JP2004008586A - Fluid circulating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid circulating apparatus with which a circulation state is made to resemble that of blood in a living body, and the blood compatibility of an artificial organ and a base material is easily and reliably evaluated, or the like, even when an animal experiment is not performed or the number of the experiments is reduced compared with a conventional method. <P>SOLUTION: This fluid circulating apparatus 10 includes: a drive pump 12 for generating a beat stream; and a circulation flow path 13 which is arranged between the flow-out port 19 and the flow-in port 20 of the drive pump 12. The circulation flow path 13 is constituted to allow blood discharged from the flow-out port 19 of the drive pump 12 to flow into the flow-in port 20 by non-contact with outer air. The apparatus 10 also includes: a resistance giving means 23 for giving flow resistance to the blood; and a second connection pump 30 which is arranged on the downstream side of the means 23, so as to attenuate the pressure pulse of the blood. Thus, the blood is circulated in the state resembling the circulation of the blood in the living body. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a fluid circulating device, and more particularly, to a fluid circulating device that can simulate the circulation state of blood in a living body and is suitable for investigating blood compatibility of artificial organs and raw materials.
[0002]
[Prior art]
Artificial organs and materials that come into contact with the blood of the human body (hereinafter referred to as artificial organs, etc.) must have good compatibility with blood, and it is necessary to thoroughly investigate the blood compatibility before commercialization. It is. Here, as a method for examining blood compatibility, an artificial organ or the like is arranged in the middle of a circulation flow path formed by connecting a predetermined pump and a blood pack with a tube, and blood in the circulation flow path is constantly flowed. There is known a method of investigating and evaluating blood compatibility of an artificial organ or the like by circulating it in a state.
[0003]
[Problems to be solved by the invention]
However, blood circulating in the human body generates a predetermined pulsatile flow in an artery due to pulsation of the heart, peripheral resistance, and the like, and the pulse pressure when returning from the vein to the heart is approximately 0 mmHg. For this reason, in the above-mentioned investigation method performed under a steady flow, since the investigation cannot be performed according to the blood circulation state in the human body, the following inconveniences are caused. In other words, even if an artificial organ or the like is determined to have good blood compatibility by the above-described investigation method, it becomes incompatible under the circulating state of blood in a living body. Even if the material is judged to be high, a thrombus may occur under pulsatile flow. Therefore, in order to reliably evaluate the blood compatibility of an artificial organ, it is essential to conduct an animal experiment that can be conducted in a state close to the state of blood circulation in the human body after the investigation by the above-described method. However, in this case, not only does blood compatibility investigation become troublesome twice, but also in animal experiments, it takes time to secure animals and to attach artificial organs to the animals. There is a disadvantage that it cannot be easily investigated. There is also an ethical problem that many animals are sacrificed.
[0004]
[Object of the invention]
The present invention has been devised in view of such inconveniences, and its object is to simulate the state of blood circulation in a living body, and to carry out animal experiments without performing animal experiments. It is an object of the present invention to provide a fluid circulating apparatus that can easily and reliably evaluate the blood compatibility of artificial organs and material materials even if the number of times is smaller than in the past.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention includes a drive pump for generating a pulsating flow, and a circulation flow path disposed between an outlet and an inlet of the drive pump, and the drive pump operates to In a fluid circulation device that circulates the fluid in the circulation flow path,
The circulation flow path includes a resistance applying unit that applies a flow resistance to the fluid, and a pulse pressure attenuating unit that is disposed downstream of the resistance applying unit and attenuates a pulse pressure of the fluid. The fluid is circulated in a state simulating circulation. According to such a configuration, since the fluid circulates in the device in a state simulating the circulation of blood in the living body, animal experiments are not performed by installing an artificial organ or a material at a site where the fluid flows. Even if the number of animal experiments is reduced compared to the conventional method, the evaluation of blood compatibility of artificial organs and raw materials can be performed simply and reliably.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
In the present invention, it is preferable to adopt a configuration in which the circulation flow path includes an amplitude adjusting means for adjusting the amplitude of the pulse pressure on the upstream side of the resistance applying means. With this configuration, it is possible to investigate the blood compatibility of an artificial organ or the like under various conditions in which the pulse pressure of the fluid is arbitrarily changed. Here, it is preferable that the amplitude adjusting means is constituted by an adjusting tube capable of adjusting the amplitude by changing the thickness.
