Blood purification device and blood purification circuit

Abstract

To reduce the volume of blood circulating extracorporeally while ensuring safety in blood purification therapy. [Solution] The device comprises an arterial clamp capable of opening and closing the blood flow path of the arterial blood circuit to which an arterial blood circuit can be attached, a venous clamp capable of opening and closing the blood flow path of the venous blood circuit to which a venous blood circuit can be attached, a pump capable of introducing or releasing air into a gas circuit, a processing unit that controls the pump, the arterial clamp, and the venous clamp and alternately performs a blood withdrawal process by introducing the gas into the branching point and a blood return process by releasing the gas from the branching point, and a pressure measuring unit provided only in the gas circuit among the arterial blood circuit, the venous blood circuit, and the gas circuit, or provided only in the branching point.

Description

Technical Field

[0001] The present disclosure relates to a blood purification device that performs blood purification treatment while extracorporeally circulating a patient's blood, and a blood purification circuit used therefor.

Background Art

[0002] Conventionally, as an example of treatment by blood purification, dialysis treatment using a blood purification device having a dialyzer and a blood circuit is known. In this dialysis treatment, while the blood taken out from the patient is extracorporeally circulated by the blood circuit, blood purification is performed using a dialyzer connected to the blood circuit, and the treated blood is returned to the patient's body. Previously, patients who required dialysis treatment were adults with reduced kidney function, but in recent years, newborns and children have also become targets.

[0003] Regarding such blood purification, in order to ensure the safety of the patient, the amount of blood that can be taken out of the body at one time is determined according to the patient's weight and the like. For this reason, for adults with relatively large body weights, the blood flow rate is generally set to about 200 ml / min. On the other hand, for newborns and children with very small body weights compared to adults, depending on their body weights, the blood flow rate needs to be set to 100 ml / min or less. Also, even in the case of adults, depending on the patient's condition, a low blood flow rate of 100 ml / min or less may be set.

[0004] In order to enable such blood purification treatment according to body weight, for example, Patent Document 1 discloses calculating the blood flow rate based on the input patient's body weight. Also, in order to enable blood purification treatment with a low flow rate as described above, for example, Patent Document 2 discloses using a tube for children with a smaller inner diameter than a tube for adult treatment. Further, Patent Document contains a blood purification column for children with a blood volume of 10 ml or less.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2023-119259 [Patent Document 2] Patent No. 5525874 [Patent Document 3] Patent No. 5870920 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] However, simply miniaturizing the individual components of the blood purification device was insufficient to adequately reduce the extracorporeal blood volume due to the presence of other components in the device. Furthermore, in blood purification devices such as those described in Patent Documents 1 and 2, the presence of pressure measuring units on the blood circuit limited the reduction in extracorporeal blood volume. In addition, from the standpoint of ensuring safety in blood purification therapy, it was necessary to install pressure measuring units in multiple locations, which resulted in time-consuming installation and preparation of these units.

[0007] This disclosure has been made in view of these issues, and its purpose is to provide a blood purification device and a blood purification circuit that can ensure safety in blood purification therapy while reducing the volume of extracorporeal blood circulation. [Means for solving the problem]

[0008] According to one aspect of the present disclosure, a blood purification device comprising: a blood purifier for purifying a patient's blood; an arterial blood circuit which serves as a blood flow path for introducing the blood withdrawn from the patient into the blood purifier; a venous blood circuit which serves as a blood flow path from the blood purifier to the patient; and a gas circuit connected to a branching point that branches either the arterial blood circuit or the venous blood circuit, which serves as a flow path for air, wherein the device includes an arterial clamp capable of opening and closing the blood flow path of the arterial blood circuit to which the arterial blood circuit is attached, and the venous blood circuit is attached A blood purification device is provided, comprising: a venous clamp capable of opening and closing the blood flow path of the venous blood circuit to be cut; a pump capable of introducing or releasing air into the gas circuit; a processing unit that controls the pump, the arterial clamp, and the venous clamp, and alternately performs blood removal by introducing the gas into the branching point and blood return by releasing the gas from the branching point; and a pressure measuring unit provided only in the gas circuit among the arterial blood circuit, the venous blood circuit, and the gas circuit, or provided only in the branching point.

[0009] According to one aspect of the present disclosure, a blood purification circuit is provided that is connected to a blood purifier for purifying a patient's blood, comprising: an arterial blood circuit which serves as a blood flow path for introducing the blood withdrawn from the patient into the blood purifier; a venous blood circuit which serves as a blood flow path from the blood purifier to the patient; a gas circuit which serves as an air flow path and is connected to a branching section that branches off either the arterial blood circuit or the venous blood circuit; and a pressure measuring section which is provided only in the gas circuit among the arterial blood circuit, the venous blood circuit, and the gas circuit, or which is provided only in the branching section. [Effects of the Invention]

[0010] According to this disclosure, it is possible to provide a blood purification device and a blood purification circuit that can ensure safety in blood purification while reducing the volume of extracorporeal blood circulation.

[0011] The effects described above are merely illustrative for the sake of explanation, and the effects relating to this disclosure are not limited to those described above. In addition to the effects described above, any other effects described herein may be achieved. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram showing an example of the usage state of the blood purification device according to the first embodiment. [Figure 2] This is a block diagram showing the electrical configuration of a blood purification device according to the first embodiment. [Figure 3] This is a diagram showing the configuration of the extracorporeal circulation section of the blood purification device according to the first embodiment. [Figure 4] This is a functional block diagram of a blood purification device according to the first embodiment. [Figure 5] This is a flowchart showing the treatment flow in the blood purification device according to the first embodiment. [Figure 6] This is a diagram showing the configuration of the extracorporeal circulation section during blood withdrawal in a blood purification device according to the first embodiment. [Figure 7] This is a diagram showing the configuration of the extracorporeal circulation section during blood return in the blood purification device according to the first embodiment. [Figure 8] This is a flowchart showing the process of stopping treatment in a blood purification device according to the first embodiment. [Figure 9] This is a diagram showing the configuration of the extracorporeal circulation section of the blood purification device according to the first embodiment when treatment is stopped. [Figure 10] This is a diagram showing the configuration of the extracorporeal circulation section of a blood purification device according to a modified example of the first embodiment. [Figure 11] This is a diagram showing the configuration of the extracorporeal circulation section of a blood purification device according to the second embodiment. [Modes for carrying out the invention]

[0013] Hereinafter, the blood purification device and blood purification circuit of the present disclosure will be described in detail while referring to the drawings. Note that the present disclosure is not limited to the content described below, and can be arbitrarily modified and implemented within the scope of not changing its gist. In addition, the drawings used in each embodiment schematically show the blood purification device according to the present disclosure, and partial emphasis, enlargement, reduction, or omission, etc. are performed to deepen the understanding, and the scale, shape, etc. of each component may not accurately represent the actual situation. Furthermore, some numerical values used in each embodiment are all examples, and can be variously changed as necessary. And for the components common in the drawings, the same reference numerals are attached.

[0014] <First Embodiment> (Configuration of Blood Purification Device) First, while referring to FIGS. 1 to 4, the configuration of the blood purification device and blood purification circuit of the present disclosure will be described. FIG. 1 is a schematic diagram showing an example of the usage state of the blood purification device according to the present embodiment. FIG. 2 is a block diagram showing the electrical configuration of the blood purification device according to the present embodiment. FIG. 3 is a configuration diagram of the extracorporeal circulation part of the blood purification device according to the present embodiment. FIG. 4 is a functional block diagram of the blood purification device according to the first embodiment.

[0015] As shown in FIG. 1, the blood purification device 1 is composed of a dialysis device for performing dialysis treatment on patient H. Specifically, the blood purification device 1 has a main body 3 installed on a base unit 2, a display 4 connected to the upper part of the main body 3, and a blood purifier 5 installed on the side of the main body 3. Further, the main body 3 of the blood purification device 1 has a processing unit 6 for processing various information and data, an internal piping unit 7 for circulating dialysis fluid between the blood purifier 5, and an extracorporeal circulation unit 8 for circulating the blood, which is the body fluid of patient H, outside the body. With such a configuration, the blood purification device 1 can take out the blood of patient H outside the body (blood withdrawal treatment), remove unnecessary or toxic substances or moisture from the blood in the blood purifier 5 (blood purification treatment), and return the purified blood to patient H (blood return treatment). Here, the extracorporeal circulation unit 8 constitutes a circuit for purifying blood, which corresponds to the blood purification circuit in the present disclosure. Note that the blood purification device 1 is composed of a device base 1a including the main body 3, the display 4, the processing unit 6, and the internal piping unit 7, and a consumable unit 1b including the blood purifier 5 and the extracorporeal circulation unit 8.

