JPS6144031B2 - - Google Patents

Description

[Detailed description of the invention]

() Background Art (-1) Technical Field The present invention relates to a method for removing air bubbles from blood flowing through an extracorporeal circulation blood circuit such as an artificial heart-lung machine, an artificial kidney machine, or a blood cell component and plasma component separation device during open-heart surgery. This invention relates to a bubble removing device. (-2) Prior art and its problems The blood bubble removal device uses an overbody method in which air bubbles in the blood are captured and removed by an overbody, and a blood retention space is provided to reduce the blood flow velocity. There are two methods: a retention method in which air bubbles in the blood rise due to buoyancy, and a combination method of overbody and blood retention. FIGS. 1 and 2 show conventional blood bubble removal devices using a filtration method, respectively. The device shown in FIG.
The container 1 is vertically divided into a blood chamber 3 to be processed and a blood chamber 4 to be processed, and a blood inlet 5 and a blood outlet 6 are provided at the bottom of the container 1 to communicate with each chamber. This configuration has a bubble outlet 7 that communicates with the air bubbles. Therefore, when the blood introduced into the blood chamber 3 to be processed from the blood inlet 5 passes through the overbody 2 due to blood flow pressure, air bubbles larger than the pore diameter of the overbody 2 are captured and enter the blood chamber 4 to be processed, which enters the blood outlet 6. The bubbles captured by the overbody 2 rise due to buoyancy and flow out from the bubble outlet 7 every time they collect in a certain amount at the upper part of the container body 1. The device shown in Fig. 2 consists of a cylindrical container 8 made of nylon, which has a blood inlet 9 in the tangential direction on the lower side, a blood outlet 10 in the center of the lower surface, and a bubble outlet 11 in the upper center. A cylindrical overbody 12 is accommodated so that the cylinder core becomes the vertical axis.
The upper open end of the cover plate 13 is closed. Due to the above mechanism, the blood flowing in from the blood inlet 9 flows upward while swirling around the overbody 12, and the swirling flow reduces the pressure caused by the blood flow when the blood passes through the overbody 12, resulting in a minute flow. This device avoids the passage of bubbles due to pressure, and also directs the microbubbles captured by the overbody 12 toward the bubble outlet 11, and its bubble separation function is the same as the device shown in FIG. 1 described above. There are two types for adults and children, each with a bubble removal function that corresponds to a predetermined blood flow rate. However, in the devices shown in Figures 1 and 2, if an overbody with a pore diameter of around 200 μm is used, not only will microbubbles easily pass through the overbody, but the air bubbles will be broken up into small pieces and pass through, resulting in safety issues.・Highly reliable. In the apparatus shown in FIG. 1, the ability to remove bubbles is extremely low when a large amount of air is mixed in at a large flow rate. Also, the pore diameter is 50μ
In the case of ~150μ overload, the removal of microbubbles is above 200μ
Since the overall performance is slightly better than that of the conventional arterial filter, a filter of 20 to 40μ is used as an arterial filter, with emphasis placed on the effect of removing foreign substances and aggregates. The disadvantage is that as the pressure increases, the pressure loss also increases. Furthermore, the device shown in FIG. 2 has a priming capacity of approximately 220 ml, which is disadvantageous in that it is large. FIG. 3 shows a conventional blood retention type blood bubble removal device. The device includes a container body 1 having a volume that reduces blood flow so that microbubbles can float.
There is a blood inlet 15 that penetrates the bottom of the container 14 and has an inner end located midway in the vertical direction inside the container 14.
A blood outlet 16 is provided at the bottom of the container 4, and an air bubble outlet 17 is provided at the top of the container 14. Therefore, the blood to be processed introduced into the container body 14 from the blood inlet 15 forms a gentle downward flow within the container body 14 and is allowed to rise due to the buoyancy of air bubbles in the blood, so that the treated blood is free of air bubbles. The air bubbles flowing out from the blood outlet 16 and rising inside the container body 14 are taken out from the air bubble outlet 17 every time a certain amount accumulates in the upper part. This device can separate and remove microbubbles to a certain extent by enlarging the container body 14 and making the container very large. However, this inevitably leads to an increase in the amount of extracorporeally circulating blood and fluid replacement, which leads to a decrease in the amount of blood remaining in the body, which has an adverse effect on the human body. Although it has been put into practical use, the priming volume is limited to about 250 to 400 ml, which cannot be said to be a sufficient volume to remove even the smallest bubbles.
