JPH03264075A - Blood processor - Google Patents

Abstract

PURPOSE:To carry out blood processing free from the stagnation of blood in a blood inflow port even in the blood processing with low flow rate, without using an anticoagulation agent, by installing a flow rate control means for the blood which is sent by a constant pressure pump in a blood processor. CONSTITUTION:As for the blood flow in a blood processing device 1, the blood which is taken out of by a patient passes through the third blood feeding pipe 7, and the blood flow having a certain pressure is generated by a constant pressure pump 2, and the blood flows in the first blood feeding pipe 5, and flows into a blood processor 3 from the lower part of the blood processor 3, and after the necessary blood processing is carried out, the blood is returned into the patient through the second blood feeding pipe 6. If necessary, the flow rate of the blood stream which flows in the constant pressure pump 2 and the succeeding is varied intermittently by operating a flow rate control means 4 installed on the second blood feeding pipe 4, and the generation of the blood stagnation which is sometimes generated in the blood processor 3, in particular, in a blood inflow port is prevented.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a blood processing device.

In detail, there are artificial lungs that circulate blood through blood processing components to perform gas exchange such as adding oxygen and removing carbon dioxide, artificial dialyzers that perform hemodialysis, plasma separators that separate blood components, and blood The present invention relates to a blood processing device equipped with a blood processing device such as a blood purifier that performs adsorption purification of blood.

[Prior Art] Conventionally, as a blood processing device, for example, a hollow fiber membrane oxygenator has been available, and its boat-shaped structure stores a large number of gases in a cylindrical housing having an inlet and an outlet for oxygen-containing gas. A hollow fiber membrane bundle consisting of replacement hollow fiber membranes is inserted, and both ends of this hollow fiber membrane bundle are attached to both ends of the cylindrical housing.
It is fixed in a liquid-tight manner by a partition wall formed of a sorting agent, and a funnel-shaped blood port forming a blood inlet and a blood outlet is attached to the outside of this partition wall. The hollow fiber membranes used for gas exchange include porous polypropylene hollow fiber membranes, porous polyethylene hollow fiber membranes, and silicone rubber hollow fiber membranes.

In recent years, different from conventional blood processing, blood processing methods that involve long-term extracorporeal circulation have begun to be used. Specifically, extracorporeal assisted circulation (ECM) using a model oxygenator has been used. ○), continuous hemodialysis using an artificial dialyzer (CAVD), continuous hemofiltration using a hemofilter (
CAVH), etc.

Heparin, which is an anticoagulant, is added to the circulating blood in order to prevent blood coagulation inside the blood processing device. However, the longer the blood treatment lasts, the higher the dose of heparin will be, and the administration of heparin will reduce the blood coagulation ability of the patient undergoing blood treatment, which will delay the healing of other traumatic sites, surgical sites, etc. will be invited. Therefore, it is preferable to circulate blood with a smaller amount of heparin and to treat blood without administering heparin.

However, blood tends to stagnate inside the blood inflow port of the blood processing device (artificial lung) mentioned above, which can lead to the deposition of blood cells and even the formation of blood clots, making it difficult to perform heparin-reduced or heparin-free circulation. It is. In addition, the blood inflow port functions as a chamber for allowing blood to flow into the hollow fiber of the blood processing device, and the blood inflow port functions as a connection with the blood supply tube, so it may simply be omitted. I can't. Therefore, there are devices in which the shape of the blood inflow port is improved (for example, Japanese Patent Publication No. 62-54510 and Japanese Patent Publication No. 60-5308).

[Problems to be solved by the invention] However, by simply improving the shape of the blood inflow port as described above, it is not possible to suppress partial retention inside the blood port. In blood processing performed at such low flow rates, it is difficult to avoid partial stagnation inside the blood port, and there is an extremely high risk of thrombus formation within the blood port unless anticoagulants are used. Met.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned problems, and even when blood treatment is performed at a low flow rate, there is very little blood stagnation in the blood inflow port, and blood treatment is performed without using an anticoagulant. The purpose of the present invention is to provide a blood processing device that can perform the following steps.