[0007]
Further, the drive pump includes a peripheral wall having a substantially conical shape, and a diaphragm closing the peripheral wall from the bottom side,
The peripheral wall includes an outflow port provided at the top thereof and having an upper end serving as the outflow port, and an inflow port extending substantially tangentially to a main portion connected to the top and having a leading end serving as the inflow port. ,
The drive pump has a configuration in which the displacement of the diaphragm changes the volume of a space formed inside the peripheral wall, and discharges the fluid flowing into the space while generating a swirling vortex. Is preferred. According to such a configuration, the flow of the fluid in the drive pump can be made smooth with almost no stagnation region of the flow in the drive pump. For this reason, it is possible to avoid various problems caused by the stagnation region of the flow, for example, formation of a thrombus when the fluid is blood, and to more reliably evaluate the blood compatibility of an artificial organ or the like. it can. Here, by configuring the pulse pressure attenuating means by a pump having substantially the same configuration as that of the drive pump, the number of types of components constituting the apparatus can be reduced, thereby making it possible to reduce the cost of the entire apparatus. .
[0008]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0009]
FIG. 1 is a configuration diagram schematically illustrating a fluid circulation device according to the present embodiment. In this figure, a fluid circulating device 10 is provided so as to circulate blood as a fluid in a predetermined flow path in a state simulating the circulation of blood in the human body. Used for gender research. The fluid circulating device 10 is provided with a known suction / intake device 11, a polyurethane drive pump 12 connected to the suction / intake device 11, and blood discharged from the drive pump 12 returning to the drive pump 12. And a closed loop circulation channel 13.
[0010]
The suction and air supply device 11 has a known structure provided to be capable of suction and air supply to the drive pump 12, and a detailed description thereof is omitted here.
[0011]
The drive pump 12 is a pulsating flow pump having a structure that does not easily generate a stagnation area of blood with respect to blood contained therein. A pulsatile flow can be generated. That is, as shown in FIGS. 2 and 3, the drive pump 12 is fixed to the peripheral wall 15 having a substantially conical shape and the peripheral wall 15 so as to close the peripheral wall 15 from the lower end side in FIG. A cap-shaped bottom wall 16 swelling downward in the figure from the outer peripheral side toward the center, and an inner space surrounded by the peripheral wall 15 and the bottom wall 16 are divided into two upper and lower spaces A1 and A2 in FIG. It is constituted by the diaphragm 17. Here, the space A1 located on the upper side in FIG. 3 is connected to the circulation flow path 13 side, so that blood circulating in the circulation flow path 13 is accommodated. On the other hand, the space A <b> 2 located on the lower side in FIG. 3 is in a state of being isolated from the circulation channel 13 and connected to the suction / intake device 11.
[0012]
The peripheral wall 15 is a flange-like hem 15A which is a mating surface with the peripheral edge 16A of the bottom wall 16, a top 15B located at the upper end side in FIG. 3, and is connected between the hem 15A and the top 15B. It is composed of a curved surface-shaped main portion 15C. The top portion 15B and the main portion 15C are formed with an open-end cylindrical outlet port 19 and an inflow port 20 which are connected to the circulation channel 13, respectively. The outflow port 19 located on the top 15B side is a port for discharging the blood in the space A1 to the circulation flow path 13, and the tip side is an outflow port 19A. The inflow port 20 is a port for taking blood from the circulation channel 13 into the space A1, and the leading end side is an inflow port 20A. Here, the inflow port 20 is formed so as to extend in a substantially tangential direction with respect to the main portion 15C with the lower end side of the main portion 15C as a base, and is not particularly limited. It is inclined about 60 degrees with respect to the extending direction. Thereby, the blood that has entered the space A1 from the inflow port 20 can rise upward while generating a swirling vortex with almost no stagnant area from the lower part to the upper part of the space A1, as shown by the dotted line in FIG. Become.
