Blockage detection device for fluid infusion passage in hemodialysis device

Abstract

A blockage detection device for a fluid replacement passage in a hemodialysis device detects the presence or absence of blockage in a fluid replacement passage of the hemodialysis device. The control component executes a first action of operating a dialysate pump at a predetermined set flow rate while filling a supply chamber with dialysate and obtaining the total amount discharge time until the dialysate in the supply chamber disappears. Next, the fluid replacement pump is operated through a second action to discharge a portion of the dialysate filled in the supply chamber into the blood circuit, and then, the remaining amount discharge time is obtained through a third action until the residual dialysate remaining in the supply chamber disappears using the dialysate pump. At this time, when the remaining amount discharge time is consistent with the total amount discharge time, it can be determined through the second action that the dialysate filled in the supply chamber is not discharged into the blood circuit at all, and therefore it can be determined through the fourth action that the fluid replacement passage is blocked. The presence or absence of blockage in the fluid replacement passage can be detected without adding a special structure.

Description

Technical Field

[0001] The present invention relates to a fluid replacement channel used in a hemodialysis device, and more particularly, to a blockage detection device for detecting the presence or absence of blockage in the fluid replacement channel. Background Art

[0002] Conventionally, a hemodialysis apparatus including a fluid replacement channel is known (Patent Document 1 and Patent Document 2).

[0003] The hemodialysis device described in Patent Document 1 comprises: a dialysate chamber, which is divided into a supply chamber and a recovery chamber by a diaphragm; a dialysate supply passage, which connects the above-mentioned supply chamber with a dialyzer; a dialysate recovery passage, which connects the above-mentioned dialyzer with the recovery chamber; a dialysate pump, which is arranged in the above-mentioned dialysate recovery passage; a blood circuit, which is connected to the above-mentioned dialyzer; a fluid infusion passage, which is connected to the above-mentioned dialysate passage and the blood circuit; a fluid infusion pump, which is arranged in the above-mentioned fluid infusion passage; and a control component, which controls the above-mentioned dialysate pump and the fluid infusion pump.

[0004] In the hemodialysis apparatus described in Patent Document 2, the presence or absence of blockage of the above-mentioned fluid replacement path is detected by detecting a pressure increase on the blood circuit side.

[0005] Prior Art Literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent No. 5858868

[0008] Patent Document 2: Japanese Patent Application Publication No. 2016-129646

[0009] The above-mentioned fluid infusion passage is closed by an opening and closing member such as forceps in the preparation stage of dialysis treatment, and the dialysis treatment is started after the fluid infusion passage is opened.

[0010] However, there are cases where the dialysis treatment is started in a state where the fluid infusion path is forgotten to be opened, and in this case, the fluid cannot be infused into the blood circuit.

[0011] Therefore, Patent Document 2 discloses a problem when dialysis is performed in a state where a fluid replacement passage is blocked, and a solution to the problem by detecting a pressure increase on the blood circuit side. Summary of the invention

[0012] The present invention provides a clogging detection device capable of detecting the presence or absence of clogging of a fluid replacement passage by a means different from that of Patent Document 2.

[0013] The invention of technical solution 1 is a blockage detection device for a fluid infusion passage in a hemodialysis device, the hemodialysis device comprising: a dialysate chamber, the dialysate chamber being divided into a supply chamber and a recovery chamber by a diaphragm; a dialysate supply passage, the dialysate supply passage connecting the supply chamber with a dialyzer; a dialysate recovery passage, the dialysate recovery passage connecting the dialyzer with the recovery chamber; a dialysate pump, the dialysate pump being arranged in the dialysate recovery passage; a blood circuit, the blood circuit being connected to the dialyzer; a fluid infusion passage, the fluid infusion passage being connected to the dialysate passage and the blood circuit; a fluid infusion pump, the fluid infusion pump being arranged in the fluid infusion passage; and a control component, the control component controlling the dialysate pump and the fluid infusion pump, characterized in that

[0014] The control component performs the first action, the second action and the third action, and also performs the fourth action.

[0015] In the first operation, the dialysate pump is operated at a predetermined set flow rate, and a total discharge time is obtained, which is a time until the dialysate filling the supply chamber disappears.

[0016] In the second operation, a portion of the dialysate filled in the supply chamber is discharged by the fluid replacement pump.

[0017] In the third operation, the dialysate pump is operated at a predetermined set flow rate, and a residual discharge time is obtained, which is the time until the residual dialysate remaining in the supply chamber disappears after the second operation is completed.

[0018] In the fourth operation, when the difference between the remaining amount discharge time and the total amount discharge time is within a required tolerance range, it is determined that the fluid replacement passage is clogged.

[0019] As in the invention of claim 2, by actually operating the dialysate pump at a predetermined set flow rate and measuring the time until the dialysate filling the supply chamber disappears, the total amount discharge time in the first operation can be acquired.

