Blood purification device

Abstract

Provided is a blood purification device in which blood remaining in a blood circuit can be smoothly returned to the body of a patient without reconnecting a line for supplying a replacement liquid during blood return, even if a blood flow path is blocked or narrowed during blood return. A blood purification device is provided with: a physiological saline supply line (La) that is connected to a position upstream of a blood extraction-side blood circuit (1a) and that supplies a replacement liquid to the blood circuit (1) when blood returns; a pre-replacement line (L2c) and a post-replacement line (L2d), which are connected downstream of the blood circuit (1) at a different downstream position from the upstream position, for supplying the replacement liquid to the blood circuit (1) when the blood is returned; a occlusion recognition unit (7) configured to recognize any occlusion position of the blood flow path in the blood circuit (1) or the dialyzer (2) on the basis of the pressure detected by the pressure detection units (S1-S3); and a control unit (11) that, when the occlusion recognition unit (7) recognizes the occlusion position, switches from one of the blood extraction-side replacement liquid supply line and the blood return-side replacement liquid supply line to the other at the time of blood return.

Description

Technical Field

[0001] The present invention relates to a blood purification device for purifying a patient's blood while causing the blood to perform extracorporeal circulation. Background Art

[0002] In general, a blood purification device for performing dialysis treatment includes: a blood circuit on the blood extraction side and a blood circuit on the blood return side that form a blood circuit for extracorporeal circulation of the patient's blood; a blood purifier for purifying the blood circulated extracorporeally in the blood circuit; and a device body provided with various components such as a blood pump for performing blood purification treatment through the blood circuit and the blood purifier. The blood circuit on the blood extraction side and the blood return side are respectively provided with a vascular access catheter or a puncture needle (a blood extraction side puncture needle or a blood return side puncture needle) that can be installed at their distal ends.

[0003] For example, after puncturing the patient with a blood extraction side puncture needle and a blood return side puncture needle, the blood pump is started. In this way, the patient's blood circulates in vitro through the blood extraction side blood circuit and the blood return side blood circuit. In this process, the blood is purified by the blood purifier. After the blood purification treatment is completed, blood return is usually performed to return the remaining blood in the blood circuit to the patient. For example, as disclosed in Patent Document 1, blood return is a process of pushing the remaining blood in the blood circuit back into the patient's body by supplying a replacement fluid (e.g., saline) to the blood circuit.

[0004] Citation list

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2009-131412. Summary of the invention

[0007] Problem that the invention aims to solve

[0008] In existing blood purification devices, if the blood flow path in the blood circuit (especially the blood circuit on the blood extraction side) is blocked or narrowed due to blood coagulation, the blood and replacement fluid will not flow when the blood pump is started during blood return, resulting in difficulty in blood return. In this case, it is necessary to stop the blood return and dispose of the remaining blood together with the blood circuit; or, it is necessary to reconnect the pipeline supplying the replacement fluid to the downstream position of the blocked position in order to continue the blood return.

[0009] The present invention has been completed in view of the above situation, and its purpose is to provide a blood purification device that can smoothly return the blood remaining in the blood circuit to the patient's body even if the blood flow path is blocked or narrowed when the blood returns, and there is no need to reconnect the pipeline for supplying replacement fluid when the blood returns.

[0010] Solutions to the problem

[0011] A blood purification device according to an embodiment of the present invention includes: a blood circuit, which includes a blood circuit on the blood extraction side for extracting blood from a patient and a blood circuit on the blood return side for returning blood to the patient, wherein the patient's blood circulates extracorporeally through the blood circuit, a blood purifier is connected to the blood circuit on the blood extraction side and the blood circuit on the blood return side, and the blood purifier is configured to purify blood; a blood pump, which is arranged in the blood circuit and configured to cause the patient's blood to perform extracorporeal circulation through the blood circuit; a replacement fluid supply line on the blood extraction side, which is connected to the blood circuit, and when the blood returns, the replacement fluid is supplied to the blood circuit through the blood extraction side replacement fluid supply line; a replacement fluid supply line on the blood return side, which is connected to the blood circuit or the blood purifier, and when the blood returns, the replacement fluid is supplied to the blood circuit through the blood return side replacement fluid supply line, and the position of the blood circuit is located on the blood return side relative to the part connected to the replacement fluid supply line on the blood extraction side; and a control unit, which is configured to switch the replacement fluid supply line from one of the replacement fluid supply line on the blood extraction side and the replacement fluid supply line on the blood return side to the other.

[0012] Effects of the Invention

[0013] According to the present invention, since the replacement fluid supply line is switched from one of the replacement fluid supply line on the blood removal side and the replacement fluid supply line on the blood return side to the other, even if the blood circuit is blocked or narrowed when the blood returns, the blood remaining in the blood circuit can be smoothly returned to the patient's body without reconnecting the line for supplying the replacement fluid when the blood returns. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0015] Figure 2 It is a schematic diagram of a blood circuit included in a blood purification device.

[0016] Figure 3 is a block diagram showing how the main components of a blood purification device are connected.

[0017] Figure 4 1 is a flow chart showing the blood return control process of the blood purification device.

[0018] Figure 5 is a flow chart showing another process of blood return.

[0019] Figure 6 is a schematic diagram of a blood purification device according to a second embodiment of the present invention.

[0020] Figure 7 is a block diagram showing how the main components of a blood purification device are connected.

[0021] Figure 8 This is a flowchart showing the blood return control process of the blood purification device.

[0022] Fig. 9 is a flow chart showing another process of blood return.

[0023] Fig.10 is a schematic diagram of a blood purification device according to a third embodiment of the present invention.

[0024] Fig.11 This is a graph showing changes in pressure and flow rate when the blood purification device performs blood purification treatment.

[0025] Fig.12 This is a conceptual diagram showing a method of identifying an occlusion position of a blood purification device.

[0026] Fig.13 is a block diagram showing how the main components of a blood purification device are connected.

[0027] Fig.14 is a block diagram showing the connection of the main components of another blood purification device.

[0028] Fig.15 is a schematic diagram of a blood purification device according to a fourth embodiment of the present invention.

[0029] Fig.16 : is a graph showing pressure changes and flow rates when the blood purification device performs a blood purification process.

[0030] Fig.17 This is a conceptual diagram showing a method of identifying an occlusion position of a blood purification device.

[0031] Fig.18 is a block diagram showing how the main components of a blood purification device are connected.

[0032] Fig.19 is a block diagram showing the connection of the main components of another blood purification device. DETAILED DESCRIPTION

[0033] Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0034] The blood purification device according to the first embodiment is applied to a hemodialysis device (particularly a hemodialysis device for continuous renal replacement therapy) to purify the patient's blood while circulating it in the extracorporeal circulation. Figure 1 and Figure 2As shown, the device includes: a blood circuit 1, which includes a blood circuit 1a on the blood extraction side and a blood circuit 1b on the blood return side; a dialyzer 2 (blood purifier), which is connected between the blood circuit 1a on the blood extraction side and the blood circuit 1b on the blood return side and is configured to purify the blood flowing through the blood circuit 1; a first dialysate introduction pipeline L1a and a second dialysate introduction pipeline L1b; a first substitution pipeline L2a and a second substitution pipeline L2b; a physiological saline supply pipeline La, which serves as a blood extraction side substitution fluid supply pipeline; a front substitution pipeline L2c and the rear replacement pipeline L2d, which serves as the replacement fluid supply pipeline on the blood return side; the first drainage discharge pipeline L3a and the second drainage discharge pipeline L3b; the blood pump P1; the dialysate introduction pump P2; the first replacement pump P3; the drainage discharge pump P4; the dialysate transfer pump P5; the replacement fluid transfer pump P6; the drainage transfer pump P7; the second replacement pump P8; the replenishment fluid temporary chamber K1, the dialysate temporary chamber K2, and the drainage temporary chamber K3; the weighing device 4; the occlusion identification unit 7; the judgment unit 8; the notification unit 9; the operation unit 10; and the control unit 11.

[0035] According to this embodiment, the blood pump P1, dialysate inlet pump P2, first replacement pump P3, drainage discharge pump P4, dialysate transfer pump P5, replacement fluid transfer pump P6, drainage transfer pump P7 and second replacement pump P8 are all peristaltic pumps, which transport liquid by squeezing a flexible tube to form a flow path.

[0036] The blood circuit 1a on the blood extraction side and the blood circuit 1b on the blood return side are provided with respective connectors at their distal ends, through which the blood extraction side puncture needle and the blood return side puncture needle (not shown) can be connected thereto. The blood circuit 1a on the blood extraction side and the blood circuit 1b on the blood return side are also provided with respective clamping parts V1 and V2 at their distal end portions, and the clamping parts V1 and V2 are both solenoid valves, etc., and thereby the respective flow paths can be opened and closed as required. While the patient is punctured with the blood extraction side puncture needle connected to the distal end of the blood circuit 1a on the blood extraction side and the blood return side puncture needle connected to the distal end of the blood circuit 1b on the blood return side, the patient's blood can be circulated extracorporeally through the blood circuit 1 by opening the clamping parts V1 and V2 and starting the blood pump P1.

[0037] Specifically, when the blood pump P1 is started and the patient is punctured with the blood extraction side puncture needle and the blood return side puncture needle, the patient's blood flows through the blood extraction side blood circuit 1a and reaches the dialyzer 2, where the blood is purified. Then, the blood flows back into the patient's body through the blood return side blood circuit 1b. In this specification, the side provided with the puncture needle for extracting blood (blood sampling) is called the "blood extraction side", and the side provided with the puncture needle for returning blood to the patient is called the "blood return side". The "blood extraction side" and the "blood return side" are not defined according to whether the puncture object is an artery or a vein.

