JP3928888B2 - Blood purification equipment - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a blood purification apparatus, particularly a continuous slow blood filtration method (hereinafter simply referred to as “CHF”) in an emergency / intensive treatment area such as renal diseases having severe circulatory system complications and multiple organ failure. The present invention relates to a device suitable for continuous hemodiafiltration (hereinafter simply referred to as “CHDF”).
[0002]
[Prior art]
In recent years, CHF or CHDF blood purification methods have been effective in the treatment of renal diseases and circulatory organ complications. CHF continuously and slowly applies blood to a blood purifier containing a semipermeable membrane, discharges the filtered solution through the membrane, and replenishes the body with a replacement solution. In addition, in order to improve the small molecular weight removal capability of CHF, CHDF is designed to obtain a dialysis effect by flowing a dialysate to the filtrate side in addition to CHF. These treatments include a blood pump that circulates blood to the blood purifier, a filtrate pump that drains filtrate from the blood purifier, a replacement fluid pump that replenishes the patient with replacement fluid, and a dialysate that supplies dialysate to the blood purifier The flow rate of the pump (only in the case of CHDF) is set, and the amount of change in body fluid (dialyzed fluid amount + replacement fluid amount−filtrate amount) is controlled and enforced.
[0003]
[Problems to be solved by the invention]
Usually, a so-called tubing pump is used for discharging the filtrate and injecting the replacement liquid, in order to maintain sterility, and feeding the liquid while closing the tube. However, it is difficult to keep the flow rate of the tubing pump constant because the physical properties of the tube change due to fatigue and temperature, and an error of 5 to 10% cannot be overcome with respect to the change of conditions within the normal use range. In order to strictly manage the amount of change in body fluid, it is necessary to frequently measure and adjust the flow rate of each pump. This operation is complicated, and there is a problem that the patient is constantly monitored from the viewpoint of erroneous operation.
In contrast to this, as shown in FIG. 2, a method of automatically adjusting each pump while measuring the injection amount of the replacement liquid and the discharge amount of the filtrate with a weight meter has been devised. When discarding the filtrate, the treatment must be stopped once and a complicated procedure is required. In some cases, replenishment or disposal operations are mistakenly performed during treatment, resulting in a large error. In addition, in order to reduce the frequency of replenishment and disposal operations, if the measuring range of the weigh scale is widened so that a large amount of replacement liquid or filtrate can be suspended at one time, measurement accuracy deteriorates and disturbance due to vibrations, etc. Will increase and introduce errors.
The present invention has been made to solve the above-described problems of the prior art, and automatically measures the flow rate of filtrate, dialysate, and replacement fluid of a blood purification device when treating kidney disease, multiple organ failure, and the like. It is an object of the present invention to provide an apparatus capable of facilitating the operation and ensuring patient safety by controlling it.