[0020] In addition, as in the invention of claim 3, it is preferred that the amount of dialysate discharged from the supply chamber by the infusion pump in the second operation is approximately half of the amount of dialysate filled in the supply chamber. This is because, when the amount discharged from the supply chamber by the infusion pump is small, the difference between the remaining amount discharge time and the total amount discharge time becomes small, and when the discharge amount is large, the set flow rate of the infusion pump is generally set to be smaller than the set flow rate of the dialysate pump, and therefore, the time required for the blockage detection of the infusion passage becomes longer.

[0021] According to the above configuration, first, through the first operation, the total amount of discharge time until the dialysate filling the supply chamber disappears when the dialysate pump is operated at a predetermined set flow rate can be acquired.

[0022] Then, through the second action, the infusion pump can be operated to discharge a part of the dialysate filled in the supply chamber. At this time, as long as the infusion passage is not blocked, a part of the dialysate should actually be discharged from the supply chamber to the outside. On the other hand, if the infusion passage is completely blocked, even if the infusion pump is operated, the dialysate in the supply chamber cannot be discharged to the outside, and the amount of dialysate in the supply chamber is the total amount that remains filled in the supply chamber.

[0023] Then, through the third action, the dialysate pump can be used to completely discharge the residual dialysate remaining in the supply chamber after the second action. At this time, the remaining discharge time required for the discharge is measured. As described above, if the above-mentioned fluid replacement passage is completely blocked, the amount of dialysate in the supply chamber after the second action is the total amount required to keep the state of being filled in the supply chamber unchanged. Therefore, the remaining discharge time in the third action should be consistent with the total discharge time based on the first action.

[0024] Therefore, through the fourth operation, when the difference between the remaining amount discharge time and the total amount discharge time is within a required tolerance range, the control means can determine that the fluid replacement passage is clogged.

[0025] Furthermore, in the present invention, since the structure of a conventional hemodialysis apparatus can be used as it is, it can be manufactured at low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a circuit diagram of the hemodialysis device of this embodiment.

[0027] Figure 2 This is a circuit diagram for explaining the first operation and the third operation of discharging the dialysate in the supply chamber 21 a to the recovery chamber 21 b by the dialysate pump 27 .

[0028] Figure 3 This is a circuit diagram for explaining a second operation in which the dialysate in the supply chamber 21 a is discharged to the blood circuit 3 via the fluid replacement passage 6 by the fluid replacement pump 19 .

[0029] Description of Reference Numerals

[0030] 1Hemodialysis device 2Dialex

[0031] 3 blood circuit 4 dialysate circuit

[0032] 6 fluid infusion channel 19 fluid infusion pump

[0033] 21, 22 Dialysate chamber 21a, 22a Supply chamber

[0034] 21b, 22b Recovery chamber 24 Dialysate supply passage

[0035] 25 dialysate recovery channel 27 dialysate pump

[0036] 28 Flow switch C control components

[0037] D Diaphragm DETAILED DESCRIPTION

[0038] Hereinafter, the present invention will be described with reference to the embodiments shown in the drawings. Figure 1 In the embodiment, a hemodialysis apparatus 1 for performing hemodialysis includes a dialyzer 2 for performing hemodialysis, a blood circuit 3 connected to the dialyzer 2 , and a dialysate circuit 4 connected to the dialyzer 2 .

[0039] The hemodialysis apparatus 1 of the present embodiment can perform online HDF and HF for supplying fresh dialysate to the patient via the blood circuit 3 , and includes a fluid replacement passage 6 branched from the blood circuit 3 and connected to the dialysate circuit 4 .

[0040] The blood circuit 3 includes an arterial side passage 11 connected to the patient's artery and connected to one end of the dialyzer 2, and a venous side passage 12 connected to the vein and connected to the other end of the dialyzer 2. In the illustrated embodiment, the fluid replacement passage 6 is connected so as to branch from the arterial side passage 11. Figure 1 As shown by the dotted line, the above-mentioned fluid replacement passage 6 is connected so as to branch from the venous side passage 12.

[0041] The arterial side passage 11 is provided with a puncture needle 11a for puncturing a patient, a clamping component 13A for opening and closing the arterial side passage 11, a syringe 14 containing a coagulation inhibitor, a blood pump 15 composed of a tube pump (peristaltic pump) for conveying blood, and a drip chamber 16A for removing air from the blood. A pressure gauge 17A is provided in the drip chamber 16A.

[0042] Although not shown in the figure, the plunger 14 a of the syringe 14 is provided with a pressing member for pressing the plunger 14 a , and the plunger 14 a is pressed by the pressing member, so that a blood coagulation inhibitor such as heparin can be supplied to the arterial channel 11 .

[0043] The venous passage 12 is provided with a drip chamber 16B for removing air from blood, a clamping member 13B for opening and closing the venous passage 12, and a puncture needle 12a for puncturing a patient. The drip chamber 16B is provided with a pressure gauge 17B.

[0044] As described above, the fluid replacement passage 6 is connected to the drip chamber 16A in the arterial side passage 11, and the fluid replacement passage 6 is replaced together with the dialyzer 2 and the blood circuit 3 every time dialysis treatment is performed.