[0038] The blood return side blood circuit 1b is provided with an air trap chamber 3 at its middle position. The blood circulated extracorporeally through the blood circuit 1 is subjected to air bubble removal at the air trap chamber 3 and then returned to the patient. As an alternative to the embodiment of puncturing the patient's blood vessels with the blood extraction side puncture needle and the blood return side puncture needle, the following schemes may be adopted: an embodiment of inserting a double lumen catheter into the patient's subclavian vein or femoral vein, an embodiment of inserting a double lumen catheter into the patient's arm blood vessels, etc.

[0039] The dialyzer 2 has: a blood inlet 2a for introducing blood; a blood outlet 2b for outlet blood; a dialysate inlet 2c for introducing dialysate; a dialysate outlet 2d for outlet dialysate; a blood flow path (not shown) extending between the blood inlet 2a and the blood outlet 2b and for allowing blood to flow therein; a dialysate flow path (not shown) extending between the dialysate inlet 2c and the dialysate outlet 2d and for allowing dialysate to flow therein; and a blood purification membrane (not shown) separating the blood flow path from the dialysate flow path and for purifying blood flowing in the blood flow path.

[0040] Specifically, the dialyzer 2 includes a housing, from which a blood inlet 2a, a blood outlet 2b, a dialysate inlet 2c, and a dialysate outlet 2d protrude. A blood extraction side blood circuit 1a is connected to the blood inlet 2a. A blood return side blood circuit 1b is connected to the blood outlet 2b. A second dialysate inlet line L1b is connected to the dialysate inlet 2c. A first drain line L3a is connected to the dialysate outlet 2d.

[0041] The dialyzer 2 accommodates a plurality of hollow fiber membranes formed by hollow fibers, which serve as blood purification membranes for purifying blood. Specifically, the space inside each blood purification membrane formed by the hollow fibers serves as a blood flow path, and the space between the housing and the hollow fibers serves as a dialysate flow path. Each blood purification membrane formed by the hollow fiber membrane has a plurality of micropores (pores) extending from the outer surface to the inner surface. Impurities contained in the blood flowing in the blood flow path can be infiltrated (filtered) into the dialysate flowing in the dialysate flow path by the hollow fiber membrane.

[0042] The dialysate inlet 2c is connected to the dialysate bag B1 through the first dialysate inlet line L1a, the dialysate temporary chamber K2, and the second dialysate inlet line L1b. With the start of the dialysate inlet pump P2 and the dialysate transfer pump P5, the dialysate stored in the dialysate bag B1 can be introduced into the dialyzer 2. The dialysate to be introduced into the dialyzer 2 is heated by the heating device H1.

[0043] The dialysate outlet 2d is connected to the first drain line L3a. By starting the drain pump P4 and the drain transfer pump P7, the drain discharged from the dialyzer 2 can be discharged to the outside of the device through the drain temporary chamber K3 and the second drain line L3b. The first drain line L3a is provided with a pressure sensor Pa, which can detect the fluid pressure of the drain discharged from the dialyzer 2.

[0044] A predetermined amount of supplementary fluid (replacement fluid) is stored in the supplementary fluid bag B2. By starting the first replacement pump P3 and the replacement fluid transfer pump P6, the supplementary fluid (replacement fluid) can be supplied to the blood circuit 1 through the first replacement pipeline L2a, the supplementary fluid temporary chamber K1, and the second replacement pipeline L2b, thereby performing replacement (pre-replacement or post-replacement). The supplementary fluid (replacement fluid) to be introduced into the blood circuit 1 is heated by the heating device H2, and air bubbles are removed at the air trap chamber 6. A pressure sensor Pb is provided at the upper part of the air trap chamber 6.

[0045] More specifically, the distal end of the second substitution line L2b is connected to the front substitution line L2c and the rear substitution line L2d. The front substitution line L2c is connected to a point of the blood circuit 1a on the blood extraction side between the blood pump P1 and the dialyzer 2. The rear substitution line L2d is connected to the air trap chamber 3 provided in the blood circuit 1b on the blood return side. The front substitution line L2c and the rear substitution line L2d are respectively provided with a check valve near the connection with the blood circuit 1a on the blood extraction side and the air trap chamber 3.

[0046] The front replacement line L2c is provided with a second replacement pump P8. When the second replacement pump P8 is started at a flow rate substantially the same as that of the first replacement pump P3, the supplementary liquid in the temporary replacement chamber K1 can be introduced into the blood circuit 1a on the blood extraction side for front replacement. On the other hand, when the first replacement pump P3 is in operation and the second replacement pump P8 is stopped, the supplementary liquid in the temporary replacement chamber K1 can be introduced into the blood circuit 1b on the blood return side for rear replacement.

[0047] Furthermore, when the second replacement pump P8 is started at a flow rate less than that of the first replacement pump P3, the supplemental fluid can be introduced into the blood circuit 1a on the blood removal side and the blood circuit 1b on the blood return side for pre-replacement and post-replacement at a ratio corresponding to the flow rate of the second replacement pump P8. By controlling the first replacement pump P3 and the second replacement pump P8 to change the ratio between the fluid delivery amounts of the first replacement pump P3 and the second replacement pump P8 as needed, the ratio between the pre-replacement amount and the post-replacement amount can be changed.

[0048] On the other hand, Figure 2As shown, the blood circuit 1a on the blood extraction side of the blood circuit 1 according to the present embodiment is provided with a physiological saline supply line La (blood extraction side replacement fluid supply line), and when the blood returns, the replacement fluid (physiological saline in this embodiment) can be supplied to the blood circuit 1 through the physiological saline supply line La. The physiological saline supply line La is connected to an upstream position closer to the patient than the installation position E3 of the blood pump P1 (the upstream position is a connection position E2 located between the distal end E1 of the blood circuit 1a on the blood extraction side and the installation position E3 of the blood pump P1). The physiological saline supply line La is provided with a physiological saline bag B3 in which a predetermined amount of physiological saline is stored. The flow path of the physiological saline supply line La can be opened and closed by a clamping portion V3.

[0049] like Figure 2 As shown, according to the present embodiment, the front substitution line L2c and the rear substitution line L2d are respectively connected to downstream positions different from the upstream positions in the blood circuit 1 (the downstream positions are respectively located between the installation position E3 of the blood pump P1 and the distal end E6 of the blood circuit 1b on the blood return side). When the blood returns, the substitution fluid can be supplied to the blood extraction side blood circuit 1a or the blood return side blood circuit 1b. Specifically, the front substitution line L2c is connected to the connection position E4 located between the installation position E3 of the blood pump P1 and the dialyzer 2; and the rear substitution line L2d is connected to the connection position E5 located between the dialyzer 2 and the distal end E6 of the blood circuit 1b on the blood return side (in the present embodiment, the connection position E5 is the position at the air trap chamber 3).

[0050] During the blood purification process, the clamping parts V1 and V2 are opened, and the clamping part V3 is closed, so that the patient's blood circulates extracorporeally in the blood circuit 1, and the blood purification process is performed in the dialyzer 2. In addition, when the first substitution pump P3 and the substitution fluid transfer pump P6 are in operation, if the second substitution pump P8 is selectively started, the supplementary fluid can be supplied to the blood circuit 1a on the blood extraction side through the front substitution line L2c for performing the front substitution, or the supplementary fluid can be supplied to the blood circuit 1b on the blood return side through the rear substitution line L2d for post substitution.

[0051] The blood circuit 1 is also provided with respective pressure sensors (first pressure sensor S1, second pressure sensor S2 and third pressure sensor S3) at predetermined positions thereof, each of which serves as a pressure detection unit. Therefore, the pressure (fluid pressure) in the respective blood flow paths of the blood circuit 1 and the dialyzer 2 can be detected. The first pressure sensor S1 is configured to detect the pressure at an upstream position (a position between the distal end E1 of the blood circuit 1a on the blood extraction side and the installation position E3 of the blood pump P1). The second pressure sensor S2 and the third pressure sensor S3 are configured to respectively detect the pressure on the upstream side and the downstream side of the dialyzer 2 at respective downstream positions (a position between the installation position E3 of the blood pump P1 and the distal end E6 of the blood circuit 1b on the blood return side).

[0052] Specifically, the first pressure sensor S1 is set at a position between the connection position E2 of the physiological saline supply line La and the installation position E3 of the blood pump P1, and the second pressure sensor S2 is set at a position between the installation position E3 of the blood pump P1 and the dialyzer 2, and the third pressure sensor S3 is set at a position between the dialyzer 2 and the distal end E6 of the blood return side blood circuit 1b (air trap chamber 3). Therefore, the pressure sensors S1 to S3 can detect the pressure (fluid pressure) at various positions of the blood flow path. Note that the venous pressure sensor configured to detect the pressure of the air layer in the air trap chamber 3 is used as the third pressure sensor S3 to detect the fluid pressure.

[0053] See also Figure 3 The occlusion recognition unit 7 is a computing unit (e.g., a microcomputer) that is electrically connected to the first pressure sensor S1, the second pressure sensor S2, and the third pressure sensor S3, and is configured to recognize an occlusion position of a blood flow path in the blood circuit 1 or the dialyzer 2 based on the pressures detected by the first pressure sensor S1, the second pressure sensor S2, and the third pressure sensor S3. The recognition of any occlusion position by the occlusion recognition unit 7 can be performed during blood purification treatment or during blood return.