Furthermore, miniaturization of the device itself has the disadvantage that it is difficult to put it into practical use due to its function of utilizing blood retention. FIG. 4a shows a conventional blood bubble removal device using an overbody/blood retention method, and FIG. 4b shows an overbody 22 housed in the internal space thereof. The device has a blood inlet 19 passing through the lower surface of the container body 18, a blood outlet 20 at the lower side of the container body 18, and an air bubble outlet 21 at the center of the upper part of the container body 18. has a nylon cylindrical overbody 22 connected to the inner end of the blood inlet 19, and a guide rod 23b is connected to the upper part of the support frame 23a and hangs down to the center of the inside of the overbody 22, The outer space of the overbody 22 is configured as a processing blood chamber 24 having a volume where the blood flow is small so that microbubbles can float. Thus, when the blood to be processed introduced from the blood inlet 19 rises around the guide rod 23b and passes through the overbody 22, air bubbles larger than the pore diameter of the overbody 22 are captured on the inner surface of the overbody, and the primary treated blood is Furthermore, in the processed blood chamber 24 outside the overbody 22, a very gentle downward flow is allowed to rise due to the buoyancy of the microbubbles that have passed through the overbody 22, resulting in secondary treated blood in which the removal of air bubbles is further promoted. Air bubbles flowing out from the outlet 20 and rising inside and outside the overbody 22 are taken out from the air bubble outlet 21 every time a certain amount accumulates in the upper part. However, in this device, even if the bubbles larger than the pore diameter are captured by the overbody 22, the surface of the overbody 22 is cylindrical as described above, and the guide rod 23b hangs down into the inner space of the overbody 22, so that the bubbles cannot be captured. As the internal volume of the inner space becomes smaller, the flow rate of the blood to be processed rising through the inner space increases. Therefore, the above-mentioned overbody 22
There is a risk that the air bubbles trapped in the blood flow will be raised by the blood flow, flow out from the upper opening of the overbody 22 with a downward flow toward the outside of the overbody 22, and head directly toward the blood outlet 20. 22
It also prevents the increase in buoyancy of microbubbles that have passed through. Therefore, a mechanism may be adopted that increases the internal volume of the blood processing chamber 24 to weaken the flow velocity and promote the rise of microbubbles due to the retention effect. This should be avoided because it leads to an increase in blood volume and fluid replacement volume, which produces unfavorable results for the human body.On the other hand, if the priming volume is made smaller than 190ml by miniaturizing the device, it will not be possible to remove microbubbles due to the retention effect. There is a drawback. () Purpose of the Invention The present invention was devised after intensive research in view of the above-mentioned points, and aims to remove air bubbles by the buoyancy increasing effect of air bubbles and the centrifugal separation effect caused by the difference in specific gravity between air bubbles and blood. In particular, compared to the conventional device mentioned above, the priming capacity can be made smaller, the device can be made more compact, the amount of extracorporeal circulating blood and fluid replacement can be reduced, and if the priming capacity is the same as the conventional device, the capacity can be improved, and microbubbles can be reduced. It is highly safe and reliable as it can remove the bubbles sufficiently, and since the burden of the excess body on bubble separation is small, even if the pore size of the excess body is increased, microbubbles can be removed, thereby reducing pressure loss due to the excess body. To provide a blood bubble removing device which can improve the performance of the device, reduce blood invasion such as destruction of platelets and red blood cells, and further eliminate almost all blood remaining in the device when returning blood after use. According to the present invention, this purpose is to include a container body, an overbody made of a porous material and provided to divide the container body into an upper space and a lower space, and a container body that communicates with the upper space. a liquid inlet provided in the container body to allow the blood to be processed to be introduced into the upper space as a swirling flow; a liquid outlet provided in the container