[0016] The base unit 2 is composed of a plate-shaped base 2a connected to the bottom of the main body 3 and four casters 2b installed on the base 2a. This enables the easy movement of the blood purification device 1. Note that the number of casters 2b is not limited to four, and may be three or five or more as long as the blood purification device 1 can be moved.

[0017] The main body 3 is composed of a substantially rectangular parallelepiped housing. Further, various component devices and various components constituting the internal piping unit 7 and the extracorporeal circulation unit 8 of the blood purification device 1 are arranged inside and on the surface of the main body 3. For example, as the component devices, there may be various pumps and detectors, and as the components, there may be a blood circuit, a dialysis fluid circuit, and various sensors.

[0018] As shown in Figure 2, the blood purification device 1 consists of a display 4, a processing unit 6, an internal piping unit 7, and an extracorporeal circulation unit 8, all of which are electrically connected to each other via control lines and data lines. This allows the blood purification device 1 to transmit and receive various signals, data, and information, as well as to perform various controls via the processing unit 6. In the following, "data" is generally assumed to consist of numerical values, symbols, or characters that have been processed from signals, etc. "Information" is generally assumed to be collected or processed data, for example, content that the receiving side can use as material for further consideration or that can be utilized by the receiving side. However, data and information may be used in ways that do not conform to the above assumptions, depending on their content and the surrounding context.

[0019] When treating a patient using the blood purification device 1 and blood purifier 5, the process proceeds in the order of pre-process, treatment process, and post-process. The pre-process is a predetermined preparation process performed before the treatment process, and specifically involves priming, gas purging, and initial blood removal. Priming is the process of washing, removing air bubbles, and filling the blood side of the blood circuit and blood purifier 5 that constitute the extracorporeal circulation unit 8 with priming fluid. Gas purging is the process of washing, removing air bubbles, and filling the dialysate side of the blood purifier 5 with liquid. Furthermore, initial blood removal is the process of taking blood from patient H and replacing the priming fluid filling the blood circuit and blood purifier 5 with the blood.

[0020] In the treatment process, the following steps are performed: blood collection from the patient (blood withdrawal), purification of the patient's blood by a blood purifier 5 (blood purification), and return of the purified blood to the patient (blood return). In this embodiment, the blood withdrawal and blood return processes are performed alternately.

[0021] The post-treatment process is a procedure performed after the treatment phase to complete the patient's treatment, and specifically involves final blood return. Final blood return is the process of returning any blood remaining in the blood purifier 5 and blood circuit to the patient after the completion of treatment.

[0022] In this embodiment, a hemodialysis machine is described as an example of the blood purification device 1, but it is not limited to this. For example, a device for acute blood purification, a peritoneal dialysis machine, an ultrafiltration machine, or a hemofiltration machine can also be an example of the blood purification device 1.

[0023] Furthermore, in addition to the above-described configuration, the blood purification device 1 may also have a communication unit that enables the transmission and reception of information with external devices such as terminal devices or server devices. This allows the blood purification device 1 to acquire various types of patient information (patient information) from the external device via the communication unit.

[0024] The blood purification device 1 of this embodiment is configured to perform treatment even when the blood flow rate during blood withdrawal and blood return is 50 ml / min or less, particularly 15 ml / min or less, and even 3 ml / min or less. Therefore, the blood purification device 1 of this embodiment can appropriately treat neonatal or pediatric patients, but it is not limited to patients. For example, even in adult patients, if the renal disease is in its early stages, the blood flow rate may be set to 50 ml / min or less. Naturally, the blood purification device 1 of this embodiment can also perform treatment when the blood flow rate is 50 ml / min or more, and can handle ranges such as 100 ml / min or more and 600 ml / min or less. The reason why it can handle such a wide range of blood flow rates, from normal to very low, will be explained later.

[0025] 〔display〕 Next, as shown in Figures 1 and 2, the display 4 has an input unit 4a consisting of a touch panel type input interface and an output unit 4b consisting of a general screen type output interface. In other words, the display 4 in this embodiment is a touch panel equipped with an input / output interface. Here, the method for detecting input by the touch panel may be any method, such as capacitive or resistive. Furthermore, the operable area and position on the touch panel can be freely set by the administrator of the blood purification device 1. In other words, the arrangement of the input unit 4a and the output unit 4b on the display 4 can be set as appropriate.

[0026] The input interface may be separated from the display 4. In this case, the blood purification device 1 may be provided with a keyboard equipped with physical key buttons such as a numeric keypad or character input keys, and an input device such as a mouse. Furthermore, if the blood purification device 1 has a communication unit, various types of information may be displayed using the output interface of an external device. In this case, for example, various types of information related to the patient's treatment may be acquired and displayed on a mobile terminal device such as a smartphone or tablet.

[0027] [Blood Purifier] As can be seen from Figures 1 and 3, the blood purifier 5 has blood inlet 5a and blood outlet 5b at both ends of its housing as blood ports, and dialysate inlet 5c and dialysate outlet 5d on the side of its housing as dialysate ports. The arterial blood circuit L1, which will be described later, is connected to the blood inlet 5a, and the venous blood circuit L2, which will be described later, is connected to the blood outlet 5b. In addition, the internal piping section 7 is connected to the dialysate inlet 5c and dialysate outlet 5d via piping for circulating dialysate.

[0028] The blood purifier 5 contains multiple hollow fiber membranes (not shown) inside, and these hollow fibers constitute a blood purifying membrane for purifying blood. Inside the blood purifier 5, a blood channel through which patient H's blood flows and a dialysate channel through which dialysate flows are formed. Furthermore, the hollow fiber membrane constituting the blood purifying membrane has numerous minute pores that penetrate its outer and inner surfaces, and is configured so that impurities in the blood can permeate into the dialysate through the hollow fiber membrane.

[0029] Furthermore, the blood purifier 5 is not limited to a dialyzer having the configuration described above. For example, it may be an adsorption-type blood purifier used for endotoxin adsorption therapy, activated carbon adsorption therapy, or bilirubin adsorption therapy. Also, the blood purifier 5 may be a hemodiafilter.

[0030] [Internal piping section] The internal piping section 7 is located inside the main body 3 and is connected via piping to two dialysate inlets 5c and dialysate outlets 5d located on the side of the blood purifier 5. For example, the internal piping section 7 includes various components such as pipes, pumps, valves, sensors, and filters. More specifically, the internal piping section 7 may include a double pump, a water removal pump, a degassing pump, a pressure pump, a pressure reducing valve, a solenoid valve, a temperature sensor, a pressure sensor, and a chemical filter. Furthermore, flexible materials such as polyvinyl chloride tubing or silicone tubing may be used for the piping.

[0031] The internal piping section 7 is assembled by appropriately selecting the above-mentioned components according to the piping configuration and type, and is structured to enable the circulation and cleaning of dialysate. Furthermore, the internal piping section 7 is structured to enable the introduction and discharge of dialysate to and from the blood purifier 5. Note that these specific configurations are not features of the blood purifier of this disclosure, and therefore their explanation is omitted.

[0032] [Extracorporeal circulation department] Next, as shown in Figure 3, the extracorporeal circulation unit 8, which is a blood purification circuit, has three circuits: an arterial blood circuit L1, a venous blood circuit L2, and a gas circuit L3, and a branching section 23 connecting the venous blood circuit L2 and the gas circuit L3. Here, the arterial blood circuit L1 is a circuit that introduces blood drawn from patient H into the blood purifier 5, and the venous blood circuit L2 is a circuit that returns the blood purified by the blood purifier 5 to patient H. The arterial blood circuit L1 and the venous blood circuit L2 constitute the blood circuit through which the patient's blood flows. The gas circuit L3 is a circuit that introduces gas into the branching section 23 and leads gas out from the branching section 23.

[0033] As can be seen in Figure 3, one end of the arterial blood circuit L1 is connected to a single needle 22 inserted into the arm of patient H via a Y-shaped tube 21, and the other end is connected to the blood inlet 5a of the blood purifier 5. Here, the Y-shaped tube 21 has the needle 22 connected to one end, and the other end is branched into two, to which the arterial blood circuit L1 is connected via a connector (not shown).

[0034] Furthermore, the arterial blood circuit L1 is attached to an arterial clamp V1 provided on the base 1a side of the blood purification device 1. The arterial clamp V1 is composed of a solenoid valve and operates in accordance with a drive signal received from the processing unit 6, opening and closing the flow path of the arterial blood circuit L1. This opening and closing operation of the arterial clamp V1 allows control of the process of drawing blood from patient H and introducing it into the blood purifier 5.