[0054] For example, if the detection value of the first pressure sensor S1 increases, while the detection value of the second pressure sensor S2 decreases, it can be determined that occlusion or narrowing has occurred between the first pressure sensor S1 and the second pressure sensor S2. On the other hand, if the detection value of the second pressure sensor S2 increases, while the detection value of the third pressure sensor S3 is normal, it can be determined that occlusion or narrowing has occurred between the second pressure sensor S2 and the air trap chamber 3. If the detection values ​​of the first to third pressure sensors S1 to S3 are all normal, it can be determined that no occlusion or narrowing has occurred in the blood circuit 1.

[0055] See also Figure 3The determination unit 8 is a computing unit (e.g., a microcomputer) and is electrically connected to the occlusion recognition unit 7. If the occlusion recognition unit 7 recognizes the occlusion position, the determination unit 8 determines, based on the occlusion position, to switch the line for supplying the replacement fluid (supplementary fluid) at the time of blood return from one of the blood withdrawal side replacement fluid supply line (physiological saline supply line La) and the blood return side replacement fluid supply line (front replacement line L2c and rear replacement line L2d) to the other.

[0056] For example, when the occlusion recognition unit 7 recognizes that occlusion or narrowing occurs between the connection position E2 of the physiological saline supply line La and the installation position E3 of the blood pump P1, the determination unit 8 determines to switch from the physiological saline supply line La to the front substitution line L2c to supply the substitution fluid. On the other hand, when the occlusion recognition unit 7 recognizes that occlusion or narrowing occurs between the connection position E4 of the front substitution line L2c and the dialyzer 2, the determination unit 8 determines to switch from the physiological saline supply line La or the front substitution line L2c to the rear substitution line L2d to supply the substitution fluid.

[0057] The notification unit 9 is an output device electrically connected to the determination unit 8. When the determination unit 8 determines that the replacement fluid supply line needs to be switched, the notification unit 9 provides information on switching the replacement fluid supply line when the blood returns. The notification unit 9 is, for example, any one of the following: a display device (e.g., a display) for displaying an image prompting the switching; an output device (e.g., a speaker) for outputting a sound prompting the switching; a lighting device (e.g., an LED) for emitting light or flashing to prompt the switching; and the like.

[0058] For example, at the time of blood return, if the determination unit 8 determines that the replacement fluid is supplied by switching from the physiological saline supply line La to the front replacement line L2c, the notification unit 9 provides information to prompt the operation of supplying the replacement fluid (supplementary fluid) through the front replacement line L2c instead of supplying the replacement fluid (physiological saline) through the physiological saline supply line La. On the other hand, if the determination unit 8 determines that the replacement fluid is supplied by switching from the physiological saline supply line La or the front replacement line L2c to the rear replacement line L2d, the notification unit 9 provides information to prompt the operation of supplying the replacement fluid through the rear replacement line L2d instead of supplying the replacement fluid through the physiological saline supply line La or the front replacement line L2c.

[0059] When the blood is returned, if the information for switching the replacement fluid supply line is provided by the notification unit 9, the switching operation is performed on the operation unit 10. For example, the operation of opening or closing the clamping portion V1 and the operation of starting or stopping the relevant pumps can be performed on the operation unit 10. More specifically, the operation of the blood pump P1 can be stopped in a state where the clamping portion V1 is closed, and the second replacement pump P8 can be started in a state where the first replacement pump P3 and the replacement fluid transfer pump P6 are in operation, thereby switching the supply of the replacement fluid (physiological saline) through the physiological saline supply line La to the supply of the replacement fluid (supplementary fluid) through the front replacement line L2c.

[0060] On the other hand, by keeping the clamping part V1 closed, the blood pump P1 stopped, and the second replacement pump P8 stopped while the first replacement pump P3 and the replacement fluid transfer pump P6 are running, the replacement fluid (replenishment fluid) supplied through the front replacement pipeline L2c can be switched to the replacement fluid (replenishment fluid) supplied through the rear replacement pipeline L2d. In addition, by stopping the operation of the blood pump P1 while the clamping part V1 is closed, and stopping the second replacement pump P8 while the first replacement pump P3 and the replacement fluid transfer pump P6 are running, the replacement fluid (physiological saline) supplied through the physiological saline supply pipeline La can be switched to the replacement fluid (replenishment fluid) supplied through the rear replacement pipeline L2d.

[0061] The control unit 11 is configured to switch the replacement fluid supply line from one of the blood removal side replacement fluid supply line and the blood return side replacement fluid supply line to the other. Figure 3 According to the present embodiment, the control unit 11 is a microcomputer or the like, which is electrically connected to each of the operation unit 10, the blood pump P1, the first substitution pump P3, the substitution fluid transfer pump P6, and the second substitution pump P8. If the operator performs a predetermined operation in response to the information provided by the notification unit 9, the control unit 11 switches the substitution fluid supply line from one of the blood extraction side substitution fluid supply line (physiological saline supply line) and the blood return side substitution fluid supply line (front substitution line L2c or rear substitution line L2d) to the other. The operation unit 10 may be electrically connected to all or part of the related elements such as the occlusion identification unit 7, the determination unit 8, and the notification unit 9. Any electrical connection structure may be adopted.

[0062] Now, refer to Figure 4 The flowchart shown explains the blood return control process of the blood purification device according to the first embodiment.

[0063] After the blood purification treatment is completed, blood return begins. Thus, the dialysate supply to the dialyzer 2 is stopped, and the blood pump P1 is stopped with the clamping part V3 open. Thus, the saline in the saline bag B3 is supplied to the blood circuit 1. The blood in the flow path between the distal end E1 and the connection position E2 of the blood circuit 1a on the blood extraction side is replaced with a replacement fluid by the dead weight of the saline generated by the head difference, and the replaced blood is thus returned to the patient's body.

[0064] Subsequently, the clamping portion V1 is closed, and the following process is performed to return the blood in the blood circuit 1 from the connection position E2 to the distal end E6 of the blood circuit 1b on the blood return side. Specifically, in S1, it is checked whether the occlusion identification portion 7 has identified any occluded position. If it is determined that no occluded position is identified (no occlusion or stenosis is detected), the blood pump P1 is started in S7. Then, in S8, it is checked whether the specified blood return amount is reached. In this step, the first substitution pump P3, the substitution fluid transfer pump P6, and the second substitution pump P8 remain stopped. In addition, the blood pump P1 remains in operation until the specified blood return amount is reached. If it is determined that the specified amount is reached, the blood return is terminated.

[0065] On the other hand, if it is determined in S1 that the occlusion position is identified, the determination unit 8 determines in S2 to switch the replacement fluid supply line. For example, if it is determined that occlusion or narrowing occurs between the distal end E1 of the blood circuit 1a on the blood extraction side and the installation position E3 of the blood pump P1, the determination unit 8 determines to switch from the physiological saline supply line La to the front replacement line L2c to supply the replacement fluid. On the other hand, if the occlusion identification unit 7 determines that occlusion or narrowing occurs between the installation position E3 of the blood pump P1 and the dialyzer 2, the determination unit 8 determines to switch from the physiological saline supply line La or the front replacement line L2c to the rear replacement line L2d to supply the replacement fluid.

[0066] In S3, after the notification unit 9 provides information for switching the replacement fluid supply line, it is checked in S4 whether the switching operation is performed according to the information provided by the notification unit 9. If it is determined in S4 that the operator performs the switching operation according to the information provided by the notification unit 9, the process proceeds to S5, in which the control unit 11 starts the first replacement pump P3 and the replacement fluid transfer pump P6 while the blood pump P1 remains stopped according to the switching operation performed on the operation unit 10. In the switching operation, the operation of closing the clamping unit V3 is also performed.

[0067] At this time, if the replacement fluid is to be supplied through the front replacement line L2c, the control unit 11 starts the first replacement pump P3 and the replacement fluid transfer pump P6 while the blood pump P1 is stopped, and starts the second replacement pump P8 (thereby, the control unit 11 changes the operation states of the blood pump P1, the first replacement pump P3, the replacement fluid transfer pump P6, and the second replacement pump P8, thereby switching the replacement fluid supply line from the physiological saline supply line La to the front replacement line L2c). On the other hand, if the replacement fluid is to be supplied through the rear replacement line L2d, the control unit 11 starts the first replacement pump P3 and the replacement fluid transfer pump P6 while the blood pump P1 is stopped, but keeps the second replacement pump P8 stopped (similar to the above case, the control unit 11 changes the operation states of the blood pump P1, the first replacement pump P3, the replacement fluid transfer pump P6, and the second replacement pump P8, thereby switching the replacement fluid supply line from the physiological saline supply line or the front replacement line L2c to the rear replacement line L2d).

[0068] After starting the replacement pump in S5 (after starting the first replacement pump P3 and the replacement fluid transfer pump P6 and selectively starting the second replacement pump P8), check in S6 whether the specified blood return volume has been reached. The replacement pumps remain in operation (the first replacement pump P3 and the replacement fluid transfer pump P6 remain in operation and the second replacement pump P8 selectively remains in operation) until the specified blood return volume is reached. If it is determined that the specified volume has been reached, the blood return is terminated. During this blood return process, the identification of any occluded position by the occlusion identification unit 7 can be performed in the final stage of blood purification treatment.

[0069] Next, refer to Figure 5 The flowchart shown explains another process of the blood return control in the blood purification apparatus according to the first embodiment.

