Furthermore, in the above-mentioned 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 cumulative water removal amounts. However, as long as the detection failure judgment is performed based on the difference between the two cumulative water removal amounts, it is not limited to this. That is, it may be a configuration in which a detection failure judgment is performed based on a subtraction value obtained by subtracting the cumulative water removal amount of one side from the cumulative water removal amount of the other side.

[0062] Furthermore, in the above-mentioned embodiment, the first water removal amount calculation unit 101, the second water removal amount calculation unit 102, and the theoretical water removal amount calculation unit 103 are configured to calculate the cumulative water removal amount, and the first poor detection judgment unit 104 and the second poor detection judgment unit 105 perform poor detection judgment based on the difference between the cumulative water removal amounts. However, this is not limited to this. That is, the first water removal amount calculation unit 101, the second water removal amount calculation unit 102, and the theoretical water removal amount calculation unit 103 calculate the water removal amount (water removal speed) per unit time, and the first poor detection judgment unit 104 and the second poor detection judgment unit 105 perform poor detection judgment based on the difference between the water removal amounts per unit time.

[0063] Furthermore, in the above-mentioned embodiment, the configuration is such that the calibration of the control flowmeters 64 and 73 is performed only when the control flowmeters 64 and 73 are judged to be slightly poorly detected, but the calibration of the control flowmeters 64 and 73 can be performed at any time. For example, the configuration can be such that the calibration of the control flowmeters 64 and 73 is performed at the start of the dialysis treatment action or when the dialysis treatment operation accompanied by an alarm is stopped. According to such a configuration, it is possible to cope with the following occasions, that is, the user can ignore the alarm and start the treatment again. Moreover, for example, it can also be performed before the poorly detected monitoring action or before the judgment (S6) of whether there is a slight poorly detected action.

[0064] Furthermore, in the above-mentioned embodiment, the following structure can be adopted, that is, in the detection failure monitoring action, a judgment is made as to whether there is a slight detection failure in the control flow meter 64, 73 (S6), and if it is judged that there is a slight detection failure in the control flow meter 64, 73, the control flow meter 64, 73 is calibrated (S7), but the following structure can also be adopted, that is, in the detection failure monitoring action, the judgment as to whether there is a slight detection failure in the control flow meter 64, 73 (S6) and the calibration (S7) of the control flow meter 64, 73 are omitted.

[0065] Furthermore, in the above-mentioned embodiment, the supply-side control flowmeter 64 and the drainage-side control flowmeter 73 are respectively the first supply-side flowmeter and the first discharge-side flowmeter, and the detection failure of the control flowmeters 64 and 73 is determined based on the difference in the amount of water removed, but the present invention is not limited to this configuration. That is, the supply-side protection flowmeter 65 and the discharge-side protection flowmeter 74 may be the first supply-side flowmeter and the first discharge-side flowmeter, and a structure in which the detection failure of the protection flowmeters 65 and 74 is determined based on the difference in the amount of water removed is also possible.

[0066] (Summary of Implementation Methods)

[0067] Next, the technical concepts grasped from the above-described embodiments will be described by referring to the symbols in the embodiments. However, the symbols in the following description are not limited to the components that specifically represent the constituent elements in the claims in the embodiments.

[0068] 《1》A blood purification device (1), which uses a blood purifier (10) for purifying blood to perform blood purification treatment on a patient (C), and the blood purification device comprises: a dialysate supply flow path (52), the dialysate supply flow path (52) being used to supply dialysate to the above-mentioned blood purifier (10); a drainage discharge flow path (53), the drainage discharge flow path (53) being used to discharge drainage from the above-mentioned blood purifier (10); a first supply side flow meter (64), the first supply side flow meter (64) being used to detect the flow rate of the above-mentioned dialysate supply flow path (52); a first discharge side flow meter (73), the first discharge side flow meter (73) being used to detect the flow rate of the above-mentioned drainage discharge flow path (53); a first dewatering amount calculation unit (101), the first dewatering amount calculation unit (101) calculating the dewatering amount according to the first supply side flow meter (6 4) and the flow rate detected by the first discharge side flow meter (73); a second water removal amount calculation unit (102), which calculates the water removal amount based on the flow rate detected by the second supply side flow meter (65) detecting the flow rate of the dialysate supply flow path (52) and the flow rate detected by the second discharge side flow meter (74) detecting the flow rate of the drainage discharge flow path (53), or calculates the theoretical water removal amount based on the target water removal speed and treatment time; and a judgment unit (104, 105), which judges whether the detection of the first supply side flow meter (64) and the first discharge side flow meter (73) is poor based on the difference between the water removal amount calculated by the first water removal amount calculation unit (101) and the water removal amount calculated by the second water removal amount calculation unit (102).