[0045] In addition, a connector 6a for connecting to a liquid replacement port 31 described later is provided at the upstream end of the fluid infusion passage 6, and a fluid infusion pump 19 composed of a tube pump similar to the above-mentioned blood pump 15, and an opening and closing component 20 such as a forceps, a clamp or a Robert clamp for opening and closing the fluid infusion passage 6 are provided in the fluid infusion passage 6.

[0046] Furthermore, as described above, the infusion passage 6 may be connected to the drip chamber 16B in the venous passage 12 according to the judgment of the attending physician. In addition, the opening and closing member 20 is not limited to the position shown in the figure, and may be provided at any position as long as it is provided on the infusion passage 6.

[0047] The dialysate circuit 4 includes: a first dialysate chamber 21 and a second dialysate chamber 22 of the same shape for supplying or discharging dialysate; a fluid supply passage 23 for supplying fresh dialysate to the first dialysate chamber 21 and the second dialysate chamber 22; a dialysate supply passage 24 for supplying fresh dialysate from the first dialysate chamber 21 and the second dialysate chamber 22 to the dialyzer 2; a dialysate recovery passage 25 for recovering used dialysate that has passed through the dialyzer 2 to the first dialysate chamber 21 and the second dialysate chamber 22; and a drainage passage 26 for discharging used dialysate from the first dialysate chamber 21 and the second dialysate chamber 22 to a drainage tank (not shown).

[0048] In the present embodiment, the pump and the opening and closing valve described below constituting the dialysate circuit 4 constitute dialysate circulation means for circulating the dialysate in the dialysate circuit 4 , and these are controlled by the control means C.

[0049] The interior of the first dialysate chamber 21 and the second dialysate chamber 22 are divided into two chambers by a diaphragm D, respectively, to form supply chambers 21a and 22a for storing fresh dialysate and recovery chambers 21b and 22b for storing used dialysate.

[0050] The liquid supply passage 23 is provided with a liquid supply pump (not shown) for conveying fresh dialysate, and the downstream portion thereof branches in two directions and is connected to the supply chambers 21a and 22a of the first and second dialysate chambers 21 and 22. Liquid supply valves V1 and V2 are provided at the branch portions, respectively.

[0051] The upstream portion of the dialysate supply passage 24 branches in two directions and is connected to the supply chambers 21a and 22a of the first dialysate chamber 21 and the second dialysate chamber 22, respectively, and a connector 24a connected to the dialyzer 2 is provided at the downstream end. In addition, supply valves V3 and V4 are provided at the branch portions, respectively, and a flow switch 28 for detecting the presence or absence of dialysate circulation is provided at a position downstream of the branch portion.

[0052] A connector 25a connected to the dialyzer 2 is provided at the upstream end of the dialysate recovery passage 25, and a downstream portion branches in two directions and is connected to the recovery chambers 21b and 22b of the first dialysate chamber 21 and the second dialysate chamber 22, respectively.

[0053] In addition, a dialysate pump 27 for conveying dialysate is provided at a position upstream of the branch portion in the dialysate recovery passage 25 , and recovery valves V5 and V6 are provided at the branch portions, respectively.

[0054] The upstream portion of the drainage passage 26 branches in two directions and is connected to the recovery chambers 21b and 22b of the first and second dialysate chambers 21 and 22, respectively, and the downstream portion is connected to a waste liquid tank (not shown). In addition, drainage valves V7 and V8 are provided at the branch portions, respectively.

[0055] In addition, the dialysate supply passage 24 is provided with a first dialysate filter F1 for removing harmful components of the dialysate and a first opening and closing valve V11 and a second opening and closing valve V12 provided at a predetermined interval, at a position downstream of the flow switch 28 .

[0056] The first dialysate filter F1 is divided into an upstream chamber and a downstream chamber by a semipermeable membrane. When the dialysate permeates from the upstream chamber through the semipermeable membrane to the downstream chamber, harmful components are removed.

[0057] A first bypass passage 29 for communicating the dialysate supply passage 24 with the dialysate recovery passage 25 is connected to the upstream chamber of the first dialysate filter F1 , and a third on-off valve V13 is provided in the first bypass passage 29 .

[0058] In addition, a second bypass passage 30 for connecting the dialysate supply passage 24 with the dialysate recovery passage 25 is connected between the first opening and closing valve V11 and the second opening and closing valve V12. In the second bypass passage 30, a second dialysate filter F2, the liquid replacement port 31 connected to the fluid replacement passage 6, and a fourth opening and closing valve V14 are sequentially arranged from the upstream side.

[0059] The second dialysate filter F2 is also divided into an upstream chamber and a downstream chamber by a semipermeable membrane in the same manner as the first dialysate filter F1. The upstream chamber is connected to a third bypass passage 32 via a second bypass passage 30. The third bypass passage 32 connects the dialysate supply passage 24 with the dialysate recovery passage 25. A fifth opening and closing valve V15 is provided in the third bypass passage 32.