[0035] As can be seen in Figure 3, one end of the venous blood circuit L2 is connected to a single puncture needle 22 inserted into the patient H's arm via a Y-shaped tube 21, and the other end is connected to the blood outlet 5b of the blood purifier 5. Here, the other branched end of the Y-shaped tube 21, to which the arterial blood circuit L1 is not connected, is connected to the venous blood circuit L2 via a connector (not shown).

[0036] Furthermore, the venous blood circuit L2 is attached to a venous clamp V2 provided on the base 1a side of the blood purification device 1. The venous clamp V2 is composed of a solenoid valve and operates in accordance with a drive signal received from the processing unit 6, opening and closing the flow path of the venous blood circuit L2. This opening and closing operation of the venous clamp V2 allows control of the blood return process, which returns blood to the patient H.

[0037] Furthermore, a branch section 23 is provided in the venous blood circuit L2. Specifically, the branch section 23 is located between the blood purifier 5 and the venous clamp V2. The branch section 23 consists of a chamber capable of storing blood and gas. The branch section 23 has a shape that extends in the vertical direction. The venous blood circuit L2 extending from the blood outlet 5b of the blood purifier 5 is connected to the side of the branch section 23, and the venous blood circuit L2 extending to the Y-tube 21 via the venous clamp V2 is connected to the bottom of the branch section 23, which is located vertically downwards. In addition, one end of the gas circuit L3 is connected to the top of the branch section 23, which is located vertically upwards.

[0038] Due to the structure of the branching section 23, blood purified by the blood purifier 5 can be introduced from the side of the branching section 23, and the introduced blood is temporarily stored in the branching section 23. The stored blood can also be led out to the venous blood circuit L2 from the bottom of the branching section 23. Details of the introduction and exit of blood in the branching section 23 will be described later.

[0039] Furthermore, a liquid level detection unit 24 is provided around the branching section 23 to detect the liquid level of the blood stored in the branching section 23. The liquid level detection unit 24 consists of oscillating elements 24a, 24b and receiving elements 24c, 24d, which are provided on the side of the branching section 23. Specifically, a pair of oscillating elements 24a and receiving element 24c constitute one sensor, and a pair of oscillating elements 24b and receiving element 24d constitute another sensor, and these two sensors are arranged to be separated vertically. In particular, the oscillating element 24a and receiving element 24c are located vertically above, and the oscillating element 24b and receiving element 24d are located vertically below.

[0040] With this configuration, ultrasonic waves of a predetermined wavelength are emitted from the oscillating elements 24a and 24b toward the receiving elements 24c and 24d, and the presence or absence of blood is determined according to the change in the wavelength or presence or absence of the received ultrasonic waves, thereby detecting the blood level. In particular, when the position of the blood level changes at the branching section 23, it is possible to detect when the liquid level is located at a predetermined height above in the vertical direction, or when the liquid level is located at a predetermined height below in the vertical direction.

[0041] The configuration of the liquid level detection unit 24 is not limited to the sensor consisting of the oscillating element and receiving element described above, but may also be a sensor that images the liquid level of blood, a sensor that detects the liquid level by contacting the blood, a sensor consisting of a light-emitting element and a light-receiving element, etc.

[0042] As can be seen in Figure 3, one end of the gas circuit L3 is connected to the top of the branching section 23, and the other end is open to the atmosphere. A pump P1 is also connected to the gas circuit L3. Furthermore, a pressure measuring section S1 is provided in the gas circuit L3. The pump P1 is driven in both forward (clockwise) and reverse (counterclockwise) directions, enabling the introduction of air into the branching section 23 and the discharge of air from the branching section 23. Specifically, when the pump P1 rotates forward, gaseous air is supplied to the branching section 23, and when the pump P1 rotates reverse, gaseous air is discharged from the branching section 23.

[0043] The amount (speed) of forward and reverse rotation of pump P1 can be controlled by changing the drive signal supplied to the pump. In other words, if the rotation speed of pump P1 increases, the amount of air supplied or discharged increases, and if the rotation speed of pump P1 decreases, the amount of air supplied or discharged decreases.

[0044] The type of pump P1 is not particularly limited, as long as it can introduce air into the branching section 23 and discharge air from the branching section 23. In this embodiment, a peristaltic pump is assumed, but other pumps such as diaphragm pumps may also be used.

[0045] The pressure measuring unit S1 is a known pressure sensor that measures the pressure near the branching section 23. Specifically, when the pump P1 is driven in forward rotation, the pressure measuring unit S1 measures the pressure when air is introduced into the branching section 23, and when the pump P1 is driven in reverse rotation, it measures the pressure when air is discharged from the branching section 23.

[0046] By controlling the introduction and exit of air and the arterial clamp V1 and venous clamp V2, blood withdrawal and blood return processes become possible. Specifically, when the arterial clamp V1 is opened to open the flow path of the arterial blood circuit L1, and the venous clamp V2 is closed to close the flow path of the venous blood circuit L2, air is released from the branching section 23, creating negative pressure inside the branching section 23, and a flow occurs that draws blood towards the side of the branching section 23. As a result, blood is withdrawn from patient H and stored in the branching section 23 via the blood purifier 5. On the other hand, when the arterial clamp V1 is closed to close the flow path of the arterial blood circuit L1, and the venous clamp V2 is opened to open the flow path of the venous blood circuit L2, air is introduced into the branching section 23, creating positive pressure inside the branching section 23, and a flow occurs that pushes blood out from the bottom of the branching section 23. As a result, purified blood is returned to patient H. In other words, by controlling the rotation direction of the pump P1 and the drive of the arterial clamp V1 and venous clamp V2, the blood withdrawal process and the blood return process are performed alternately and repeatedly. During this time, the pressure measuring unit S1 measures the pressure during the blood withdrawal process and the blood return process. Specifically, the pressure measuring unit S1 measures the pressure during the blood withdrawal process when air is discharged, and measures the pressure during the blood return process when air is introduced.

[0047] In this embodiment, the other end of the gas circuit L3 is open to the atmosphere, so air is introduced and discharged as a gas by the pump P1. However, the other end of the gas circuit L3 may be connected to a tank filled with another gas (for example, nitrogen). In this case, the other gas is introduced and discharged to the branching section 23, and the blood removal process and blood return process are performed alternately and repeatedly.

[0048] As described above, in this embodiment, the extracorporeal circulation unit 8, which is a blood purification circuit, has an arterial blood circuit L1, a venous blood circuit L2, a branching section 23, an arterial clamp V1, a venous clamp V2, and a pressure measuring unit S1. Furthermore, in the extracorporeal circulation unit 8, which is a blood purification circuit, the pressure measuring unit S1 is provided only in the gas circuit L3 of the three circuits, and the arterial blood circuit L1 and the venous blood circuit L2, which are blood circuits, are not provided with a pressure measuring unit (pressure sensor). In addition, the installation of devices and components that would increase the extracorporeal circulation blood volume on the blood circuits has been reduced. With this configuration, by controlling the pump P1, arterial clamp V1 and venous clamp V2, blood withdrawal and blood return processing can be performed alternately. Details of this control will be described later.

[0049] [Processing Section] Next, the processing unit 6 according to this embodiment is composed of a processor 6a and a memory 6b, as shown in Figure 2.

[0050] The processor 6a consists of a GPU (Graphics Processing Unit) or a CPU (Central Processing Unit) and functions as a processing unit that controls each component of the blood purification device 1 based on various programs stored in memory 6b. Specifically, the processor 6a reads and executes a program from memory 6b for performing treatment to purify the patient's blood or a program for executing the OS. In particular, the processor 6a determines whether the blood withdrawal and blood return processes of the blood purification device 1 are being performed normally (whether they are in a faulty state), and if it is determined that they are not being performed normally (faulty state), it executes a process to stop the drive of the pump P1 and a process to occlude the arterial clamp V1 and venous clamp V2. The processor 6a may consist of a single GPU or CPU, or it may be composed of a combination of multiple CPUs or GPUs.

[0051] Memory 6b consists of ROM, RAM, non-volatile memory, HDD, etc., and functions as a storage unit. ROM stores instruction commands as a program for performing treatment to purify the patient's blood. It also stores a blood flow table consisting of blood flow information set for each patient H, a pressure value table consisting of pressure value information set for each patient H, and setting information for controlling the pump P1 and each clamp corresponding to the blood flow information and pressure value information. RAM is used for writing and reading data while the program stored in ROM is being processed by processor 6a. Non-volatile memory is a storage device in which data is written and read by the execution of the program, and the data written there is saved even after the execution of the program has finished.