[0013]
The bottom wall 16 is provided with a vent 22 on the peripheral surface thereof, and the vent T is connected to a tube T which is connected to the suction / intake device 11. Accordingly, in the space A2 located inside the bottom wall 16, the intake and exhaust by the operation of the intake and air supply device 11 are alternately performed.
[0014]
The diaphragm 17 is formed in the shape of a flexible thin disk, and its peripheral edge 17A is fixed by being sandwiched between a skirt 15A of the peripheral wall 15 and a peripheral edge 16A of the bottom wall 16. I have. Therefore, the diaphragm 17 is displaced toward one of the spaces A1 and A2 except for the peripheral portion 17A in accordance with the suction and exhaust in the space A2 by the operation of the suction and air supply device 11 (two points in FIG. 3). It changes to a dome shape with the top at the approximate center.
[0015]
In the drive pump 12 having the above configuration, when the air in the space A2 is sucked by the suction / intake device 11, the diaphragm 17 is displaced in a direction of decreasing the volume of the space A2 (downward in FIG. 3). The volume of the space A1 increases so that blood is sucked into the space A1. On the other hand, when air is supplied into the space A2 by the suction / intake air device 11, the diaphragm 17 is displaced in a direction of increasing the volume of the space A2 (upward in FIG. 3), whereby the volume of the space A1 decreases. Then, blood is discharged to the circulation channel 13. Then, the above operation is repeatedly performed, and a pulsating flow of blood is generated in the circulation channel 13. As will be described later, first and second check valves 36 and 37 (see FIG. 1) are provided in the circulation flow path 13 to prevent backflow of blood in the space A1. In the present embodiment, the pressure (positive pressure) of the air supplied into the space A2 is set to about 140 mmHg to 260 mmHg, while the pressure (negative pressure) of the air sucked from the space A2 is: It is set to about −30 mmHg to −50 mmHg.
[0016]
As shown in FIG. 1, the circulation flow path 13 has a flow path configuration in which blood discharged from the outflow port 19 of the drive pump 12 can flow into the inflow port 20 in a state where the blood is not in contact with the outside air. . That is, the circulation flow path 13 includes a resistance applying unit 23 that applies flow resistance to blood discharged from the outflow port 19, an upstream tube 24 connected to the outflow port 19, and a downstream side from the upstream tube 24. An adjusting tube 25 as an amplitude adjusting means connected to the control tube 25; a connecting tube 26 disposed downstream of the adjusting tube 25; and a downstream end of the connecting tube 26 A downstream tube 27 connected to the port 20, a first connection pump 29 provided between the adjustment tube 25 and the connection tube 26, and a second connection pump provided between the connection tube 26 and the downstream tube 27. A connection pump 30 is provided. A known connector 34 is used for connecting the members 23 to 30 here. By the way, in the following, for convenience of description, the upstream side of the circulation flow path 13 across the resistance applying means 23 is referred to as an arterial path L1, and the downstream side is referred to as a venous path L2.
[0017]
The resistance applying means 23 is provided at one position in the connecting tube 26 in consideration of the peripheral resistance of the human body, and is constituted by a pinch-like member for tightening the connecting tube 26, although not shown. I have. That is, by tightening the connection tube 26 by the resistance applying means 23, even if the drive pump 12 pulsates, the diastolic blood pressure in the arterial tract L1 does not become 0 mmHg, and the blood flow in the artery of the human body is simulated. Has become. Here, the average pulse pressure in the arterial tract L1 can be adjusted to a predetermined value by the degree of tightening of the connection tube 26. In the present embodiment, the average pulse pressure is 100 mmHg, which is substantially equivalent to the average pulse pressure of the human body. It has been adjusted to the extent. In addition, as the resistance applying means 23, other members such as a variable diaphragm can be adopted as long as the above-described operation is achieved, in addition to the above-described pinch-shaped member.