Means for Solving Problem E] What achieves the above object of the present invention is a blood processing device having a constant pressure pump and a blood processor for processing blood sent by the constant pressure pump. The blood processing apparatus is a blood processing apparatus having a flow rate control means for blood delivered by the constant pressure pump.

The blood processing device includes a first blood supply tube that communicates the constant pressure pump and the blood treatment device, and a second blood supply tube connected to the blood treatment device, and the flow rate control means includes a first blood supply tube that communicates with the constant pressure pump and the blood treatment device. It is preferable to provide the first tube or the second tube. Further, it is preferable that the flow rate control means intermittently changes the flow velocity distribution of blood flowing within the blood processing device. Furthermore, it is preferable that the flow rate control means intermittently presses the first or second blood supply tube from the outside.

Furthermore, it is more preferable that the flow rate control means intermittently presses the first or second blood vessel from the outside without completely occluding the blood vessel. Preferably, the flow rate control means intermittently and gently changes the flow velocity distribution of blood flowing through the blood processing device. Further, the blood processing device includes a housing, a blood processing member housed in the housing, and a blood outflow port having a blood inflow port and a blood outflow port respectively attached to both ends of the housing. It is preferable that the device has at least a port. Furthermore, it is preferable that the blood contact surfaces of the blood processing device, the first blood vessel, and the second blood vessel be coated with an antithrombotic material. Preferably, a third blood supply tube is connected to the constant pressure pump. Further, the flow rate control means may be attached to the constant pressure pump. The blood processing device includes a housing, a blood processing member inserted into the housing, a partition wall that fluidly fixes both ends of the blood processing member to both ends of the housing, and a partition wall that fixes both ends of the blood processing member to both ends of the housing. A blood processing fluid inlet and an outlet that are provided near both ends and communicate with a space formed by one surface of the blood processing member, an inner surface of the housing, and a partition wall; Preferably, it has a blood inlet port having a blood inlet and a blood outlet port having a blood outlet respectively attached thereto.

The blood processing apparatus of the present invention will be explained in detail using embodiments shown in the drawings.

The blood processing device 1 of the present invention includes a constant pressure pump 2, a blood processor 3 for processing blood sent by the constant pressure pump 2, and a flow rate control means 4 for blood sent by the constant pressure pump 2. have.

Therefore, the blood processing apparatus 1 of the present invention has a flow rate control means 4.
By using this, it is possible to intermittently change the flow rate of the blood flow generated by driving the constant pressure pump, and to intermittently change the flow velocity distribution of blood flowing inside the blood processing device 1, especially inside the blood processing device 3. can be done. This change in the flow rate of the blood flow changes the flow of blood, that is, the flow velocity distribution, inside the blood processing device 3, especially inside the blood inflow port, and changes the flow velocity of blood that will form a stagnation part or a stagnation part in the future inside the blood port. To prevent the continuous formation of extremely low parts. Therefore, the occurrence of thrombus inside the blood processing device 3 can be prevented.

Therefore, the blood processing apparatus of the present invention will be explained using the embodiment shown in FIG.

The blood processing apparatus 1 of this embodiment includes a constant pressure pump 2, a blood processing device 3 for processing blood sent by the constant pressure pump 2, and a first blood feeding tube 5 connecting the constant pressure pump 2 and the blood processing device 3. , a flow meter 8 attached to the first blood vessel, a second blood vessel 6 connected to the blood processing device 3, a flow control means 4 attached to the second blood vessel 6, and a constant pressure pump 2 connected to the second blood vessel 6. It consists of a third blood supply tube 7.