[0070] After the blood purification treatment is completed, blood return begins. As a result, the dialysate supply to the dialyzer 2 is stopped, and the blood pump P1 is stopped with the clamp V3 open. As a result, the saline in the saline bag B3 is supplied to the blood circuit 1. The blood in the flow path between the distal end E1 and the connection position E2 of the blood circuit 1a on the blood extraction side is replaced with a replacement fluid by the dead weight of the saline generated by the water head difference, and the replaced blood is returned to the patient's body.

[0071] Subsequently, the clamping portion V1 is closed, and the following process is performed to return the blood in the blood circuit 1 from the connection position E2 to the distal end E6 of the blood circuit 1b on the blood return side. Specifically, in S1, the blood pump P1 is started. Then, in S2, it is checked whether the occlusion identification portion 7 identifies any occluded position. If it is determined that no occluded position is identified (no occlusion or stenosis is detected), it is checked in S8 whether the specified blood return amount is reached. In this step, the first substitution pump P3, the substitution fluid transfer pump P6, and the second substitution pump P8 remain stopped. In addition, the blood pump P1 remains in operation until the specified blood return amount is reached. If it is determined that the specified amount has been reached, the blood return is terminated.

[0072] On the other hand, if it is determined in S2 that the occlusion position is recognized, the determination unit 8 determines in S3 to switch the replacement fluid supply line. For example, if it is determined that the connection position E2 of the physiological saline supply line La and the installation position E3 of the blood pump P1 are occluded or narrowed, the determination unit 8 determines to switch from the physiological saline supply line La to the front replacement line L2c to supply the replacement fluid. On the other hand, if the occlusion identification unit 7 determines that the connection position E4 of the front replacement line L2c and the dialyzer 2 is occluded or narrowed, the determination unit 8 determines to switch from the physiological saline supply line La or the front replacement line L2c to the rear replacement line L2d to supply the replacement fluid.

[0073] In S4, after the notification unit 9 provides information for switching the replacement fluid supply line, it is checked in S5 whether the switching operation is performed according to the information provided by the notification unit 9. If it is determined in S5 that the operator performs the switching operation according to the information provided by the notification unit 9, the process proceeds to S6, where the control unit 11 stops the blood pump P1 but starts the first replacement pump P3 and the replacement fluid transfer pump P6 according to the switching operation performed on the operation unit 10. Here, the operation of closing the clamping unit V3 is also performed.

[0074] In this step, if the replacement fluid is to be supplied through the front replacement line L2c switched from the physiological saline supply line La, the control unit 11 starts the first replacement pump P3 and the replacement fluid transfer pump P6 while the blood pump P1 is stopped, and starts the second replacement pump P8. On the other hand, if the replacement fluid is to be supplied through the rear replacement line L2d switched from the physiological saline supply line La (front replacement line L2c), the control unit 11 starts the first replacement pump P3 and the replacement fluid transfer pump P6 while the blood pump P1 is stopped, but keeps the second replacement pump P8 stopped.

[0075] After starting the replacement pump in S6 (after starting the first replacement pump P3 and the replacement fluid transfer pump P6 and selectively starting the second replacement pump P8), it is checked in S7 whether the specified blood return volume has been reached. The replacement pumps are kept running (the first replacement pump P3 and the replacement fluid transfer pump P6 are kept running and the second replacement pump P8 is selectively kept running) until the specified blood return volume is reached. If it is determined that the specified volume has been reached, the blood return is terminated. In this blood return process, the occlusion recognition unit 7 can perform recognition of any occluded position immediately after the start of blood return.

[0076] Next, a blood purification device according to a second embodiment of the present invention will be described.

[0077] The blood purification device according to the second embodiment is suitable for a hemodialysis device (particularly a hemodialysis device for continuous renal replacement therapy) that purifies the patient's blood while circulating it extracorporeally. Figure 6 As shown, the device includes a blood circuit 1; a dialyzer 2 (blood purifier); a first dialysate inlet line L1a and a second dialysate inlet line L1b; a first substitution line L2a and a second substitution line L2b; a physiological saline supply line La as a substitution liquid supply line on the blood extraction side; a front substitution line L2c and a rear substitution line L2d as substitution liquid supply lines on the blood return side; a first drainage discharge line L3a and a second drainage discharge line L3b; a blood pump P1; a dialysate inlet pump P2; a first substitution pump P3; a drainage discharge pump P4; a dialysate transfer pump P5, a substitution liquid transfer pump P6, a drainage transfer pump P7, a second substitution pump P8, a supplement liquid temporary chamber K1, a dialysate temporary chamber K2, a drainage temporary chamber K3, a weighing device 4, an occlusion identification unit 7, a determination unit 8, and a control unit 11. The same elements as those described in the first embodiment are represented by corresponding reference numerals, and detailed descriptions of these elements are omitted.

[0078] See also Figure 7, the control unit 11 is a microcomputer, etc., which is electrically connected to the determination unit 8, the blood pump P1, and the substitution pumps (the first substitution pump P3, the substitution fluid transfer pump P6, and the second substitution pump P8). In the present embodiment, if the determination unit 8 determines to switch the substitution fluid supply line from one of the substitution fluid supply line on the blood extraction side and the substitution fluid supply line on the blood return side to the other, the control unit 11 automatically switches the substitution fluid supply line from one of the substitution fluid supply line on the blood extraction side and the substitution fluid supply line on the blood return side to the other. For example, when the blood returns, if the determination unit 8 determines to switch from the physiological saline supply line La to the front substitution line L2c to supply the substitution fluid, the supply of the substitution fluid (physiological saline) through the physiological saline supply line La is automatically switched to the supply of the substitution fluid (supplementary fluid) through the front substitution line L2c. On the other hand, if the determination unit 8 determines that the replacement fluid is supplied by switching from the saline supply line La or the front replacement line L2c to the rear replacement line L2d, the replacement fluid supply through the saline supply line La or the front replacement line L2c is automatically switched to the replacement fluid supply through the rear replacement line L2d.

[0079] Next, refer to Figure 8 The flowchart shown explains the blood return control process of the blood purification device according to the second embodiment.

[0080] After the blood purification treatment is completed, blood return begins. Thus, the dialysate supply to the dialyzer 2 is stopped, and the blood pump P1 is stopped with the clamping part V3 open. Thus, the saline in the saline bag B3 is supplied to the blood circuit 1. The blood in the flow path between the distal end E1 and the connection position E2 of the blood circuit 1a on the blood extraction side is replaced with a replacement fluid by the dead weight of the saline generated by the water head difference, and the replaced blood is returned to the patient's body.

[0081] Subsequently, the clamping portion V1 is closed, and the following process is performed to return the blood in the blood circuit 1 from the connection position E2 to the distal end E6 of the blood circuit 1b on the blood return side. Specifically, in S1, it is checked whether the occlusion identification portion 7 identifies any occluded position. If it is determined that no occluded position is identified (occlusion or stenosis is not detected), the blood pump P1 is started in S6. Then, in S7, it is checked whether the specified blood return amount is reached. In this step, the first replacement pump P3, the replacement fluid transfer pump P6 and the second replacement pump P8 remain stopped. In addition, the blood pump P1 remains in operation until the specified blood return amount is reached. If it is determined that the specified amount is reached, the blood return is terminated.

[0082] On the other hand, if it is determined in S1 that the occlusion position is identified, the determination unit 8 determines in S2 to switch the replacement fluid supply line. For example, if the occlusion identification unit 7 determines that occlusion or narrowing occurs between the connection position E2 of the physiological saline supply line La and the installation position E3 of the blood pump P1, the determination unit 8 determines to switch from the physiological saline supply line La to the front replacement line L2c to supply the replacement fluid. On the other hand, if the occlusion identification unit 7 determines that occlusion or narrowing occurs between the connection position E4 of the front replacement line L2c and the dialyzer 2, the determination unit 8 determines to switch from the physiological saline supply line La or the front replacement line L2c to the rear replacement line L2d to supply the replacement fluid.

[0083] Subsequently, in S3, the control unit 11 performs switching control according to the determination result of the determination unit 8. In addition, in S4, the control unit 11 starts the first replacement pump P3 and the replacement fluid transfer pump P6, while the blood pump P1 remains stopped. In this step, if the replacement fluid is to be supplied through the front replacement pipeline L2c, the control unit 11 starts the first replacement pump P3 and the replacement fluid transfer pump P6 in the state where the blood pump P1 is stopped, and starts the second replacement pump P8. On the other hand, if the replacement fluid is to be supplied through the rear replacement pipeline L2d, the control unit 11 starts the first replacement pump P3 and the replacement fluid transfer pump P6 in the state where the blood pump P1 is stopped, but keeps the second replacement pump P8 stopped. The switching control mentioned here refers to the control operation of switching the operating state of related elements such as the blood pump P1, the first replacement pump P3, the replacement fluid transfer pump P6, and the second replacement pump P8 (the operating state of the related actuator), but is not limited thereto. Alternatively, the switching control can also be an operation of switching the mode representing the replacement fluid supply pipeline (the internal state of the blood purification device). In addition, the operation of closing the clamping portion V3 can also be performed during the switching control.

[0084] After starting the replacement pump in S4 (after starting the first replacement pump P3 and the replacement fluid transfer pump P6 and selectively starting the second replacement pump P8), check in S5 whether the specified blood return volume has been reached. The replacement pumps remain in operation (the first replacement pump P3 and the replacement fluid transfer pump P6 remain in operation and the second replacement pump P8 selectively remains in operation) until the specified blood return volume is reached. If it is determined that the specified volume has been reached, the blood return is terminated. During this blood return process, the identification of any occluded position by the occlusion identification unit 7 can be performed in the final stage of blood purification treatment.