body to communicate with the lower space and send out the processed blood passing through the body; In the blood bubble removal device, the blood bubble removal device includes an air bubble outlet provided in the main body so as to communicate with the upper center of the upper space and for removing air bubbles separated in the upper space, wherein the upper space formed by the container main body is By a blood bubble removing device characterized in that the upper side of the vertical cross-sectional shape passing through the center of the plane of the upper space has a flat shape with a horizontal or upward slope toward the center and a substantially circular planar shape. achieved. That is, the device for removing air bubbles in blood of the present invention collects the air bubbles in the upper center by circulating the blood containing air bubbles and using the buoyancy increasing effect of the air bubbles in the blood flow and the gas-liquid separation effect due to the difference in centrifugal force. It is intended to remove
In addition, the above-mentioned buoyancy increasing effect can also be achieved by ensuring that the lower part of the swirling flow, which is close to an overbody, is occupied by blood in which bubble removal has been sufficiently promoted, and by making the blood swirl like air bubbles in the blood immediately after introduction. and a part of the microbubbles that approach the overbody because the gas-liquid separation effect does not work sufficiently are collided with the overbody at a low angle, are repelled in a direction away from the overbody, and are collected in the upper center;
The amount of microbubbles smaller than the pore diameter of the overbody passing through the overbody is reduced. According to the device for removing bubbles in blood of the invention, the swirling flow of blood has a high flow velocity at the outer periphery and has a large gas-liquid separation effect immediately after the blood is introduced into the upper space from the liquid inlet, so that bubble separation progresses. The flow becomes slower toward the center, and the buoyancy of the bubbles increases significantly, resulting in a flow in which bubble separation progresses. Therefore, it is necessary to provide the liquid inlet at a distance from the overbody, and if the overbody faces the circumference of the swirling blood flow, the liquid inlet is provided above and away from the overbody. Therefore, the present invention provides an embodiment in which the container body has a shape that wraps around the circumferential portion of the upper space from above, below, and from the outside so that the circumferential portion of the upper space is not defined by the overbody. It is desirable to do so. () Specific description of the present invention (-1) Configuration A preferred embodiment of the blood bubble removal device of the present invention is shown in FIGS. 5 and 6. This blood bubble removal device includes a container main body 25, an overbody 28 that partitions the inside of the container main body 25 into an upper space (to-be-processed blood space) 26 and a lower space (processed blood space) 27, and an upper space in the container main body 25. It consists of a liquid inlet 29 and a bubble outlet 30 provided to communicate with the space, and a liquid outlet 31 provided in the container body 25 so as to communicate with the lower space 27. The container body 26 can be made of plastics such as polycarbonate, styrene, acrylic resin, AS resin, methyl methacrylate, butadiene, styrene, etc., but it is transparent so that air bubbles can be observed, and is biologically safe and strong. For safety reasons, it is preferable to make the upper space 2 from polycarbonate.
The circumferential portion of the upper space 26 is formed in a shape that wraps around the circumferential portion of the upper space 26 from above, below, and from the outside so that the circumferential portion of the upper space 26 is not defined by the overbody 28. The overbody 28 is made of a porous mesh made of plastic such as nylon, polyester, polypropylene, etc., and the pore size is selected to be larger than about 50 μm to prevent invasion of blood. The liquid inlet 29 is provided in the container body 25 so that the blood to be treated can be introduced from the circumference of the upper space 26 as a swirling flow. The bubble outlet 30 is provided in the container body 25 so as to communicate with the upper center of the upper space 26, and includes a bubble release valve 32. The liquid outlet 31 only needs to communicate with the lower space 27 and is provided in the container body 25 at an appropriate position relative to the liquid inlet 29 and the overbody 28.
