JP4158334B2 - Blood purification equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a blood purification apparatus, and more particularly to a blood purification apparatus that can automatically perform blood purification adapted to each patient and automatically terminate blood purification.
[0002]
[Prior art]
Conventionally, treatment by blood purification such as hemodialysis, hemofiltration, and hemodiafiltration has been performed to treat patients whose renal function is impaired, for example, patients whose function of removing waste products in the blood is impaired due to renal failure. It has been broken. In this blood purification treatment, various work steps by medical personnel such as priming, replacement fluid, and recovery of residual blood are required. Therefore, when blood purification is performed by a large number of people at one time, the work efficiency is poor, and automation of work processes is being promoted for the purpose of rapid blood purification treatment.
[0003]
In blood purification treatment, the water removal rate when removing excess water in the blood must be performed while maintaining an appropriate amount of blood circulating in the body (hereinafter simply referred to as blood volume) unique to each patient. During blood purification, the patient's bodily fluid moves into cells, intercellular spaces, blood vessels, and dialysate due to water removal. Here, the movement of bodily fluid from the intercellular space into the blood vessel is generally called refilling, and the movement from the blood vessel to the dialysate side is called water removal, but the water removal speed is reduced by sudden or excessive water removal. If the filling speed is exceeded, the blood volume decreases, which may cause a decrease in blood pressure or shock. On the other hand, if water removal is slow, it takes a long time for blood purification, and if water removal is not sufficient, there is a risk of causing hypertension, heart failure, and the like. Therefore, automation of water removal in the blood purification apparatus should be advanced in consideration of the above problems.
[0004]
As a blood purification apparatus in which water removal is automated, blood purification apparatuses that perform water removal while monitoring the blood state of a patient have been proposed (Japanese Patent Publication No. 4-22586, Japanese Patent Publication No. 4-22587, No. 6-83723). These blood purification devices determine the hematocrit value in the blood from the electrical resistivity of the blood, etc., reduce the water removal rate when the hematocrit value is larger than the set value, and again when the hematocrit value becomes smaller than the set value. The blood purification treatment is performed while appropriately controlling the blood volume. In addition, blood purification conditions are set for each area by dividing the hematocrit value or blood volume into multiple areas, and when the hematocrit value or blood volume shifts to a different area, the blood purification conditions are changed to the set blood purification conditions. A blood processing apparatus that performs this is also known (Japanese Patent Laid-Open No. 11-212275). According to this apparatus, it is possible to control the circulating blood volume more precisely.
However, according to the blood purification apparatus described above, blood purification that maintains an appropriate blood volume is automated, but it is not considered until the blood purification is automatically terminated.
[0005]
[Problems to be solved by the invention]
In view of the above circumstances, an object of the present invention is to provide a blood purification apparatus capable of automatically purifying blood while maintaining an appropriate blood volume, and further capable of automatically terminating blood purification.
[0006]
[Means for Solving the Problems]
As a result of diligent investigations to solve the above problems, the present inventors have increased the blood volume when the blood volume that tends to decrease as blood purification is performed reaches a predetermined value. By repeating the control function to terminate blood purification when the rate of increase in blood volume per unit time when the blood volume increases reaches a predetermined value, both blood purification and termination of blood purification are performed. The present inventors have found that the work process can be automated and have reached the present invention.
[0007]
That is, the present invention provides a blood purification unit, and a blood parameter measuring means, the blood parameters in terms of blood volume, the blood purification device comprising a control unit for controlling the blood purification unit based on the blood volume, blood An operation in which the control unit instructs the blood purification unit to change the blood purification condition so as to increase the blood volume when the blood volume that tends to decrease as purification is performed reaches a predetermined value; The control unit changes the blood purification conditions so that the blood volume is decreased when the blood volume increases and reaches the next predetermined value or when a predetermined time elapses due to a change in conditions. operations and to instruct again the blood purification unit, when the control unit to repeat a plurality of times, the rate of increase of blood volume per unit time in the blood volume increases life has reached the predetermined value decreases, wherein the control unit before the completion blood purification A blood purification apparatus characterized by having a function to instruct the blood purification unit.
[0008]
[Action]
According to the present invention, when the blood volume that tends to decrease as blood purification is performed reaches the predetermined value, the blood volume is increased, and this operation is repeated a plurality of times to obtain a unit volume per unit time when the blood volume is increased. When the rate of increase of the blood volume reaches a predetermined value, by incorporating a control function for terminating blood purification, blood purification can be performed automatically while maintaining an appropriate blood volume, and Blood purification can be automatically terminated.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the blood purification apparatus of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing an embodiment in the case where the blood purifier is a hemodialyzer or a hemodialysis filter in the blood purification apparatus of the present invention, and FIG. 2 is a blood purification apparatus in the blood purification apparatus of the present invention. It is a block diagram which shows one Example in case a device is a blood filter. FIG. 3 is a conceptual diagram showing the change over time of the operation of the blood purification apparatus of the present invention.