[0052] In particular, in this embodiment, a program is stored for determining whether the blood withdrawal and blood return processes of the blood purification device 1 are in a faulty state. Furthermore, if the determination determines that the blood withdrawal or blood return process is in a faulty state, a program is also stored for stopping the operation of the pump P1 and for occluding the arterial clamp V1 and venous clamp V2.

[0053] Next, with reference to Figure 4, the functional configuration of the processing unit 6 of the blood purification device 1 according to this embodiment will be described. In particular, Figure 4 shows other components of the blood purification device 1 in addition to the processing unit 6, and also describes the flow of information and signals between each device.

[0054] As shown in Figure 4, the processing unit 6 includes an arithmetic unit 61, a pump control unit 62, a clamp control unit 63, and a storage unit 64. Each of these units is realized by the operation of the processor 6a and memory 6b of the processing unit 6 itself, or by the processor 6a reading and executing a program stored in memory 6b.

[0055] As shown in Figure 4, the calculation unit 61 receives patient information of patient H receiving blood purification treatment via the input unit 4a. Here, patient information includes at least weight and includes information such as patient H's name, age, gender, and treatment history. The calculation unit 61 also reads blood flow information and pressure value information stored in the storage unit 64. Here, blood flow information is information related to the blood flow rate during treatment set for each patient H, and is determined in particular based on patient H's weight, condition, and treatment content. Therefore, the blood flow information differs for each patient H and is further updated according to changes in patient H's growth or condition. The pressure value information is information used for comparison with the measured value (pressure value) in the pressure measurement unit S1 and is used to determine whether the blood withdrawal or blood return process of the blood purification device 1 is in a faulty state. The pressure value information is set within a predetermined range as the pressure value at which the blood withdrawal or blood return process is determined to be performing normally (i.e., not in a faulty state). The pressure value information may be determined based on, for example, the type of consumables used in treatment (blood circuit, puncture needle 22, and branch 23, etc.), the patient's condition (weight and blood vessel diameter, etc.), and the treatment content (rotation speed of pump P1, etc.). Therefore, the pressure value information will differ for each patient H, and may also be updated according to changes in patient H's growth or condition.

[0056] As can be seen in Figure 4, the calculation unit 61 reads blood flow information and pressure value information corresponding to the received patient information from the blood flow table and pressure value table stored in the storage unit 64. In other words, the calculation unit 61 identifies patient H from the patient information and extracts blood flow information and pressure value information, which are the setting conditions for patient H's treatment. The calculation unit 61 also generates pump drive information related to the control of pump P1, which is necessary to secure the blood flow, and clamp drive information related to the control of each clamp. More specifically, in the alternating control of blood withdrawal and blood return processing, the calculation unit 61 determines the amount of air introduced and discharged per cycle (1 stroke) of pump P1, and also determines the timing of opening and closing of arterial clamp V1 and venous clamp V2 corresponding to the drive of pump P1. As a result, the calculation unit 61 determines the amount of air introduced and discharged per cycle in the alternating control of blood withdrawal and blood return processing according to the patient H's weight. Furthermore, the calculation unit 61 transmits the generated pump drive information to the pump control unit 62 and the clamp drive information related to the control of each clamp to the clamp control unit 63. The calculation unit 61 then stores the generated pump drive information and clamp drive information as setting information in the storage unit 64.

[0057] Furthermore, the calculation unit 61 continuously or periodically receives pressure signals related to the pressure near the branching section 23 from the pressure measuring unit S1, and calculates a pressure value (measured by the pressure measuring unit S1) based on the received pressure signals. The calculation unit 61 then compares the calculated actual pressure value with a predetermined range of pressure values ​​(pressure value information) read from the storage unit 64 to determine whether the blood removal or blood return process of the blood purification device 1 is in a faulty state. In other words, the calculation unit 61 determines that there is no faulty state if the calculated actual pressure value is within the predetermined range, and determines that there is a faulty state if it is outside the predetermined range. The specific details of the faulty state will be described later.

[0058] As shown in Figure 4, the calculation unit 61 continuously or periodically receives detection signals related to blood level detection in the branching unit 23 from the liquid level detection unit 24. Here, the detection signal is a signal related to ultrasound received by the receiving elements 24c and 24d that constitute the liquid level detection unit 24, and in particular, a signal related to the wavelength of the ultrasound. The calculation unit 61 also determines whether or not blood is present at the position of the sensor consisting of the oscillating element 24a and the receiving element 24c, and also determines whether or not blood is present at the position of the sensor consisting of the oscillating element 24b and the receiving element 24d, based on the received detection signals. Furthermore, the calculation unit 61 determines that the blood level has passed (i.e., a liquid level was present) at the timing when the determination of the presence or absence of blood switches at each sensor. As a result, the calculation unit 61 can calculate the travel time until the liquid level moves from one sensor to the other sensor.

[0059] The calculation unit 61 then compares the calculated actual travel time with the theoretical travel time calculated based on the pump drive information read from the storage unit 64 to determine whether the blood removal or return process of the blood purification device 1 is in a faulty state. Here, the theoretical time is the time determined by the rotational speed of the pump P1 and the discharge or suction amount per rotation. Therefore, the calculation unit 61 can use the rotational speed included in the pump drive information generated for the control of the pump P1 to calculate the theoretical travel time at the time the actual travel time is calculated. Furthermore, the drive state of the pump P1 is expressed by whether or not it is inferior to the originally expected drive of the pump P1. For example, if the pump P1 has deteriorated over time or is malfunctioning from the start, the drive state of the pump P1 will be inferior to the originally expected state.

[0060] Furthermore, since the distance traveled by one of the two sensors provided in the branching section 23 is known in advance, the calculation unit 61 may calculate the actual blood flow velocity in the branching section 23 by subtracting the time it takes for the liquid level to move between the two sensors from the distance between the sensors. In this case, by including information related to the blood flow velocity in the branching section 23 in the setting information or blood flow information, the pump drive information may be determined based on the blood flow velocity instead of the time it takes for the liquid level to move.

[0061] Here, a malfunctioning condition refers to a state in which the blood removal or blood return process of the blood purification device 1 is not being performed normally. For example, this includes a state of poor blood removal, poor blood return, a clogged blood purifier 5, a faulty circuit connection, or a malfunction of the pump P1. Specifically, a malfunctioning condition may include a state of poor blood removal, poor blood return, a clogged blood purifier 5, a faulty circuit connection, a malfunction of the pump P1, and other malfunctions, and the calculation unit 61 may determine these malfunctioning conditions individually. A state of poor blood removal refers to a state in which proper blood removal becomes impossible due to the puncture needle 22 connecting the patient H and the arterial blood circuit L1 coming into contact with the blood vessel wall of the patient H, causing the flow path of the arterial blood circuit L1 to be blocked or narrowed, or due to the arterial blood circuit L1 or the gas circuit L3 being bent. A poor blood return state is a condition in which proper blood return becomes impossible due to the puncture needle 22 connecting patient H to the venous blood circuit L2 falling out of patient H's blood vessel, blood coagulating in the venous blood circuit L2 and blocking or narrowing the flow path, or the venous blood circuit L2 or gas circuit L3 bending. A clogged blood purifier 5 state is a condition in which the blood purification membrane inside the blood purifier 5 becomes clogged due to blood coagulation, making proper blood purification impossible. A faulty circuit connection state is a condition in which the arterial blood circuit L1, venous blood circuit L2, or gas circuit L3 is not properly connected to other components, and air is leaking to the outside. This condition includes, for example, a state in which the connection between the arterial blood circuit L1 and the blood inlet 5a of the blood purifier 5, or the connection between the gas circuit L3 and the pressure measuring unit S1, is made by fitting, and the strength of the fitting is insufficient. A malfunction in pump P1 refers to a state where the operation of pump P1 is significantly inferior to the operation that is originally intended. This state includes, for example, a situation where, despite being supplied with a predetermined amount of power, the rotational speed of pump P1 is significantly lower than the preset rotational speed.

[0062] The calculation unit 61 generates malfunction information if it determines that the blood withdrawal or blood return process of the blood purification device 1 is in a malfunction state. Malfunction information is information generated based on the malfunction state and indicates that the blood withdrawal or blood return process is not being performed normally. Malfunction information may also include information such as the location where the malfunction is occurring, the time when the malfunction occurred, and the measures that can be taken in response to the malfunction. Furthermore, the malfunction information may also include any of the specific details of the malfunction (malfunctioning blood withdrawal, malfunctioning blood return, blockage of the blood purifier 5, faulty circuit connection, malfunction of pump P1, and other malfunctions).