[0060] During dialysis treatment, the connector 6a of the fluid replacement passage 6 is connected to the liquid replacement port 31 so that dialysate can be supplied to the fluid replacement passage 6. In addition, when preparing for dialysis treatment, the fluid replacement passage 6 is not connected so that the dialysate flows directly in the first bypass passage 29.

[0061] On the other hand, in the dialysate recovery passage 25, a sixth on-off valve V16, a pressure sensor 33 for measuring pressure, a dialysate pump 27 for conveying dialysate, and a degassing tank 34 for removing air from the dialysate are provided in order from the dialyzer 2 side.

[0062] The downstream end of the first bypass passage 29 is connected to a position adjacent to the upstream side of the pressure sensor 33, the downstream end of the second bypass passage 30 is connected to a position adjacent to the downstream side of the sixth on-off valve V16, and the downstream end of the third bypass passage 32 is connected between the first bypass passage 29 and the second bypass passage 30.

[0063] The degassing tank 34 is provided with a fourth bypass passage 35 that allows the dialysate recovery passage 25 and the drainage passage 26 to communicate with each other. The fourth bypass passage 35 is provided with a seventh on-off valve V17 .

[0064] Further, a fifth bypass passage 36 is provided downstream of the degassing tank 34 to connect the dialysate recovery passage 25 and the drainage passage 26 . A dewatering pump 37 is provided in the fifth bypass passage 36 to remove water during dialysis treatment.

[0065] In the above structure, just before instructing the control unit C to start the dialysis treatment, the puncture needles 11a and 12a of the blood circuit 3 are connected to the patient, and the control unit C operates the liquid supply pump of the liquid supply passage 23 and the dialysate pump 27 of the dialysate recovery passage 25, and controls the opening and closing of the various valves. In addition, the opening and closing unit 20 is opened manually to open the infusion passage 6. At this time, the dialysate pump 27 is operated by the control unit C at a predetermined flow rate required for the dialysis treatment, for example, a set flow rate of 100 ml / min, but the dewatering pump 37 and the infusion pump 19 are stopped.

[0066] When the supply pump and dialysate pump 27 of the supply passage 23 are in operation, and the supply chamber 21a of the dialysate chamber 21 is filled with dialysate and its volume reaches the maximum, the diaphragm D moves to the position of the dialysate pump 27. Figure 1 The left side of the dialysate chamber 21 is formed, so the volume of the recovery chamber 21b of the dialysate chamber 21 becomes zero. At this time, the volume of the supply chamber 22a of the other dialysate chamber 22 becomes zero, and the volume of the recovery chamber 22b of the dialysate chamber 22 becomes maximum ( Figure 1 status).

[0067] At this moment, the flow of dialysate in the dialysate circuit 4 stops, and therefore the flow switch 28 is turned off. When the flow switch 28 is turned off, the control unit C opens the supply valve V3 and the recovery valve V5 on the first dialysate chamber 21 side, and closes the supply valve V1 and the discharge valve V7. In this way, the dialysate pump 27 is used to transport the dialysate that has passed through the dialyzer 2 to the recovery chamber 21b. As a result, the diaphragm D is deformed and the volume of the supply chamber 21a is reduced. Therefore, the fresh dialysate contained in the supply chamber 21a is circulated in the dialysate supply passage 24 and supplied to the dialyzer 2.

[0068] When the dialysate flows through the dialysate circuit 4 in this manner, the flow switch 28 is turned on.

[0069] As described above, the control unit C opens the supply valve V3 and the recovery valve V5 on the first dialysate chamber 21 side and closes the supply valve V1 and the drain valve V7, and opens the supply valve V2 and the drain valve V8 and closes the supply valve V4 and the recovery valve V6 on the second dialysate chamber 22 side. As a result, fresh dialysate flows from the supply passage 23 into the supply chamber 22a, whereby the diaphragm D is deformed and the volume of the recovery chamber 22b is reduced, so that the used dialysate contained in the recovery chamber 22b is discharged to the outside through the drain passage 26.

[0070] When the recovery chamber 21 b of the first dialysate chamber 21 is filled with used dialysate and the volume of the supply chamber 21 a reaches zero, the flow of dialysate in the dialysate circuit 4 reaches zero, and therefore the flow switch 28 is turned off.

[0071] Since the dialysate delivery volume of the not-shown fluid supply pump provided in the fluid supply passage 23 is set to be larger than the dialysate delivery volume of the dialysate pump 27 of the dialysate recovery passage 25, before the recovery chamber 21b of the first dialysate chamber 21 is filled with used dialysate and the volume of the supply chamber 21a becomes zero, the supply chamber 22a of the second dialysate chamber 22 is filled with fresh dialysate, and thus the volume of the recovery chamber 22b becomes zero.

[0072] Therefore, when the flow switch 28 is in the disconnected state, the control component C switches the supply valves V1, V2, the supply valves V3, V4, the recovery valves V5, V6, and the drain valves V7, V8, so that fresh dialysate is supplied from the supply chamber 22a of the second dialysate chamber 22 to the dialyzer 2, and the used dialysate is recovered by the recovery chamber 22b. In addition, fresh dialysate is supplied from the supply passage 23 to the supply chamber 21a of the first dialysate chamber 21, and the used dialysate from the recovery chamber 21b is discharged to the outside through the drain passage 26.