As shown in FIG. 1 or 2, the blood purification apparatus 1 of the present invention includes a blood purification unit 2, a measuring unit 6, and a control unit 7.
[0010]
The blood purification unit 2 of the present invention includes a blood purification device 3 for purifying blood and a blood circuit 4 connected to the blood purification device 3 in communication therewith.
The blood purifier 3 refers to a hollow fiber membrane type, specifically, a hollow fiber membrane hemodialyzer, a hollow fiber membrane hemodialyzer, a hollow fiber membrane hemodialyzer, and the like. The blood filter circulates blood inside the hollow fiber membrane, and moves unnecessary substances in the blood, such as urea and creatinine, and water to the outside of the hollow fiber membrane by filtration through the hollow fiber membrane (blood filtration) Is. The hemodialyzer and hemodialysis filter allow blood to flow inside the hollow fiber membrane and dialysate to flow outside the hollow fiber membrane so as to face each other, and unnecessary substances in the blood are passed through the hollow fiber membrane. They are moved into the dialysate by diffusion (hemodialysis) or the hemodialysis and hemofiltration are performed simultaneously (hemodiafiltration).
As the hollow fiber membrane material, synthetic resins such as polymethyl methacrylate, polyvinyl alcohol, polyacrylonitrile, ethylene-vinyl alcohol copolymer, cellulose acetate, polypropylene, polyethylene, polysulfone, and polyamide are used.
[0011]
The blood purifier 3 is provided with a blood inlet 31 and a blood outlet 32 communicating with the inside of the hollow fiber membrane. The blood inlet 31 is connected to an arterial line 41 for introducing the patient's blood flowing from the blood sampling port 44 into the blood purifier 3, and the blood outlet 32 is introduced into the blood purifier 3. A venous line 42 for returning the purified blood to the patient's body through the blood return port 45 is connected. The blood circuit 4 in the present invention is provided on the lines 41 and 42 such as the inner side of the hollow fiber membrane of the blood purifier 3, the artery side line 41, the vein side line 42, and a drip chamber (not shown) if necessary. This refers to a path through which blood or the like passes during blood purification. On the blood circuit 4, a replacement fluid part 46, a blood anticoagulant injection part, and the like may be provided.
As the arterial line 41 and the venous line 42, tubes made of synthetic resin or the like are used. Specifically, it is a polyvinyl chloride tube, a silicone rubber tube, or the like.
A blood pump 43 is provided on the blood circuit 4 for circulating the blood, dialysate, air, or the like in the circuit 4. The blood pump 43 may be provided in any part as long as it is in the blood circuit 4, but is preferably in the artery side line 41. As the blood pump 43, a roller type, a pulsation type, a centrifugal pump or the like is used.
[0012]
When the blood purifier 3 is a hemodialyzer or a hemodialysis filter, as shown in FIG. 1, a water removal pump 51, a dialysate supply line 52, and a dialysate are disposed outside the hollow fiber membrane of the blood purifier 3. The dialysate circuit 5 including the discharge line 53 is connected and used. On the other hand, if the blood purifier 3 is hemofilter, sequester one permeable析液inlet 33 and dialysate outlet 34, as shown in FIG. 2, the drain line 54 equipped with a ultrafiltration pump 51 to the other connection Used. In FIG. 1, the dialysate circuit 5 includes a dewatering pump 51, the dialysate supply line 52, and a dialysate discharge line 53, as well as components provided on the lines 52 and 53, for example, dialysate It includes means for removing harmful substances such as pyrogen substances contained therein (such as a filtration method using a hollow fiber membrane or an adsorption method using an adsorbent), a dialysate preparation device 55, and a dialysate temperature controller. In addition, an injection part 56 for injecting a sodium chloride aqueous solution or the like may be provided on the line 53 in order to change the concentration of the dialysate. The dialysate supply line 52 and the dialysate discharge line 53 are the same as the arterial line 41 and the venous side line 42, such as a tube made of polyvinyl chloride, a tube made of silicone rubber, a polypropylene tube, a polyethylene tube, etc. A hard tube is used.
[0013]
On the blood circuit 4 of the present invention, measuring means 6 for measuring blood parameters is provided. The measuring means 6 is not particularly limited as long as it can measure blood parameters and grasp the blood circulation state in the body by the measurement, but specifically, the light transmittance of blood, blood osmotic pressure, electrolytic mass, electricity It is a device that continuously measures blood parameters such as resistivity.
