Blood purification system and intermediate system

Abstract

When the blood purification system is connected to the ECMO system (100), the circulation of the blood purification system (200) is maintained during the recovery of the ECMO system (100) after the ECMO system (100) has failed. A blood purification system (200) connected to an ECMO system (100) having an ECMO blood pump (120) and an artificial lung (130) is provided with a water removal control unit (281) that maintains the concentration of blood flowing through the blood purification system (200) at a predetermined concentration when the rate of change in the flow rate of blood in the ECMO system (100) exceeds a predetermined threshold value.

Description

Technical Field

[0001] The present invention relates to a blood purification system connected to an extracorporeal membrane oxygenation (ECMO) system and an intermediate system provided at a connection site between the extracorporeal membrane oxygenation system and the blood purification system. Background Art

[0002] In the intensive care area, patients with weak heart and lung functions are treated using an extracorporeal membrane oxygenation (hereinafter also referred to as ECMO: extracorporeal membrane oxygenation). Among such patients, continuous renal replacement therapy (hereinafter also referred to as CRRT) for blood purification is sometimes required due to the complication of renal failure. A patient during the implementation of ECMO is administered an anticoagulant in the ECMO circuit and has a bleeding tendency. Here, if blood is sent and removed from other blood vessels for CRRT, it may be necessary to further administer an anticoagulant in the CRRT circuit, increasing the bleeding tendency, which is not preferable. In addition, at the central vein, in addition to blood sending and removing for ECMO, multiple catheters are often inserted for general management, making it difficult to newly insert a vascular access for CRRT. Therefore, an attempt has been made in the clinical field to directly connect the CRRT circuit to the ECMO circuit (see Patent Document 1).

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2010-528781 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] When the CRRT system is connected to the ECMO system and the ECMO system has a problem and the circulation becomes unstable, the CRRT system is affected by the ECMO system and the circulation stops. Therefore, thrombi are likely to be generated in the CRRT circuit. When the CRRT system is restarted after the ECMO system is restored, the thrombi generated in the CRRT circuit may be transported to the ECMO circuit, and in addition, the CRRT circuit may become unable to circulate due to the thrombi.

[0008] Therefore, an object of the present invention is to provide a blood purification system and an intermediate system that can maintain the circulation of the blood purification system during the restoration process of the ECMO system after the ECMO system has a problem when the blood purification system is connected to the ECMO system.

[0009] Solutions for Solving the Problems

[0010] The present invention relates to a blood purification system, which is a blood purification system connected to an extracorporeal membrane lung system. The extracorporeal membrane lung system has an ECMO blood pump and an artificial lung disposed downstream of the ECMO blood pump. The blood purification system includes: a blood extraction line, the upstream end of which is connected to the extracorporeal membrane lung system; a blood purifier, which is connected to the downstream end of the blood extraction line; a blood return line, the upstream end of which is connected to the blood purifier and the downstream end of which is connected to the extracorporeal membrane lung system; a flow meter, which measures the flow rate of the extracorporeal membrane lung system; and a control unit. The control unit includes: a water removal control unit, which maintains the concentration of the liquid flowing through the blood purification system at a specified concentration when the change rate of the flow rate measured by the flow meter exceeds a specified threshold value.

[0011] In addition, preferably, the blood purification system further includes: a flow rate adjustment unit, which is provided in the blood extraction line to adjust the flow rate of the blood extraction line; and a pressure gauge, which measures the pressure at the connection part between the extracorporeal membrane lung system and the blood extraction line or the blood return line. The control unit further includes: a circulation control unit, which reduces the flow rate of the flow rate adjustment unit to a specified flow rate when the change rate of the flow rate measured by the flow meter exceeds a specified threshold value and the pressure measured by the pressure gauge is within a specified range.

[0012] In addition, preferably, the blood purification system further includes: a bypass line, which connects the upstream side of the blood purification pump in the blood extraction line to the blood return line; a first flow path switching unit, which is disposed near the connection part between the blood extraction line and the bypass line; and a second flow path switching unit, which is disposed near the connection part between the blood return line and the bypass line. The control unit includes: a switching control unit, which switches the second flow path switching unit to switch the flow path of the liquid flowing through the blood return line to the bypass line, switches the first flow path switching unit to stop the inflow of the liquid from the extracorporeal membrane lung system to the blood extraction line, and allows the liquid flowing through the bypass line to flow into the blood extraction line when the change rate of the flow rate measured by the flow meter exceeds a specified threshold value and the pressure measured by the pressure gauge exceeds a specified range.

[0013] In addition, preferably, the blood purification system further includes a blood return pump provided in the blood return line. The upstream end of the blood extraction line is connected to the downstream side of the ECMO blood pump in the extracorporeal membrane lung system, and the downstream end of the blood return line is connected to the downstream side of the ECMO blood pump in the extracorporeal membrane lung system.

[0014] In addition, preferably, the blood purification system further includes: a pressure buffer unit provided upstream of the blood return pump in the blood return line and capable of storing a predetermined amount of liquid; and a buffer unit pressure gauge for measuring the pressure of the pressure buffer unit. The control unit further includes: a flow rate control unit that adjusts the flow rates of the flow rate adjustment unit and the blood return pump so that the measured value of the buffer unit pressure gauge falls within a predetermined range.

[0015] In addition, preferably, the present invention relates to an intermediate system provided at the connection portion between an extracorporeal membrane oxygenation (ECMO) system and a blood purification system. The extracorporeal membrane oxygenation system has an ECMO blood pump and an artificial lung disposed downstream of the ECMO blood pump. The blood purification system has a blood purification pump, a blood purifier disposed downstream of the blood purification pump, a drainage line for discharging filtrate from the blood purifier, and a drainage pump provided in the drainage line. The intermediate system includes: an intermediate blood extraction line having an upstream end connected to a position downstream of the ECMO blood pump in the extracorporeal membrane oxygenation system and a downstream end connected to the upstream end of the blood purification system; a flow rate adjustment unit provided in the intermediate blood extraction line for adjusting the flow rate of the intermediate blood extraction line; an intermediate blood return line having an upstream end connected to the downstream end of the blood purification system and a downstream end connected to a position downstream of the ECMO blood pump in the extracorporeal membrane oxygenation system; a blood return pump provided in the intermediate blood return line; a flow meter for measuring the flow rate of the extracorporeal membrane oxygenation system; a notification unit; and a control unit. The control unit determines that a problem has occurred in the extracorporeal membrane oxygenation system when the change rate of the flow rate measured by the flow meter exceeds a predetermined threshold, and causes the notification unit to notify the occurrence of the problem.

[0016] In addition, preferably, the intermediate system further includes: a bypass line connecting the downstream side of the flow rate adjustment unit in the intermediate blood extraction line to the intermediate blood return line; a first flow path switching unit disposed near the connection portion between the intermediate blood extraction line and the bypass line; a second flow path switching unit disposed near the connection portion between the intermediate blood return line and the bypass line; and a pressure gauge for measuring the pressure at the connection portion between the extracorporeal membrane oxygenation system and the intermediate blood extraction line or the intermediate blood return line. The control unit includes: a switching control unit that switches the second flow path switching unit to switch the flow path of the liquid flowing in the intermediate blood return line to the bypass line, switches the first flow path switching unit to stop the inflow of the liquid from the extracorporeal membrane oxygenation system to the intermediate blood extraction line, and causes the liquid flowing in the bypass line to flow into the intermediate blood extraction line when the change rate of the flow rate measured by the flow meter exceeds a predetermined threshold and the pressure measured by the pressure gauge exceeds a predetermined range.

[0017] Effects of the Invention

[0018] According to the present invention, a blood purification system and an intermediate system can be provided, which can maintain the circulation of the blood purification system through a circulation control unit and a water removal flow control unit when a problem occurs in an ECMO system connected to the blood purification system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 FIG. is a diagram showing a schematic configuration of an ECMO system and a CRRT system according to a first embodiment of the present invention.

[0020] Figure 2 FIG. is a block diagram of a CRRT system according to a first embodiment of the present invention.

[0021] Figure 3 FIG. is a diagram for explaining an operating state of the CRRT system when a minor problem occurs in the ECMO system according to the first embodiment of the present invention.

[0022] Figure 4 FIG. is a diagram for explaining an operating state of the CRRT system when a serious problem occurs in the ECMO system according to the first embodiment of the present invention.

[0023] Figure 5 FIG. is a diagram showing a schematic configuration of an ECMO system and a CRRT system according to a second embodiment of the present invention.

[0024] Figure 6 FIG. is a block diagram of a CRRT system according to a second embodiment of the present invention.

[0025] Figure 7 FIG. is a diagram for explaining an operating state of the CRRT system when a minor problem occurs in the ECMO system according to the second embodiment of the present invention.

[0026] Figure 8 FIG. is a diagram for explaining an operating state of the CRRT system when a serious problem occurs in the ECMO system according to the second embodiment of the present invention.

