JPS6145770A - Blood storage tank - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (16) Background of the Invention (Technical Field) The present invention relates to a blood reservoir (cardiosomal reservoir) used in an artificial heart-lung circuit during extracorporeal circulation associated with open heart surgery.

(Prior art and its problems) In an artificial heart-lung circuit, as illustrated in FIG. 1, blood removed from the patient's vena cava passes through a blood removal line 1
The blood from the surgical duck passes from the suction line 2 and the pump 3 through the blood reservoir 4 and the line 5, enters the venous reservoir 7 housed in the volume regulating means 6, and is further sent to the oxygenator 9 with a heat exchanger by the pump 8. , where the oxygenated blood is configured to be returned to the patient's body via a blood supply line IO.

By the way, in addition to the functions of defoaming and storing blood sucked into surgical instruments such as the thoracic cavity and heart cavity, the blood reservoir currently has the function of defoaming and storing blood that is aspirated through surgical instruments such as the thoracic cavity and heart cavity. Products that incorporate a filter to filter out foreign substances such as microaggregates and are configured to perform the three important functions of filtration, defoaming, and blood storage have become commercially available. However, it has been pointed out that the blood reservoirs currently in use have the following various problems in the three functions mentioned above.

(1) Problems with the efficiency of the filter When blood containing many foreign substances such as tissues and microaggregates is passed through the filter, the filter tends to become clogged quickly before it is used effectively. Furthermore, in the case of a pleated filter, a lumen is created due to the cylindrical arrangement of the filter, and therefore blood pools in this lumen, making it difficult to accurately determine the amount of blood in the blood reservoir. Therefore, there is a difference between the scale mark marked on the housing of the blood reservoir and the actual amount of blood stored, resulting in the problem that the actual amount of blood fluid cannot be read when necessary. Furthermore, filter performance and the ability to quickly separate blood and bubbles within the filter conflict, and it is difficult to find a balance between them.

(2) Defoaming function -1- Problem Blood entering the blood storage tank is filtered and defoamed by a filter and an antifoaming agent, and then stored in the housing. In a structure in which outflowing blood (or priming liquid) is once defoamed and drips onto the blood surface where the blood is stored, bubbles will occur again, which is undesirable. In such a case, blood containing microbubbles is also sent to the patient, and there is a risk of brain damage due to peripheral blood vessel occlusion.

There are some structures that avoid the above phenomenon by bringing the filtration and defoaming member into contact with the bottom of the housing, but in this type of structure,
An air block phenomenon in which the air in the blood discharge boat at the bottom of the housing and the tube connected thereto cannot be discharged and is left behind tends to occur. For a membrane lung using a closed venous reservoir, this poses a significant risk of air contamination into the venous reservoir, oxygenator, and patient. Air block phenomenon is when the blood surface inside the tube connected to the blood outflow port is clamped, and when a large amount of blood flows in, the air cannot be discharged and some of the blood remains inside the tube. It means the phenomenon of being put away.

In addition, in a blood storage tank with a built-in filter, due to the resistance of the filter, which has recently become more sophisticated, it is necessary to have a structure that defoams after filtration. When doing so, positive pressure filtration is used. In positive pressure filtration, as the blood flow increases, the processing capacity of the defoaming member is exceeded, and positive pressure air squirts blood out of the filter.
As a result of producing bubbles in the blood, subsequent defoaming is likely to be disadvantageous. In such a case, the pressure increase in the filter is also large, which tends to reduce filter performance. In order to avoid this, some products have adopted a cyclone type air separation structure at the blood inlet, but this cannot be done when a large amount of air is mixed in, which tends to cause a pressure increase, and results in considerably poor defoaming performance. I'm inviting you.

In addition, even if the structure has the advantage of separating the filtration/defoaming section and the blood storage section, the blood once defoamed in the filtration/defoaming section is transferred from the filtration/defoaming section to the blood storage section via the guide section between them. During the transition, there remained the problem that foam would form again between the filtration and defoaming section and the guide section or between the guide section and the bottom of the housing.

(3) Problem 2: Blood storage function There is also a problem with the shape and structure of the housing in terms of blood storage function. In terms of mold production, it is convenient for the housing to produce flanged halves and bond them together at the middle. However, with such a structure, there is a possibility of blood leakage at the bonded portion, and at the same time, it is troublesome to display the liquid volume scale on the label, and the display of the stored blood volume at the flange part is likely to be inaccurate. Furthermore, depending on the case of open heart surgery, blood volume is often measured through the vent line in order to ascertain the status of circulatory abnormalities and valve insufficiency. In other words, the heart is in an ischemic state, but if there is abnormal pulmonary venous return, blood accumulates in the left ventricle, and the degree of abnormality can be understood from the amount. Also, if there is caval valve insufficiency, this is also determined by the amount of blood stored in the left ventricle. That is, in order to measure these quantities through the vent line, fine scale display is required. Therefore, the shape of the housing bottom and the blood outflow port is required to be such that the blood volume can be easily read.