[0014]
The blood parameters measured by the measuring means 6 are sent to the control unit 7. The control unit 7 is a part that instructs and controls the blood purification unit 2 to perform blood purification under a predetermined condition. Specifically, (1) a known blood volume value (hereinafter referred to as a BV value). Various blood purification conditions, processing, operation, and the like (hereinafter referred to as blood purification conditions) are set based on (2) the blood parameter measured in the measuring means 6 is converted into a BV value, and the BV value The blood purification condition is selected on the basis of (3), and (3) the blood purification unit 2 is commanded and controlled for the selected blood purification condition.
[0015]
In the function (1) of the control unit 7, the blood purification conditions such as blood purification conditions, processing, and operations are operation conditions for blood purification, and are set in advance based on, for example, a known BV value. Dehydration rate, body circulation blood flow rate, fluid replacement rate, dialysate concentration, dialysate temperature, sodium chloride aqueous solution injection rate, etc. Therefore, a plurality of predetermined BV values are determined for each patient based on the known BV values of the patient's past dialysis records or the like previously recorded in the control unit 7, and blood purification conditions are determined based on the predetermined BV values. In addition to the water removal rate, various blood purification conditions such as the blood circulation rate in the body, the fluid replacement rate, the dialysate concentration, and the dialysate temperature are set in advance. The blood purification conditions that are arbitrarily set other than the water removal speed may be set such that only one of the conditions is selected or a plurality of conditions are selected.
[0016]
In the function (2) of the control unit 7, the blood parameters continuously measured by the measuring means 6 are converted into conversion formulas suitable for each blood parameter (Japanese Patent Publication No. 6-83723, Japanese Patent Application Laid-Open No. 11-212275). Is converted into a BV value. Based on the obtained BV value, the blood purification conditions set in advance as described above are selected. That is, the condition is such that the BV value, which tends to decrease as blood purification is performed, is increased.
[0017]
In the function (3) of the control unit 7, the command and control to the blood purification unit 2 are performed by transmitting the blood purification condition selected by the control unit 7 to the blood purification unit 2. The blood purification conditions are, for example, transmitted to the blood pump 43 of the blood purification unit 2 to control the blood circulation speed in the body, or to the water removal pump 51 to control the water removal speed, or infusion The dialysate concentration is controlled by being transmitted to the unit 56, and the rate of the replacement fluid is controlled by being transmitted to the replacement unit 46.
[0018]
Next, the case where the water removal speed is changed by controlling the water removal pump based on the measured BV value using the blood purification apparatus of the present invention will be described.
The curve in FIG. 3A shows the transition of the BV value of the patient that changes during the blood purification by driving / stopping the water removal pump 51. The vertical axis represents the BV value, and the horizontal axis represents the blood purification time. Represents. FIG. 3B shows the driving / stopping of the water removal pump 51 that affects the water removal speed, which is one of the blood purification conditions. The drive of the water removal pump 51 shown in FIG. 3B (displayed as ON in FIG. 3) does not always have to be a constant value, and may be changed with the transition of the BV value. Further, the stop of the water removal pump 51 (displayed as OFF in FIG. 3) does not indicate only the state of complete stop, but may be driven at a lower flow rate than that during driving. In addition to driving / stopping the dewatering pump, any one of the blood conditions such as blood flow rate, replacement fluid rate, dialysate concentration, dialysate temperature, and injection rate may be changed. Two or more conditions may be changed.
[0019]
When blood purification is started, the blood parameter in the blood flowing through the blood circuit 4 is measured by the measuring means 6, and the blood parameter is sent to the control unit 7 and converted into a BV value by the control unit 7. As shown in A of FIG. 3A, the patient's BV value tends to decrease as blood purification is performed. At this time, the water removal pump 51 is driven as shown in FIG. Here, the decreasing tendency includes a case where the BV value partially increases even if blood purification is performed at a constant speed depending on the patient's constitution.
That is, when blood purification is started, the blood that has flowed into the blood circuit 4 from the blood collection port 44 by the blood pump 43 is drained by the drive of the water removal pump 51 in the blood purification device 3, and then from the blood return port 45 to the body. Returned to Since the blood returned to the body is replenished with water by refilling, the BV value at the initial stage of blood purification does not change greatly as shown in A of FIG. Since the refilling speed decreases with the passage of time, the BV value gradually decreases.
[0020]
When the decreasing BV value reaches a predetermined value set in advance, that is, (1) in FIG. 3A, the control unit 7 changes the blood purification condition to the blood purification unit 2, that is, a water removal pump. Instruct to stop 51 or decrease speed. As a result, the water removal rate decreases, and the BV value increases due to refilling. When the BV value reaches the next predetermined value, that is, (2) in FIG. 3A, the control unit 7 instructs the blood purification unit 2 to change the blood purification condition again, that is, to drive the water removal pump 51. The BV value decreases. Next, when the BV value reaches (3) in FIG. 3A, the water removal pump 51 is stopped, when it reaches (4), the water removal pump 51 is driven, and when it reaches (5), the water removal pump 51 is turned off. The blood purification is performed while repeating the operation of driving and stopping the water removal pump 51 a plurality of times, such as driving the water removal pump 51 when stopping and reaching (6). The timing of changing the blood purification condition so as to decrease the BV value, that is, the timing of conversion to C, E, or G in FIG. 3 (a), instead of controlling with the predetermined BV value as described above, Alternatively, it may be controlled according to the time required for F.