The flow of blood in this blood processing device 1 is such that the blood removed from the patient passes through the third blood supply tube 7 and is given a constant pressure blood flow by the constant pressure pump 2, and then flows into the first blood supply tube 5. The blood flows into the blood processing device 3 from below the blood processing device 3 placed almost vertically, and after the necessary blood processing is performed, the blood is returned to the patient via the second blood supply tube 6. It is something that In addition, by activating the flow rate control means 4 attached to the second blood supply tube 4 as necessary, the flow rate of the blood flow flowing through the constant pressure pump 2 and subsequent parts is intermittently changed (pulsation is given), and blood processing is performed. This prevents the formation of blood stagnation or areas that may become stagnation areas that may form inside the vessel 3, particularly within the blood inflow port.

The constant pressure pump 2 used in the blood processing apparatus 1 of the present invention is one that pumps fluid at a constant pressure.

Centrifugal pumps, turbine pumps, screw pumps, etc. can be used as constant pressure pumps.

As the blood processing device 3, an artificial lung, an artificial kidney, a plasma separator, an adsorption type blood purification device, etc. are used. in particular,
A blood processing device or the like is used, which has a housing, a blood processing member housed in the housing, and a blood inflow port having a blood inlet and a blood outflow port having a blood outflow port attached to both ends of the housing, respectively. be done. Blood processing components include gas exchange membranes for artificial lungs, hemodialysis membranes for artificial kidneys, plasma separation membranes for plasma separators, and adsorption membranes for blood purifiers. agent is used.

A specific example of an artificial lung used as the blood processing device 3 is shown in FIG.

This oxygenator is a hollow fiber membrane type oxygenator 40, which includes a housing 46, a gas exchange hollow fiber membrane 42 which is a blood processing member inserted into the housing 46, and both ends of the hollow fiber membrane bundle. Partition wall 10 liquid-tightly fixed to both ends of 46
．． If and a blood processing chamber provided near both ends of the housing 46 and communicating with the space (oxygen chamber 12) formed by the outer surface of the hollow fiber membrane 42, which is a blood processing member, the inner surface of the housing 46, and the partition wall. It has an inlet 13 and a gas outlet 14 for gas as a fluid, and a blood inlet port 18 having a blood inlet 29 and a blood outlet 28 attached to both ends of the housing 46, respectively. are doing.

As the hollow fiber bundle housed in the cylindrical housing 36, the hollow fiber membrane for gas exchange has a cost of 10,000 to 60,000
A bundle of about 0 fibers is used, and the hollow fiber membrane 42 for gas exchange is a porous membrane having a large number of micropores passing through it. The hollow fiber membrane for gas exchange has an inner diameter of 10fl to 100011x.

Preferably 100 to 300μ11 Wall thickness 5 to 80μ11 Preferably 10 to 60μ11 Porosity 20 to 80%, preferably 30 to 60%, and the diameter of the micropores is 0.01 to 5μ
11 Preferably, about 0.01 to 1 μl is suitably used. Further, the membrane is not limited to a hollow fiber membrane, but may be a flat membrane.

Materials for hollow fiber membranes for gas exchange include polypropylene,
Polymer materials such as polyethylene, polytetrafluoroethylene, polysulfone, polyacrylonitrile, and cellulose acetate can be used, preferably hydrophobic polymers, particularly preferably polyolefin resins,
More preferably, polypropylene is used, and polypropylene in which micropores are formed by a stretching method or a phase separation method is desirable.

To specifically describe the structure of the hollow fiber membrane oxygenator 40 of this embodiment, both ends of the hollow fiber membrane 42 are fluid-tightly fixed to the housing 46 by partition walls 10°11 with their respective openings not being closed. ing.

The partition wall 10.11 divides the inside of the housing 46 into an oxygen chamber 12 formed by the hollow fiber membrane outer wall, the inner wall of the housing 46, and the partition wall, and a blood circulation space formed inside the hollow fiber membrane. Ru.