[0027] Figure 9 FIG. is a diagram showing a schematic configuration of an ECMO system, a CRRT system, and an intermediate system according to a third embodiment of the present invention.

[0028] Figure 10 FIG. is a block diagram of a CRRT system and an intermediate system according to a third embodiment of the present invention.

[0029] Figure 11This is a diagram illustrating the operating states of the CRRT system and the intermediate system when a minor problem occurs in the ECMO system according to the third embodiment of the present invention.

[0030] Figure 12 This is a diagram illustrating the operating states of the CRRT system and the intermediate system when a serious problem occurs in the ECMO system according to the third embodiment of the present invention. Detailed Embodiments

[0031] Hereinafter, preferred embodiments of the continuous renal replacement therapy system and the intermediate system, which are blood purification systems of the present invention, will be described with reference to the accompanying drawings.

[0032] The intermediate system of the present invention is provided at the connection part between an extracorporeal membrane oxygenation (ECMO) system and a continuous renal replacement therapy (CRRT) system. The ECMO system described in this specification is suitable for patients with weak heart and lung functions, and uses a pump to transport the blood taken out from the patient to an artificial lung, and returns the blood with added oxygen in the artificial lung to the patient to assist the heart function and lung function of the patient. The CRRT system is suitable for patients with acute renal dysfunction, sepsis, patients with fluid overload, etc., and removes waste products and water in the blood little by little over time so as not to cause a sharp change in blood concentration, circulation volume, and blood pressure. The types of CRRT include continuous hemodialysis (CHD), continuous hemofiltration (CHF), and continuous hemodiafiltration (CHDF), but in each of the embodiments described below, the case of using continuous hemodiafiltration (CHDF) will be described as an example.

[0033] In addition, in the present embodiment, the blood purification system of the present invention is applied to the CRRT system, but it is not limited thereto. For example, the blood purification system can also be applied to a direct hemoperfusion (DHP) system. Direct hemoperfusion is a treatment method that adsorbs and removes inflammatory substances through an adsorptive blood purification filter as a blood purifier. In addition, the blood purification system can also be applied to a plasma adsorption therapy system.

[0034] <First Embodiment>

[0035] Refer to Figures 1 to 4 to describe the first embodiment in detail. Figure 1 This is a diagram showing the schematic configuration of the ECMO system 100 and the CRRT system 200 according to the first embodiment of the present invention. Figure 2 A block diagram showing the CRRT system 200.

[0036] (ECMO System)

[0037] As Figure 1As shown, the ECMO system 100 includes an ECMO blood circuit 110, an ECMO blood pump 120, an artificial lung 130, and a control unit 140.

[0038] The ECMO blood circuit 110 is a circuit for extracorporeal circulation of a patient's blood, and is composed of a blood withdrawal line 110a, a connection line 110b, and a blood return line 110c. One end of the blood withdrawal line 110a is connected to a blood withdrawal cannula 111, and the other end is connected to the ECMO blood pump 120. The blood withdrawal line 110a has a first branch 110a1 and a second branch 110a2. Connectors such as three-way stopcocks are respectively installed at these first branch 110a1 and second branch 110a2.

[0039] One end of the connection line 110b is connected to the ECMO blood pump 120, and the other end is connected to the artificial lung 130.

[0040] In addition, in the present embodiment, a bypass line 113 that bypasses the first branch 110a1 and the second branch 110a2 is provided in the blood withdrawal line 110a. The connection part of the bypass line 113 and the blood withdrawal line 110a is connected by, for example, a Y-shaped connector (not shown). By providing the bypass line 113, in the case where the CRRT system 200 fails and stops operating, by switching the flow path from the blood withdrawal cannula 111 to the ECMO blood pump 120 to the bypass line 113, the ECMO system can operate more safely.

[0041] One end of the blood return line 110c is connected to the artificial lung 130, and the other end is connected to a blood delivery cannula 112. In order to monitor the operating condition of the ECMO system 100, a flowmeter 114 is installed in the blood return line 110c. In the present embodiment, an ultrasonic flowmeter is used as the flowmeter 114. As the flowmeter 114, an optical flowmeter or the like can also be used.

[0042] The ECMO blood pump 120 withdraws blood from the patient's vein via the blood withdrawal cannula 111 and the blood withdrawal line 110a. The withdrawn blood is transported to the artificial lung 130 through the connection line 110b, and then returned to the patient through the blood return line 110c via the blood delivery cannula 112. As the ECMO blood pump 120, a known centrifugal pump or roller pump is used.

[0043] The artificial lung 130 includes a hollow fiber membrane (not shown) formed by bundling a plurality of hollow fibers having many micropores. By allowing oxygen to flow inside the hollow fibers and blood to flow outside the hollow fibers, oxygen is added to the blood delivered from the ECMO blood pump 120, and carbon dioxide is removed. In addition, the artificial lung 130 captures air bubbles present in the delivered blood to prevent them from flowing downstream in the ECMO circuit. As the artificial lung 130, a known membrane-type artificial lung is used. In addition, the artificial lung 130 may have a heat exchange function.

[0044] The control unit 140 is composed of an information processing device (computer), and drives each pump included in the ECMO system 100 and controls the operation of the ECMO system 100 by executing a control program.

[0045] (CRRT system)

[0046] As Figure 1 and Figure 2 shown, the CRRT system 200 includes a CRRT blood circuit 210, a blood purification pump 220, a blood purifier 230, a dialysate supply line 240, a dialysate drainage line 250, a replenishing fluid line 260, a bypass line 270, and a control unit 280.

[0047] The CRRT blood circuit 210 is a circuit for circulating the withdrawn blood, and includes a blood withdrawal line 210a and a blood return line 210b.

[0048] One end (upstream end) of the blood withdrawal line 210a is connected to the first branch 110a1 of the ECMO system 100 provided in the blood withdrawal line 110a, and the other end (downstream end) is connected to the blood purifier 230. The upstream end of the blood withdrawal line 210a may be connected to any part of the ECMO blood circuit 110, but in this embodiment, as an example, it is assumed to be connected to the upstream side of the ECMO blood pump 120.

[0049] In the blood withdrawal line 210a, a blood purification pump 220 serving as a flow rate adjustment unit is provided. A pressure gauge P1 is assembled on the upstream side of the blood purification pump 220, and a pressure gauge P2 is assembled on the downstream side of the blood purification pump 220. Since the pressure gauge P1 reflects the pressure at the connection portion between the blood withdrawal line 210a and the ECMO blood circuit 110, it can be used to monitor the internal pressure of the ECMO blood circuit 110. In addition, in order to monitor whether the flow rate delivered to the blood purifier 230 is normal, a flow meter 211 is assembled in the blood withdrawal line 210a. In the present embodiment, an ultrasonic flow meter is used as the flow meter 211. As the flow meter 211, an optical flow meter or the like can also be used. In addition, in the blood withdrawal line 210a, a clamp 212 for blocking the inflow of blood from the ECMO blood circuit is assembled between the blood purification pump 220 and the pressure gauge P1.

[0050] One end (upstream end) of the blood return line 210b is connected to the blood purifier 230, and the other end (downstream end) is connected to the second branch 110a2 of the ECMO system 100 provided in the blood withdrawal line 110a. Here, in order for the CRRT system 200 to operate in a manner not affected by high positive pressure, the blood return line 210b needs to be connected to the upstream side of the ECMO blood pump 120 which is a negative pressure portion in the ECMO blood circuit 110.

[0051] In the blood return line 210b, a drip chamber 213, a liquid exhaustion sensor 214, and a clamp 215 are assembled in order from the upstream side, and a pressure gauge P3 is assembled in the drip chamber 213. In order to remove bubbles, coagulated blood, etc. mixed into the blood, the drip chamber 213 stores a certain amount of blood. The pressure gauge P3 measures the internal pressure of the blood return line 210b. Since the pressure gauge P3 reflects the pressure at the connection portion between the blood return line 210b and the ECMO blood circuit 110, it can be used to monitor the internal pressure of the ECMO blood circuit 110.

[0052] In addition, in the present embodiment, the case where the pressure gauge P3 is assembled in the drip chamber 213 is shown as an example, but it is not limited thereto. For example, the pressure gauge P3 can also be assembled on the downstream side of the drip chamber 213 in the blood return line 210b to measure the internal pressure.

[0053] The blood purification pump 220 withdraws blood from the ECMO system 100 and adjusts the flow rate of the blood flowing in the blood withdrawal line 210a. The withdrawn blood is delivered to the blood purifier 230 through the blood withdrawal line 210a and then returned to the ECMO system 100 through the blood return line 210b.

[0054] The blood purifier 230 includes a dialysis membrane (not shown) housed inside a cylindrically shaped container body. The interior of the container body is divided by the dialysis membrane into a blood side flow path and a dialysate side flow path (both not shown), and water and waste move from the blood side flow path to the dialysate side flow path through the dialysis membrane, thereby purifying the blood.