[0063] Then, based on the malfunction information, the calculation unit 61 modifies the pump drive information to stop the drive of pump P1, and modifies the clamp drive information to occlude arterial clamp V1 and venous clamp V2. After that, the calculation unit 61 transmits the modified pump drive information to the pump control unit 62 and the modified clamp drive information to the clamp control unit 63.

[0064] In this case, the calculation unit 61 displays the malfunction information via the display 4 and notifies the administrator of the blood purification device 1 that the blood withdrawal or blood return process is not being performed normally. By checking the displayed malfunction information, the administrator can grasp the fact and nature of the malfunction and take measures such as replacing components or moving patient H. In particular, by including the specific details of the malfunction information (blood withdrawal failure, blood return failure, blockage of the blood purifier 5, faulty circuit connection, pump P1 malfunction, and other malfunctions), the calculation unit 61 can also individually notify the administrator of the malfunction determination result. That is, more specific malfunctions can be individually notified, making it easier for the administrator to take action. In this embodiment, the malfunction information is displayed on the display 4 provided in the blood purification device 1, but this is not the only option. The malfunction information may also be displayed on the display of an external device. For example, the calculation unit 61 may transmit the malfunction information to a mobile terminal device such as a smartphone or tablet, and the malfunction information may be displayed on the mobile terminal device. The malfunction information may also be output by voice or warning sound. For example, a speaker may be installed on the blood purification device 1 or a speaker on a portable terminal device may be used to notify the system of malfunctions via the speaker. In particular, if a speaker is installed on the blood purification device 1, it becomes easier for patient H to become aware of the malfunction and take appropriate action, such as informing the administrator of the blood purification device 1. Furthermore, the malfunction information may be output to an external server device. Specifically, the calculation unit 61 may output the malfunction information to an external server device via the communication unit.

[0065] The pump control unit 62 generates a pump drive signal to control pump P1 to a desired state based on the received pump drive information. Here, the desired state includes the rotation direction of pump P1, the timing of switching the rotation direction, the amount of rotation, and stopping the rotation (drive). When the pump control unit 62 receives the corrected pump drive information, it generates a pump drive signal to stop the drive of pump P1. Then, the pump control unit 62 transmits the generated pump drive signal to pump P1.

[0066] The clamp control unit 63 generates an arterial clamp drive signal to control the arterial clamp V1 to a desired open / closed state, and a venous clamp drive signal to control the venous clamp V2 to a desired open / closed state, based on the received clamp drive information. Here, the desired open / closed state includes the opening and closing of the clamps and the timing of their switching. When the clamp control unit 63 receives the modified clamp drive information, it generates clamp drive signals to occlude the arterial clamp V1 and the venous clamp V2. Subsequently, the clamp control unit 63 transmits the generated arterial clamp drive signal to the arterial clamp V1 and the generated venous clamp drive signal to the venous clamp V2.

[0067] (Processing in blood purification devices) Next, the process related to the treatment of patient H by the blood purification device 1 according to this embodiment will be described with reference to Figures 5 to 9. Here, Figure 5 is a flowchart showing the flow of treatment in the blood purification device 1 according to this embodiment. Figure 6 is a diagram of the configuration of the extracorporeal circulation unit 8 during blood withdrawal in the blood purification device 1 according to this embodiment. Figure 7 is a diagram of the configuration of the extracorporeal circulation unit 8 during blood return in the blood purification device 1 according to this embodiment. Figure 8 is a flowchart showing the flow of treatment termination in the blood purification device according to the first embodiment. Figure 9 is a diagram of the configuration of the extracorporeal circulation unit 8 when treatment is terminated in the blood purification device 1 according to this embodiment.

[0068] First, as shown in Figure 5, the processing unit 6 determines whether or not patient information has been received (S11). Specifically, when the administrator of the blood purification device 1 operates the input unit 4a and inputs information related to patient H, the patient information is transmitted from the input unit 4a to the calculation unit 61 of the processing unit 6. If the processing unit 6 is equipped with a communication unit, the processing unit 6 may also receive patient information from an external device via the communication unit. If patient information is not received (S11: No), the settings related to treatment cannot be made, and the process does not proceed to the next step in this flow.

[0069] Next, when patient information is received in the processing unit 6 (S11: Yes), the processing unit 6 executes preparatory processing for blood purification treatment (S12). Specifically, the processor 6a of the processing unit 6 reads the preparatory processing program stored in memory 6b, determines the treatment settings corresponding to patient H from the patient information, and sequentially executes priming, gas purging, and initial blood draining processes.

[0070] Next, the processing unit 6 reads out blood flow information and pressure value information corresponding to the received patient information (S13). Specifically, the calculation unit 61 of the processing unit 6 refers to the blood flow table and pressure value table stored in the storage unit 64 and reads out the blood flow information and pressure value information corresponding to the received patient information.

[0071] Next, the processing unit 6 generates initial pump drive information and initial clamp drive information (S14). Specifically, the calculation unit 61 of the processing unit 6 determines the amount of air introduced and discharged per cycle of the pump P1 in the alternating control of blood withdrawal and blood return processes, corresponding to the read blood flow rate information, and generates pump drive information corresponding to this determination. The calculation unit 61 of the processing unit 6 also determines the timing of opening and closing of the arterial clamp V1 and venous clamp V2 corresponding to the drive of the pump P1, and generates clamp drive information corresponding to this determination.

[0072] Next, in the processing unit 6, the generated pump drive information and clamp drive information are stored in the storage unit 64 as setting information (S15). This stores the control information for the devices used in the treatment of patient H that is about to begin.

[0073] Next, the pump drive information generated by the calculation unit 61 of the processing unit 6 is transmitted to the pump control unit 62, and the clamp drive information is transmitted to the clamp control unit 63. Subsequently, the pump control unit 62 generates a pump drive signal to control pump P1 to a desired state based on the received pump drive information. In other words, the pump control unit 62 generates a pump drive signal to actually transmit to pump P1 based on the received pump drive information. Meanwhile, the clamp control unit 63 generates an arterial clamp drive signal to control arterial clamp V1 to a desired open / closed state, and also generates a venous clamp drive signal to control venous clamp V2 to a desired open / closed state based on the received clamp drive information. In other words, the clamp control unit 63 generates clamp drive signals to actually transmit to arterial clamp V1 and venous clamp V2 based on the received clamp drive information. After that, the generated pump drive signal is transmitted to pump P1, the arterial clamp drive signal is transmitted to arterial clamp V1, and the venous clamp drive signal is transmitted to venous clamp V2, completing the setting of the treatment process for patient H (S16).

[0074] Next, the pump P1, arterial clamp V1, and venous clamp V2 perform predetermined actions at predetermined timings to execute the blood purification process (S17). Specifically, as can be seen in Figure 6, when the pump P1 rotates in reverse, the arterial clamp V1 opens the flow path and the venous clamp V2 closes the flow path. As a result, air is discharged from the branch 23, blood is collected from patient H, and the collected blood is stored in the branch 23 via the blood purifier 5 (blood withdrawal process). Subsequently, as can be seen in Figure 7, when the pump P1 rotates in the forward direction, the arterial clamp V1 closes the flow path and the venous clamp V2 opens the flow path. As a result, air is introduced towards the branch 23, and the blood stored in the branch 23 is returned to patient H (blood return process).

[0075] In this type of blood withdrawal and return process, the blood flow rate during processing can be adjusted simply by changing the air discharge and suction volume of pump P1. In other words, by simply controlling the rotation speed of pump P1, it is possible to easily handle blood flow rates of 15 ml / min or less, 3 ml / min or less, and also easily handle blood flow rates in the range of 100 ml / min or more and 600 ml / min or less.

[0076] Next, the calculation unit 61 of the processing unit 6 determines whether or not treatment for patient H has been completed (S18). If treatment for patient H has not been completed (S18: No), the process returns to the blood purification process in S17. That is, the blood purification process, which consists of blood withdrawal and blood return, is repeated until treatment is completed, and treatment for patient H progresses. After a predetermined cycle or time has elapsed, it is determined that treatment is complete (S18: Yes), and this flow ends.

[0077] In the blood purification process shown in S17 of Figure 5, the processing flow related to stopping the pump drive and closing each clamp, as shown in Figure 8, is also repeatedly executed in parallel. Specifically, this processing flow is executed each time a pressure signal is received from the pressure measuring unit S1 and each time a detection signal is received from the liquid level detection unit 24. In this processing flow, first, the processing unit 6 determines whether the measured value (pressure value) from the pressure measuring unit S1 is within a predetermined range (S21). Specifically, the calculation unit 61 of the processing unit 6 calculates the measured value based on the pressure signal received from the pressure measuring unit S1, compares the measured value with the pressure value information read in S13, and determines whether the measured value is within a predetermined range.