[0004]
[Means for Solving the Problems]
Blood circulation paths (17) and (18) for introducing the patient's blood into a blood purifier (16) containing a semipermeable membrane and returning it to the patient again, and a replacement fluid for supplying a replacement fluid to the patient via the blood circulation path Dialyze from the passages (22), (24) and the filtrate discharge passages (20), (23) for discharging the blood filtrate from the blood purifier, or to the blood circulation path, the replacement fluid path, and the blood purifier. A blood filtration system comprising a dialysate supply path (19) (21) for supplying a liquid and a filtrate / dialysate discharge path (20) (23) for discharging the blood filtrate and used dialysate from the blood purifier; In the blood purification apparatus that performs hemodialysis or hemodiafiltration, the fluid replacement paths (22) and (24) are connected to the liquid supply pump (7) and the measuring bag (13) from the side close to the blood circulation paths (17) and (18). ) And weight scale (3), valve (10), and replacement liquid reservoir (15). The filtrate discharge path or the filtrate / dialysate discharge path (20) (23) is provided in this order from the side close to the blood circulation path (17) (18), and the liquid feeding pump (6) and the measuring bag ( 12) and the weigh scale (2) and the valve (9) are provided in this order, and the dialysate supply passages (19) and (21) are fed from the side close to the blood circulation passages (17) and (18). A pump (5), a measuring bag (11) and a weighing scale (1), a valve (8), and a dialysate reservoir (14) are provided in this order. Each valve is connected to a control device (25) so as to be individually controllable. The control device (25) constantly monitors data of each weighing scale, and in the replacement fluid paths (22) and (24), the valve (10) Open the valve and separate the liquid from the replacement liquid reservoir (15) into the weighing bag (13). The initial state of closing (10) and the operation of controlling the rotation speed of the liquid feeding pump (7) so that the actual flow rate and the set flow rate become equal according to the weight reduction per unit time of the measuring bag are repeated, and dialysis In the liquid supply passages (19) and (21), the valve (8) is opened, and after the liquid is separated from the dialysate reservoir (14) into the measuring bag (11), the valve (8) is closed, Repeat the operation to control the rotation speed of the liquid feed pump (5) so that the actual flow rate and the set flow rate become equal according to the weight reduction per unit time of the measurement bag, and the filtrate discharge path or filtrate / dialysate discharge In the passages (20) and (23), the liquid feed pump (6) is set so that the actual flow rate and the set flow rate become equal according to the weight increase per unit time of the measuring bag (12) with the valve (9) closed. Operation to control the rotation speed of Blood purification, characterized in that repeated operations and to discard the accumulated liquid in the weighing bag by opening the valve (9) (12), the above flow rate control to reduce the water removal error performed individually in each liquid path apparatus.
[0005]
【Example】
Next, an embodiment of the apparatus of the present invention will be described with reference to the drawings.
FIG. 1 is a flowchart showing the configuration when CHDF is implemented in the apparatus of the present invention. The blood taken out from the patient by the blood pump 4 passes through the blood collection line 17, is introduced into the blood purifier 16 containing the filtration membrane M, and forms a blood circulation path so as to return to the patient from the blood return line 18 again. . Further, a replacement fluid line 24 is connected to the blood return line 18 so that the replacement fluid can be injected into the patient by the replacement fluid pump 7. On the other hand, the blood component filtered by the filtration membrane M of the blood purifier 16 is discharged by the filtrate pump 6 provided in the filtrate line 20. Further, the dialysate pump 5 supplies the dialysate from the dialysate supply line 19 to the blood purifier 16, and the filtrate is discharged together with the filtrate by the filtrate pump 6.
Here, assuming that the flow rate of the replacement fluid pump is Q _C (ml / h), the flow rate of the filtrate pump is Q _F (ml / h), and the flow rate of the dialysate pump is Q _D (ml / h), The change dV (ml / h) of dV = Q _D + Q _C −Q _F
It is represented by Usually, patients often have excessive hydration due to decreased urine volume due to decreased renal function, and dV is set to a negative value to remove water (hereinafter simply referred to as “water removal”). The amount of change in total body fluid during treatment is called the amount of water removal and is managed. The water removal amount must be managed accurately, but since the treatment time is long, slight errors in Q _D , Q _C , and Q _F cause a large water removal amount error. For example, when treatment is performed for 20 hours with Q _D = 500 ml / h, Q _C = 400 ml / h, Q _F = 1,000 ml / h, the water removal amount is 2,000 ml, but each pump is ± 5% If there is an error, the water removal error is (± 25 ± 20 ± 50) × 20 = ± 1,900 ml, and it has an error of about ± 100% for the target water removal amount. . Therefore, in the present invention device Q _D, Q _C, it is improved the precision of dewatering amount by by actually measuring the Q _F feedback control of each pump.
[0006]
First, control of the dialysate flow rate Q _D will be described. The dialysate stored in the dialysate reservoir 14 is sent to the measuring bag 11 by a drop by opening the valve 8 provided in the dialysate replenishment line 21. The weight scale 1 measures the weight of the weighing bag 11 and sends data to the control device 25.