[0055] The dialysate supply line 240 includes a dialysate pump 241 and is a line for supplying dialysate to the blood purifier 230, connecting the dialysate supply source D to the dialysate side flow path of the blood purifier 230. As the dialysate pump 241, a known roller pump or finger pump is used.

[0056] The dialysate drainage line 250 includes a drainage pump 251 and drains the dialysate from the blood purifier 230. The dialysate drainage line 250 connects the dialysate side flow path of the blood purifier 230 to the drainage storage unit F. As the drainage pump 251, a known roller pump or finger pump is used. In addition, a pressure gauge P4 is installed in the dialysate drainage line 250.

[0057] The supplementary fluid line 260 includes a supplementary fluid pump 261 and supplies the supplementary fluid supplied from the supplementary fluid supply source R to the blood return line 210b via the drip chamber 213 provided in the blood return line 210b. As the supplementary fluid, dialysate or physiological saline is used. In addition, the supplementary fluid can also be supplied between the blood purification pump 220 and the blood purifier 230 in the blood extraction line 210a.

[0058] The bypass line 270 is a line connecting the blood extraction line 210a and the blood return line 210b and is used to disconnect the CRRT system 200 from the ECMO system 100. The bypass line 270 is connected to the upstream side of the blood purification pump 220 in the blood extraction line 210a and to the downstream side of the blood return line 210b. The bypass line 270 has a bypass clamp 270a near the connection portion with the blood extraction line 210a and a bypass clamp 270b near the connection portion with the blood return line 210b. The bypass clamp 270a and the clamp 212 provided in the blood extraction line 210a together constitute the first flow path switching unit 271. In addition, the bypass clamp 270b and the clamp 215 provided in the blood return line 210b together constitute the second flow path switching unit 272.

[0059] In addition, in the present embodiment, the first flow path switching unit 271 and the second flow path switching unit 272 are each constituted by two clamps, but they may also be constituted by a three-way stopcock or the like.

[0060] The control unit 280 is composed of an information processing device (computer). By executing a control program, it drives each pump included in the CRRT system 200, and controls continuous hemodiafiltration (CHDF) for the blood flow rate, dialysate volume, and drainage volume with respect to the blood purifier 230. Additionally, the control unit 280 may also monitor the flow rates of the dialysate pump 241 disposed in the dialysate supply line 240, the drainage pump 251 disposed in the dialysate drainage line 250, and the replacement fluid pump 261 disposed in the replacement fluid line 260, and control the driving of each pump based on the flow rates measured by a metering unit (not shown) that measures the fluids (dialysate and replacement fluid) flowing in the CRRT system 200.

[0061] Furthermore, when the liquid exhaustion sensor 214 detects liquid exhaustion, the control unit 280 operates the clamp 215 to block the blood return line 210b, preventing air bubbles from mixing into the ECMO system 100.

[0062] Moreover, in order to monitor the operating status of the ECMO system 100, the control unit 280 acquires the measured value of the flowmeter 114, and monitors the internal pressure of the circuit of the ECMO system 100 based on the measured value of the pressure gauge P1 or the pressure gauge P3. The control unit 280 grasps the occurrence of problems such as the circulation of the ECMO system 100 becoming unstable based on the measured value of the flowmeter 114 and the measured value of the pressure gauge P1 or the pressure gauge P3. The control unit 280 is composed of a water removal control unit 281, a circulation control unit 282, and a switching control unit 283, and controls in such a way as to maintain the circulation of blood in the CRRT blood circuit 210 according to the degree of problems occurring in the ECMO system 100.

[0063] When the change rate of the flow rate of the ECMO system 100 measured by the flowmeter 114 exceeds a specified threshold value, the control unit 280 determines that some problem has occurred in the ECMO system 100. And when the control unit 280 determines that some problem has occurred, the water removal control unit 281 controls in such a way as to maintain the concentration of the blood circulating in the CRRT blood circuit 210 at a specified concentration. Specifically, the water removal control unit 281 controls the flow rate of the drainage pump 251 in such a way as to keep the concentration of the blood circulating in the CRRT blood circuit 210 constant.

[0064] For example, the water removal control unit 281 makes the flow rate of the drainage pump 251 equal to the flow rate of the replacement fluid pump 261, keeping the concentration of the circulating blood constant. Additionally, the water removal control unit 281 stops the replacement fluid pump 261 and the drainage pump 251 to stop the blood purification of the blood purifier 230, keeping the concentration of the circulating blood constant. Thereby, it is possible to prevent the concentration of the blood in the CRRT blood circuit 210 and suppress the occurrence of blood clots.

[0065] When the rate of change of the flow rate of the ECMO system 100 measured by the flowmeter 114 exceeds a specified threshold but the pressure measured by the pressure gauge is within a specified range, the control unit 280 determines that the problem that has occurred is minor. For example, when a problem occurs where the blood withdrawal amount slightly decreases due to partial occlusion of the blood inlet of the blood withdrawal cannula 111 or the like, but the ECMO blood pump 120 and the artificial lung 130 are not malfunctioning, although the flow rate of the ECMO system 100 measured by the flowmeter 114 will decrease, the pressure measured by the pressure gauge will not change significantly (remain within the specified range). In such a case, the control unit 280 determines that the problem that has occurred is minor.

[0066] When the control unit 280 determines that the problem is minor, the circulation control unit 282 reduces the flow rate of the blood purification pump 220 to a specified flow rate. In this case, at least a part of the liquid flowing in the blood return line 210b flows again into the blood withdrawal line 210a via a part of the ECMO system 100 (a part of the blood withdrawal line 110a). That is, at least a part of the blood (liquid) in the CRRT blood circuit 210 is recirculated.

[0067] Here, the specified flow rate refers to the flow rate at which the occurrence of thrombus can be inhibited within the CRRT blood circuit 210. Thus, the flow of blood at the connection part between the ECMO system 100 and the CRRT system 200 is not stopped, so when the problem of the ECMO system 100 is eliminated, the cooperation with the CRRT system 200 can be quickly restarted.

[0068] When the rate of change of the flow rate of the ECMO system 100 measured by the flowmeter 114 exceeds a specified threshold and the pressure measured by the pressure gauge exceeds a specified range, the control unit 280 determines that a serious problem has occurred in the ECMO system 100. For example, when the capacity of the ECMO blood pump 120 drops significantly, the flow rate of the ECMO system 100 measured by the flowmeter 114 drops significantly (the rate of change of the flow rate exceeds the specified threshold and decreases), and in addition, the pressure measured by the pressure gauge also drops significantly (decreases beyond the specified range). In addition, when the artificial lung 130 becomes blocked, the flow rate of the ECMO system 100 measured by the flowmeter 114 arranged on the downstream side of the artificial lung 130 drops significantly (the rate of change of the flow rate exceeds the specified threshold and decreases), and in addition, the pressure measured by the pressure gauge rises significantly (rises beyond the specified range). In such a case, the control unit 280 determines that the problem that has occurred is serious.

[0069] When the control unit 280 determines that the problem is the height, the switching control unit 283 performs control to occlude the flow path to the ECMO system 100 and switch to the bypass line 270, and recirculate all of the blood (liquid) in the CRRT blood circuit 210. Specifically, the switching control unit 283 occludes the clamp 215 of the blood return line 210b and opens the bypass clamp 270b of the bypass line 270 to switch the second flow path switching unit 272 and switch the flow path of the blood (liquid) flowing in the blood return line 210b to the bypass line 270. In addition, the switching control unit 283 occludes the clamp 212 of the blood extraction line 210a and opens the bypass clamp 270a of the bypass line 270 to switch the first flow path switching unit 271, stop the inflow of blood (liquid) from the ECMO system 100 to the blood extraction line 210a, and cause the blood (liquid) flowing in the bypass line 270 to flow into the blood extraction line 210a.

[0070] The various lines in the above-mentioned ECMO system 100 and CRRT system 200 are mainly composed of flexible soft tubes through which liquid can flow.

[0071] According to the above ECMO system 100 and CRRT system 200, a part of the blood flowing into the blood extraction line 110a of the ECMO system 100 from the vein of the subject (patient) flows into the blood extraction line 210a of the CRRT system 200 at a specified flow rate (the flow rate of the blood purification pump 220), and the rest is transported to the ECMO blood pump 120.

[0072] The blood transported to the blood extraction line 210a of the CRRT system 200 is introduced into the blood purifier 230 at a specified flow rate. After the blood purified by the blood purifier 230 is supplemented with the replenishing liquid from the replenishing liquid line 260 according to the amount of water removed, it is transported to the blood return line 210b.