In the above description, the water removal speed is changed by controlling the water removal pump 51 based on the BV value. In addition to the control of the water removal pump 51, the blood pump 43, the liquid replacement pump of the liquid replacement section 46, or the liquid injection section 56 The water removal speed may be changed by controlling the liquid injection pump. For example, at the time of A, C, E, and G in FIG. 3A, the liquid replacement pump of the liquid replacement unit 46 and the liquid injection pump of the liquid injection unit 56 are stopped, and both of the above are performed at the time of B, D, and F. Control such as driving the pump can be performed.
[0021]
In the BV value decreasing period as indicated by C, E and G in FIG. 3, the control unit 7 calculates the increase rate of the BV value per unit time in the BV value increasing period indicated by B, D and F. . The increase rate is obtained by, for example, calculating the difference between the minimum value and the maximum value of the BV value (ΔBV in the figure) from the minimum value to the maximum value in the curve of FIG. And divided by the time required for transition (Δt in the figure). The increase rate may be obtained based on the area surrounded by the X axis, the Y axis, and the curve in FIG.
As blood purification progresses, the intracellular water decreases and the refilling speed also decreases, so the increase rate of the BV value gradually decreases. Until the increase rate of the BV value reaches a predetermined value, the blood purification is repeated until the BV value decreases and increases. When the increase rate reaches the predetermined value, the control unit 7 sends blood to the blood purification unit 2. The end of purification is instructed, and the driving devices such as a blood pump and a dewatering pump are stopped.
[0022]
【The invention's effect】
By using the blood purification apparatus of the present invention, blood purification can be performed automatically while maintaining an appropriate amount of blood circulating in the body, and blood purification can be automatically terminated. Thus, the burden on the medical staff is reduced, and rapid blood purification treatment adapted to each patient can be performed. In addition, blood purification conditions adapted to each patient can be set, and blood purification treatment can be performed for all types of patients, so that the costs associated with blood purification can also be reduced.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of the blood purification apparatus of the present invention when the blood purification device is a hemodialyzer or a hemodialysis filter.
FIG. 2 is a block diagram showing an embodiment when the blood purifier is a blood filter in the blood purification apparatus of the present invention.
FIG. 3 is a conceptual diagram showing the change over time of the operation of the blood purification apparatus of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Blood purification apparatus 2 Blood purification part 3 Blood purification device 4 Blood circuit 43 Blood pump 46 Fluid replacement part 5 Dialysate circuit 51 Water removal pump 56 Injection | pouring part 6 Measuring means 7 Control part

Claims (5)

In a blood purification apparatus comprising a blood purification unit, a blood parameter measuring means, and a control unit that converts the blood parameter into a blood volume and controls the blood purification unit based on the blood volume, the blood purification unit decreases as blood purification is performed. When the tending blood volume reaches a predetermined value, the control unit instructs the blood purification unit to change the blood purification condition so as to increase the blood volume, and the blood purification condition is changed. When the blood volume increases and reaches the next predetermined value or when a predetermined time has elapsed, the control unit changes the blood purification condition to the blood purification unit so as to decrease the blood volume. again the operation and instructing, to the control unit is repeated a plurality of times, when the increase rate of the blood amount per unit time in the blood volume increases life has reached the predetermined value decreases, the control unit is blood instructions purification exit the blood purification unit Blood purification apparatus characterized by having that function. The blood purification unit includes a hollow fiber membrane type blood purifier for purifying blood, a blood circuit connected to the inside of the hollow fiber membrane of the blood purifier and provided with a blood pump, and the blood purifier The blood purification apparatus according to claim 1, further comprising a circuit connected to the outside of the hollow fiber membrane and provided with a water removal pump, and the measuring means is provided on a blood circuit. . The blood purification apparatus according to any one of claims 1 and 2, wherein the blood purification unit further includes one or more of a fluid replacement unit, a dialysate temperature control unit, and a liquid injection unit. The blood purification apparatus according to claim 1, wherein the blood parameter is one of blood light transmittance, blood osmotic pressure, electrolytic mass, and electrical resistivity. The blood purification condition is one or more conditions selected from the group consisting of a water removal rate, a circulating blood flow rate, a replacement fluid rate, a dialysate concentration, a dialysate temperature, and a sodium chloride aqueous solution injection rate. Item 5. A blood purification apparatus according to Items 1 to 4.

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