A blood inflow port 19 having a blood inflow port 29 and an annular convex portion 25 is fixed to the outside of the partition wall 11 with a screw ring 23, and a blood outflow port 28 is fixed to the outside of the partition wall IQ.
A blood outflow port 18 having an annular convex portion 24 is fixed by a screw ring 22. And blood port 18
．． The convex portion 24.25 of No. 19 is in contact with the partition wall 1°11, and a screw ring 2 is attached to the outer periphery of this convex portion 24.25.
2. At least two holes 3 provided in each of the 23
0.31.32.33. A sealant is filled from one side of the blood ports 18.19 to fluid-tightly fix each blood port 18.19 to the septum 10.11.

The flow rate control means 4 changes the flow rate of blood sent from the constant pressure pump 2 over time by changing the flow rate in the blood circuit of the blood processing device 1, thereby giving pulsation to the blood flow. be.

The flow rate control means 4 intermittently changes the cross-sectional area of the second blood vessel 6 to which this flow rate control means is attached, and specifically, intermittently presses the second blood vessel from the outside. If possible, a clamp is used which allows the cross-sectional area of the second blood vessel 6 to be varied. The clamp can be manually operated, electrically operated, pneumatically operated, or mechanically operated; for example, rotary solenoids, solenoid valves, air cylinders, eccentric cams, etc. are preferably used. be done.

Then, by operating the flow rate control means 4, the inside of the oxygenator, especially the blood inflow port! 9 can be eliminated. Specifically, blood that flows into the blood inflow port 19 at a constant flow rate is dispersed within the blood inflow port 19 with a certain flow velocity distribution. However, if a constant flow rate is continuously maintained, the flow velocity distribution formed within the blood inflow port 19 also becomes approximately constant. For this reason, partial retention or a portion where the flow velocity is extremely low compared to other portions is formed in the blood inflow port 19, which causes thrombus formation. Although locations where thrombi are likely to form differ depending on the shape of the blood inflow port 19 and the flow rate of blood to be inflowed, in the blood inflow port 19 having the shape in this embodiment, as shown in FIG. An annular retention area is likely to be formed in the center of the area. However, by operating the flow rate control means 4,
Because the blood flow rate changes intermittently, blood inflow port 1
The flow rate of the blood flow flowing into the port 9 also changes intermittently, and with this change, the flow velocity distribution of the blood flow inside the port 19 also changes. Therefore, a constant blood flow velocity distribution is not formed within the blood inflow port 19. The formation state of the retention portion formed in the blood inflow port 19 varies depending on the blood flow rate and flow velocity distribution in the blood inflow port, but by operating the flow rate control means 4 described above, the flow rate in the blood inflow port 19 can be changed. As a result, the flow velocity distribution changes, and as a result, the portions where the flow velocity is low and which may become stagnation portions are sequentially moved. Therefore, a portion where blood continues to accumulate at the same location and a portion where the flow rate is extremely low compared to other portions are not formed.

This flow rate control means 4, as shown in FIG.
This is particularly effective when the oxygenator is placed almost vertically and blood is allowed to flow in from below. Moreover, conversely, it may be used when blood is caused to flow in from above.

Furthermore, it is preferable that the flow rate control means 4 performs the operation without completely occluding the second blood vessel 4, and in the maximum stenosis state, the cross-sectional area of the second blood vessel 4 is reduced to the open state (non-stenotic state). It is preferable to set it to about 1750 to 175. By doing so, it is possible to suppress the occurrence of extreme pressure fluctuations in the blood circuit inside the blood processing apparatus. In other words, in the case of complete occlusion, a peak pressure called overshoot occurs where the pressure fluctuation becomes extremely high instantaneously when the tube is occluded. This phenomenon is similar to an electrical transient, after which the pressure value stabilizes.

However, by not completely blocking the tube, it is possible to suppress the occurrence of extreme peak pressures in this pressure fluctuation, and the risk of causing hemolysis in the blood flowing inside is reduced, which is preferable.