[0073] The blood returned from the blood return line 210b to the blood extraction line 110a of the ECMO system 100 is transported to the ECMO blood pump 120 together with the blood flowing in the blood extraction line 110a, then transported to the artificial lung 130, and oxygen is added and carbon dioxide is removed. The blood sent out from the artificial lung 130 is returned to the artery or vein of the patient via the blood return line 110c and the blood delivery cannula 112.

[0074] When some problems occur in the ECMO system 100, the water removal control unit 281 controls the flow rate of the drainage pump 251 in such a way that the concentration of the blood circulating in the CRRT blood circuit 210 is kept constant. Thereby, the concentration of the blood in the CRRT blood circuit 210 can be prevented, and the occurrence of thrombus can be inhibited.

[0075] In the case where the problems occurring in the ECMO system 100 are minor, as Figure 3 shown, at least a part of the blood is recirculated through the blood drainage line 210a, the blood return line 210b, and a part of the ECMO system 100. At this time, the flow rate of the drainage pump 251 is controlled, and the concentration of the circulating blood is kept constant. Therefore, during the period of waiting for the recovery of the ECMO system 100, even if recirculation is performed in the CRRT system 200, concentration of the blood in the CRRT blood circuit 210 can be prevented, and thus the occurrence of thrombus can be suppressed. In addition, the blood flow at the connection part between the ECMO system 100 and the CRRT system 200 is not stopped, so that when the problems of the ECMO system 100 are eliminated, cooperation with the CRRT system 200 can be quickly restarted.

[0076] In addition, in the case where serious problems occur in the ECMO system 100, as Figure 4 shown, all of the blood is recirculated through the blood drainage line 210a, the blood return line 210b, and the bypass line 270. At this time, the flow rate of the drainage pump 251 is controlled, and the concentration of the circulating blood is kept constant. Therefore, the occurrence of thrombus in the CRRT blood circuit 210 can be suppressed. In addition, during the period of waiting for the recovery of the ECMO system 100, the CRRT system 200 is disconnected from the ECMO system 100 for recirculation, so that the recovery operation of the ECMO system 100 becomes easy.

[0077] <Second Embodiment>

[0078] Refer to Figures 5 to 8 to describe the second embodiment in detail.

[0079] The ECMO system 100A of the second embodiment is different from the first embodiment in that the first branch portion, the second branch portion, and the bypass line are provided not in the blood drainage line 110a but in the connection line 110b, and the blood purification system 200A is different from the first embodiment in that a flow rate adjustment jig is provided instead of the blood purification pump as a flow rate adjustment unit and a blood return pump is provided in the blood return line. Therefore, the same components as those described in the first embodiment are denoted by the same reference numerals and description thereof is omitted, and the differences will be described.

[0080] Figure 5 is a diagram showing a schematic configuration of the ECMO system 100A and the CRRT system 200A according to the second embodiment of the present invention. Figure 6 A block diagram showing the CRRT system 200A.

[0081] (ECMO system)

[0082] AsFigure 5 As shown, the ECMO system 100A includes an ECMO blood circuit 110A, an ECMO blood pump 120, an artificial lung 130, and a control unit 140.

[0083] The ECMO blood circuit 110A is a circuit for extracorporeal circulation of the patient's blood, and is composed of a blood extraction line 110a, a connection line 110b, and a blood return line 110c. One end of the blood extraction line 110a is connected to the blood extraction cannula 111, and the other end is connected to the ECMO blood pump 120.

[0084] One end of the connection line 110b is connected to the ECMO blood pump 120, and the other end is connected to the artificial lung 130. The connection line 110b has a first branch 110b1 and a second branch 110b2. Connectors such as three-way stopcocks are assembled at the first branch 110b1 and the second branch 110b2 respectively.

[0085] In addition, in the present embodiment, a bypass line 113 that bypasses the first branch 110b1 and the second branch 110b2 is provided in the connection line 110b.

[0086] (CRRT system)

[0087] As Figure 5 and Figure 6 shown, the CRRT system 200A includes a CRRT blood circuit 210, a flow adjustment clamp 220A as a flow adjustment unit, a blood return pump 216, a blood purifier 230, a dialysate supply line 240, a dialysate drainage line 250, a replenishing fluid line 260, a bypass line 270, and a control unit 280A.

[0088] The CRRT blood circuit 210 is a circuit for circulating the extracted blood, and is composed of a blood extraction line 210a and a blood return line 210b. One end (upstream end) of the blood extraction line 210a is connected to the first branch 110b1 provided in the connection line 110b of the ECMO system 100A, and the other end (downstream end) is connected to the blood purifier 230. A flow adjustment clamp 220A is provided in the blood extraction line 210a, a pressure gauge P1 is assembled on the upstream side of the flow adjustment clamp 220A, and a pressure gauge P2 is assembled on the downstream side of the flow adjustment clamp 220A. In addition, in order to monitor whether the flow rate delivered to the blood purifier 230 is normal, a flow meter 211 is assembled in the blood extraction line 210a.

[0089] One end (upstream end) of the blood return line 210b is connected to the blood purifier 230, and the other end (downstream end) is connected to the second branch 110b2 provided in the connection line 110b of the ECMO system 100.

[0090] In the blood return line 210b, a drip chamber 213, a liquid exhaustion sensor 214, a blood return pump 216, a clamp 215, and a pressure gauge P5 are assembled in order from the upstream side, and a pressure gauge P3 is assembled in the drip chamber 213. As the blood return pump 216, a known roller pump is used. In order to remove bubbles, coagulated blood, etc. mixed into the blood, the drip chamber 213 stores a certain amount of blood. In addition, the drip chamber 213 is used as a pressure buffer section for buffering the flow rate difference between the buffer flow rate adjustment clamp 220A and the blood return pump 216. Thus, even if the blood return line 210b is connected to the positive pressure section of the ECMO system 100A (downstream of the ECMO blood pump 120), the CRRT system 200A can operate at a low positive pressure. In addition, the pressure gauge P3 is used as a buffer section pressure gauge for measuring the pressure of the pressure buffer section. The pressure gauge P5 reflects the pressure at the connection section between the blood return line 210b and the ECMO blood circuit 110A, and thus can be used for monitoring the in-circuit pressure of the ECMO blood circuit 110A.

[0091] The flow rate adjustment clamp 220A is an adjustment clamp whose opening can be adjusted. By connecting the blood extraction line 210a to the positive pressure section of the ECMO system 100A (downstream of the ECMO blood pump 120), blood can be extracted at a specified flow rate. The extracted blood is transported to the blood purifier 230 through the blood extraction line 210a and then returned to the ECMO system 100A through the blood return line 210b. In the present embodiment, an example of using a flow rate adjustment clamp as the flow rate adjustment section 220A is shown, but a known roller pump can also be used. When a roller pump is used as the flow rate adjustment section 220A, blood can be extracted at a specified flow rate regardless of whether the blood extraction line 210a is connected to the positive pressure section or the negative pressure section (upstream of the ECMO blood pump 120) of the ECMO system 100A.

[0092] The bypass line 270 is a line that connects the blood extraction line 210a and the blood return line 210b and is used to disconnect the CRRT system 200A from the ECMO system 100A. The bypass line 270 is connected to the downstream side of the flow rate adjustment clamp 220A in the blood extraction line 210a and to the downstream side of the blood return pump 216 in the blood return line 210b. The bypass line 270 has a bypass clamp 270a near the connection section with the blood extraction line 210a and a bypass clamp 270b near the connection section with the blood return line 210b. The bypass clamp 270a and the flow rate adjustment clamp 220A provided in the blood extraction line 210a together constitute the first flow path switching section 271A. In addition, the bypass clamp 270b and the clamp 215 provided in the blood return line 210b together constitute the second flow path switching section 272.

[0093] In addition, in the present embodiment, although the first flow path switching unit 271A is composed of the flow rate adjustment unit 220A and the bypass clamp 270a, and the second flow path switching unit 272 is composed of two clamps, they may also be composed of a three-way stopcock or the like, respectively.

[0094] The control unit 280A is composed of an information processing device (computer). By executing a control program, it drives each pump included in the CRRT system 200A to control continuous hemodiafiltration (CHDF) for the blood flow rate, dialysate volume, and drainage volume of the blood purifier 230. In addition, the control unit 280A may also monitor the flow rates of the dialysate pump 241 arranged in the dialysate supply line 240, the drainage pump 251 arranged in the dialysate drainage line 250, and the supplementary fluid pump 261 arranged in the supplementary fluid line 260, and control the driving of each pump based on the flow rates measured by a metering unit (not shown) that measures the liquids (dialysate and supplementary fluid) flowing in the CRRT system 200A.

[0095] In addition, when the liquid exhaustion sensor 214 detects liquid exhaustion, the control unit 280A operates the clamp 215 to block the blood return line 210b, preventing air bubbles from mixing into the ECMO system 100A.