The upper space 26 defined by the container body 25 has a flat shape in which an upper side portion of a vertical cross section passing through the center of the plane of the upper space 26 slopes upward toward the center. That is, the container body 25 passing through the upper space 26 defines the upper side of the upper space 26 with the inner surface of the container body through which floating bubbles can flow toward the bubble outlet 30. Further, the upper space 26 has a substantially circular planar shape. Therefore, the blood to be treated introduced from the upper space 26 and the liquid inlet 29 occupies the entire volume, forming a disk shape that can be used as a circulating flow. The volume of the upper space 26,
Each hole diameter of the liquid inlet 29 and the liquid outlet 31,
The area of the overbody 28 is appropriately determined in correlation with the amount of liquid to be treated so that the swirling flow of the blood to be treated is at a predetermined flow rate or less that does not prevent the increase in the buoyancy of air bubbles therein. Note that it is preferable to provide a bubble reservoir 42 in the upper part of the upper space 26, which can store a certain amount of bubbles. (-2) Effect The above-mentioned blood bubble removing device is preferably installed in the middle of the blood circuit connecting the oxygenator and the aorta in, for example, an artificial heart-lung machine. The blood bubble removing device is primed with a replacement fluid such as physiological saline or lactated Ringer's prior to introducing the blood to be processed. When the blood to be processed is introduced into the upper space 26 from the liquid inlet 29, the inside of the container body 25 is
The upper space 26 defined by
Since the blood to be treated occupies the entire volume of the upper space 26, it forms a swirling flow. Generally, when a liquid containing air bubbles in a closed container is subjected to a circulation flow, the difference in specific gravity between the liquid and air bubbles causes a difference in centrifugal force, and the air bubbles gather in the upper center part with the aid of buoyancy, causing the bubbles to self-destruct. to form a mass of air,
Therefore, the liquid flow contains fewer bubbles at the outer periphery of the circulating flow. However, in the blood bubble removing device of the present invention, the blood to be treated is introduced from the liquid inlet 29 into the upper space 26 in communication with the upper space 26, passes through the overbody 28, and flows out from the liquid outlet 31. The circulating flow contains many bubbles with no progress in bubble separation at its outer periphery, while the separation of blood and bubbles is accelerated toward the center. However, since the overbody 28 is located at the center of the lower layer of the swirling flow outside the outer periphery of the swirling flow, the overbody 28 is made of porous material with a pore diameter of 50μ or more to prevent invasion of blood. Even though the blood is made up of blood, only the blood for which bubble separation has been sufficiently promoted passes through the body 28 and flows into the lower space 27, where it flows into the liquid outlet 3.
It flows out from 1. On the other hand, the air bubbles in the blood to be processed introduced into the upper space 26 as a swirling flow are removed from the air bubble outlet 30 by opening the air bubble removal valve 32 every time a certain amount of air bubbles collects in the air bubble reservoir 42 . () Modifications of the present invention (-1) First modification In the blood bubble removal device shown in FIGS. 7 and 8, as the excess body 28 moves toward the center,
Unlike the above embodiment, the swirling speed of the separated air bubbles is unusually fast and the vortex of separated air bubbles extends in the direction of the blood outlet 31, so that the vortex of air bubbles is prevented from coming into contact with the overbody 28 as much as possible. This can be prevented, and the bubble separation function is the same as in the above embodiment. (-2) Second modification The blood bubble removal device shown in FIG.
The difference from the above embodiment is that 8 is provided in a spherical shape convex upward, but the bubble separation function is the same as in the above embodiment. (-3) Third modification The blood bubble removal device shown in FIG. The difference is that it slopes upward towards the center.
However, even if the upper surface portion 25a is horizontal toward the center, the bubbles can flow toward the bubble outlet 30 due to the centrifugal force that separates the blood and bubbles, so that the bubble separation function is different from that of the above embodiment. There is nothing to change. (-4) Fourth modification The blood bubble removal device shown in FIG.
8 is provided so as to define the circumference of the upper space 26, which is different from the above embodiment. In this case, the liquid inlet 29 is provided above the overbody 28 at a required distance so that the lower part of the outer periphery of the swirling blood flow in the upper space 26 is occupied by blood whose air bubbles have been sufficiently removed. The bubble separation function is the same as in the above embodiment. () Experimental results Figure 12 shows an experimental device for confirming the bubble removal ability of the blood bubble removal device of the present invention.