[0085] Now, refer to Fig. 9 The flowchart shown explains another process of the blood return control in the blood purification apparatus according to the second embodiment.

[0086] After the blood purification treatment is completed, blood return begins. As a result, the dialysate supply to the dialyzer 2 is stopped, and the blood pump P1 is stopped with the clamp V3 open. As a result, the saline in the saline bag B3 is supplied to the blood circuit 1. The blood in the flow path between the distal end E1 and the connection position E2 of the blood circuit 1a on the blood extraction side is replaced with a replacement fluid by the dead weight of the saline generated by the water head difference, and the replaced blood is returned to the patient's body.

[0087] Subsequently, the clamping portion V1 is closed, and the following process is performed to return the blood in the blood circuit 1 from the connection position E2 to the distal end E6 of the blood circuit 1b on the blood return side. Specifically, in S1, the blood pump P1 is started. Then, in S2, it is checked whether the occlusion identification portion 7 identifies any occluded position. If it is determined that no occluded position is identified (occlusion or stenosis is not detected), it is checked in S7 whether the specified blood return amount is reached. In this step, the first substitution pump P3, the substitution fluid transfer pump P6 and the second substitution pump P8 remain stopped. In addition, the blood pump P1 remains in operation until the specified blood return amount is reached. If it is determined that the specified amount has been reached, the blood return is terminated.

[0088] On the other hand, if it is determined in S2 that the occlusion position is identified, the determination unit 8 determines in S3 to switch the replacement fluid supply line. For example, if the occlusion identification unit 7 determines that occlusion or narrowing occurs between the connection position E2 of the physiological saline supply line La and the installation position E3 of the blood pump P1, the determination unit 8 determines to switch from the physiological saline supply line La to the front replacement line L2c to supply the replacement fluid. On the other hand, if the occlusion identification unit 7 determines that occlusion or narrowing occurs between the connection position E4 of the front replacement line L2c and the dialyzer 2, the determination unit 8 determines to switch from the physiological saline supply line La or the front replacement line L2c to the rear replacement line L2d to supply the replacement fluid.

[0089] Subsequently, in S4, the control unit 11 performs switching control according to the determination result of the determination unit 8. Furthermore, in S5, the control unit 11 stops the blood pump P1, but starts the first substitution pump P3 and the substitution fluid transfer pump P6. In this step, if the substitution fluid is to be supplied through the front substitution line L2c switched from the physiological saline supply line La, the control unit 11 starts the first substitution pump P3 and the substitution fluid transfer pump P6 in a state where the blood pump P1 is stopped, and starts the second substitution pump P8. On the other hand, if the substitution fluid is to be supplied through the rear substitution line L2d switched from the physiological saline supply line La, the control unit 11 starts the first substitution pump P3 and the substitution fluid transfer pump P6 in a state where the blood pump P1 is stopped, but keeps the second substitution pump P8 stopped. The switching control mentioned here refers to a control operation of switching the operating states of related elements such as the blood pump P1, the first substitution pump P3, the substitution fluid transfer pump P6, and the second substitution pump P8 (operating states of related actuators), but is not limited thereto. Alternatively, the switching control may be an operation of switching the mode (internal state of the blood purification device) indicating the replacement fluid supply line. In addition, the switching control may also include an operation of closing the clamping part V3.

[0090] After starting the replacement pump in S5 (after starting the first replacement pump P3 and the replacement fluid transfer pump P6 and selectively starting the second replacement pump P8), it is checked in S6 whether the specified blood return volume has been reached. The replacement pumps are kept running (the first replacement pump P3 and the replacement fluid transfer pump P6 are kept running and the second replacement pump P8 is selectively kept running) until the specified blood return volume is reached. If it is determined that the specified volume has been reached, the blood return is terminated. In this blood return process, the occlusion recognition unit 7 can perform recognition of any occluded position immediately after the start of blood return.

[0091] Next, a blood purification device according to a third embodiment of the present invention will be described.

[0092] The blood purification device according to the third embodiment is applied to a hemodialysis device (particularly a hemodialysis device for continuous renal replacement therapy) to purify the patient's blood and circulate the blood in vitro. Fig.10As shown, the device includes: a blood circuit 1; a dialyzer 2 (blood purifier); a first dialysate inlet pipeline L1a and a second dialysate inlet pipeline L1b; a first substitution pipeline L2a and a second substitution pipeline L2b; a physiological saline supply pipeline La as a substitution fluid supply pipeline on the blood removal side; a front substitution pipeline L2c and a rear substitution pipeline L2d as substitution fluid supply pipelines on the blood return side; a first drainage discharge pipeline L3a and a second drainage discharge pipeline L3b; a blood pump P1; a dialysate inlet pump P2; a first substitution pump P3; a drainage discharge pump P4; a dialysate transfer pump P5; a substitution fluid transfer pump P6; a drainage transfer pump P7; a second substitution pump P8; a replenishing fluid temporary chamber K1, a dialysate temporary chamber K2, and a drainage temporary chamber K3; a weighing device 4; a flow rate detection unit E; a blocked position identification unit 12; a switching notification unit 13; an operating unit 14; and an execution unit 15. The same components as those in the first embodiment are denoted by corresponding reference numerals, and detailed description thereof will be omitted.

[0093] The flow velocity detection unit E is configured to detect the flow velocity at a specific position of the flow path in the blood circuit 1, for example, the flow velocity of the priming solution during priming or the blood during blood purification treatment. The flow velocity detection unit E can be based on various detection technologies, for example, a device configured to detect the flow velocity based on the driving speed of a pump such as the blood pump P1, a device configured to directly detect the flow velocity of the fluid in the blood circuit 1, etc.

[0094] The blocking position recognition unit 12 is, for example, a microcomputer, a memory, etc. Fig.13 As shown, the occluded position recognition part 12 is electrically connected to each pressure sensor (S1 to S3) and the flow rate detection part E, and can receive the pressure detected by the pressure sensors (S1 to S3) and the flow rate detected by the flow rate detection part E. The occluded position recognition part 12 according to the present embodiment is connected not only to the pressure sensors (S1 to S3) provided on the blood circuit 1, but also to the pressure sensor Pa provided on the first drainage discharge line L3a, and can receive the pressure at the pressure sensor Pa. Alternatively, the occluded position recognition part 12 may be connected only to the pressure sensors (S1 to S3).

[0095] The occlusion position recognition unit 12 according to the present embodiment utilizes a learning model obtained by machine learning, wherein, in the blood circuit 1, when the flow path is occluded or narrowed, a plurality of data of pressure changes and flow velocity are accumulated, thereby generating accumulated data, which serves as teaching data for identifying any occlusion position of the flow path. Therefore, the occlusion position recognition unit 12 recognizes the occlusion position based on the pressure changes and flow velocity detected by the pressure sensors (S1 to S3) and by the flow velocity detection unit E. Machine learning refers to a technology that uses a computer to learn a large amount of data and automatically constructs an algorithm or model for realizing various tasks (such as classification and prediction). The technology and algorithm for realizing machine learning include, for example, neural networks.

[0096] Now refer to Fig.11 and Fig.12 The specific contents of the machine learning according to the present embodiment are described.

[0097] In the blood circuit, when the flow path is blocked or narrowed, multiple (large) data of pressure changes and flow rates are accumulated in advance in a storage device such as a server, thereby generating accumulated data. For example, if the flow path is narrowed at the installation position of the pressure sensor S2, such as Fig.11 As shown, starting from time T1, the pressure and flow rate increase with time. Then, if the flow path is blocked at time T0, the pressure drops sharply, reducing the flow rate to zero. This change in pressure and flow rate in the flow path is characterized by being greater than when the flow path is neither blocked nor narrowed.

[0098] Such data of pressure changes and flow rates when the flow path of the blood circuit is blocked or narrowed is accumulated in a large amount in a storage device such as a server, and is input to a computer as teaching data for machine learning, and the machine learning is performed to determine the specific position (blocked position) where the blockage or narrowing occurs. The blocked position determination unit 12 stores a learning model (e.g., a program) obtained by the above-mentioned machine learning, and uses the learning model to determine the blocked position at time T0 based on the pressure changes and flow rates detected by the pressure sensors (S1 to S3) and the flow rate detection unit E.

[0099] Furthermore, the occlusion position recognition unit 12 of the present embodiment utilizes a learning model obtained by machine learning, which accumulates not only a plurality of data of pressure changes and flow rates when flow path occlusion or narrowing occurs in the blood circuit 1, but also a plurality of data indicating switching to an appropriate replacement fluid supply line when an occlusion position is recognized, thereby generating accumulated data as teaching data for recognizing any occlusion position and switching to an appropriate replacement fluid supply line when an occlusion position is recognized. Therefore, the occlusion position recognition unit 12 recognizes any occlusion position based on the pressure and flow rate detected by the pressure sensors (S1 to S3) and the flow rate detection unit E, and determines to switch to an appropriate replacement fluid supply line when an occlusion position is recognized.

[0100] The switching notification unit 13 is an output device that is electrically connected to the occlusion position recognition unit 12. When the occlusion position is recognized and the occlusion position recognition unit 12 decides to switch the replacement fluid supply line, the switching notification unit 13 provides information on switching the replacement fluid supply line when the blood returns. The switching notification unit 13 is any of the following, for example: a display device, such as a display, configured to display an image prompting the switching; an output device, such as a speaker, configured to output a sound prompting the switching; a lighting device, such as an LED, configured to emit light or flash to prompt the switching; and the like.