[0096] Moreover, in order to monitor the operating status of the ECMO system 100A, the control unit 280A obtains the measured value of the flow meter 114 and monitors the internal pressure of the circuit of the ECMO system 100A based on the measured value of the pressure gauge P1 or the pressure gauge P5. The control unit 280A grasps the occurrence of problems such as the instability of the circulation of the ECMO system 100A based on the measured value of the flow meter 114 and the measured value of the pressure gauge P1 or the pressure gauge P5. The control unit 280A includes a water removal control unit 281, a circulation control unit 282A, and a switching control unit 283A, and controls in such a way as to maintain the circulation of blood in the CRRT blood circuit 210 according to the degree of problems occurring in the ECMO system 100A. In addition, the control unit 280A also includes a flow rate control unit 284, and the flow rate control unit 284 adjusts the flow rates of the flow rate adjustment clamp 220A and the blood return pump 216 to control so that the measured value measured by the buffer pressure gauge P3 falls within a specified range.

[0097] When the rate of change of the flow rate of the ECMO system 100A measured by the flowmeter 114 exceeds a specified threshold value, the control unit 280A determines that some problem has occurred in the ECMO system 100A. And when it is determined by the control unit 280A that some problem has occurred, the ultrafiltration control unit 281 controls the CRRT system 200A in such a way that the concentration of the blood circulating in the CRRT blood circuit 210 is maintained at a specified concentration. Specifically, the ultrafiltration control unit 281 controls the flow rate of the drainage pump 251 in such a way that the concentration of the blood circulating in the CRRT blood circuit 210 remains constant.

[0098] When the rate of change of the flow rate of the ECMO system 100A measured by the flowmeter 114 exceeds a specified threshold value but the pressure measured by the pressure gauge is within a specified range, the control unit 280A determines that the problem that has occurred is minor.

[0099] When it is determined by the control unit 280A that the problem is minor, the circulation control unit 282A adjusts the opening degree of the flow rate adjustment clamp 220A and the output of the blood return pump 216 to decrease the flow rate of the blood flowing in the CRRT blood circuit 210 to a specified flow rate. In this case, at least a part of the liquid flowing in the blood return line 210b flows again into the blood extraction line 210a via a part of the ECMO system 100A (a part of the blood extraction line 110a). That is to say, at least a part of the blood (liquid) in the CRRT blood circuit 210 is recycled.

[0100] When the rate of change of the flow rate of the ECMO system 100A measured by the flowmeter 114 exceeds a specified threshold value and the pressure measured by the pressure gauge exceeds a specified range, the control unit 280A determines that a serious problem has occurred in the ECMO system 100A.

[0101] In the case where the control unit 280A determines that the problem is height, the switching control unit 283A performs control to occlude the flow path to the ECMO system 100 and switch to the bypass line 270, and recirculate all of the blood (liquid) within the CRRT blood circuit 210. Specifically, the switching control unit 283 occludes the clamp 215 of the blood return line 210b and opens the bypass clamp 270b of the bypass line 270 to switch the second flow path switching unit 272 and switch the flow path of the blood (liquid) flowing in the blood return line 210b to the bypass line 270. In addition, the switching control unit 283A sets the opening degree of the flow rate adjustment clamp 220A of the blood extraction line 210a to 0 and opens the bypass clamp 270a of the bypass line 270 to switch the first flow path switching unit 271A to stop the inflow of blood (liquid) from the ECMO system 100A into the blood extraction line 210a, and cause the blood (liquid) flowing in the bypass line 270 to flow into the blood extraction line 210a.

[0102] According to the above ECMO system 100A and CRRT system 200A, the blood taken out from the vein of the subject (patient) flows into the blood extraction line 110a of the ECMO system 100A, and a part of the blood flows into the blood extraction line 210a of the CRRT system 200A at a specified flow rate (the flow rate of the flow rate adjustment unit 220A) in the connection line 110b, and the rest is transported to the artificial lung 130.

[0103] The blood transported to the blood extraction line 210a of the CRRT system 200A is introduced into the blood purifier 230 at a specified flow rate. Here, the flow rate adjustment clamp 220A functions as a liquid feeding unit for transporting blood to the blood purifier 230, and functions as a pressure partition wall that prevents the high positive pressure transmitted from the ECMO blood circuit 110A from being transmitted to the blood purifier 230. The blood purified by the blood purifier 230 is supplemented with a replenishing liquid from the replenishing liquid line 260 according to the amount of water removed, and then transported to the blood return line 210b.

[0104] In the blood return line 210b, blood is stored within a specified range in the drip chamber 213 that serves as a pressure buffer section. The storage volume can be controlled by increasing and decreasing the set flow rate of the blood return pump 216. Specifically, the blood flow rate delivered from the downstream end of the blood purifier 230 becomes a blood flow rate that is slightly less than the set flow rate of the flow rate adjustment clamp 220A by the amount of water removed. Thus, when the internal pressure of the drip chamber 213 (the measured value of the pressure gauge P3) serving as the pressure buffer section exceeds the specified range, it is only necessary to make the set flow rate of the blood return pump 216 larger than the set flow rate of the flow rate adjustment clamp 220A. Additionally, when the internal pressure of the drip chamber 213 (the measured value of the pressure gauge P3) serving as the pressure buffer section is lower than the specified range, it is only necessary to make the set flow rate of the blood return pump 216 smaller than the set flow rate of the flow rate adjustment clamp 220A. By adjusting the amount of liquid stored in the drip chamber 213 in this way, the measured value of the pressure gauge P3 can be made to be within the specified range. Consequently, the upstream side of the blood return pump 216 can be set to a low positive pressure in the blood return line 210b, and thus the CRRT system 200A can be operated at a low positive pressure.

[0105] Since the blood return line 210b is equipped with the blood return pump 216, the internal pressure within the circuit on the downstream side of the blood return pump 216 can be increased to send blood to the positive pressure section (downstream side of the ECMO blood pump 120) of the ECMO system 100A. Here, the blood return pump 216 functions as a liquid delivery unit that delivers blood to the positive pressure section of the ECMO system 100A, and also functions as a pressure dividing wall that makes the upstream side a low positive pressure and the downstream side a high positive pressure.

[0106] The blood returned from the blood return line 210b to the connection line 110b of the ECMO system 100A is transported to the artificial lung 130 together with the blood flowing in the connection line 110b, and oxygen addition and carbon dioxide removal are performed. The blood sent out from the artificial lung 130 is returned to the patient's artery or vein via the blood return line 110c and the blood delivery cannula 112.

[0107] When certain problems occur in the ECMO system 100A, the drainage pump 251 is controlled by the water removal control unit 281 in such a way that the concentration of the blood circulating in the CRRT blood circuit 210 is maintained constant. Thereby, concentration of the blood in the CRRT blood circuit 210 is prevented, and the occurrence of blood clots is suppressed.

[0108] When the problems occurring in the ECMO system 100A are minor, as Figure 7As shown, at least a part of the blood is recirculated via the blood withdrawal line 210a, the blood return line 210b, and a part of the ECMO system 100. At this time, the flow rate of the drainage pump 251 is controlled, and the concentration of the circulating blood is maintained constant. Thus, during the period of waiting for the recovery of the ECMO system 100, even if recirculation is performed in the CRRT system 200A, concentration of the blood in the CRRT blood circuit 210 is prevented, and thus occurrence of thrombus can be suppressed. In addition, blood flow at the connection part between the ECMO system 100A and the CRRT system 200A is not stopped, and thus, when the problem of the ECMO system 100A is eliminated, cooperation with the CRRT system 200A can be quickly restarted.

[0109] In addition, in the case where a serious problem has occurred in the ECMO system 100A, as Figure 8 shown, all of the blood is recirculated via the blood withdrawal line 210a, the blood return line 210b, and the bypass line 270. At this time, the flow rate of the drainage pump 251 is controlled, and the concentration of the circulating blood is maintained constant. Thus, occurrence of thrombus in the CRRT blood circuit 210 can be suppressed. In addition, during the period of waiting for the recovery of the ECMO system 100A, the CRRT system 200A is disconnected from the ECMO system 100A for recirculation, and thus the recovery operation of the ECMO system 100A becomes easy.

[0110] In addition, according to the second embodiment, the blood purification system 200A includes a pressure buffer part (drip chamber 213) provided upstream of the blood return pump 216 in the blood return line 210b and capable of storing a prescribed amount of liquid, and a buffer part pressure gauge P3 for measuring the pressure of the pressure buffer part (drip chamber 213), and the control part 280A includes a flow rate control part 284 that controls the opening degree of the flow rate adjustment clamp 220A and the output of the blood return pump 216 so that the measured value of the buffer part pressure gauge P3 falls within a prescribed range. Thereby, even if the blood return line 210b of the blood purification system 200A is connected to the positive pressure part of the ECMO system 100A, the blood purification system 200A can be operated at a low positive pressure.