Further, even if the area of the filter is the same, it greatly affects the above-mentioned separation function of the filter between blood and bubbles, and the longer the filter, the better the separation function. For this reason,
Many use long filters that reach near the bottom of the housing. However, in these types of blood reservoirs, the contact time between the constituent members and the blood is long, which is undesirable due to the fact that complement activation and silicone desorption, which are currently attracting attention, are highly problematic. A typical example of a filter that reaches near the bottom of the housing is USP 4,1.
64,468, 4,209,193, etc.

II. OBJECTS OF THE INVENTION The present invention has been made in view of the above-mentioned current situation, and its purpose is to separate the filtration and defoaming section from the blood storage section so that blood comes into contact with foreign matter in the filtration and defoaming section of the blood storage tank. The time required for this is kept short, that is, only the transit time, and the blood once defoamed in the filtration and defoaming section is foamed again between the filtration and defoaming section and the guide section or between the guide section and the blood storage tank. We are trying to provide a blood reservoir configured so that it does not occur.

(19) Structure of the Invention That is, the present invention comprises a hollow body having a blood inlet at the top and a blood outlet at the bottom, a filtration and defoaming part provided above the hollow body, and further the filtration and defoaming part. part to flow 11j
A guide part for guiding blood to the bottom of the hollow body is provided in a shape converging from the filtration and defoaming part toward the bottom of the hollow body, and a blood outflow part of the filtration and defoaming part and a blood receiving part of the guide part are provided. The distance between the guide parts is equal to or smaller than the length of the blood droplet, and at the distal end of the guide part, the blood flow flowing on the converging inner surface of the guide part is divided into rivulets. The purpose of this invention is to provide a blood storage tank.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The blood reservoir of the present invention will be described in detail below with reference to preferred embodiments shown in the accompanying drawings.

FIG. 2 is a partial cross-sectional side view of the blood storage tank 20 of the present invention with a part broken and removed to make the inside visible. The blood flows from there to the bottom of the housing or to the blood storage area.
You can clearly see that it is designed to guide you towards. l＼Using 21 is a hard transparent body made of a hard plastic material such as polycarbonate, acrylic-styrene copolymer, polyester, polyamide, polyvinyl chloride, acrylic-butadiene-styrene copolymer, etc., preferably by integral molding. be done.

The top of the housing 21 is closed by an upper lid 22 and a housing extension 23, and a robot 24 containing aspirator blood is closed at the top of the housing 21. A filter-through infusion port 25, a rapid infusion port 26 are provided, and an air vent port 27 is provided on the housing extension 23.

The body of the housing 21 is approximately cylindrical and hollow. The bottom of the housing 21 has an eccentrically formed blood outlet 2.
9, and a medium-high support portion 32 for supporting the filtering and defoaming member 30 and the deflector 31 is formed in the center thereof.

It is better to construct the housing 21 in half in terms of mold production, but from the viewpoint of blood leakage, scales, labels, etc.
It is preferable to mold it seamlessly as a single piece except for the top part. In particular, it is necessary to prevent blood from stagnation at the bottom, and it is better not to have adhesive parts.If the blood outlet 29 is provided at the bottom of the housing 21, it is better to provide the blood outlet 29 at the center of the bottom of the housing 21, so that the scale, blood volume, etc. can be easily seen. Therefore, it is preferable to provide the housing 21 eccentrically near the outer periphery of the bottom of the housing 21. Furthermore, depending on the case of open heart surgery, it may be necessary to know the exact amount of blood, even if it is small, so it is preferable that the shape of the blood outflow port 29 is funnel-shaped with a smooth curved surface. In particular, if the scale has a convex shape such as a hemispherical shape, the scale can be easily read.

In this way, when blood flows into the venous reservoir through the tube connected to the funnel-shaped blood outflow port having a smooth curved surface, the blood flows along the blood outflow port 29 and the wall surface of the tube. -The air block phenomenon, which is the problem mentioned above, does not occur. This also applies if the blood level rises or falls at the blood outlet due to the vertical movement of the blood reservoir during adjustment operations to optimize the body's blood volume, which is constantly monitored, or fluctuations in the blood inflow from the surgical instrument. , the air block phenomenon is likewise prevented.