Further, the dual flow rate control means 4 may be configured to intermittently and gently change the flow velocity distribution of blood flowing through the blood processing device. Such means can be carried out by pressing the second blood supply tube not instantaneously but at a gentle speed using the flow rate control means 4. The specific stenosis rate varies depending on the blood processing device and blood vessel used, but is considered to be preferably about 5 cz/sec to 15 cz/sec. By doing this, even if the flow rate control means completely presses the tube,
As described above, it is possible to suppress the occurrence of extreme peak pressure in pressure fluctuations when the tube is completely occluded, which is preferable because the risk of causing hemolysis in the blood flowing inside the tube is reduced.

Moreover, the time interval of the stenosis of the second blood vessel 6 is cycle (
1 cycle - 1 cycle of stenosis time + opening time) 0.4 to 3
．． Approximately 0 seconds, stenosis time is IO% to 60% of one cycle
It is preferable to set it as approximately.

Further, the flow rate control means 4 may be attached not to the second blood supply tube but to the first blood supply tube 5 that connects the constant pressure pump 2 and the blood processing device 3, as shown in FIG. It may also be attached directly to the constant pressure pump 2 as shown in the figure.

As the first tube 5, the second tube 6, and the third tube 7, transparent flexible synthetic resin tubes such as vinyl chloride resin and silicone rubber can be suitably used. Further, if necessary, as shown in FIG. 2, a blood reservoir 9 may be provided in the third blood vessel 7.

Furthermore, it is preferable to attach a flowmeter 8 to one of the blood vessels. This is because when a constant pressure pump, particularly a centrifugal pump, is used, it is difficult to check the flow rate from the rotational speed of the pump, so it is preferable to provide this for checking the flow rate.

The flow meter 8 is preferably one that can measure the flow rate of blood flowing inside the blood vessel without directly contacting the blood, and for example, an ultrasonic flow meter is preferably used.

Furthermore, the blood contact surface of the blood processing device 1 of the present invention, in particular,
Preferably, an antithrombotic material is fixed to the blood contact surfaces of the blood processing device 3 and the blood supply tube. Examples of antithrombotic materials include heparin, polyalkylsulfone, ethyl cellulose, acrylic ester polymers, methacrylic ester polymers (e.g., polyHEMA [polyhydroxyethyl methacrylate]), hydrophobic segments and hydrophilic segments. Block or graft copolymers containing both (e.g., HEMA-styrene-HEMA block copolymers, HEMA-MMA [methyl methacrylate] pro-copolymers, HEMA-LMA
Block copolymer of [lauryl methacrylate], P
A block copolymer of VP [polyvinylpyrrolidone]-MMA, a blend polymer obtained by mixing this block copolymer with a polymer having an amino group), a fluorine-containing resin, and the like can be used. Preferably HEMA
- Styrene HEMA block copolymer, HEMA-M
Block copolymers of MA [methyl methacrylate] and the like are preferred. After coating the blood-contacting surface with the above-mentioned hydrophilic resin excluding heparin, it is preferable to further fix heparin thereon. In this case, in order to fix heparin on the surface of this hydrophilic resin, the hydrophilic resin must be
Contains or can be easily converted into a hydroxyl group, an amino group, a carboxyl group, an epoxy group, an incyanate group, an epoxy group, a thiocyanate group, an acid chloride group, an aldehyde group, and a carbon-carbon double bond It is preferable that it has a group such as Particularly preferably,
A blend polymer obtained by mixing the above-mentioned hydrophilic resin with a polymer having an amino group is used, and the polymer having an amino group is preferably a polyamine, particularly PEI [polyethinimine].

Heparin fixation is carried out by coating the blood-contacting surface of a blood processing device with the above-mentioned hydrophilic resin, and then contacting the surface with an aqueous heparin solution. .By covalent bonding to the above hydrophilic resin by contacting with a fixing agent such as 4-tolylene diisocyanate, carbodiimide-modified diphenylmethane diisocyanate, epichlorohydrin, Can be fixed.

[Example] Next, an embodiment of the blood processing apparatus of the present invention will be described.

(Example 1) A hollow fiber membrane oxygenator was used as a blood processor.