The control device 25 detects that the weight of the measuring bag 11 has exceeded a certain value, closes the valve 8, stops the flow of dialysate to the measuring bag 11, and sets this state as the initial state. The dialysate pump 5 starts to send dialysate to the blood purifier 16 by driving the motor at a rotation speed corresponding to a preset flow rate. The control device 25 constantly monitors the data of the weigh scale 1 and calculates the actual flow rate of the dialysate from the change in weight per unit time. If there is a difference between the actual flow rate and the set flow rate, the rotational speed of the motor is determined. It adjusts automatically and controls the set flow rate to be equal to the actual flow rate. When the remaining dialysate in the measuring bag 11 is reduced and the weight falls below a certain value, the control device 25 opens the valve 8 again and fills the measuring bag 11 with the dialysate and returns to the initial state. While the valve 8 is open, the dialysate pump 5 maintains the previous rotational speed, but when it returns to the initial state, the control starts again. By repeating the above, the dialysate flow rate can be maintained at the set flow rate with high accuracy. While the valve 8 is open, the dialysate pump is not controlled, but it is much shorter than the controlled time, and the flow rate characteristic of the pump does not change abruptly.
[0007]
The replacement fluid flow rate Q _C is controlled in the same manner as the dialysate flow rate Q _D. That is, the replacement liquid stored in the replacement liquid reservoir 15 is sent to the measuring bag 13 by a drop by opening the valve 10 provided in the replacement liquid replenishment line 22. The weighing scale 3 measures the weight of the weighing bag 13 and sends data to the control device 25. The control device 25 detects that the weight of the measuring bag 13 has become a certain value or more, closes the valve 10, stops the flow of the replacement liquid to the measuring bag 13, and sets this state as the initial state. The replacement fluid pump 7 starts injecting the replacement fluid into the patient via the replacement fluid line 24 and the blood return line 18 by driving the motor at a rotation speed corresponding to a preset flow rate. The control device 25 constantly monitors the data of the weigh scale 3 and calculates the actual flow rate of the replacement liquid from the change in weight per unit time. If there is a difference between the actual flow rate and the set flow rate, the rotational speed of the motor is determined. It adjusts automatically and controls the set flow rate to be equal to the actual flow rate. When the remaining amount of the replacement liquid in the measurement bag 13 eventually decreases and the weight falls below a certain value, the control device 25 opens the valve 10 again, fills the measurement bag 13 with the replacement liquid, and returns to the initial state. While the valve 10 is open, the replacement fluid pump 7 maintains the previous rotational speed, but when it returns to the initial state, the control starts again.
[0008]
The filtrate flow rate Q _F is controlled by the control device 25 as follows. The filtrate pump 6 starts to send the filtrate to the measuring bag 12 by driving the motor at a rotation speed corresponding to a preset flow rate. At this time, the valve 9 is closed, and the change in the weight of the measuring bag 12 detected by the weigh scale 2 becomes the actual flow rate of the filtrate. The rotational speed of the motor is controlled so that this actual flow rate becomes equal to the set flow rate. Eventually, when the measuring bag 12 is full and the weight exceeds a certain value, the valve 9 is opened and the filtrate in the measuring bag 12 is discarded from the waste liquid line 23. At this time, the filtrate pump 6 maintains the previous rotational speed, but when the weight of the measuring bag 12 falls below a certain value and the disposal of the filtrate is finished, the valve 9 is closed and the same rotational speed control is started again.
As described above, each pump can maintain a high flow rate accuracy, and as a result, the error of the water removal amount can be managed with a small amount.
In addition, according to the present embodiment, replacement of the replacement fluid and dialysate and discarding of the filtrate do not directly affect the weight measurement, and can be performed arbitrarily without stopping the treatment. In addition, the measurement range of each weighing scale may be in the range of the capacity of each weighing bag, and the measurement accuracy can be kept high and disturbance can be reduced.