In Figure 2, 34 is a constant temperature bath whose water temperature is kept at 25°C, and 35 is a flask filled with a 35% glycerin solution, which has a viscosity of 2.5 centipoise, which corresponds to the hematocrit value (Hct) at 37°C. = blood cell volume/blood volume) corresponds to a blood viscosity of 35%. 36 is a filter that captures dust in the glycerin solution, and 37 is a roller pump that pumps the tube circuit to send the liquid at a rate of 4/min. 38 is a graduated syringe provided as a bubble injection means, 39 is an air trap for testing, 40
is an ultrasonic blood flow meter and the test air trap 3
It is installed immediately after 9. The ultrasonic blood flow meter 4
0 uses a 1935 model made by Sanei Sokki Co., Ltd. with a probe attached to a flat plate, a frequency of 5 MHz, a diagram can be recorded at a chart speed of 5 mm/s, and the sensitivity is such that it can detect bubbles with a diameter of about 20 μ. It's getting old. Reference numeral 41 denotes an observation air trap, which has a structure as shown in FIG. 42 is a cylinder
It has a capacity of 2,000 ml, and 43 and 44 are three-way stopcocks that have the function of changing the direction of the solution flowing in the circuit. 46 is an observation trap with a capacity of 1,000 ml, and a shielding plate 47 is provided inside. Due to the structure described above, the solution is instantaneously introduced into the cylinder 42 by operating the three-way stopcocks 43 and 44, and when the flow of the solution introduced into the cylinder 42 becomes stable, the rising speed of bubbles in the solution can be observed. The trap 46 collects air bubbles due to the retention effect, and the accumulated air bubbles can be measured at the graduated capillary section 48 at the upper end. This experiment not only confirmed the effectiveness of the present invention by comparing it with the conventional device mentioned at the beginning, but also confirmed that the device of the present invention can remove bubbles using a different method. This was done based on the recognition that even if the amount is small and the pore diameter of the superstructure is large, there is an excellent effect of increasing air removal ability. Therefore, the test air trap 3
9, the conventional apparatus shown in FIGS. 2, 3, and 4 and the apparatus of the present invention shown in FIG. 10 were replaced and used for experiments. Furthermore, with respect to the device of the present invention, a plurality of experiments were conducted by replacing the overbody with different hole diameters. The specific shape of each device and the dimensions that determine the priming capacity are shown in mm in the figure showing each device.
It is expressed only in numerical values.

[Table] Table 1 shows that the device of the present invention can effectively capture medium and small bubbles even though the priming capacity is smaller than that of the conventional device. It is also found that the device of the present invention can effectively capture medium and small bubbles even when the pore diameter of the overbody is around 260 μm. FIGS. 14 and 15 show the experimental apparatus shown in FIG. 12, the conventional device shown in FIG. 4 and the device of the present invention shown in FIG. The graphs are diagrams obtained using the ultrasonic blood flow meter 40 after experiments were conducted on each of the two, with the air volume injected by the bubble injection means 22 being 30 ml. Both diagrams show that when air is injected in both devices, the needle swings significantly, and the magnitude of the amplitude is almost the same for both devices, but the length of the amplitude disturbance is much greater in the conventional device than in the device of the present invention. It shows that it is a long time. Note that in both diagrams, the disturbance of the needle before air injection and after the amplitude disturbance has subsided is considered to be noise caused by air bubbles or impurities in the solution used in the experiment. It can be seen from both diagrams that the device of the present invention separates and removes air bubbles from the blood quickly, and the outflow of air bubbles is observed over a relatively long period of time compared to the conventional device. This difference is due to the fact that in the device of the present invention, air bubbles in the blood are actively transferred to the bubble outlet by the action of centrifugal force as the blood becomes a circulation flow, whereas in the conventional device, air bubbles in the blood are actively transferred to the bubble outlet due to the action of centrifugal force. Air bubbles are removed by trapping air bubbles and retaining and trapping microbubbles passing through the overbody, and when air bubbles are captured in the overbody, they may pass through the upper part of the overbody again and the air bubbles may pass through the upper part of the overbody again. The microbubbles passing through the liquid have extremely low buoyancy, and many of them do not head toward the bubble outlet, but slowly head toward the liquid outlet along with the downward blood flow, so to speak, the bubbles in the blood passively move toward the bubble outlet. It is assumed that. Figures 16, 17, and 18 show the experimental setup shown in Figure 12, in which an integral measuring device is connected to the ultrasonic blood flow meter, and the needle deflection of the ultrasonic blood flow meter is measured. This is a diagram recording the respective integral values. In each figure, the diagram below records the deflection of the needle of the ultrasonic blood flow meter.