[0018]
Each tube except the adjustment tube 26 is not particularly limited, but is formed of vinyl chloride. Here, in the upstream tube 24 and the downstream tube 27, first and second check valves 36 and 37 for preventing the backflow of the blood so that the blood circulates reliably in the direction of the arrow in FIG. 1 are provided. Is provided. Although not shown, an electromagnetic flowmeter having a known structure may be mounted in the upstream tube 24 or the like to measure the blood flow rate in the arterial tract L1.
[0019]
The adjustment tube 25 is arranged upstream of the resistance applying means 23 and adjusts the amplitude of the pulse pressure of the arterial tract L1. That is, the adjustment tube 25 is formed of a soft material that can adjust the amplitude of the pulse pressure in the arterial tract L1 by changing its thickness, and is formed of, for example, segmented polyurethane or silicon. In the present embodiment, the amplitude of the pulse pressure in the arterial tract L1 is set to be ± 20 mmHg of the average pulse pressure (100 mmHg) like a human body.
[0020]
As the first and second connection pumps 29 and 30, pulsating flow pumps having the same configuration as the drive pump 12 are used, and the same or equivalent components to the drive pump 12 are the same. The description is omitted using the reference numerals. The connection pumps 29 and 30 are also mounted such that blood flows in from the inflow port 20 and is discharged from the outflow port 19. Here, each ventilation port 22 of each connection pump 29, 30 is open to the outside, so that the diaphragm 17 (see FIGS. 2 and 3) is displaced in accordance with the flow of blood. In addition, the amount of blood to be filled in the device is slightly smaller than the maximum filling amount allowed by the device, whereby the displacement of the diaphragm 17 of each connection pump 29, 30 is physically allowed. Slightly smaller than the maximum displacement. Thereby, the first connection pump 29 provides the same effect as that of the adjustment tube 25 by appropriately selecting the material and the size of the diaphragm 17 and adjusting the amplitude of the pulse pressure of the blood in the arterial tract L1. It can be used as amplitude adjusting means for performing the adjustment. On the other hand, the second connection pump 30 provided in the middle of the intravenous line L2 is provided with a damper effect that causes a pressure loss when blood passes through the inside. Therefore, the second connection pump 30 is arranged on the downstream side of the resistance applying means 23 and constitutes a pulse pressure attenuating means for attenuating the pulse pressure of the blood in the venous line L2. In the present embodiment, the blood pressure passing through the second connection pump is set to be approximately 0 mmHg corresponding to the left atrial pressure of the human body.
[0021]
Next, the operation of the fluid circulation device 10 will be described.
[0022]
When the suction / inhalation device 11 operates, the drive pump 12 pulsates as described above, and blood circulates in the circulation channel 13. That is, the blood discharged from the drive pump 12 flows in the arterial tract L1, and has a pulse pressure in the arterial tract L1 which substantially corresponds to a general aortic pressure of a human body. After passing through the resistance applying means 23 corresponding to the peripheral resistance of the human body, the blood passes through the second connection pump 30 and becomes a pulse pressure of approximately 0 mmHg substantially corresponding to the left atrial pressure of the human body. Inflow.
[0023]
If the drive pump 12 and the circulation channel 13 are accommodated in a thermostat (not shown), the circulating blood can be maintained at a temperature of about the human body temperature (about 37 ° C.).