[0078] Here, the predetermined range (pressure value information) may be set appropriately for each patient H, treatment content, and configuration of the treatment device. If patient H is an adult with a relatively large blood flow (i.e., a large body weight), for example, the measured value during blood withdrawal may be a minimum of -200 mmHg, and the measured value during blood return may be within the range of a minimum of 10 mmHg and a maximum of 250 mmHg. Also, if patient H is a newborn or child with a very small body weight compared to an adult, for example, the measured value during blood withdrawal may be a minimum of -100 mmHg, and the measured value during blood return may be a minimum of 10 mmHg and a maximum of 50 mmHg.

[0079] In S21, if it is determined that the measurement value of the pressure measuring unit S1 is outside the predetermined range (S21: No), the next step S22 is skipped and the process proceeds to S23. On the other hand, if it is determined that the measurement value of the pressure measuring unit S1 is within the predetermined range (S21: Yes), the processing unit 6 determines whether the movement time of the blood liquid level in the liquid level detection unit 24 is within the predetermined range (S22). Here, the movement time is calculated by the calculation unit 61 based on the detection signal related to blood liquid level detection in the branching unit 23, and takes time for the blood liquid level to move from one sensor to the other sensor provided in the branching unit 23. Specifically, the calculation unit 61 determines, based on the received detection signal, whether or not blood is present at the position of the sensor consisting of the oscillating element 24a and the receiving element 24c, and whether or not blood is present at the position of the sensor consisting of the oscillating element 24b and the receiving element 24d. Furthermore, the calculation unit 61 determines that the blood surface has passed when the determination of whether or not blood is present changes at each sensor, and calculates the time difference at the time when the determination changes at each sensor as the travel time.

[0080] The calculation unit 61 compares the actual travel time calculated in this way with the theoretical travel time calculated based on the pump drive information read from the storage unit 64, and determines whether there is a significant discrepancy in the actual travel time (i.e., whether the actual travel time is within a predetermined range). For example, if the theoretical time is set to 100%, and the actual travel time is 200% or more (i.e., more than twice as much), the calculation unit 61 will determine that there is a significant discrepancy and that the actual travel time is outside the predetermined range. The calculation unit 61 may determine that there is no significant discrepancy if the difference is, for example, 5% or less, or it may determine that there is a significant discrepancy. The predetermined range can be set as appropriate depending on the patient, device, or treatment method.

[0081] Then, if the actual transfer time is determined to be within the specified range (S22: Yes), it is determined that the blood withdrawal or blood return process is being performed normally (not in a faulty state), and this flow terminates. Note that S21 and S22 do not have to be performed in this order; they may be performed in reverse order or simultaneously.

[0082] On the other hand, if the actual travel time is outside the predetermined range (S22: No), the calculation unit 61 of the processing unit 6 determines that the blood withdrawal process or blood return process is not being performed normally (it is in a faulty state) and generates faulty state information related to the faulty state (S23).

[0083] Examples of malfunctions include, as mentioned above, poor blood withdrawal, poor blood return, clogging of the blood purifier 5, faulty circuit connections, or a malfunction of pump P1. The method for identifying each condition and the corresponding values ​​can be set appropriately depending on the patient H, their treatment method, and the parts used, but an example is shown below.

[0084] If patient H is a relatively large adult, for example, if the measured value (pressure value) during blood withdrawal falls below -200 mmHg, it is judged to be a state of poor blood withdrawal, a clogged blood purifier 5, a faulty circuit connection, or a malfunction of pump P1. This is because, if the blood withdrawal process is performed properly, a sufficient amount of blood is stored in the branching section 23, creating pressure. However, in the above conditions, the blood withdrawal process is poor, and insufficient blood storage results in a decrease in pressure. Also, for example, if the measured value during blood return is outside the range of 10 mmHg to 250 mmHg, it is judged to be a state of poor blood return, a faulty circuit connection, or a malfunction of pump P1. If the blood return process is performed properly, a sufficient amount of blood is drawn out from the branching section 23, resulting in a nearly constant pressure. However, in the above conditions, the blood return process is poor, and insufficient blood is drawn out, causing the pressure to rise. Therefore, if it exceeds 250 mmHg, it is judged to be one of the above conditions. Furthermore, if the puncture needle 22 falls out of patient H's blood vessel, or if pump P1 can only operate in forward rotation mode, the pressure will drop significantly, and if it falls below 10 mmHg, it will be judged to be in the above condition.

[0085] Furthermore, for example, during the blood withdrawal process, if the theoretical movement time of the blood level in the liquid level detection unit 24 is set to 30 seconds, and the actual movement time exceeds 60 seconds, it is determined that there is a blood withdrawal failure, a blockage in the blood purifier 5, a faulty circuit connection, or a malfunction in the pump P1. This is because, if the blood withdrawal process is performed correctly, a sufficient amount of blood will be stored in the branching unit 23, causing the liquid level to move. However, in the above conditions, the blood withdrawal process is deemed to be inefficient, resulting in insufficient blood storage and a longer liquid level movement time. Similarly, for example, during the blood return process, if the theoretical movement time of the blood level is set to 30 seconds, and the actual movement time exceeds 60 seconds, it is determined that there is a blood return failure, a faulty circuit connection, or a malfunction in the pump P1. If the blood return process is performed correctly, a sufficient amount of blood will be discharged from the branching unit 23, causing the liquid level to move. However, in the above conditions, the blood return process is deemed to be inefficient, resulting in insufficient blood discharge and a longer liquid level movement time.

[0086] Furthermore, the term "defective condition" is not limited to the conditions described above, and the reason and nature of the defect may be unknown. In other words, a defective condition is sufficient if it indicates that the blood withdrawal or blood return process was not performed correctly.

[0087] Next, in the processing unit 6, the pump drive information and clamp drive information are modified based on the generated malfunction information (S24). Specifically, the calculation unit 61 of the processing unit 6 modifies the pump drive information to stop the drive of the pump P1, and modifies the clamp drive information to close each clamp.

[0088] Next, in the processing unit 6, the pump drive signal and clamp drive signal are regenerated based on the corrected pump drive information and clamp drive information, and the regenerated pump drive signal and clamp drive signal are retransmitted to the pump P1 and each clamp (S25). Specifically, the pump control unit 62 of the processing unit 6 receives the regenerated pump drive information from the calculation unit 61 and regenerates a pump drive signal to control the pump P1 to stop driving based on this pump drive information. In addition, the clamp control unit 63 of the processing unit 6 receives the regenerated clamp drive information from the calculation unit 61 and regenerates a clamp drive signal to control each clamp to close based on this clamp drive information.

[0089] The pump control unit 62 then transmits the regenerated pump drive signal to the pump P1, and the clamp control unit 63 transmits the regenerated clamp drive signal to each clamp. As a result, the pump P1 is stopped, each clamp is closed (S26, Figure 9), and the treatment process by the blood purification device 1 is stopped (S27). This makes it possible to switch the blood purification device 1 to a safe mode, thereby ensuring safety in blood purification treatment.

[0090] (Effects of the first embodiment) In this embodiment, of the three circuits provided, the pressure measuring unit S1 is provided only in the gas circuit L3, while the arterial blood circuit L1 and venous blood circuit L2, which are blood circuits, do not have a pressure measuring unit S1. As a result, the increase in extracorporeal circulating blood volume caused by the pressure measuring unit (pressure sensor) during blood withdrawal and blood return processing is suppressed. Furthermore, since the arterial blood circuit L1 and venous blood circuit L2 are provided only with a branching section 23 and a clamp, the increase in extracorporeal circulating blood volume caused by various pumps and valves is also suppressed. In other words, the amount of extracorporeal circulating blood volume is significantly reduced compared to conventional cases where multiple components are provided in the blood circuit. Therefore, it is possible to treat not only relatively heavy adult patients but also light patients such as newborns or children with low body weight at a low blood flow rate (e.g., 10 ml / min).

[0091] Furthermore, in this embodiment, since blood withdrawal and blood return are performed alternately, the amount of blood processed at one time is halved compared to when blood withdrawal and blood return are performed simultaneously. For typical adult patients, simultaneous processing is increasingly necessary to shorten treatment time. On the other hand, for neonatal or pediatric patients with a small blood volume, the amount of blood to be treated is small, so even if the amount of blood processed at one time is halved, no problems arise, and the burden of treatment does not increase.