The hollow fiber membrane oxygenator has a shape as shown in Figure 4. Specifically, it is made of polycarbonate and has a cylindrical shape with a gas inflow port and an outflow port near the end. Housing (inner diameter 58xz, length 120
131+), with an inner diameter of approximately 200μ degrees and a wall thickness of approximately 25μ! Approximately 12,000 polypropylene hollow fiber membranes with a porosity of 45% and an average pore diameter of approximately 700 were inserted, and after centrifugally injecting a po-noting agent (polyurethane) through the gas inlet and gas outlet of the housing, potting was performed. A device with a membrane area of 0.8 m in which each blood port is fixed to the outside of the housing (end face of the partition wall) using a screw ring is used. there was.

As the constant pressure pump, a BioPump (manufactured by Biomedix Co., Ltd.) was used, and as the flow rate control means, an air cylinder with a speed control was used, which had a mechanism that allowed the opening and closing time of the cylinder to be set arbitrarily. Then, the blood inlet of the constant pressure pump has an inner diameter of 6111 mm.
Connect the PVC tube No. 1, and connect the blood outflow port of the constant pressure pump and the blood inflow port of the oxygenator with a PVC tube with an inner diameter of 6 mm, and connect the blood outflow port of the oxygenator with a PVC tube with an inner diameter of 6
A vinyl chloride tube 11 was connected, and the above flow rate control means was attached to this tube. Furthermore, a flow meter [transit time blood flow meter] is installed downstream of this flow rate control means.
Transonic 01 (manufactured by Advance Co., Ltd.)] was installed to create a blood processing device of the present invention.

(Example 2) As a hollow fiber membrane type oxygenator, the one in Example 1 was used, and further, heparin was fixed on the blood contact surface of this oxygenator.

For fixing heparin on the blood contact surface of the oxygenator, acrylic resin [P (HEMA) and PE
1.25% of I each.

0.75%/methanol: methyl cellosolve: water = 89
, 2:8.3:2.5] and then coated with 10
% heparin aqueous solution (containing 0.25N H, So,) at 97°C for 10 minutes, and then treated with a 0.2% aqueous solution of modified heparin (pH 4°C, containing partially amino groups).
After contacting with 0.1M citrate buffer), 45℃, 4
After contacting with 0.5% geltaraldehyde aqueous solution (pH 4.0, O, 01M citrate buffer), treatment was performed at 37°C for 20 hours to inject heparin into the blood contact surface of the oxygenator. were covalently bonded.

Furthermore, a tube with heparin fixed on the blood contact surface was used. To fix heparin to the tube, use an ozone generator (manufactured by Japan Ozone Co., Ltd.) to fix the heparin to the tube at 0.8f2/m1no, 500C for 2 hours.
After being treated for 0 minutes, it was brought into contact with 0.5% pH (pH 10,0) and further treated for 45°CCl2O hours. Subsequently, a 10% aqueous heparin solution (containing 025NH, So,
, 1M citrate buffer) at 45°C, 4
After contacting with 0.5% geltaraldehyde aqueous solution (pH 4, 0° 0.01M citrate buffer), treatment was performed at 37°C for 20 hours to transfer heparin to the blood contact surface of the tube. Combined.

In addition, for the connectors used in the pump and circuit, heparin is fixed on the blood contact surface in the same way as in the oxygenator described above, and for the cannula attached to the open end of the tube, the blood contact surface is fixed. Heparin was fixed on the surface in the same manner as in the chinift described above. A blood processing device of the present invention was created using the same device as in Example 1 except for the above points.

[experiment] (Experiment 1) The following experiment was conducted using the blood processing apparatus of Example 1.