[0069] This can reduce water removal errors caused by poor detection of the flow meter.

[0070] "2" The blood purification device (1) according to "1" further has a third water removal amount calculation unit (103), which calculates the theoretical water removal amount according to the target water removal speed and the treatment time, and the second water removal amount calculation unit (102) calculates the water removal amount according to 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 whether the detection of the first supply side flow meter (64) and the first discharge side flow meter (73) is poor according to 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).

[0071] Accordingly, even if the first supply side flow meter and the first discharge side flow meter, and the second supply side flow meter and the second discharge side flow meter have the same detection failure, the detection failure of the first supply side flow meter and the first discharge side flow meter can be correctly determined.

[0072] "3" According to the blood purification device (1) described in "1" or "2", the blood purification device (1) also has: a liquid supply pump (63), which is arranged in the above-mentioned dialysate supply flow path and is used to transport the above-mentioned dialysate; a drainage pump (72), which is arranged in the above-mentioned drainage discharge flow path (53) and is used to transport the above-mentioned drainage, the above-mentioned first supply side flow meter (64) is a control flow meter, which is used to detect the above-mentioned flow rate as the control quantity in the feedback control of the above-mentioned liquid supply pump (63), the above-mentioned second supply side flow meter (65) is a protection flow meter, which is used to ensure the detection value of the above-mentioned first supply side flow meter (64), the above-mentioned first discharge side flow meter (73) is a control flow meter, which is used to detect the above-mentioned flow rate as the control quantity in the feedback control of the above-mentioned drainage pump (72), and the above-mentioned second discharge side flow meter (74) is a protection flow meter, which is used to ensure the detection value of the above-mentioned first discharge side flow meter (73).

[0073] This can reduce the water removal error caused by poor detection of the control flow meter.

[0074] "4" According to the blood purification device described in "3", the blood purification device also has: a control CPU (81), the control CPU (81) is used to control the above-mentioned liquid supply pump (63) and the above-mentioned liquid discharge pump (72); a protection CPU (82), the protection CPU (82) is used to ensure the operation of the above-mentioned control CPU, the above-mentioned control CPU (81) receives the detection values ​​of the above-mentioned first supply side flow meter (64) and the above-mentioned first discharge side flow meter (73), and constitutes the above-mentioned first water removal amount calculation unit (101), and the above-mentioned protection CPU (82) receives the detection values ​​of the above-mentioned second supply side flow meter (65) and the above-mentioned second discharge side flow meter (74), and constitutes the above-mentioned second water removal amount calculation unit (102) and the above-mentioned judgment unit (104, 105).

[0075] According to this, even when there is a cause of detection failure in the control CPU, it is possible to cope with it.

[0076] 《5》A method for judging poor detection of a flow meter (74, 64), which is a method for judging poor detection of a flow meter (74, 64) for judging poor detection of a first supply side flow meter (64) and a first discharge side flow meter (65) of a blood purification device (1), wherein the blood purification device (1) comprises: a dialysate supply flow path (52), the dialysate supply flow path (52) being used to supply dialysate to a blood purifier (10) for purifying blood; a drainage discharge flow path (53), the drainage discharge flow path (53) being used to discharge drainage from the above-mentioned blood purifier (10); a first supply side flow meter (64), the first supply side flow meter (64) being used to detect the flow rate of the above-mentioned dialysate supply flow path (52); and a first discharge side flow meter (65), the first discharge side flow meter (65) being used to detect the flow rate of the above-mentioned drainage discharge flow path (53), wherein the following steps are performed in the method: a first water removal amount calculation step (S1), the first water removal amount calculation step (S2) A first dewatering amount calculation step (S1) in which the dewatering amount is calculated 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 dewatering amount calculation step (S2) in which the dewatering amount is calculated based on the flow rate detected by the second supply side flow meter (65) detecting the flow rate of the dialysate supply flow path (52) and the flow rate detected by the second discharge side flow meter (74) detecting the flow rate of the drainage discharge flow path (53), or a theoretical dewatering amount is calculated based on a target dewatering speed and a treatment time; and a judgment step (S3, S6) in which the first supply side flow meter (64) and the first drainage side flow meter (73) are judged to have a detection failure based on the difference between the dewatering amount calculated by the first dewatering amount calculation step (S1) and the dewatering amount calculated by the second dewatering amount calculation step (S2).