[0092] (Modified version of the first embodiment) In the above embodiment, in order to minimize the extracorporeal blood volume, only clamps and branching sections 23 were provided in the arterial blood circuit L1 and the venous blood circuit L2. However, from the viewpoint of further ensuring the safety of patient H during treatment and from the viewpoint of minimizing the extracorporeal blood volume, bubble sensors and temperature sensors may also be provided. For example, a bubble sensor may be provided near the arterial clamp V1.

[0093] Furthermore, in the above embodiment, the arterial blood circuit L1 and the venous blood circuit L2 were connected by a Y-shaped tube 21, and a single puncture needle 22 was inserted into the patient H. However, the system is not limited to this as long as blood withdrawal and blood return processes can be repeated alternately. For example, as shown in Figure 10, a double-needle configuration in which a puncture needle is connected to each blood circuit is also possible. That is, the arterial blood circuit L1 is connected to the arterial (blood withdrawal) puncture needle 81 via a connector 71, and the venous (blood return) puncture needle 82 is connected to the venous blood circuit L2 via a connector 72.

[0094] In the case of such a double needle, since the branching point 23 is located downstream of the blood purifier 5, if the pressure measured during blood withdrawal control is below the lower limit, the status of the puncture needle 81 on the blood withdrawal side, the arterial blood circuit L1 which is the blood withdrawal blood line, and the blood purifier 5 are checked, and work is performed to restore the malfunction to a normal state. Similarly, if the pressure measured during blood return control is above the upper limit, the puncture needle 82 on the blood return side and the venous blood circuit L2 which is the blood return blood line are checked, and work is performed to restore the malfunction to a normal state. In other words, even if a value exceeding the pressure value is detected, it is not necessary to check the entire extracorporeal circulation unit 8, and the cause of the malfunction is narrowed down, enabling early and accurate response.

[0095] Furthermore, in the above embodiment, the calculation unit 61 of the processing unit 6 controlled the opening and closing of each clamp based on the blood flow rate from the pump P1 (i.e., the blood flow rate per stroke), but the control may also be performed based on the operating time of the pump P1. In other words, the control of opening and closing each clamp may be time-based control instead of blood flow rate control.

[0096] <Second Embodiment> In the first embodiment, the branching section 23 was provided in the venous blood circuit L2, but it may be provided in the arterial blood circuit L1 instead. Also, in the first embodiment, the pressure measuring section S1 was provided in the gas circuit L3, but it may be provided in the branching section 23 instead. A blood purification device having such a configuration will be described as the second embodiment with reference to Figure 11. Here, Figure 11 is a diagram of the configuration of the extracorporeal circulation section of the blood purification device according to this embodiment. Note that the parts that differ from the first embodiment will be described in principle, and the same parts will be omitted from the description, and the same reference numerals will be used in the drawings in principle.

[0097] Next, as shown in Figure 11, the extracorporeal circulation unit 108 has three circuits: an arterial blood circuit L101, a venous blood circuit L102, and a gas circuit L3, as well as a branching section 123 connecting the venous blood circuit L102 and the gas circuit L3. Compared to the extracorporeal circulation unit 8 according to the first embodiment, the extracorporeal circulation unit 108 has the same basic components, differing only in their arrangement and the length of each blood circuit.

[0098] As can be seen in Figure 11, one end of the arterial blood circuit L101 is connected to a single puncture needle 22 inserted into the patient H's arm via a Y-shaped tube 21, and the other end is connected to the blood inlet 5a of the blood purifier 5. An arterial clamp V1 is also provided near the aforementioned end of the arterial blood circuit L101. Furthermore, a branch section 123 is provided in the arterial blood circuit L101.

[0099] In this embodiment, the branch section 123 is located between the blood purifier 5 and the arterial clamp V1. The arterial blood circuit L101 extending from the arterial clamp V1 is connected to the side of the branch section 123, and the arterial blood circuit L101 extending to the blood inlet 5a of the blood purifier 5 is connected to the bottom of the branch section, which is located vertically downwards. Furthermore, one end of the gas circuit L3 is connected to the top of the branch section 123, which is located vertically upwards, and a pressure measuring unit S101 is connected to the branch section 123, branching off from the gas circuit L3. Around the branch section 123, similar to the branch section 23 in the first embodiment, a liquid level detection unit 24 is provided for detecting the liquid level of the blood stored in the branch section 123.

[0100] Due to the structure of the branch section 123, blood withdrawn from patient H can be introduced from the side of the branch section 123, and the introduced blood is temporarily stored in the branch section 123. The stored blood can then be led out from the bottom of the branch section 123 to the blood purifier 5 via the arterial blood circuit L101.

[0101] As can be seen in Figure 11, one end of the venous blood circuit L102 is connected to a single puncture needle 22 inserted into the patient H's arm via a Y-shaped tube 21, and the other end is connected to the blood outlet 5b of the blood purifier 5. A venous clamp V2 is also provided on the venous blood circuit L102. One end of the gas circuit L3 is connected to the top of the branch 123, and the other end is open to the atmosphere. In addition, a pump P1 is provided on the gas circuit L3. Furthermore, a pressure measuring unit S101 is connected to the top of the branch 123 and measures the pressure at the branch 123 in conjunction with the blood withdrawal and blood return processes.

[0102] In this embodiment, when blood withdrawal is performed, the pump P1 rotates in reverse while the arterial clamp V1 opens the flow path and the venous clamp V2 closes the flow path. As a result, air is drawn from the branch 123 into the gas circuit L3, and the blood withdrawn from patient H is introduced into the interior of the branch 123 from the side of the branch 123 via the arterial blood circuit L101 and stored therein. On the other hand, when blood return is performed, the pump P1 rotates in forward direction while the arterial clamp V1 closes the flow path and the venous clamp V2 opens the flow path. As a result, air is drawn from the gas circuit L3 towards the branch 123 into the gas circuit L3, and the blood stored in the branch 123 is drawn out from the bottom of the branch 123 and introduced into the blood purifier 5 via the arterial blood circuit L101. The blood purified by the blood purifier 5 is then returned to patient H via the venous blood circuit L102. By repeating the above processes alternately, patient H is treated.

[0103] (Effects of the second embodiment) Thus, in this embodiment, a pressure measuring unit S101 is provided only at the branching section 123, and no pressure measuring units are provided in the arterial blood circuit L1 and the venous blood circuit L2, which are blood circuits. As a result, the installation of devices and components that would increase the extracorporeal circulation volume on the blood circuit is reduced. Therefore, as in the first embodiment, the extracorporeal circulation volume is significantly reduced compared to the conventional case where multiple pressure measuring units are provided in the blood circuit.

[0104] Furthermore, similar to the first embodiment, by controlling the pump P1, arterial clamp V1, and venous clamp V2, blood withdrawal and blood return processes can be performed alternately, thus avoiding a treatment burden on neonates or pediatric patients with small amounts of blood in their bodies.

[0105] (Modified version of the second embodiment) In the above embodiment, the branching section 123 was provided in the arterial blood circuit L101, and the venous blood circuit L102 was not provided with a branching section. However, as in the first embodiment, the branching section 123 may also be provided in the venous blood circuit L102. That is, the branching section 123 may be provided in both the arterial blood circuit L101 and the venous blood circuit L102, and the gas circuit L3, pump P1, and pressure measuring unit S101 may be provided in each branching section. The pressure measuring unit S101 may also be directly provided in each branching section. Even in these cases, a configuration without a pressure measuring unit in the blood circuit is adopted. Therefore, the installation of devices and components that lead to an increase in the extracorporeal circulation blood volume on the blood circuit is reduced, and the extracorporeal circulation blood volume can be reduced. Of course, the pressure measuring unit S101 may be provided in the gas circuit L3. Alternatively, the branching section 123 may be provided in the venous blood circuit L102, and the pressure measuring unit S101 may be provided in the said branching section 123.

[0106] In the above embodiment, the arterial blood circuit L101 and the venous blood circuit L102 were connected by a Y-shaped tube 21, and a single puncture needle 22 was inserted into the patient H. However, as with the modified example of the first embodiment, a double-needle configuration may also be used. In such a double-needle configuration, since the branching section 123 is located upstream of the blood purifier 5, if the pressure measured during blood withdrawal control is below the lower limit, the puncture needle on the blood withdrawal side and the arterial blood circuit L101, which is the blood withdrawal blood line, are checked, and work is performed to restore the malfunction to a normal state. Similarly, if the pressure measured during blood return control is above the upper limit, the puncture needle on the blood return side, the venous blood circuit L102, which is the blood return blood line, and the blood purifier 5 are checked, and work is performed to restore the malfunction to a normal state. In other words, even if an abnormal pressure value is detected, it is not necessary to check the entire extracorporeal circulation unit 108, and the cause of the malfunction is narrowed down, enabling early and accurate response.