The experimental circuit shown in FIG. 5 was used. In addition,
60 is an experimental liquid tank, 64, 66, 68 are pressure gauges, and 62 is a liquid mixing port. In addition, as the experimental liquid, we used an almost neutral solution of 0.9% NaCl and 35% glycerin (approximately the same viscosity as blood) to which a small amount of Fe/-Luckrein was added, and operated the centrifugal pump 2. The experimental liquid was circulated. Then, - temporarily stop the centrifugal pump 2, inject the above experimental liquid with lcc of alkaline liquid to which Mail has been added to a concentration of 0.02N from the mixed injection port, and inject the above into the blood inflow port of the oxygenator. After the alkaline liquid was almost uniformly diffused (changed to red), 50 μQ of lNHCl was added into the tank 60, and the experimental liquid was circulated at a flow rate of 100 s + 12/sin while operating the clamp 4 under the following conditions. The time required for the fae/-lufthalein in the blood port to become colored or disappear was measured, and the disappearance pattern was observed. The experimental conditions are as shown below.

[Experimental Conditions A (Example)] The tube was repeatedly constricted and opened with a clamp opening time of 0.8 seconds and a clamp constriction time (time from output of a pressure start signal to output of a suppression release signal) of 0.6 seconds. The clamp stenosis speed was confirmed by photographing with a strobe light, and was found to be 30 cx/sec at the moment the tube began to be pressed. Note that the tube was completely occluded for stenosis. The time for complete occlusion (maximum stenosis state time) was 0.45 seconds, as determined by reading the pressure change on a polygraph chart.

[Experimental Conditions B (Example)] Experimental Conditions B were the same as Experimental Conditions A, except that the stenosis of the tube was not completely occluded, and the minimum distance in the cross section of the tube was approximately 1 su+ in the maximum stenosis state. .

[Experimental Conditions C (Example)] The same conditions as Experimental Conditions A were used except that the clamp stenosis rate was slower than that of Experimental Conditions A. It was confirmed by photographing with a stropholight that the clamp stenosis rate was 5 cw/sec at the moment when the tube began to be pressed. The time for complete occlusion (maximum stenosis state time) was 0.1 to 0.2 seconds.

[Experimental Condition D (Comparative Example) Same as Experimental Condition A except that the co-clamp was not operated.

The experimental results regarding the color disappearance time are as shown in Table 1.

Table 1 Also, under experimental condition A, the color loss pattern was such that after the outer periphery of the blood port became colorless, the pink part at the center became a tree ring shape and moved outward and disappeared. In addition, experimental conditions B and C were almost the same as experimental condition A, but the annual rings were clearer than in experimental condition A.

Under the experimental conditions, the coloring on the outer periphery disappears relatively quickly, but as shown in FIG.
As shown in the figure, retention of the colored portion 41 in the center of the blood port 40 was confirmed.

(Experiment 2) Using the experimental circuit used in Experiment 1, the experimental liquid was circulated at an average flow rate of 400 m12/sin, and experimental conditions A-
The pressure fluctuations under the conditions of D are measured by the pressure gauge 64 (P 1
), 66 (P 2 ), and 68 (P 3 ).

As a result, under experimental condition A, the clamp was ON.

PL when OFF, P2. In all of P3, instantaneous extreme pressure fluctuations occur, and in all of P2. Decompression also occurred at P3. In addition, instantaneous changes in flow due to opening and closing of the clamp were observed using a flowmeter, and backflow was observed. This is thought to be due to the inertia of the fluid and the rapid change in volume within the blood circuit when clamping the tube.

Under experimental condition B, Pi, P2. In both cases P3, pressure fluctuations were gentle, and no depressurization or backflow was observed. In addition, under experimental condition C, the opening and closing speed of the clamp is slow, so the pressure fluctuation rises slowly, and P
At L and P2, no decompression occurred. However, at P3, an instantaneous decompression occurred at the moment of complete occlusion of the clamp. A faint backflow was also confirmed.

Instantaneous extreme pressure fluctuations and changes in flow may cause hemolysis, and the occurrence of depressurization at PI and P2 may cause air bubbles when using a porous membrane type oxygenator. may flow into the blood, which is not preferable. Under experimental conditions B and C, it seems that there is no such fear. Therefore, in order to prevent the occurrence of extreme pressure fluctuations (extremely high peak pressure) when the tube is suddenly and completely occluded, and to ensure problem-free pressure fluctuations, the clamp opening/closing speed should be 5 to L5.
It is thought to be about cx/sec.