The upper diagram is an integral curve corresponding to the deflection of the needle. 16 shows the case where the test air trap 39 is the conventional device shown in FIG. 2, FIG. 17 shows the case where the conventional device shown in FIG.
FIG. 8 shows a case where the apparatus of the present invention shown in FIG. 10 is used. In this experiment, in the experimental apparatus shown in FIG. 12, the probe of the ultrasonic blood flow meter was connected to a stainless steel plate wrapped around the outside of a pipe made of acrylic resin with an inner diameter of 6 mm. This is to eliminate blood flow waves so that only waves for air bubbles can be observed. The conditions for this experiment were as follows: The test solution used was bovine blood diluted with physiological saline to give an Hct of 35% using heparin (5000 units/) and ACD solution (50 ml/) as anticoagulants, and kept at 37°C. The amount of air injected from the air bubble injection means 38 was 10 ml. In Figures 16, 17, and 18, a perpendicular line is drawn from the apex of each wave of the upper integral curve to the horizontal axis coordinate, and the area surrounded by this perpendicular line, the integral curve, and the horizontal axis coordinate is This is the amount of bubbles that could not be captured by the test air trap 39 of the experimental apparatus shown in FIG. 12 and was measured by an integral measuring device connected to the ultrasonic blood flow meter 40. In these three experiments, it was found that the wave height of the integral curve in FIG. 18 was small and the wave convergence was the fastest. Therefore, the blood bubble removal device shown in FIG. 12 according to the present invention is the one shown in FIG. It was confirmed that the bubble removal ability was higher than that of the conventional device shown in FIG. 4 and FIG. () Effects As explained above, in the blood bubble removal device of the present invention, the inside of the container body is divided into an upper space and a lower space by the overfill, and there is a liquid inlet that communicates tangentially with the circumference of the upper space. In the case where there is a bubble outlet in the upper center of the upper space and a liquid outlet communicating with the lower space, the upper part of the vertical cross section passing through the horizontal center of the upper space defined by the container body is horizontally directed toward the center. It has a flat shape with an upward slope and a circular planar shape. Therefore, the device for removing bubbles in blood of the present invention can introduce the blood to be processed into the upper space from the liquid inlet as a swirling flow with the longest path, and the air bubbles in the blood can be removed from the upper part of the upper space by buoyancy and centrifugation. The bubbles can be actively collected in the center and discharged from the bubble outlet, and the lower layer of the blood to be processed near the superbodies filling the upper space can be actively promoted to bubble separation, and furthermore, the superbodies themselves can be The trapping of air bubbles by this function has the effect that the treated blood that passes through the body, passes through the lower space, and reaches the liquid outlet is blood from which air bubbles have been sufficiently removed. According to the device of the present invention, air bubbles are actively collected in the upper center using swirling flow and buoyancy to trap and remove them.In particular, the buoyancy is extremely small and is easily affected by the flow of blood. It has been fully confirmed by the above-mentioned experiment that it can effectively capture and remove even easily-prone microbubbles.