[0107] <Embodiments of this disclosure> A first embodiment of the present disclosure is a blood purification device comprising: a blood purifier for purifying a patient's blood; an arterial blood circuit which serves as a blood flow path for introducing the blood withdrawn from the patient into the blood purifier; a venous blood circuit which serves as a blood flow path from the blood purifier to the patient; and a gas circuit connected to a branching point that branches either the arterial blood circuit or the venous blood circuit, which serves as a flow path for air, wherein the device comprises an arterial clamp capable of opening and closing the blood flow path of the arterial blood circuit to which the arterial blood circuit is attached, and the venous blood circuit A blood purification device comprising: a venous clamp capable of opening and closing the blood flow path of the venous blood circuit to which a device can be attached; a pump capable of introducing or releasing air into the gas circuit; a processing unit that controls the pump, the arterial clamp, and the venous clamp and alternately performs a blood withdrawal process by introducing the gas into the branching point and a blood return process by releasing the gas from the branching point; and a pressure measuring unit provided only in the gas circuit among the arterial blood circuit, the venous blood circuit, and the gas circuit, or provided only in the branching point.

[0108] Thus, because there is no pressure measuring unit in the blood circuit that would cause an increase in extracorporeal blood volume during blood withdrawal and blood return processes, the increase in extracorporeal blood volume caused by the pressure measuring unit is suppressed.

[0109] A second embodiment of the present disclosure is that, in the first embodiment, the processing unit comprises a calculation unit that generates pump drive information for controlling the pump and clamp drive information for controlling the arterial clamp and the venous clamp based on input patient information. This makes it possible to accurately control the blood flow even when the blood flow is relatively small, and to perform treatment with less burden on the patient.

[0110] A third embodiment of this disclosure is, in the second embodiment, that the calculation unit determines that the blood withdrawal process or the blood return process is in a faulty state when the measured value of the pressure measuring unit is outside a predetermined range, and generates faulty state information. This makes it possible to switch the blood purification device to a safe state, thereby ensuring safety in blood purification therapy.

[0111] A fourth embodiment of this disclosure is, in the second embodiment, that the calculation unit determines a faulty condition in the blood withdrawal process or the blood return process based on the time it takes for the blood level to move at a predetermined distance from the branching point, and generates faulty condition information. This makes it possible to switch the blood purification device to a safer state, thereby ensuring safety in blood purification therapy.

[0112] A fifth embodiment of this disclosure is that, in the third or fourth embodiment, the content of the malfunction includes at least one of a blood withdrawal failure, a blood return failure, a clogged blood purifier, a faulty circuit connection, and a pump failure. This makes it possible to switch the blood purifier to a safe state, thereby ensuring safety in blood purification therapy.

[0113] A sixth embodiment of this disclosure is, in the fifth embodiment, that the calculation unit individually determines the content of the malfunction and individually notifies the determination result. This makes it easier to understand the details of the malfunction of the blood purification device and to take appropriate action against the malfunction.

[0114] A seventh embodiment of this disclosure is, in the third or fourth embodiment, that the processing unit, based on the malfunction information, stops the pump from running and closes the arterial clamp and the venous clamp. This makes it possible to switch the blood purification device to a safe state and ensure safety in blood purification therapy.

[0115] An eighth embodiment of this disclosure is that, in the third or fourth embodiment, the processing unit outputs the faulty state information. This allows the administrator to confirm the faulty state information and take subsequent measures promptly.

[0116] A ninth embodiment of the present disclosure is, in a third embodiment, that the calculation unit determines the predetermined range based at least on the patient's weight. This enables safe treatment that corresponds to the patient's weight.

[0117] A tenth embodiment of the present disclosure is, in the fourth embodiment, that the calculation unit determines the travel time based at least on the patient's weight. This enables safe treatment that is appropriate to the patient's weight.

[0118] An eleventh embodiment of this disclosure, in the fourth embodiment, is that the branching section is provided with two liquid level detectors, and the calculation unit calculates the movement time based on the detection signals of the liquid level detectors. This makes it possible to determine a faulty condition and ensure safety in blood purification therapy.

[0119] A twelfth embodiment of the present disclosure is a blood purification circuit connected to a blood purifier for purifying a patient's blood, comprising: an arterial blood circuit which serves as a blood flow path for introducing the blood withdrawn from the patient into the blood purifier; a venous blood circuit which serves as a blood flow path from the blood purifier to the patient; a gas circuit which serves as a flow path for air and is connected to a branching section that branches off either the arterial blood circuit or the venous blood circuit; and a pressure measuring section which is provided only in the gas circuit among the arterial blood circuit, the venous blood circuit, and the gas circuit, or which is provided only in the branching section.

[0120] Thus, because there is no pressure measuring unit in the blood circuit that would cause an increase in extracorporeal blood volume during blood withdrawal and blood return processes, the increase in extracorporeal blood volume caused by the pressure measuring unit is suppressed. [Explanation of symbols]

[0121] 1. Blood purification device 2 Base Units 3 Main unit 4 displays 5. Blood Purifier 6 Processing Unit 7 Internal piping section 8 Extracorporeal Circulation Department 23 Branching point 24 Liquid level detection unit 61 Arithmetic section 62 Pump Control Unit 63 Clamp Control Unit 64 Storage section L1 arterial blood circuit L2 venous blood circuit L3 Gas Circuit S1 Pressure measuring unit V1 Arterial Clamp V2 Vein Clamp P1 Pump H patient

Claims

1. A blood purification device comprising: a blood purifier for purifying a patient's blood; an arterial blood circuit which serves as a blood flow path for introducing the blood withdrawn from the patient into the blood purifier; a venous blood circuit which serves as a blood flow path from the blood purifier to the patient; and a gas circuit which serves as a flow path for air and is connected to a branching point that branches off either the arterial blood circuit or the venous blood circuit. An arterial clamp capable of opening and closing the blood flow path of the arterial blood circuit to which the arterial blood circuit is attached, A venous clamp capable of opening and closing the blood flow path of the venous blood circuit to which the venous blood circuit is attached, A pump capable of introducing or releasing air into the aforementioned gas circuit, A processing unit that controls the pump, the arterial clamp, and the venous clamp, and alternately performs a blood withdrawal process by introducing the gas into the branching section and a blood return process by releasing the gas from the branching section. A blood purification device comprising the arterial blood circuit, the venous blood circuit, and a pressure measuring unit provided only in the gas circuit or only in the branching portion of the gas circuit.

2. The blood purification apparatus according to claim 1, wherein the processing unit comprises a calculation unit that generates pump drive information for controlling the pump and clamp drive information for controlling the arterial clamp and the venous clamp based on input patient information.

3. The blood purification apparatus according to claim 2, wherein the calculation unit determines that the blood removal process or the blood return process is in a poor state when the measurement value of the pressure measuring unit is outside a predetermined range, and generates information indicating a poor state.

4. The blood purification apparatus according to claim 2, wherein the calculation unit determines a defective state in the blood removal process or the blood return process based on the time it takes for the blood level to move over a predetermined distance at the branching point, and generates defective state information.

5. The blood purification apparatus according to claim 3 or 4, wherein the contents of the aforementioned defective state include at least one of a blood withdrawal failure, a blood return failure, a clogged state of the blood purifier, a faulty circuit connection, and a malfunction of the pump.

6. The blood purification apparatus according to claim 5, wherein the calculation unit individually determines the content of the defective state and individually notifies the determination result.

7. The blood purification apparatus according to claim 3 or 4, wherein the processing unit performs the operation of stopping the pump and occluding the arterial clamp and the venous clamp based on the defective state information.

8. The blood purification apparatus according to claim 3 or 4, wherein the processing unit outputs the defective state information.

9. The blood purification apparatus according to claim 3, wherein the calculation unit determines the predetermined range based at least on the patient's weight.

10. The blood purification apparatus according to claim 4, wherein the calculation unit determines the travel time based at least on the patient's weight.

11. Two liquid level detectors are provided at the aforementioned branching section. The blood purification apparatus according to claim 4, wherein the calculation unit calculates the travel time based on the detection signal of the liquid level detector.

12. A blood purification circuit connected to a blood purifier that purifies a patient's blood, An arterial blood circuit which serves as a blood flow path for introducing the blood drawn from the patient into the blood purifier, A venous blood circuit that serves as a blood flow path from the blood purifier to the patient, A gas circuit is connected to a branching point that branches off either the arterial blood circuit or the venous blood circuit, and serves as an air passage. A blood purification circuit having the arterial blood circuit, the venous blood circuit, and a pressure measuring unit provided only in the gas circuit or only in the branching portion of the gas circuit.

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