[0073] In this way, whenever the flow switch 28 is disconnected, the control component C alternately opens and closes the supply valves V1, V2, the supply valves V3, V4, the recovery valves V5, V6, and the drain valves V7, V8, thereby continuously supplying fresh dialysate from the first dialysate chamber 21 and the second dialysate chamber 22 to the dialyzer 2 via the dialysate supply passage 24, and recovering the used dialysate that has passed through the dialyzer 2 to the first dialysate chamber 21 and the second dialysate chamber 22 via the dialysate recovery passage 25, thereby maintaining the circulation of the dialysate.

[0074] (Start of dialysis treatment)

[0075] When the control unit C is instructed to start the dialysis treatment from the above-mentioned dialysis treatment preparation state, the control unit C waits for either the supply chamber 21a or 22a to be filled with the dialysate and then starts the dialysis treatment.

[0076] During the dialysis treatment, the control unit C starts the operation of the water removal pump 37, and discharges the used dialysate from the dialysate circuit 4 to the external drainage passage 26 at a predetermined flow rate. The discharge amount by the water removal pump 37 is the amount of water including metabolites discharged from the blood to the outside through the dialyzer 2, that is, the water removal amount.

[0077] (Blockage Detection Operation of Fluid Infusion Path 6)

[0078] During the above-mentioned dialysis treatment, when a fluid infusion instruction such as performing fluid infusion at a flow rate of 50 ml / min for 30 minutes is given to the control unit C, the control unit C first detects whether there is blockage in the fluid infusion passage 6. For example, it detects whether the opening and closing member 20 such as a forceps, a clamp, or a Robert clamp that closes the fluid infusion passage 6 is forgotten to be removed or operated, so that the fluid infusion passage 6 remains in a closed state.

[0079] (First action: measurement of total amount discharge time)

[0080] The control component C measures the time from the moment the flow switch 28 is turned on to the moment the flow switch 28 is turned off at an appropriate timing, that is, the total amount of dialysate discharge time until the total amount of dialysate filled in the supply chamber 21a or the supply chamber 22a is discharged to the recovery chamber 21b or 22b side, and stores it.

[0081] At this time, for example, if the supply chamber 21a is filled and the flow switch 28 is turned off, the control component C is as follows. Figure 2 As shown in FIG. 1 , the supply valve V3, the recovery valve V5, and the on-off valve V15 are opened, and the on-off valves V12, V14, and V16 are closed, so that the total amount of dialysate in the supply chamber 21a is transported to the recovery chamber 21b via the second bypass passage 30 and the third bypass passage 32 instead of via the dialyzer 2. In addition, at this time, the control unit C stops the operation of the water removal pump 37.

[0082] Thus, when the dialysate in the supply chamber 21a starts to be delivered at a delivery rate of 100 ml / min by the dialysate pump 27, since the flow switch 28 is turned on, the control unit C measures the total amount discharge time from this moment to the moment when the dialysate in the supply chamber 21a disappears and the flow switch 28 is turned off. For example, when the measured total amount discharge time is one minute, it is stored as the total amount discharge time.

[0083] (Calibration Operation of Dialysate Pump 27)

[0084] In addition, when the maximum volume of the supply chamber 21a is 100ml, if the total amount discharge time is one minute, the actual flow rate of the dialysate pump 27 can be calculated to be 100ml / min. Since this value is consistent with the set flow rate of the dialysate pump 27 based on the control unit C, it can be determined that the dialysate pump 27 is operating at the correct set flow rate. In addition, since the volumes of the two supply chambers 21a and 22a are manufactured to be substantially the same in advance, it is sufficient to measure the discharge time when the dialysate is supplied from the supply chamber side of either side. However, since the volumes of the dialysate chambers 21 and 22 may be different from the designed volumes due to manufacturing errors, the accurate volumes of each are measured and input to the control unit C, and the control unit C is used to manage which supply chamber is used.

[0085] At this time, if the total discharge time is 61 seconds, the actual flow rate of the dialysate pump 27 is calculated to be 98.4 ml / min, so it can be determined that there is an error between the actual flow rate and the set flow rate. At this time, the control unit C adjusts the rotation speed, voltage, etc. of the dialysate pump 27 to make corrections so that the actual flow rate of the dialysate becomes 100 ml / min, which is the set flow rate.

[0086] On the contrary, if the total discharge time is 59 seconds, the actual flow rate of the dialysate pump 27 becomes 101.7 ml / min. Therefore, in this case, the control unit C also performs correction so that the actual flow rate of the dialysate matches the set flow rate.

[0087] As described above, in the present embodiment, the flow rate of the dialysate pump 27 is corrected based on the measured total discharge time. Therefore, in the total discharge time described below, one minute is used as the corrected discharge time.

[0088] In the above embodiment, the first action and the calibration of the dialysate pump 27 are executed immediately after the fluid infusion instruction is given to the control unit C. However, depending on the hemodialysis apparatus, the first action and the calibration of the dialysate pump 27 may be executed during the dialysis treatment.