[0024]
Such a fluid circulating device 10 is mainly used as an in vitro circuit for investigating the blood compatibility of artificial organs such as raw materials and artificial hearts, artificial valves, artificial blood vessels, etc. which come into direct contact with blood. Can be Here, when investigating the raw material, the raw material to be investigated may be attached or applied to the inner wall portions of the pumps 12, 29, 30 and the tubes 24 to 27, and the state of the inner wall portions may be evaluated. When investigating an artificial heart, an artificial heart to be inspected is used instead of the drive pump 12, and when investigating an artificial valve, an artificial valve to be inspected is used instead of the check valves 36 and 37. When investigating an artificial blood vessel, the state of each artificial organ may be evaluated by using an artificial blood vessel to be investigated instead of any of the tubes 24 to 27.
[0025]
Therefore, according to such an embodiment, the fluid circulation device 10 simulating the circulation state of the blood of the human body can eliminate or reduce the number of secondary research experiments such as animal experiments. And the blood compatibility of the raw materials can be easily and reliably checked.
[0026]
The fluid circulation device 10 according to the present invention is not limited to the channel configuration of the above-described embodiment, and may employ various channel configurations as long as substantially the same operation can be achieved. For example, the number of connection pumps 29 and 30 can be increased or decreased, or the drive pump 12 can be replaced with a pulsating flow pump having another configuration.
[0027]
Further, the fluid circulation device 10 can be applied to a bioreactor using a predetermined culture solution or the like as a fluid instead of blood, in addition to the above-described use for investigating blood compatibility of an artificial organ or the like. It can also be used for decellularization from animal tissues.
[0028]
【The invention's effect】
As described above, according to the present invention, it is possible to examine the blood compatibility of artificial organs and material materials with a device simulating the state of blood circulation in a living body, without performing animal experiments, or Even if the number of experiments is reduced as compared with the related art, it is possible to easily and reliably evaluate the blood compatibility of artificial organs and raw materials.
[Brief description of the drawings]
FIG. 1 is a configuration diagram schematically showing a fluid circulation device according to the present embodiment.
FIG. 2A is a schematic perspective view of a drive pump, and FIG. 2B is an exploded perspective view of FIG.
FIG. 3 is a schematic longitudinal sectional view of the drive pump along the line AA in FIG. 2 (A).
[Explanation of symbols]
Reference Signs List 10 fluid circulation device 12 drive pump 13 circulation flow path 15 peripheral wall 15B top 15C main part 17 diaphragm 19 outflow port 19A outflow port 20 inflow port 20A inflow port 23 resistance applying means 25 adjusting tube (amplitude adjusting means)
29 1st connection pump (amplitude adjustment means)
30 second connection pump (pulse pressure damping means)
A1 space

Claims (5)

A fluid pump for generating a pulsatile flow, and a circulation channel disposed between an outlet and an inlet of the drive pump, wherein the drive pump operates to circulate fluid in the circulation channel. In the device,
The circulation flow path includes a resistance applying unit that applies a flow resistance to the fluid, and a pulse pressure attenuating unit that is disposed downstream of the resistance applying unit and attenuates a pulse pressure of the fluid. A fluid circulation device, wherein the fluid circulates in a state simulating circulation. The fluid circulation device according to claim 1, wherein the circulation flow path includes an amplitude adjusting unit that adjusts the amplitude of the pulse pressure on an upstream side of the resistance applying unit. 3. The fluid circulating device according to claim 2, wherein the amplitude adjusting means is constituted by an adjusting tube capable of adjusting the amplitude by changing a wall thickness. The drive pump includes a substantially conical peripheral wall, and a diaphragm closing the peripheral wall from the bottom side,
The peripheral wall includes an outflow port provided at the top thereof and having an upper end serving as the outflow port, and an inflow port extending substantially tangentially to a main portion connected to the top and having a leading end serving as the inflow port. ,
The drive pump is characterized in that, when the diaphragm is displaced, the volume of a space formed inside the peripheral wall changes, and the fluid flowing into the space is discharged while generating a swirling vortex. Item 4. The fluid circulation device according to item 1, 2 or 3. The fluid circulation device according to claim 4, wherein the pulse pressure damping means is configured by a pump having substantially the same configuration as the drive pump.

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