[0101] For example, when the blood is returned, if the occluded position recognition unit 12 determines that the replacement fluid is supplied by switching from the physiological saline supply line La to the front replacement line L2c, the switching notification unit 13 provides information prompting an operation of supplying the replacement fluid (supplementary fluid) through the front replacement line L2c instead of supplying the replacement fluid (physiological saline) through the physiological saline supply line La. On the other hand, if the occluded position recognition unit 12 determines that the replacement fluid is supplied by switching from the physiological saline supply line La or the front replacement line L2c to the rear replacement line L2d, the switching notification unit 13 provides information prompting an operation of supplying the replacement fluid through the rear replacement line L2d instead of supplying the replacement fluid through the physiological saline supply line La or the front replacement line L2c.

[0102] At the time of blood return, if the switching notification unit 13 provides information prompting switching of the replacement fluid supply line, a switching operation is performed on the operation unit 14. For example, an operation of opening or closing the clamping unit V1 and an operation of starting or stopping the relevant pumps can be performed on the operation unit 14. More specifically, by stopping the operation of the blood pump P1 in a state where the clamping unit V1 is closed and starting the second replacement pump P8 in a state where the first replacement pump P3 and the replacement fluid transfer pump P6 are in operation, it is possible to switch the supply of the replacement fluid (physiological saline) through the physiological saline supply line La to the supply of the replacement fluid (supplementary fluid) through the front replacement line L2c.

[0103] On the other hand, by keeping the clamping part V1 closed and the blood pump P1 stopped and the second replacement pump P8 stopped while the first replacement pump P3 and the replacement fluid transfer pump P6 are running, the replacement fluid (replenishment fluid) supplied through the front replacement pipeline L2c can be switched to the replacement fluid (replenishment fluid) supplied through the rear replacement pipeline L2d. In addition, by stopping the operation of the blood pump P1 while the clamping part V1 is closed and stopping the second replacement pump P8 while the first replacement pump P3 and the replacement fluid transfer pump P6 are running, the replacement fluid (physiological saline) supplied through the physiological saline supply pipeline La can be switched to the replacement fluid (replenishment fluid) supplied through the rear replacement pipeline L2d.

[0104] The execution unit 15 is configured to switch the replacement fluid supply line from one of the blood removal side replacement fluid supply line and the blood return side replacement fluid supply line to the other. Fig.13The execution unit 15 according to the present embodiment is a microcomputer or the like, which is electrically connected to each of the operation unit 14, the blood pump P1, the first substitution pump P3, the substitution fluid transfer pump P6, and the second substitution pump P8. If the operator performs a predetermined operation in response to the information provided by the switching notification unit 13, the execution unit 15 switches the substitution fluid supply line from one of the blood removal side substitution fluid supply line (physiological saline supply line) and the blood return side substitution fluid supply line (front substitution line L2c or rear substitution line L2d) to the other.

[0105] Or, refer to Fig.14 The execution unit 15 may be a microcomputer or the like, which is electrically connected to the occlusion position recognition unit 12, the blood pump P1, and the substitution pumps (the first substitution pump P3, the substitution fluid transfer pump P6, and the second substitution pump P8), and is configured to not only switch the substitution fluid supply line from one of the blood extraction side substitution fluid supply line and the blood return side substitution fluid supply line to the other, but also automatically switch to the substitution fluid supply line determined to be appropriate if the occlusion position recognition unit 12 recognizes the occlusion position and determines that the substitution fluid supply line is to be switched to an appropriate substitution fluid supply line. At this time, for example, when the blood is returned, if the occlusion position recognition unit 12 determines that the substitution fluid is to be supplied by switching from the physiological saline supply line La to the front substitution line L2c, the substitution fluid (physiological saline) supplied through the physiological saline supply line La is automatically switched to the substitution fluid (supplementary fluid) supplied through the front substitution line L2c. On the other hand, if the occlusion position recognition unit 12 determines that the replacement fluid is supplied by switching from the saline supply line La or the front replacement line L2c to the rear replacement line L2d, the replacement fluid supply from the saline supply line La or the front replacement line L2c is automatically switched to the rear replacement line L2d.

[0106] Next, a blood purification device according to a fourth embodiment of the present invention will be described.

[0107] The blood purification device according to the fourth embodiment is suitable for a hemodialysis device (particularly a hemodialysis device for continuous renal replacement therapy) that purifies the patient's blood while circulating it outside the body. Fig.15As shown, the device includes: a blood circuit 1; a dialyzer 2 (blood purifier); a first dialysate inlet pipeline L1a and a second dialysate inlet pipeline L1b; a first substitution pipeline L2a and a second substitution pipeline L2b; a physiological saline supply pipeline La as a substitution fluid supply pipeline on the blood removal side; a front substitution pipeline L2c and a rear substitution pipeline L2d as substitution fluid supply pipelines on the blood return side; a first drainage discharge pipeline L3a and a second drainage discharge pipeline L3b; a blood pump P1; a dialysate inlet pump P2; a first substitution pump P3; a drainage discharge pump P4; a dialysate transfer pump P5; a substitution fluid transfer pump P6; a drainage transfer pump P7; a second substitution pump P8; a replenishing fluid temporary chamber K1, a dialysate temporary chamber K2, and a drainage temporary chamber K3; a weighing device 4; a flow rate detection unit E; an occlusion determination unit 16; a blood return notification unit 17; an operating unit 14; and an execution unit 15. The same components as those described in the first or third embodiment are denoted by corresponding reference numerals, and detailed description thereof will be omitted.

[0108] The occlusion estimation unit 16 is, for example, a microcomputer, a memory, etc. Fig.18 As shown, the occlusion inference unit 16 is electrically connected to each pressure sensor (S1 to S3) and the flow rate detection unit E, and is capable of receiving the pressure detected by the pressure sensors (S1 to S3) and the flow rate detected by the flow rate detection unit E. The occlusion inference unit 16 according to the present embodiment is connected not only to the pressure sensors (S1 to S3) provided on the blood circuit 1, but also to the pressure sensor Pa provided on the first drain discharge line L3a, and is capable of receiving the pressure at the pressure sensor Pa. Alternatively, the occlusion inference unit 16 may be exclusively connected to the pressure sensors (S1 to S3).

[0109] The occlusion inference unit 16 according to the present embodiment utilizes a learning model obtained by machine learning, wherein a plurality of data of pressure changes and flow rates are accumulated when occlusion or narrowing of the flow path occurs in the blood circuit 1, thereby generating accumulated data, which serves as teaching data for identifying any occlusion position of the flow path. Therefore, the occlusion inference unit 16 infers any occlusion position that will occur within a predetermined period of time based on the pressure changes and flow rates detected by the pressure sensors (S1 to S3) and by the flow rate detection unit E. For machine learning, refer to the description of the third embodiment.

[0110] Now refer to Fig.16 and Fig.17 The specific contents of the machine learning according to the present embodiment are described.

[0111] In the blood circuit, when the flow path is blocked or narrowed, multiple (large) data of pressure changes and flow rates are accumulated in advance in a storage device such as a server, thereby generating accumulated data. For example, if the flow path is narrowed at the installation position of the pressure sensor S2, such as Fig.16As shown, starting from time T1, the pressure and flow rate increase with time. Then, if the flow path is blocked at time T0, the pressure drops sharply, reducing the flow rate to zero. This change in pressure and flow rate in the flow path is characterized by being greater than when the flow path is neither blocked nor narrowed.

[0112] Such data of pressure changes and flow rates when the flow path of the blood circuit is blocked or narrowed is accumulated in large quantities in a storage device such as a server, and is input into a computer as teaching data for machine learning, and the machine learning is performed to determine the specific position (blocked position) where the blockage or narrowing occurs. The blockage inference unit 16 stores a learning model (e.g., a program) obtained by the above-mentioned machine learning, and uses the learning model to infer any blockage position that will occur within a predetermined time from time T1 based on the pressure changes and flow rates detected by the pressure sensors (S1 to S3) and the flow rate detection unit E (i.e., if the blood purification treatment is continued, the blockage position that will occur at time T0 is inferred).

[0113] In addition, according to the present embodiment, the occlusion inference unit 16 uses the teaching data generated by the pressure changes and flow rate detected by the pressure sensors (S1-S3) and the flow rate detection unit E during the priming or blood purification treatment to learn whether the pressure changes and flow rate detected by the pressure sensors (S1-S3) and the flow rate detection unit E are within a predetermined range, and infers the occlusion position that will occur within a predetermined time period (time T0) based on the changes in pressure and flow rate detected by the pressure sensors (S1-S3) and the flow rate detection unit E up to the current time T1.

[0114] The blood return notification unit 17 is an output device that is electrically connected to the occlusion inference unit 16, and provides information on the start of blood return if the occlusion inference unit 16 infers that an occlusion position occurs within a predetermined period of time. The blood return notification unit 17 is any of the following, for example: a display device, such as a display, for displaying an image prompting the start of blood return; an output device, such as a speaker, for outputting a sound prompting the start of blood return; a lighting device, such as an LED, for emitting light or flashing to prompt the start of blood return; and the like.

[0115] For example, if the occlusion inference unit 16 infers that an occlusion position occurs within a predetermined time period or at time T0, the blood return notification unit 17 can provide information to end the current blood purification treatment and perform blood return, and can further provide information on the remaining time (time period from current time T1 to time T0) before the flow path is inferred to be occluded or narrowed. The information on performing blood return can be provided as information on how to control the operation of any pump including the blood pump P1 (flow rate when blood returns).