[0089] That is, depending on the type of hemodialysis device, there is a hemodialysis device as follows: during dialysis treatment, the above-mentioned first action and the correction operation of the dialysate pump 27 (feedback control of the dialysate pump 27) are performed each time the total amount of dialysate is transported from the supply chamber 21a or 22a to the recovery chamber 21b or 22b.

[0090] In this case, the execution of the above-mentioned first action and the calibration operation of the dialysate pump 27 just after the fluid infusion instruction is given is omitted, and the discharge operation based on the fluid infusion pump 19 described below can be immediately executed by utilizing the first action and the calibration operation of the dialysate pump 27 that are executed last during the dialysis treatment.

[0091] (Discharge by the fluid infusion pump 19)

[0092] After the first operation is completed, the control unit C continues to wait for the supply chamber 21a or 22a to be filled with the dialysate. Then, for example, when the supply chamber 21a is filled with the dialysate and the dialysate starts to be supplied from the supply chamber 21a to the dialysate supply passage 24, Figure 3 As shown, the on-off valves V12 and V15 that have been opened so far are closed, and the operation of the fluid replacement pump 19 is started at a flow rate of 50 ml / min as a set flow rate based on the fluid replacement instruction condition.

[0093] When the above-mentioned infusion pump 19 is operated, the dialysate in the supply chamber 21a is supplied from the dialysate supply passage 24 to the blood circuit 3 via the infusion passage 6, thereby generating a flow in the flow switch 28. Since the flow switch 28 is turned on by a flow rate of more than the minimum operating flow rate flowing through the flow switch 28, if the minimum operating flow rate of the flow switch 28 is less than the above-mentioned 50 ml / min, the flow switch 28 is turned on by a flow rate of 50 ml / min, which is the instruction condition for the above-mentioned infusion. In this case, whether the infusion passage 6 is blocked can be determined based on whether the flow switch 28 is turned on.

[0094] However, when the minimum operating flow rate of the flow switch 28 is 50 ml / min or more, the flow switch 28 will not be turned on even if the above-mentioned fluid infusion pump 19 is operated to make the dialysate flow through the flow switch 28. Alternatively, when the minimum operating flow rate of the flow switch 28 is 50 ml / min or less but the command flow rate based on the fluid infusion command is set to be less than the minimum operating flow rate, the flow switch 28 will not be turned on.

[0095] Taking such a situation into consideration, in the present embodiment, as described below, the presence or absence of blockage in the fluid replacement passage 6 can be reliably detected.

[0096] (Second Action)

[0097] That is, when the control unit C is given a fluid infusion instruction as described above, first, the fluid infusion pump 19 is operated at a predetermined set flow rate for a predetermined time in a state where the supply chamber 21a is filled with dialysate, thereby executing a second action of discharging a portion of the dialysate filled in the supply chamber 21a into the blood circuit 3 via the fluid infusion passage 6.

[0098] More specifically, for example, by operating the infusion pump 19 at a set flow rate of 50 ml / min for one minute, an assumed amount of 50 ml of dialysate is discharged from the supply chamber 21a. Thus, the assumed amount of residual dialysate remaining in the supply chamber 21a becomes half of 50 ml.

[0099] At this time, when the volume in the supply chamber 21a actually decreases by 50 ml, the volume in the recovery chamber 21b increases by 50 ml. Since the dialyzer 2 becomes negative pressure when the volume in the recovery chamber 21b increases, 50 ml of water containing metabolites is filtered out from the blood.

[0100] The term “assuming” is used because if the fluid replacement passage 6 is completely blocked by the opening and closing member 20 , the actual discharge amount becomes zero, and the dialysate is not necessarily discharged reliably.

[0101] In addition, it is preferable that the amount of dialysate discharged from the supply chamber 21a by the infusion pump 19 is approximately half of the amount of dialysate filled in the supply chamber. This is because, when the amount discharged from the supply chamber 21a by the infusion pump 19 is small, the difference between the remaining amount discharge time and the total amount discharge time becomes small, and when the discharge amount is large, the set flow rate of the infusion pump is generally set to be smaller than the set flow rate of the dialysate pump, so the time required for the blockage detection of the infusion passage becomes longer.

[0102] (Third operation: measurement of remaining amount discharge time)

[0103] After the above one minute, that is, after the above second action is completed, the control component C switches to Figure 2 The circuit shown in the figure performs the following third action: the dialysate pump 27 is used to discharge the residual dialysate remaining in the supply chamber 21a to the recovery chamber 21b until the residual dialysate remaining in the supply chamber 21a disappears, and the residual discharge time is measured.

[0104] That is, after the above one minute, the control component C closes the on-off valve V16 and opens the on-off valve V15 to transport the remaining dialysate in the supply chamber 21a to the recovery chamber 21b. At this time, since the residual dialysate in the supply chamber 21a is transported at a transport volume of 100 ml / min by the dialysate pump 27, the flow switch 28 is reliably turned on. In addition, the control component C measures the remaining discharge time from this moment to the moment when the dialysate volume in the supply chamber 21a becomes zero and the flow switch 28 becomes disconnected.