(Experiment 3) Using the blood processing apparatus of Example 2, carotid artery and vein VA Bypass was performed on a mongrel dog for 24 hours. In the experiment, the blood flow was 350112/+in, a 20 kg mongrel dog was used, and non-heparin was used. The flow rate control means in the blood processing apparatus was controlled under experimental conditions A- in Experiment 1.
After completion of blood circulation, the artificial lung was washed with physiological saline, and the state of adhesion of blood cells on the inner surface of the blood port and the state of thrombus formation were confirmed. As a result, experimental condition A-
In case C, adhesion of blood cells and occurrence of thrombus on the inner surface of the blood port of the oxygenator were not observed. On the other hand, under the experimental conditions, as shown in FIG. 6 and FIG. 7, which is a cross-sectional view of the center of FIG. Ta.

[Effects of the Invention] The blood processing device of the present invention includes a constant pressure pump and a blood processor for processing blood sent by the constant pressure pump, and the blood processing device includes: Since the apparatus has a flow rate control means for the blood sent by the constant pressure pump, by using the flow rate control means, the flow rate of the blood flow generated by driving the constant pressure pump can be changed, and the flow rate within the blood processing apparatus can be changed. In particular, it is possible to change the flow velocity distribution of blood flowing inside the blood processing device. This change in the flow rate of the blood flow changes the blood flow, that is, the flow velocity distribution, inside the blood processing device, especially in the blood inflow part, and causes extremes in the blood flow velocity that may form a stagnation part or a future stagnation part inside the blood inflow part. This prevents low areas from continuing to form. Therefore, it is possible to prevent the occurrence of thrombus inside the blood processing device.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an embodiment of the blood processing apparatus of the present invention;
2 and 3 are schematic diagrams of other embodiments of the blood processing device of the present invention, and FIG. 4 is a sectional view showing an example of a blood processing device used in the blood processing device of the present invention. FIG. 5 is a schematic diagram of the circuit used in the experiment of the blood processing apparatus of the present invention, and FIGS. 6 and 7 are explanatory diagrams of the experimental results. 1...Blood processing device, 2...Constant pressure pump, 2.
...Blood processing device, 4...Flow rate control means, 5...
1st blood vessel, 6...2nd blood vessel, 7...3rd
Blood supply tube, Figure 1, Figure 2, Figure 4

Claims (8)

[Claims] (1) A blood processing device having a constant pressure pump and a blood processing device for processing blood sent by the constant pressure pump, the blood processing device being configured to process blood sent by the constant pressure pump. A blood processing device characterized by having a flow rate control means. (2) The blood processing apparatus includes a first blood supply tube that communicates the constant pressure pump and the blood treatment device, and a second blood supply tube connected to the blood treatment device, and the flow rate adjustment means includes the The blood processing device according to claim 1, which is attached to the first blood vessel or the second blood vessel. (3) The blood processing device according to claim 1, wherein the flow rate control means intermittently changes the flow velocity distribution of blood flowing within the blood processing device. (4) The blood processing apparatus according to claim 3, wherein the flow rate control means intermittently presses the first or second blood supply tube from the outside. (5) The blood processing apparatus according to claim 3, wherein the flow rate control means intermittently presses the first or second blood vessel from the outside without completely occluding the blood vessel. (6) The blood processing apparatus according to claim 3, wherein the flow rate control means intermittently and gently changes the flow velocity distribution of blood flowing within the blood processing device. (7) The blood processing device includes a housing, a blood processing member housed in the housing, and a blood inflow port and a blood outflow port respectively attached to both ends of the housing. 7. The blood processing device according to claim 1, further comprising an outflow port. (8) The blood processing device according to any one of claims 1 to 7, wherein the blood contact surfaces of the blood processing device, the first blood vessel, and the second blood vessel are coated with an antithrombotic material. .