[0111] <Third Embodiment>

[0112] Refer to Figures 9 to 12 to explain the third embodiment in detail.

[0113] Figure 9 is a diagram showing a schematic configuration of the ECMO system 100A, the CRRT system 200B, and the intermediate system 300 according to the third embodiment of the present invention. The ECMO system 100A is the same as the ECMO system described in the second embodiment, and thus description thereof is omitted.

[0114] Figure 10 A block diagram showing the CRRT system 200B and the intermediate system 300.

[0115] (CRRT system)

[0116] As Figure 9 and Figure 10 shown, the CRRT system 200B includes a CRRT blood circuit 210B, a blood purification pump 220, a blood purifier 230, a dialysate supply line 240, a dialysate drainage line 250, a replacement fluid line 260, and a control unit 280B.

[0117] The CRRT blood circuit 210B is a circuit for circulating the withdrawn blood, and is composed of a blood withdrawal line 210a and a blood return line 210b. One end (upstream end) of the blood withdrawal line 210a is connected to the downstream end of an intermediate blood withdrawal line 310 of the intermediate system 300 described later, and the other end (downstream end) is connected to the blood purifier 230. The blood purification pump 220 is provided in the blood withdrawal line 210a. A pressure gauge P1 is installed on the upstream side of the blood purification pump 220, and a pressure gauge P2 is installed on the downstream side of the blood purification pump 220. One end (upstream end) of the blood return line 210b is connected to the blood purifier 230, and the other end (downstream end) is connected to the upstream end of an intermediate blood return line 320 of the intermediate system 300 described later.

[0118] The blood purification pump 220 withdraws blood from the ECMO system 100A via the intermediate blood withdrawal line 310. After the withdrawn blood is transported to the blood purifier 230 through the blood withdrawal line 210a, it is returned to the ECMO system 100A via the intermediate blood return line 320 through the blood return line 210b.

[0119] The control unit 280B is composed of an information processing device (computer), and drives each pump included in the CRRT system 200B by executing a control program, and controls continuous hemodiafiltration (CHDF) for the blood flow rate, dialysate volume, and drainage volume of the blood purifier 230. In addition, the control unit 280B can also monitor the flow rates of a dialysate pump 241 arranged in the dialysate supply line 240, a drainage pump 251 arranged in the dialysate drainage line 250, and a replacement fluid pump 261 arranged in the replacement fluid line 260, and control the driving of each pump based on the flow rates measured by a metering unit (not shown) that measures the liquids (dialysate and replacement fluid) flowing in the CRRT system 200B.

[0120] (Intermediate system)

[0121] As Figure 9 and Figure 10As shown, the intermediate system 300 includes an intermediate blood extraction line 310, a flow rate adjustment unit 311, an intermediate blood return line 320, a blood return pump 321, a blood extraction side pressure buffer unit 312, a blood extraction side detection unit 3121, a blood return side pressure buffer unit 322, a blood return side detection unit 3221, a control unit 330, a bypass line 340, and a notification unit 350 (refer to Figure 10 ).

[0122] The intermediate blood extraction line 310 is a line for extracting a part of the blood flowing in the connection line 110b of the ECMO system 100A and transporting it to the CRRT system 200B. One end (upstream end) of the intermediate blood extraction line 310 is connected to the first branch portion 110b1 provided in the connection line 110b of the ECMO system 100A, and the other end (downstream end) is connected to the upstream end of the CRRT system 200B. A flow rate adjustment unit 311 is provided in the intermediate blood extraction line 310. A pressure gauge P5 is assembled on the upstream side of the flow rate adjustment unit 311. In addition, in order to monitor whether the flow rate up to the connection portion (upstream end of the blood extraction line 210a) with the CRRT system 200 is normal, a flow meter 314 is assembled in the intermediate blood extraction line 310. In the present embodiment, an ultrasonic flow meter is used as the flow meter 314. As the flow meter 314, an optical flow meter or the like can also be used.

[0123] The flow rate adjustment unit 311 adjusts the flow rate of the blood flowing in the intermediate blood extraction line 310. The flow rate adjustment unit 311 is assembled at a position close to the upstream end in the intermediate blood extraction line 310. Thus, in the case where it is necessary to close the flow rate adjustment unit 311 and stop the blood flow, the amount of blood discarded due to coagulation can be reduced. The flow rate adjustment unit 311 is composed of a flow rate adjustment clamp capable of adjusting the opening degree. As the flow rate adjustment unit 311, a roller pump can also be used instead of the flow rate adjustment clamp. By adjusting the flow rate of the blood flowing in the intermediate blood extraction line 310 by the flow rate adjustment unit 311, the internal pressure in the downstream circuit can be adjusted.

[0124] The blood extraction side pressure buffer unit 312 is provided on the downstream side of the flow rate adjustment unit 311 in the intermediate blood extraction line 310 and can store a specified amount of liquid. In the present embodiment, as the blood extraction side pressure buffer unit 312, a reservoir composed of a soft bag is used.

[0125] It is desirable that the inlet for blood (liquid) to flow into the blood removal side pressure buffer section 312 (reservoir) and the outlet for blood (liquid) from the blood removal side pressure buffer section 312 (reservoir) are provided at the lower part so as to be filled with blood (liquid). For example, it is sufficient to form two openings at the lower part of the reservoir as the inlet and the outlet. By setting such a structure, when the storage amount of the reservoir decreases sharply due to some reasons, the risk of air being introduced into the intermediate blood removal line 310 on the downstream side of the reservoir can be reduced. In addition, a degassing line 3122 (see Figure 9 ). The degassing line 3122 is closed in principle during operation. In addition to being used to confirm the liquid level during priming, it is also used to degas the air retained in the reservoir during operation. In addition, a heating mechanism (not shown) may be provided in the blood removal side pressure buffer section 312. Thereby, the blood returned to the ECMO blood circuit 110 can be heated. In addition, as the blood removal side pressure buffer section 312, a small container (such as a pillow) made of soft raw materials may be used instead of the reservoir.

[0126] In addition, a bypass line 313 for bypassing the blood removal side pressure buffer 312 may be provided in the intermediate blood removal line 310. The bypass line 313 and the connecting portion of the intermediate blood removal line 310 are connected by, for example, a Y-shaped connector (not shown).

[0127] By providing the bypass line 313, when operating the intermediate system 300, the user can select whether to use the blood removal side pressure buffer 312 for pressure buffering, or not to use the blood removal side pressure buffer 312 and not to use the bypass line 313 for pressure buffering. When the blood removal side pressure buffer 312 is not used, the priming volume can be reduced accordingly.

[0128] The blood removal side detection unit 3121 is assembled to the blood removal side pressure buffer unit 312 to detect the storage state of the blood removal side pressure buffer unit 312. In this embodiment, a weight meter is used as an example of the blood removal side detection unit 3121 to measure the weight (storage state) of the liquid stored in the blood removal side pressure buffer unit 312 (reservoir). In addition, in the case where an air layer is provided in the reservoir, a pressure gauge may be used as the blood removal side detection unit 3121 to measure the internal pressure that changes according to the storage state of the reservoir. In addition, in the case where a small container such as a pillow is used as the blood removal side pressure buffer unit 312, it is sufficient to use a pressure gauge as the blood removal side detection unit 3121 to detect the expansion and contraction corresponding to the internal pressure of the small container.

[0129] One end (downstream end) of the intermediate blood return line 320 is connected to the second branch 110b2 of the connection line 110b provided in the ECMO system 100A, and the other end (upstream end) is connected to the downstream end of the CRRT blood circuit 210 (blood return line 210b). In the intermediate blood return line 320, a blood return side pressure buffer 322 and a blood return pump 321 are arranged in sequence from the upstream side. In addition, in the intermediate blood return line 320, a drip chamber 323, a liquid exhaustion sensor 324, and a clamp 325 are assembled in sequence on the downstream side of the blood return pump 321. A pressure gauge P6 is assembled on the drip chamber 323. In order to remove bubbles, coagulated blood, etc. mixed into the intermediate blood return line 320, the drip chamber 323 stores a certain amount of blood. The clamp 325 is assembled at a position near the downstream end in the intermediate blood return line 320. The pressure gauge P6 measures the internal pressure in the circuit on the downstream side of the blood return pump 321 in the intermediate blood return line 320.

[0130] The blood return pump 321 is a pump for sending the blood flowing in the intermediate blood return line 320 to the positive pressure part of the ECMO system 100A. As the blood return pump 321, a known roller pump can be used.

[0131] The blood return side pressure buffer 322 is arranged on the upstream side of the blood return pump 321 in the intermediate blood return line 320 and can store a specified amount of liquid. In the present embodiment, as the blood return side pressure buffer 322, a reservoir composed of a soft bag is used in the same way as the blood extraction side pressure buffer 312.