[0077] This can reduce water removal errors caused by poor detection of the flow meter.

[0078] Explanation of symbols

[0079] 1: blood purification device, 10: dialyzer, 52: dialysate supply flow path, 53: drainage discharge flow path, 63: fluid 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 unit, 102: second water removal amount calculation unit, 103: theoretical water removal amount calculation unit, 104: first poor detection judgment unit, 105: second poor detection judgment unit, C: patient.

Claims

1. A blood purification device, which uses a blood purifier for purifying blood to perform blood purification treatment on a patient, and the blood purification device has: A dialysate supply flow path, the dialysate supply flow path is used to supply dialysate to the above-mentioned blood purifier; A drainage discharge flow path, the drainage discharge flow path is used to discharge the drainage from the above-mentioned blood purifier; a first supply-side flow meter, the first supply-side flow meter being used to detect the flow rate of the dialysate supply flow path; a first discharge side flow meter, the first discharge side flow meter being used to detect the flow rate of the above-mentioned 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, which calculates the water removal amount based on a flow rate detected by a second supply-side flow meter detecting a flow rate of the dialysate supply flow path and a flow rate detected by a second discharge-side flow meter detecting a flow rate of the drain discharge flow path, or calculates a theoretical water removal amount based on a target water removal rate and a treatment time; A determination unit determines that the first supply-side flow meter and the first discharge-side flow meter have detection failures based on a difference between the dewatering amount calculated by the first dewatering amount calculation unit and the dewatering amount calculated by the second dewatering amount calculation unit.

2. The blood purification device according to claim 1 further comprises a third water removal amount calculation unit, wherein the third water removal amount calculation unit calculates a theoretical water removal amount according to a target water removal speed 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 flow meter and the flow rate detected by the second discharge-side flow meter. The determination unit determines whether the first supply-side flow meter and the first discharge-side flow meter have detection failures based on a difference between the dewatering amount calculated by the second dewatering amount calculation unit and the dewatering amount calculated by the third dewatering amount calculation unit.

3. The blood purification device according to claim 1 or 2, further comprising: a liquid supply pump, the liquid supply pump being arranged in the dialysate supply flow path and being used for conveying the dialysate; and a liquid discharge pump, the liquid discharge pump being arranged in the liquid discharge flow path and used for conveying the liquid discharge, The first supply-side flow meter is a control flow meter for detecting the flow rate as a control variable in the feedback control of the liquid supply pump. The second supply side flow meter is a protective flow meter, which is used to ensure the detection value of the first supply side flow meter. The first discharge side flow meter is a control flow meter for detecting the flow rate as a control amount in the feedback control of the liquid discharge pump. The second discharge side flow meter is a protective flow meter used to ensure the detection value of the first discharge side flow meter.

4. The blood purification device according to claim 3, further comprising: a control CPU for controlling the liquid supply pump and the liquid discharge pump; and A protection CPU, which is used to ensure the operation of the control CPU. 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.

5. A method for judging poor detection of a flow meter, for judging poor detection of a first supply-side flow meter and a first discharge-side flow meter of a blood purification device, wherein the blood purification device comprises: a dialysate supply flow path for supplying dialysate to a blood purifier for purifying blood; A drainage discharge flow path, the drainage discharge flow path is used to discharge the drainage from the above-mentioned blood purifier; a first supply-side flow meter, the first supply-side flow meter being used to detect the flow rate of the dialysate supply flow path; and A first discharge side flow meter, the first discharge side flow meter is used to detect the flow rate of the above-mentioned waste liquid discharge flow path, The following steps are performed in this method: a first water removal amount calculation step, in which the water removal amount is calculated 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, in which the water removal amount is calculated based on a flow rate detected by a second supply-side flowmeter detecting a flow rate of the dialysate supply flow path and a flow rate detected by a second discharge-side flowmeter detecting a flow rate of the drain discharge flow path, or a theoretical water removal amount is calculated based on a target water removal rate and a treatment time; as well as A judging step of judging whether the first supply-side flow meter and the first discharge-side flow meter have detection failures based on a difference between the water removal amount calculated in the first water removal amount calculating step and the water removal amount calculated in the second water removal amount calculating step.

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