[0105] At this time, when the residual discharge time is detected to be one minute, the residual discharge time is consistent with the total discharge time in the first action. Therefore, in this case, although 50 ml of dialysate should have been discharged from the supply chamber 21a through the second operation, in fact, the dialysate is not discharged at all.

[0106] On the other hand, when the residual discharge time is detected to be 30 seconds, since the set flow rate of the dialysate pump 27 is 100 ml / min, the actual residual dialysate amount remaining in the supply chamber 21a can be calculated to be 50 ml. If the infusion passage 6 is not blocked when the infusion pump 19 is operated for one minute, the assumed residual dialysate in the supply chamber 21a should be 50 ml. Therefore, in this case, it can be determined that the infusion passage 6 is not blocked.

[0107] (Fourth Operation: Operation of Determining Whether There is Blockage in the Fluid Infusion Path)

[0108] As described above, the control unit C compares the total amount discharge time measured in the first operation with the remaining amount discharge time in the third operation, and determines that the fluid replacement passage 6 is clogged when the difference between the two is within an allowable error range.

[0109] When the control unit C determines that the fluid replacement path 6 is blocked by the fourth operation, it warns of this fact by display or sound, and maintains the hemodialysis apparatus 1 in the state immediately before the instruction to start the dialysis treatment.

[0110] In addition, it is assumed that the above-mentioned liquid replenishment passage 6 is not completely opened. For example, when the remaining discharge time is detected to be 45 seconds, it becomes an incomplete opening state between complete blockage and complete opening. Whether a certain degree of incomplete opening is judged as "open" or "blockage" can be set in consideration of various situations, but if the case where the remaining discharge time is detected to be 45 seconds is included in the case of "opening", the case where the remaining discharge time is detected to be 45 seconds is included in the above-mentioned allowable error range.

[0111] That is, the above-mentioned allowable error range includes the error between the actual flow rate when the dialysate pump 27 is operated at the set flow rate without performing the calibration operation, the error between the actual flow rate when the infusion pump 19 is operated at the set flow rate, and also includes the situation where the infusion passage 6 is not completely opened but can be judged to be roughly opened.

[0112] Even when it is determined that the fluid replenishment passage 6 is clogged, when the opening and closing member 20 is opened manually and a fluid replenishment command is given to the control member C again, the above operation is repeated again to determine whether the fluid replenishment passage 6 is clogged.

[0113] (Calibration operation of the fluid replenishment pump 19)

[0114] When it is determined that the fluid replacement passage 6 is not blocked, the control means C performs the flow rate correction operation of the fluid replacement pump 19 using the remaining amount discharge time when it is not blocked.

[0115] That is, in the correction action of the fluid infusion pump 19, the actual flow rate of the fluid infusion pump 19 is calculated based on the set flow rate of the dialysate pump 27 in the above-mentioned third action and the residual discharge time. When there is an error between the set flow rate and the actual flow rate of the fluid infusion pump 19, the set flow rate of the fluid infusion pump 19 is corrected so that the error becomes zero.

[0116] More specifically, when the set flow rate of the dialysate pump 27 in the third operation is 100 ml / min and the residual discharge time is 30 seconds, the actual residual dialysate amount remaining in the supply chamber 21a can be calculated to be 50 ml, and therefore, the discharge amount by the infusion pump 19 in the second operation can be calculated to be 50 ml. In this case, since the infusion pump 19 in the second operation operates at the set flow rate of 50 ml / min for one minute, the set flow rate of the dialysate pump 27 is accurately operated at 50 ml / min, and no correction is required.

[0117] In contrast, when the set flow rate of the dialysate pump 27 in the above-mentioned third action is 100 ml / min and if the residual discharge time is detected to be 31 seconds, the actual residual dialysate amount remaining in the supply chamber 21a can be calculated to be 51.7 ml. Therefore, the discharge amount based on the infusion pump 19 in the above-mentioned second action is 48.3 ml, and the actual flow rate of the infusion pump 19 can be calculated to be 48.3 ml / min.

[0118] In this case, since there is an error between the set flow rate of 50 ml / min of the infusion pump 19 and the actual flow rate of 48.3 ml / min, the control component C corrects the rotation speed, voltage, etc. of the infusion pump 19 to make the actual flow rate consistent with the set flow rate.

[0119] Even when it is detected that the discharge time of the dialysate pump 27 in the second operation is shorter than 30 seconds, the control unit C corrects the rotation speed, voltage, etc. of the infusion pump 19 so that the actual flow rate matches the set flow rate.

[0120] After the calibration operation of the fluid replenishment pump 19 is completed as described above, the control unit C actually executes the above-mentioned fluid replenishment instruction, that is, an instruction to perform fluid replenishment at a flow rate of 50 ml / min for 30 minutes.

[0121] At this time, the hemodialysis apparatus 1 returns to the state of performing the above-mentioned dialysis treatment, and continues the operation of the calibrated fluid infusion pump 19 to perform fluid infusion for 30 minutes.