[0132] The blood return side detection part 3221 is assembled on the blood return side pressure buffer 322 to detect the storage state of the blood return side pressure buffer 322. The structure of the blood return side detection part 3221 can use the same structure as the blood extraction side detection part 3121.

[0133] The bypass line 340 is a line connecting the intermediate blood extraction line 310 and the intermediate blood return line 320, and is used to disconnect the CRRT system 200B and the intermediate system 300 from the ECMO system 100A. The bypass line 340 is connected to the downstream side of the flow rate adjustment part 311 in the intermediate blood extraction line 310 and is connected between the liquid exhaustion sensor 324 and the clamp 325 in the intermediate blood return line 320. The bypass line 340 has a bypass clamp 340a near the connection part with the intermediate blood extraction line 310 and a bypass clamp 340b near the connection part with the intermediate blood return line 320. The bypass clamp 340a and the flow rate adjustment part 311 provided in the intermediate blood extraction line 310 together constitute the first flow path switching part 341. In addition, the bypass clamp 340b and the clamp 325 provided in the intermediate blood return line 320 together constitute the second flow path switching part 342.

[0134] In addition, in the present embodiment, although the first flow path switching unit 341 is constituted by the flow rate adjustment unit 311 and the bypass clamp 340a, and the second flow path switching unit 342 is constituted by two clamps, they may also be constituted by a three-way stopcock or the like, respectively.

[0135] The control unit 330 is constituted by an information processing device (computer), and drives and controls each pump and each clamp included in the intermediate system 300 by executing a control program. In addition, the control unit 330 controls the opening degree of the flow rate adjustment clamp serving as the flow rate adjustment unit 311 according to the storage state (weight) detected by the blood removal side detection unit 3121 (weighing scale), and adjusts the flow rate of the intermediate blood removal line 310 so that the storage amount of the blood stored in the blood removal side pressure buffer unit 312 (reservoir) falls within a specified range. The flow rate of the blood taken out from the connection line 110b may be set by increasing and decreasing it based on the flow rate of the blood purification pump 220.

[0136] Moreover, when the control unit 330 detects liquid exhaustion by the liquid exhaustion sensor 324, the control unit 330 operates the clamp 325 to block the intermediate blood return line 320, thereby preventing air bubbles from being mixed into the ECMO system 100A.

[0137] Moreover, in order to monitor the operation status of the ECMO system 100A, the control unit 330 acquires the measurement value of the flow meter 114, and monitors the internal pressure of the circuit of the ECMO system 100A based on the measurement value of the pressure gauge P5 or the pressure gauge P6. The control unit 330 grasps the occurrence of problems such as the instability of the circulation of the ECMO system 100A based on the measurement value of the flow meter 114 and the measurement value of the pressure gauge P5 or the pressure gauge P6.

[0138] The control unit 330 includes a circulation control unit 331 and a switching control unit 332. In the present embodiment, when the change rate of the flow rate of the ECMO system 100 measured by the flow meter 114 exceeds a specified threshold value, the control unit 330 determines that some problem has occurred in the ECMO system 100. And the notification unit 350 is made to notify the occurrence of this problem.

[0139] Specifically, the control unit 330 causes the notification unit 350 to notify that some problem has occurred in the ECMO system 100 and stops the blood purification of the blood purifier 230 to keep the concentration of the blood flowing in the CRRT blood circuit 210 constant.

[0140] In addition, when the rate of change of the flow rate of the ECMO system 100A measured by the flowmeter 114 exceeds a specified threshold value but the pressure measured by the pressure gauge is within a specified range, the control unit 330 determines that the problem that has occurred is minor. In this case, the circulation control unit 331 reduces the flow rate of the blood purification pump 220 to a specified flow rate. At this time, at least a part of the liquid flowing in the intermediate blood return line 320 flows again into the intermediate blood extraction line 310 via a part of the ECMO system 100A (a part of the connection line 110b). That is, at least a part of the blood (liquid) is recirculated in the intermediate system 300 and the CRRT blood circuit 210.

[0141] When the rate of change of the flow rate of the ECMO system 100A measured by the flowmeter 114 exceeds a specified threshold value and the pressure measured by the pressure gauge exceeds a specified range, the control unit 330 determines that a serious problem has occurred in the ECMO system 100A. In this case, the switching control unit 332 performs control to block the flow path to the ECMO system 100A and switch to the bypass line 340, and recirculate all of the blood (liquid) in the intermediate blood extraction line 310, the CRRT blood circuit 210, the intermediate blood return line 320, and the bypass line 340. Specifically, the switching control unit 332 closes the clamp 325 of the intermediate blood return line 320 and opens the bypass clamp 340b of the bypass line 340 to switch the second flow path switching unit 342 and switch the flow path of the blood (liquid) flowing in the intermediate blood return line 320 to the bypass line 340. At the same time, the switching control unit 332 sets the flow rate of the flow rate adjustment unit 311 of the intermediate blood extraction line 310 to 0 and opens the bypass clamp 340a of the bypass line 340 to switch the first flow path switching unit 341 to stop the inflow of the blood (liquid) from the ECMO system 100A into the intermediate blood extraction line 310, and cause the blood (liquid) flowing in the bypass line 340 to flow into the intermediate blood extraction line 310.

[0142] In addition, in the present embodiment, the control unit 330 further includes a flow rate control unit 333, and the flow rate control unit 333 adjusts the flow rates of the flow rate adjustment unit 311 and the blood return pump 321 so that the weight of the liquid stored in the blood return side pressure buffer unit is within a specified range.

[0143] Each of the various lines in the above-described ECMO system 100A, CRRT system 200B, and intermediate system 300 is mainly composed of a flexible soft pipe through which a liquid can flow.

[0144] According to the above ECMO system 100A, CRRT system 200B, and intermediate system 300, the blood taken out from the vein of the subject (patient) flows into the blood withdrawal line 110a of the ECMO system 100A, and a part of the blood flows into the intermediate blood withdrawal line 310 of the intermediate system 300 at a specified flow rate in the connection line 110b, and the rest is delivered to the artificial lung 130.

[0145] The blood delivered to the intermediate system 300 stores blood within a specified range in the blood withdrawal side pressure buffer section 312. The storage amount can be controlled by increasing and decreasing the set flow rate of the flow rate adjustment section 311. Specifically, since the blood flow rate flowing out from the downstream side of the blood withdrawal side pressure buffer section 312 becomes the set flow rate of the blood purification pump 220, when the storage amount in the blood withdrawal side pressure buffer section 312 exceeds the specified range, it is only necessary to make the set flow rate of the flow rate adjustment section 311 smaller than the set flow rate of the blood purification pump 220. In addition, when the storage amount in the blood withdrawal side pressure buffer section 312 is lower than the specified range, it is only necessary to make the set flow rate of the flow rate adjustment section 311 larger than the set flow rate of the blood purification pump 220. Thus, a specified amount of blood is stored in the blood withdrawal side pressure buffer section 312, and therefore the blood withdrawal side pressure buffer section 312 provided in the intermediate blood withdrawal line 310 can reduce the pressure in the circuit.

[0146] The blood stored in the blood withdrawal side pressure buffer section 312 is introduced into the blood purifier 230 by the blood purification pump 220. Here, due to the blood withdrawal side pressure buffer section 312, the pressure in the circuit becomes a low positive pressure, so the upstream side of the blood purification pump 220 becomes a low positive pressure.

[0147] In the blood purifier 230, water and waste are removed via the dialysis membrane, and the purified blood is led out from the blood purifier 230. After the blood purified by the blood purifier 230 is supplemented with a replenishing solution from the replenishing solution line 260 according to the amount of water removed, it is delivered to the intermediate blood return line 320 of the intermediate system 300.

[0148] In the middle blood return line 320, blood is stored within a specified range in the blood return side pressure buffer portion 322. The storage volume can be controlled by increasing and decreasing the set flow rate of the blood return pump 321. Specifically, the blood flow rate delivered from the downstream end of the CRRT system 200B becomes a blood flow rate that is slightly smaller than the set flow rate of the blood purification pump 220 by the amount of water removed. Thus, when the storage volume in the blood return side pressure buffer portion 322 exceeds the specified range, it is only necessary to make the set flow rate of the blood return pump 321 larger than the set flow rate of the blood purification pump 220. Additionally, when the storage volume in the blood return side pressure buffer portion 322 is below the specified range, it is only necessary to make the set flow rate of the blood return pump 321 smaller than the set flow rate of the blood purification pump 220. Thereby, a specified amount of blood is stored in the blood return side pressure buffer portion 322, and thus the in-line pressure can be reduced by the blood return side pressure buffer portion 322 provided in the middle blood return line 320. Consequently, the downstream end of the CRRT system 200B can be set to a low positive pressure, and thus the CRRT system 200B can be operated at a low positive pressure.