[0116] If the blood return notification unit 17 provides information for starting blood return, the blood return operation can be performed on the operation unit 14. For example, the operation of opening or closing the clamping portion V1 and the operation of starting or stopping the relevant pump can be performed on the operation unit 14. For example, if the blood return notification unit 17 provides information for starting blood return, the blood pump P1 can be started in a state where the clamping portion V3 is opened but the clamping portion V1 is closed. Therefore, the replacement fluid (physiological saline) is supplied through the physiological saline supply line La, thereby replacing the blood in the blood circuit 1 and achieving blood return.

[0117] The execution unit 15 is used to start blood return. Fig.18 The execution unit 15 is a microcomputer or the like, which is electrically connected to the operation unit 14, the blood pump P1, the first substitution pump P3, the substitution fluid transfer pump P6, and the second substitution pump P8. If the operator performs a predetermined operation according to the information provided by the blood return notification unit 17, the execution unit 15 opens the substitution fluid supply line to start blood return.

[0118] Or, refer to Fig.19 , the execution unit 15 may be a microcomputer or the like, which is electrically connected to the occlusion inference unit 16, the blood pump P1 and the replacement pump (the first replacement pump P3, the replacement fluid transfer pump P6 and the second replacement pump P8), and may be configured to automatically switch to blood return if the occlusion inference unit 16 infers that an occlusion position has occurred within a predetermined time period. In this case, if the occlusion inference unit 16 infers that a flow path occlusion or narrowing may occur within a predetermined time period, the priming or blood purification treatment is automatically terminated. Then, with the supply of the replacement fluid, the blood return automatically starts.

[0119] According to the first to third embodiments described above, the replacement fluid supply line is switched from one of the replacement fluid supply line on the blood removal side (physiological saline supply line La) and the replacement fluid supply line on the blood return side (pre-replacement line L2c or post-replacement line L2d) to the other, so that even if the blood flow path is blocked or narrowed when the blood returns, the blood remaining in the blood circuit 1 can be smoothly returned to the patient's body without reconnecting the replacement fluid supply line when the blood returns.

[0120] In particular, the first embodiment adopts the notification unit 9, which is configured to notify the operator to switch the replacement fluid supply line when the determination unit 8 determines that the replacement fluid supply line is switched from one of the blood extraction side replacement fluid supply line (physiological saline supply line La) and the blood return side replacement fluid supply line (front replacement line L2c or rear replacement line L2d). Therefore, it is possible to prompt the operator to switch the replacement fluid supply line according to the determination of the determination unit 8.

[0121] The second embodiment adopts the control unit 11, which is configured to automatically switch the replacement fluid supply line when the determination unit 8 determines that the replacement fluid supply line is switched from one of the blood removal side replacement fluid supply line (physiological saline supply line La) and the blood return side replacement fluid supply line (front replacement line L2c or rear replacement line L2d) to the other. Therefore, the switching of the replacement fluid supply line can be automatically performed according to the determination of the determination unit 8.

[0122] According to the first and second embodiments, when the occlusion recognition unit 7 recognizes that the occlusion position is at the upstream position (position between the distal end E1 of the blood circuit 1a on the blood extraction side and the installation position E3 of the blood pump P1), the determination unit 8 determines to switch from the blood extraction side replacement fluid supply line (physiological saline supply line La) to the blood return side replacement fluid supply line (front replacement line L2c or rear replacement line L2d) to supply replacement fluid when blood is returned. Therefore, blood return can be performed without reversing the blood pump P1.

[0123] According to the first and second embodiments, the blood return side replacement fluid supply line includes a plurality of pipelines connected to the blood return side portion of the blood circuit 1. In addition, the blood purification device includes a first pressure sensor S1 configured to detect the pressure at the blood removal side position of the blood circuit 1, and a second pressure sensor S2 and a third pressure sensor S3 configured to detect the pressure of the blood removal side and the blood return side of the dialyzer 2 at the corresponding blood return side position of the blood circuit 1, respectively. Any occluded position is identified according to the pressure detected by the first pressure sensor S1, the second pressure sensor S2, and the third pressure sensor S3, and the blood removal side replacement fluid supply line is switched to any one of the blood return side replacement fluid supply lines (front replacement line L2c or rear replacement line L2d) to supply replacement fluid. Therefore, any occluded position can be accurately identified according to the pressure detected by the pressure portion.

[0124] According to the first and second embodiments, the blood return side replacement fluid supply line includes a front replacement line L2c connected to the blood extraction side blood circuit 1a and allowing the replacement fluid to be supplied therethrough, and a rear replacement line L2d connected to the blood return side blood circuit 1b and allowing the replacement fluid to be supplied therethrough. In addition, the determination unit 8 is configured to determine whether to switch from the blood extraction side replacement fluid supply line (physiological saline supply line La) to the front replacement line L2c or the rear replacement line L2d to supply the replacement fluid. Therefore, the replacement fluid can be supplied using the front replacement line L2c or the rear replacement line L2d for performing the front replacement or the rear replacement during treatment.

[0125] The first and second embodiments use a peristaltic substitution pump (second substitution pump P8) configured to supply substitution fluid to the blood circuit 1 through the front substitution line L2c or the rear substitution line L2d, so that the amount of substitution fluid supplied when the blood is returned can be accurately grasped, and the completion time of the blood return can be accurately grasped.

[0126] According to the third embodiment, using a learning model obtained by machine learning, any occlusion position is identified based on the pressure change and flow rate detected by the pressure sensors (S1 to S3) and by the flow rate detection section E. Therefore, any occlusion position can be accurately identified using the learning model. According to the fourth embodiment, using a learning model obtained by machine learning, any occlusion position that will occur within a predetermined time period is inferred based on the pressure change and flow rate detected by the pressure sensors (S1 to S3) and by the flow rate detection section E. Therefore, possible occlusion or stenosis can be accurately inferred using the learning model.

[0127] Although several embodiments have been described above, the present invention is not limited thereto. The replacement fluid supply line on the blood removal side may be a supply line different from the physiological saline supply line La. For example, the replacement fluid supply line on the blood removal side may be a supply line branched from the second dialysate introduction line L1b and connected to the connection position E2 (in this case, the replacement fluid for blood return is dialysate), or a supply line branched from the second replacement line L2b and connected to the connection position E2 (in this case, the replacement fluid for blood return is supplemental fluid).

[0128] Although the blood return side replacement fluid supply line according to the above-mentioned embodiment is composed of the front replacement line L2c and the rear replacement line L2d, the blood return side replacement fluid supply line can also be a supply line different from it (but a supply line connected to the downstream position), and can be composed of a single line or more than three lines. That is, the second dialysate introduction line L1b or the first drainage discharge line L3a connected to the dialyzer 2 (blood purifier) ​​can be used as the blood return side replacement fluid supply line. In this case, the dialysate as the replacement fluid is supplied from the dialysate flow path to the blood flow path in the dialyzer 2 by reverse filtration.

[0129] According to the above embodiment, if the occlusion recognition unit 7 recognizes the occlusion position at the upstream position, the determination unit 8 determines to switch from the blood extraction side replacement fluid supply line to the blood return side replacement fluid supply line when the blood returns to supply the replacement fluid. Alternatively, if the occlusion recognition unit 7 recognizes the occlusion position at the downstream position, the determination unit 8 may determine to switch from the blood return side replacement fluid supply line to the blood extraction side replacement fluid supply line when the blood returns to supply the replacement fluid.

[0130] Although the above embodiment is applicable to a dialysis device for continuous renal replacement therapy (CRRT), the above embodiment is also applicable to other devices, such as a dialysis device for patients with chronic renal failure, and a blood separation device configured to remove specific components from blood. In addition, the replacement fluid used when the blood is returned is not limited to physiological saline, dialysate, and supplementary fluid, and may be other fluids (liquids containing electrolytes) suitable for performing replacement when the blood is returned.

[0131] Industrial Applicability

[0132] The present invention can also be applied to any blood purification device having different appearance or additional functions within the spirit of the present invention.

[0133] Reference numerals list

[0134] 1. Blood Circuit

[0135] 1a Blood circuit on the blood extraction side

[0136] 1b Blood return side blood circuit

[0137] 2 Dialyzer (blood purifier)

[0138] 3 Air Trap Chamber

[0139] 4Weighing device

[0140] 5. Heating Pack

[0141] 6 Air Trap Chamber

[0142] 7 Occlusion Recognition Unit

[0143] 8. Judgment Department

[0144] 9 Notification Department

[0145] 10 Operation section

[0146] 11. Control Unit

[0147] 12 Blockage position recognition unit

[0148] 13 Switch notification section

[0149] 14 Operation section

[0150] 15 Executive Department

[0151] 16 Occlusion Inference Unit

[0152] 17 Blood Return Notification Department

[0153] K1 Replenishment Temporary Chamber

[0154] K2 Dialysis Fluid Temporary Room

[0155] K3 Temporary drainage room

[0156] B1 Dialysis Fluid Bag

[0157] B2 Replenishment Bag

[0158] B3 Saline Bag

[0159] L1a First dialysate inlet line

[0160] L1b Second dialysate inlet line

[0161] L2a First replacement pipeline

[0162] L2b Second replacement pipeline

[0163] L2c front replacement line (blood return side replacement fluid supply line)

[0164] L2d post-replacement line (blood return side replacement fluid supply line)

[0165] L3a First liquid discharge line

[0166] L3b Second drain line

[0167] La physiological saline supply line (blood removal side replacement fluid supply line)

[0168] P1 Blood Pump

[0169] P2 Dialysate Inlet Pump

[0170] P3 First displacement pump

[0171] P4 Liquid Discharge Pump

[0172] P5 Dialysate Transfer Pump

[0173] P6 Substitution Fluid Transfer Pump

[0174] P7 Liquid Transfer Pump

[0175] P8 Second displacement pump

[0176] H1 Heating unit

[0177] H2 Heating Device

[0178] S1 First pressure sensor (first detection unit)

[0179] S2 Second pressure sensor (second detection unit)

[0180] S3 Third pressure sensor (third detection unit)

[0181] Pa, Pb pressure sensor

[0182] V1 to V3 clamping section

[0183] E flow rate detection unit.