[0009]
【The invention's effect】
As described above, according to the present invention, the dialysate flow rate, the replacement fluid flow rate, and the filtrate flow rate can be automatically controlled with high accuracy, and the patient's body fluid can be safely and without requiring frequent measurement and adjustment work by the staff. Treatment can be performed while controlling the amount.
[Brief description of the drawings]
FIG. 1 is a flowchart showing the configuration of one embodiment of a device of the present invention.
FIG. 2 is a flowchart showing a configuration of an example of a conventional apparatus.
[Explanation of symbols]
1, 2, 3 Weigh scale 4 Blood pump 5 Dialysate pump 6 Filtrate pump 7 Replacement fluid pump 8, 9, 10 Valve 11, 12, 13 Metering bag 14 Dialysate reservoir 15 Replacement fluid reservoir 16 Blood purifier 17 Blood collection Line 18 Blood return line 19 Dialysate supply line 20 Filtrate line 21 Dialysate replenishment line 22 Replacement liquid replenishment line 23 Waste liquid line 24 Supplement liquid line 25 Controller 26 Filtrate reservoir

Claims (1)

Blood circulation paths (17) and (18) for introducing the patient's blood into a blood purifier (16) containing a semipermeable membrane and returning it to the patient again, and a replacement fluid for supplying a replacement fluid to the patient via the blood circulation path Dialyze from the passages (22), (24) and the filtrate discharge passages (20), (23) for discharging the blood filtrate from the blood purifier, or to the blood circulation path, the replacement fluid path, and the blood purifier. A blood filtration system comprising a dialysate supply path (19) (21) for supplying a liquid and a filtrate / dialysate discharge path (20) (23) for discharging the blood filtrate and used dialysate from the blood purifier; the blood purification apparatus for performing hemodialysis or hemodiafiltration, the replacement fluid channel (22) (24), from the side close to the blood circuit (17) (18), and liquid feed pump (7), the weighing bag (13 ) And weight scale (3), valve (10), and replacement liquid reservoir (15). The filtrate discharge path or the filtrate / dialysate discharge path (20) (23) is provided in this order from the side close to the blood circulation path (17) (18), and the liquid feeding pump (6) and the measuring bag ( 12) and the weigh scale (2) and the valve (9) are provided in this order, and the dialysate supply passages (19) and (21) are fed from the side close to the blood circulation passages (17) and (18). A pump (5), a measuring bag (11) and a weighing scale (1), a valve (8), and a dialysate reservoir (14) are provided in this order. Each valve is connected to a control device (25) so as to be individually controllable. The control device (25) constantly monitors data of each weighing scale, and in the replacement fluid paths (22) and (24), the valve (10) Open the valve and separate the liquid from the replacement liquid reservoir (15) into the weighing bag (13). The initial state of closing (10) and the operation of controlling the rotation speed of the liquid feeding pump (7) so that the actual flow rate and the set flow rate become equal according to the weight reduction per unit time of the measuring bag are repeated, and dialysis In the liquid supply passages (19) and (21), the valve (8) is opened, and after the liquid is separated from the dialysate reservoir (14) into the measuring bag (11), the valve (8) is closed, Repeat the operation to control the rotation speed of the liquid feed pump (5) so that the actual flow rate and the set flow rate become equal according to the weight reduction per unit time of the measurement bag, and the filtrate discharge path or filtrate / dialysate discharge In the passages (20) and (23), the liquid feed pump (6) is set so that the actual flow rate and the set flow rate become equal according to the weight increase per unit time of the measuring bag (12) with the valve (9) closed. Operation to control the rotation speed of The operation of opening the valve (9) and discarding the liquid accumulated in the measuring bag (12) is repeated, and the above flow rate control is individually performed in each liquid path to reduce the water removal error. apparatus.

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