[0149] Since the middle blood return line 320 is equipped with the blood return pump 321, it can boost the in-line pressure reduced by the blood return side pressure buffer portion 322 and send the blood to the positive pressure section (downstream side of the ECMO blood pump 120) of the ECMO system 100A. Here, the blood return pump 321 functions as a liquid delivery unit for delivering blood to the positive pressure section of the ECMO system, and also functions as a pressure dividing wall that makes the upstream side a low positive pressure and the downstream side a high positive pressure.

[0150] The blood returned from the middle blood return line 320 of the intermediate system 300 to the connection line 110b of the ECMO system 100A is transported to the artificial lung 130 together with the blood flowing in the connection line 110b, where oxygen addition and carbon dioxide removal are performed. The blood sent out from the artificial lung 130 is returned to the patient's artery or vein via the blood return line 110c and the blood delivery cannula 112.

[0151] In the case where some problem occurs in the ECMO system 100A, if an alarm is given by the alarm unit 350 and the concentration of the blood flowing in the CRRT blood circuit 210 is kept constant based on this alarm, then the concentration of the blood in the CRRT system 200B can be prevented from increasing, and the occurrence of blood clots can be inhibited.

[0152] In the case where the problem occurring in the ECMO system 100 is minor, as Figure 11As shown, at least a part of the blood is recirculated through the CRRT blood circuit 210, the intermediate blood extraction line 310, the intermediate blood return line 320, and a part of the ECMO system 100A. Thus, during the waiting period for the recovery of the ECMO system 100A, even if recirculation occurs in the intermediate system 300 and the CRRT system 200B, blood concentration can be prevented, and thus the occurrence of thrombus can be suppressed. In addition, the blood flow at the connection part between the ECMO system 100 and the intermediate system 300 is not stopped, so that when the problems of the ECMO system 100 are eliminated, the cooperation with the CRRT system 200 can be quickly restarted.

[0153] In addition, when a serious problem occurs in the ECMO system 100A, as Figure 12 shown, all of the blood is recirculated through the intermediate blood extraction line 310, the CRRT blood circuit 210, the intermediate blood return line 320, and the bypass line 340. At this time, if notification is made by the notification unit 350 and the concentration of the blood flowing in the CRRT blood circuit 210 is kept constant according to this notification, blood concentration in the intermediate system 300 and the CRRT system 200B can be prevented, and the occurrence of thrombus can be suppressed. In addition, during the waiting period for the recovery of the ECMO system 100A, the intermediate system 300 and the CRRT system 200A are disconnected from the ECMO system 100A for recirculation, so that the recovery operation of the ECMO system 100A becomes easier.

[0154] As described above, the preferred embodiments of the CRRT system and the intermediate system of the present invention have been described, but the present invention is not limited to the above embodiments and can be appropriately changed.

[0155] Explanation of Reference Numerals

[0156] 100, 100A Extracorporeal Membrane Oxygenation (ECMO) system

[0157] 110, 110A Blood circuit

[0158] 110a Blood extraction line

[0159] 110b Connection line

[0160] 120 ECMO blood pump

[0161] 130 Artificial lung

[0162] 200, 200A, 200B Continuous Renal Replacement Therapy (CRRT) system

[0163] 210, 210B Blood circuit

[0164] 210a Blood extraction line

[0165] 210b Blood return line

[0166] 220 Blood purification pump

[0167] 230 Blood purifier

[0168] 300 Intermediate system

[0169] 310 Intermediate blood extraction line

[0170] 311 Flow adjustment section

[0171] 312 Blood extraction side pressure buffer section

[0172] 320 Intermediate blood return line

[0173] 321 Blood return pump

[0174] 322 Blood return side pressure buffer section

[0175] 3121 Blood extraction side detection section

[0176] 3221 Blood return side detection section.

Claims

1. A blood purification system is a blood purification system connected to an extracorporeal membrane lung system. The extracorporeal membrane lung system has an ECMO blood pump and an artificial lung arranged downstream of the ECMO blood pump. The blood purification system is characterized by comprising: A blood extraction line, whose upstream end is connected to the extracorporeal membrane lung system; A flow rate adjustment unit, which is arranged on the blood extraction line to adjust the flow rate of the blood extraction line; A blood purifier, which is connected to the downstream end of the blood extraction line; A blood return line, whose upstream end is connected to the blood purifier and whose downstream end is connected to the extracorporeal membrane lung system; A flow meter, which measures the flow rate of the extracorporeal membrane lung system; and A control unit, The control unit comprises: A water removal control unit, which maintains the concentration of the liquid flowing through the blood purification system at a specified concentration when the change rate of the flow rate measured by the flow meter exceeds a specified threshold.

2. The blood purification system according to claim 1, wherein, It further comprises: a pressure gauge, which measures the pressure at the connection part between the extracorporeal membrane lung system and the blood extraction line or the blood return line, The control unit further comprises: a circulation control unit, which reduces the flow rate of the flow rate adjustment unit to a specified flow rate when the change rate of the flow rate measured by the flow meter exceeds a specified threshold and the pressure measured by the pressure gauge is within a specified range.

3. The blood purification system according to claim 2, wherein, It further comprises: A bypass line, which connects the upstream side of the blood purification pump in the blood extraction line to the blood return line; A first flow path switching unit, which is arranged near the connection part between the blood extraction line and the bypass line; and A second flow path switching unit, which is arranged near the connection part between the blood return line and the bypass line, The control unit comprises: A switching control unit, which switches the second flow path switching unit to switch the flow path of the liquid flowing through the blood return line to the bypass line, switches the first flow path switching unit to stop the inflow of the liquid from the extracorporeal membrane lung system to the blood extraction line, and makes the liquid flowing through the bypass line flow into the blood extraction line when the change rate of the flow rate measured by the flow meter exceeds a specified threshold and the pressure measured by the pressure gauge exceeds a specified range.

4. The blood purification system according to claim 1 or 3, wherein, It further comprises a blood return pump arranged on the blood return line, The upstream end of the blood extraction line is connected to the downstream side of the ECMO blood pump in the extracorporeal membrane lung system, The downstream end of the blood return line is connected to the downstream side of the ECMO blood pump in the extracorporeal membrane lung system.

5. The blood purification system according to claim 4, wherein, It further comprises: A pressure buffer unit, which is arranged upstream of the blood return pump in the blood return line and can store a specified amount of liquid; and A buffer unit pressure gauge, which measures the pressure of the pressure buffer unit, The control unit further includes a flow control unit that adjusts the flow rates of the flow rate adjustment unit and the blood return pump so as to control the measured value of the buffer unit pressure gauge within a specified range.

6. An intermediate system is an intermediate system provided at the connection part between an extracorporeal membrane type artificial lung system and a blood purification system. The extracorporeal membrane type artificial lung system has an ECMO blood pump and an artificial lung disposed downstream of the ECMO blood pump. The blood purification system has a blood purification pump, a blood purifier disposed downstream of the blood purification pump, a drainage line for discharging filtrate from the blood purifier, and a drainage pump provided in the drainage line. The intermediate system is characterized by including: An intermediate blood extraction line, whose upstream end is connected to the downstream side of the ECMO blood pump in the extracorporeal membrane type artificial lung system, and whose downstream end is connected to the upstream end of the blood purification system; A flow rate adjustment unit that is provided in the intermediate blood extraction line and adjusts the flow rate of the intermediate blood extraction line; An intermediate blood return line, whose upstream end is connected to the downstream end of the blood purification system, and whose downstream end is connected to the downstream side of the ECMO blood pump in the extracorporeal membrane type artificial lung system; A blood return pump that is provided in the intermediate blood return line; A flow meter that measures the flow rate of the extracorporeal membrane type artificial lung system; An alarming unit; and A control unit, The control unit When the change rate of the flow rate measured by the flow meter exceeds a specified threshold value, it is determined that a problem has occurred in the extracorporeal membrane type artificial lung system, and the alarming unit is made to alarm the occurrence of the problem.

7. The intermediate system according to claim 6, wherein, It further includes: A bypass line that connects the downstream side of the flow rate adjustment unit in the intermediate blood extraction line to the intermediate blood return line; A first flow path switching unit that is disposed near the connection part of the intermediate blood extraction line and the bypass line; A second flow path switching unit that is disposed near the connection part of the intermediate blood return line and the bypass line; and A pressure gauge that measures the pressure at the connection part of the extracorporeal membrane type artificial lung system and the intermediate blood extraction line or the intermediate blood return line, The control unit includes: A switching control unit that, when the change rate of the flow rate measured by the flow meter exceeds a specified threshold value and the pressure measured by the pressure gauge exceeds a specified range, switches the second flow path switching unit to switch the flow path of the liquid flowing in the intermediate blood return line to the bypass line, switches the first flow path switching unit to stop the inflow of the liquid from the extracorporeal membrane type artificial lung system to the intermediate blood extraction line, and makes the liquid flowing in the bypass line flow into the intermediate blood extraction line.

Images