Claims

1. A blood purification device, comprising: a blood circuit, comprising a blood extraction side blood circuit for extracting blood from a patient and a blood return side blood circuit for returning blood to the patient, the patient's blood circulates extracorporeally through the blood circuit, a blood purifier connected to the blood extraction side blood circuit and the blood return side blood circuit, the blood purifier being configured to purify blood; a blood pump disposed on the blood circuit and configured to allow the patient's blood to circulate extracorporeally through the blood circuit; A replacement fluid supply line on the blood withdrawal side, which is connected to the blood circuit, and when the blood returns, the replacement fluid is supplied to the blood circuit through the replacement fluid supply line on the blood withdrawal side; a blood return side replacement fluid supply line connected to the blood circuit or the blood purifier, and supplying replacement fluid to the blood circuit through the blood return side replacement fluid supply line when the blood is returned, the blood circuit being located on the blood return side relative to the portion connected to the blood removal side replacement fluid supply line; and The control unit is configured to switch the replacement fluid supply line from one of the blood extraction side replacement fluid supply line and the blood return side replacement fluid supply line to the other.

2. The blood purification device according to claim 1, further comprising a notification unit, the notification unit being configured to provide information on switching the replacement fluid supply line if it is determined that the replacement fluid supply line is switched from one of the blood removal side replacement fluid supply line and the blood return side replacement fluid supply line to the other, wherein: If the operator performs a predetermined operation based on the information provided by the notification unit, the control unit switches the replacement fluid supply line from one of the blood removal side replacement fluid supply line and the blood return side replacement fluid supply line to the other.

3. The blood purification device according to claim 1, wherein: If it is determined that the replacement fluid supply pipeline is switched from one of the blood withdrawal side replacement fluid supply pipeline and the blood return side replacement fluid supply pipeline to the other, the control unit automatically switches the replacement fluid supply pipeline from one of the blood withdrawal side replacement fluid supply pipeline and the blood return side replacement fluid supply pipeline to the other.

4. The blood purification device according to any one of claims 1 to 3, further comprising an occlusion identification unit configured to identify any occlusion position of the blood flow path, wherein: If the occlusion identifying unit identifies that the occlusion position is at the blood extraction side position of the blood circuit, it determines to switch from the blood extraction side replacement fluid supply line to the blood return side replacement fluid supply line to supply replacement fluid when blood returns.

5. The blood purification device according to claim 4, wherein: The blood return side replacement fluid supply line includes a plurality of pipelines connected to the blood return side portion of the blood circuit, wherein the blood purification device further includes: a first pressure sensor configured to detect the pressure at the blood withdrawal side position of the blood circuit; and a second pressure sensor and a third pressure sensor configured to respectively detect the pressures on the blood withdrawal side and blood return side of the blood purifier at each blood return side position of the blood circuit, wherein any occluded position is identified based on the pressure detected by the first pressure sensor, the second pressure sensor and the third pressure sensor, and wherein it is determined to switch from the blood withdrawal side replacement fluid supply line to the blood return side replacement fluid supply line to supply replacement fluid.

6. The blood purification device according to claim 5, wherein: The blood return side replacement fluid supply pipeline includes: a front replacement pipeline, which is connected to the blood extraction side blood circuit and allows replacement fluid to be supplied therethrough; and a rear replacement pipeline, which is connected to the blood return side blood circuit and allows replacement fluid to be supplied therethrough, and wherein it is determined that the replacement fluid supply pipeline on the blood extraction side is switched to the front replacement pipeline or the rear replacement pipeline to supply the replacement fluid.

7. The blood purification device according to claim 6, further comprising a peristaltic substitution pump, wherein the peristaltic substitution pump is configured to supply substitution fluid to the blood circuit through the front substitution line or the rear substitution line.

8. A blood purification device, comprising: a blood circuit, comprising a blood extraction side blood circuit for extracting blood from a patient and a blood return side blood circuit for returning blood to the patient, the patient's blood circulates extracorporeally through the blood circuit, a blood purifier connected to the blood extraction side blood circuit and the blood return side blood circuit, the blood purifier being configured to purify blood; a blood pump disposed on the blood circuit and configured to allow the patient's blood to circulate extracorporeally through the blood circuit; A replacement fluid supply line on the blood withdrawal side, which is connected to the blood circuit, and when the blood returns, the replacement fluid is supplied to the blood circuit through the replacement fluid supply line on the blood withdrawal side; a blood return side replacement fluid supply pipeline connected to the blood circuit or the blood purifier, and when the blood is returned, the replacement fluid is supplied to the blood circuit through the blood return side replacement fluid supply pipeline, and the position of the blood circuit is located on the blood return side relative to the part connected to the blood removal side replacement fluid supply pipeline; a pressure sensor configured to detect pressure in a flow path at a specific location of the blood circuit; a flow velocity detection unit configured to detect a flow velocity in a flow path at a specific position of the blood circuit; as well as An occlusion position identification section is configured to identify any occlusion position based on the pressure change and flow velocity detected by the pressure sensor and by the flow velocity detection section by using a learning model obtained by machine learning, wherein a plurality of data of pressure change and flow velocity when occlusion or narrowing occurs in the flow path in the blood circuit are accumulated to generate accumulated data, the accumulated data serving as teaching data for identifying the occlusion position of the flow path.

9. The blood purification device according to claim 8, wherein: The occlusion position identification unit uses a learning model to identify the occlusion position based on the pressure change and flow rate detected by the pressure sensor and the flow rate detection unit, and determines to switch to an appropriate replacement fluid supply pipeline when the occlusion position is identified. The learning model is obtained through machine learning, in which not only multiple data on pressure changes and flow rates when occlusion occurs or flow path narrowing occurs in the blood circuit are accumulated, but also multiple data indicating switching to an appropriate replacement fluid supply pipeline when the occlusion position is identified are accumulated, thereby generating accumulated data, which serves as teaching data for identifying the occlusion position and switching to an appropriate replacement fluid supply pipeline when the occlusion position is identified.

10. The blood purification device according to claim 9, characterized in that: Also includes: an execution unit configured to switch the replacement fluid supply line from one of the blood removal side replacement fluid supply line and the blood return side replacement fluid supply line to the other; and A switching notification unit is configured to provide information to switch to the one replacement fluid supply line determined to be appropriate, and to provide the information if the blocked position recognition unit recognizes the blocked position and determines to switch to the one replacement fluid supply line that is appropriate.

11. The blood purification device according to claim 9, further comprising an execution unit configured to switch the replacement fluid supply line from one of the blood extraction side replacement fluid supply line and the blood return side replacement fluid supply line to the other, wherein: If the blocked position recognition unit recognizes the blocked position and determines that the replacement fluid supply line is switched to an appropriate replacement fluid supply line, the execution unit automatically switches the replacement fluid supply line to the replacement fluid supply line determined to be appropriate.

12. A blood purification device, comprising: a blood circuit, comprising a blood extraction side blood circuit for extracting blood from a patient and a blood return side blood circuit for returning blood to the patient, the patient's blood circulates extracorporeally through the blood circuit, a blood purifier connected to the blood extraction side blood circuit and the blood return side blood circuit, the blood purifier being configured to purify blood; a blood pump disposed on the blood circuit and configured to allow the patient's blood to circulate extracorporeally through the blood circuit; a pressure sensor configured to detect pressure in a flow path at a specific location of the blood circuit; a flow velocity detection unit configured to detect a flow velocity in a flow path at a specific position of the blood circuit; as well as An occlusion inference section is configured to infer any occlusion position that will occur within a predetermined period of time based on the pressure change and flow velocity detected by the pressure sensor and the flow velocity detection section by using a learning model obtained by machine learning, wherein a plurality of data of pressure change and flow velocity when occlusion or narrowing occurs in the flow path in the blood circuit are accumulated to generate accumulated data, the accumulated data serving as teaching data for identifying the occlusion position of the flow path.

13. The blood purification device according to claim 12, wherein: The occlusion inference unit utilizes the teaching data generated by the pressure sensor and the pressure changes and flow rate detected by the flow rate detection unit during the pre-filling or blood purification treatment process to learn whether the pressure changes and flow rate detected by the pressure sensor and the flow rate detection unit are within a predetermined range, and infers the occlusion position that will occur within a predetermined time period based on the pressure changes and flow rate detected by the pressure sensor and the flow rate detection unit up to the current time.

14. The blood purification device according to claim 12 or 13, further comprising: an actuator configured to initiate blood return; The blood return notification section is configured to provide information for starting blood return if the occlusion position is estimated by the occlusion estimation section to occur within a predetermined period of time.

15. The blood purification device according to claim 14, wherein: If the occlusion estimating section estimates that the occlusion position occurs within a predetermined period of time, the blood return notifying section provides information on the remaining time until the flow path is occluded or narrowed.

16. The blood purification device according to claim 12 or 13, further comprising an execution unit configured to start blood return, wherein: If the occlusion estimating unit estimates that an occlusion position occurs within a predetermined time, the executing unit automatically starts blood return.

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