This device has better bubble removal ability than conventional devices. Therefore, the blood bubble removal device of the present invention can effectively remove even minute bubbles from the blood to be processed, thereby making it possible to extremely reduce the amount of bubbles passing through the blood, thereby improving the safety and reliability of the device. In addition, the device for removing air bubbles in blood of the present invention actively collects and removes air bubbles in the upper center by circulating the blood to be processed, so that the process can be substantially lengthened, compared to conventional devices. The experiment described above has confirmed that it is possible to downsize the device so that the priming volume is small. If the inventive device is made to have the same priming capacity as the conventional device without being downsized, the processing capacity will be improved compared to the conventional device, and the removal of microbubbles will be further promoted than when the device is downsized. Further, the blood bubble removal device of the present invention uses the blood to be treated as a swirling flow and actively collects the bubbles in the blood at the upper center by buoyancy and centrifugation.
The lower part of the swirling flow of blood in the upper space near the excess body is occupied by blood for which bubble removal has been sufficiently promoted. Even if you use an overbody consisting of a porous body with inner and outer pore diameters,
Microbubbles of 0.1 mm or less can be removed effectively, and the safety and reliability of the device will not be compromised, and if a pore diameter of 260μ is used, blood invasion such as destruction of platelets and red blood cells can be prevented. In addition, there is no fear, and the pressure loss in the overbody is significantly reduced compared to the conventional method, which has the effect of improving the performance of the device. In addition, as an embodiment of the present invention, when the container body has a shape that envelops the circumferential part of the upper space from above, below, and from the outside so that the circumferential part of the upper space is not defined by the overbody, the overbody is a bubble of blood swirling flow. Facing the central lower layer where removal has been sufficiently promoted, the passage of microbubbles through the body is reduced and the bubble removal ability is further increased.The liquid inlet is moved closer to the body to make the upper space even thinner, which reduces the priming capacity and reduces the device size. It has the effect of being able to be made smaller.

[Brief explanation of the drawing]

FIGS. 1 and 2 are longitudinal sectional front views of a conventional overbody type blood bubble removal device, FIG. 3 is a longitudinal sectional front view of a conventional blood retention type blood bubble removal device, and FIG. 4 a is a conventional blood bubble removal device. Fig. 4b is a longitudinal sectional front view of a blood bubble removal device of a combination type of overbody type and blood retention type;
FIG. 5 is a longitudinal sectional front view of a blood bubble removal device according to a preferred embodiment of the present invention, and FIG. 6 is the same as above.
7 is a longitudinal sectional front view of a blood bubble removal device according to a first modification of the present invention, FIG. 8 is a cross-sectional view of the same as above, and FIGS. FIG. 1 is a vertical front view of the blood bubble removal device according to the second, third and fourth modified examples of the invention;
FIG. 2 is an experimental device for confirming the technical effects of the present invention, and FIG. 13 is a vertical sectional view of an observation air trap prototyped for use in the same device. FIGS. 14 and 15 are diagrams obtained using an ultrasonic blood flow meter when experiments were conducted on the bubble removal effect using the conventional device and the device of the present invention using the experimental device shown in FIG. 12. Figures 16, 17 and 18 are 12
1 is a diagram obtained by an ultrasonic blood flow meter and an integral measuring device connected thereto for a conventional device and a device of the present invention in an experiment using the experimental device shown in the figure. 25... Container body, 26... Upper space, 27...
... lower space, 28 ... overbody, 29 ... liquid inlet,
30...bubble outlet, 31...liquid outlet.

Claims (1)

[Claims] 1. A container body, a porous body provided to divide the container body into an upper space and a lower space, and a container body configured to communicate with the upper space. A liquid inlet is provided to introduce the liquid to be treated into the upper space as a swirling flow with respect to the overbody, and a liquid inlet is provided in the container body so as to communicate with the lower space and sends out the treated blood passing through the overbody. A blood bubble removal device comprising a liquid outlet and a bubble outlet provided in the container body so as to communicate with the upper center of the upper space and for removing air bubbles separated in the upper space, The upper space in which the blood is stored has a flat shape in which an upper side portion of a vertical cross-sectional shape passing through the center of the plane of the upper space is horizontal or slopes upward toward the center, and has a substantially circular planar shape. Air bubble remover. 2. Claim 1, wherein the container body has a shape that wraps around the circumferential portion of the upper space from above, below, and from the outside so that the circumferential portion of the upper space is not defined by the overbody. The blood bubble removal device described.