[0122] Then, after the predetermined time of water replenishment is completed, the operation of the fluid replenishment pump 19 is stopped, and the normal dialysis treatment is resumed.

[0123] In the above-mentioned embodiment, the terms "the volume in the supply chamber 21a becomes maximum", "the volume in the supply chamber 21a becomes zero", or "the dialysate in the supply chamber 21a disappears" are terms that include a certain degree of error in the amount of dialysate. This is because, as described above, the flow switch 28 is turned on or off depending on whether a flow rate of at least the minimum operating flow rate flows through the flow switch 28, and is not turned on or off depending on whether the flow rate becomes completely zero.

[0124] In addition, in the above embodiment, the flow rate of the dialysate pump 27 is corrected based on the measured total amount discharge time, but it is also possible that the flow rate of the dialysate pump 27 is not necessarily corrected. That is, in the above embodiment, the total amount discharge time of the dialysate pump 27 before correction, such as 61 seconds and 59 seconds, can be directly adopted as the total amount discharge time, and the total amount discharge time can be compared with the remaining amount discharge time of the third operation to determine whether the infusion passage 6 is blocked.

[0125] Furthermore, even if the flow rate of the dialysate pump 27 is not corrected, the actual flow rate of the dialysate pump 27 can be calculated as 98.4 ml / min or 101.7 ml / min based on the above-mentioned total discharge time. Therefore, during the correction operation of the infusion pump 19, the flow rate of the infusion pump 19 can be accurately corrected by using the above-mentioned actual flow rate as the set flow rate of the dialysate pump 27.

[0126] In addition, in the above-mentioned embodiment, the flow rate of the fluid infusion pump 19 is corrected when the fluid infusion instruction is given, but the flow rate of the fluid infusion pump 19 may be corrected multiple times at appropriate timing. The fluid infusion path 6 must be replaced every time dialysis treatment is performed, but since the flexibility of the tube constituting the fluid infusion path 6 changes all the time, it is preferable to replace it multiple times during the fluid infusion process.

[0127] Alternatively, when calibration of the dialysate pump 27 and calibration of the infusion pump 19 are omitted, the total amount discharge time may be obtained by calculation based on the maximum capacity of the supply chambers 21a and 22a and the set flow rate of the dialysate pump 27 .

[0128] Furthermore, in the above-described embodiment, the flow switch 28 is used for measuring time, but the present invention is not limited to the flow switch 28, and any measuring means may be used as long as it can measure time.

[0129] In addition, in the above-mentioned embodiment, the dialysate chambers 21 and 22 are divided into two chambers, namely, the supply chambers 21a and 22a and the recovery chambers 21b and 22b, by the diaphragm D, but the present invention is not limited thereto. As shown in FIG. 9 of Patent Document 1, the present invention can also be applied to a hemodialysis device in which the interior of the dialysate chamber is divided into three chambers by two diaphragms D and a variable volume chamber is formed between the supply chamber and the recovery chamber.

Claims

1. A device for detecting a blockage of a fluid infusion passage in a hemodialysis device, the hemodialysis device comprising: a dialysate chamber, the dialysate chamber being divided into a supply chamber and a recovery chamber by a diaphragm; a dialysate supply passage, the dialysate supply passage connecting the supply chamber with a dialyzer; a dialysate recovery passage, the dialysate recovery passage connecting the dialyzer with the recovery chamber; a dialysate pump, the dialysate pump being disposed in the dialysate recovery passage; a blood circuit, the blood circuit being connected to the dialyzer; a fluid infusion passage, the fluid infusion passage being connected to the dialysate supply passage and the blood circuit; a fluid infusion pump, the fluid infusion pump being disposed in the fluid infusion passage; and a control component, the control component controlling the dialysate pump and the fluid infusion pump, characterized in that The control component performs the first action, the second action and the third action, and also performs the fourth action. In the first operation, the dialysate pump is operated at a predetermined set flow rate, and a total discharge time is acquired, which is a time until the dialysate filling the supply chamber disappears. In the second operation, the liquid infusion pump is operated at a predetermined flow rate for a predetermined time, thereby discharging a portion of the dialysate filling the supply chamber. In the third operation, the dialysate pump is operated at a predetermined set flow rate, and a residual discharge time is obtained, which is the time until the residual dialysate remaining in the supply chamber disappears after the second operation is completed. In the fourth operation, when the difference between the remaining amount discharge time and the total amount discharge time is within a required tolerance range, it is determined that the fluid replacement passage is clogged.

2. The clogging detection device for a fluid replacement passage in a hemodialysis device according to claim 1, characterized in that: The total amount discharge time in the first operation is acquired by actually operating the dialysate pump at a predetermined set flow rate and measuring the time until the dialysate filling the supply chamber disappears.

3. The clogging detection device for a fluid replacement passage in a hemodialysis device according to claim 1 or 2, characterized in that: The amount of dialysate discharged from the supply chamber by the fluid replacement pump is approximately half of the amount of dialysate filled in the supply chamber.

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