The filtration and defoaming member 30 disposed in the upper part of the housing 21 is connected to the upper lid 2 together with the guide member 28 below.
It is supported between an upper support body 33 extending from 2 and a mid-high support part 32. The filtering and defoaming member 30 has various functional elements concentrically arranged outward from the center, and sequentially distributes air-mixed blood introduced into the center evenly, separates blood and bubbles, After filtering and defoaming, the defoamed blood is transferred to the guide member 2 at the bottom of the housing without generating bubbles again.
8, the blood is stored in the blood storage section (2) or the bottom of the housing.

The filtration and defoaming member 30 has a filter 35 having a lumen 34 and a defoaming member 36 around its outer periphery, and the filter 35 has an adhesive 38 between an upper support 33 and a lower support 37.
The defoaming member 36 is fitted onto the filter 35 and supported by the lower support 37 . The upper support body 33 is
A cylindrical body 40 that hangs downward by a length shorter than the length of the filter is provided in the lumen 34 formed by the filter 35, and an annular gap 41 is defined between the filter 35 and the cylindrical body 40. Since there is a cylindrical body in this gap, blood directly enters and filters out. Therefore, the part of the filter corresponding to the gap 41 does not get wet, and from this part, the bubble air separated from the blood flows to the filter 35 and the defoaming member 36. and is discharged via a vent boat 27.

The lower support 37 has a lumen 3 formed by a filter 35.
4 has a hollow member 42 standing up on one side, and the lower part 44 of the hollow member 42 is in close contact with the filter 35, but the upper part 44 is in close contact with the filter 35.
3 is a substantially upper support member 33 whose diameter is reduced and extends upwardly within the cylindrical body 40.
Extend to the position.

The hollow member 42 and the cylindrical body 40 are preferably arranged concentrically with the filtering and defoaming member 3o, and the gap 45 between the hollow member 42 and the cylindrical body 40 defines the blood flow path. The head of the upper portion 44 of the hollow member 42 may be rounded to provide even blood distribution.

Conventionally, this blood distribution hollow member 42 was not disposed inside the filter 35 to form a lumen, and there was a problem in that blood whose amount could not be measured was accumulated in this lumen, but in the present invention, ,
The placement of the blood distribution hollow member 42 into the lumen 34 of the filter 35 to a considerable height position eliminates unnecessary lumens and improves the even distribution of blood into the filter 35 and the cylindrical body 4.
Blood and bubble separation gap 4 between 0 and filter 35
By forming No. 1, the filtering surface can be used effectively, and channeling as in the conventional case can no longer occur. The constituent materials of the blood distribution hollow member 42 include polycarbonate, acrylic-styrene copolymer, polyamide, polyester, polyvinyl chloride, acrylic-butadiene-styrene copolymer, and polycarbonate, which can define the diameter of the inner cavity 34 of the filter 35. Hard plastics such as propopylene are preferred.

A filter 35 disposed around the blood distribution hollow member 42
Although there are various types of filters, pleated filters are preferred for compactness and weight reduction, even if a screen type with a mesh with a pore diameter of about 20mm or a depth type with an adsorption effect are used. It is preferable that the filter 35 is not limited to a pleated type, and that it contacts the blood distribution hollow member 42 at equal intervals, with a certain amount of space formed therebetween. Filter 35 and blood distribution hollow member 4
2 at equal intervals can increase the effective area of the filter. Furthermore, the space formed between the filter 35 and the blood distribution hollow member 42 is intended to provide a storage space for substances that impede effective use of the filter, such as clogging and channeling caused by foreign substances such as tissues and microaggregates. It's for a reason.

In a blood storage tank with a built-in filter, blood is filtered under positive pressure, but as the blood flow rate increases, the processing capacity decreases, and the blood is ejected from the filter due to positive pressure, generating bubbles, which are then defoamed. As mentioned above, it may be disadvantageous. To prevent this, it is best to treat the filter with an antifoaming agent in advance. As an antifoaming agent,
-at is preferably a defoamer silicone (contoured type mixed with silica, oil type), etc., and the filter constituent material is preferably nylon, polyester, polypropylene, etc. The filter is preferably made of mesh or nonwoven fabric. By attaching an antifoaming agent to the filter, when blood comes into contact with the filter, bubbles are defoamed and blood and air are separated, which prevents the pressure from rising due to the filter and at the same time improves the filtration of the filter. Sexual pilgrimage is maintained.

The defoaming member 36 on the outer periphery of the filter 35 is for defoaming the blood that has been filtered or defoamed by the filter 35 on the second flow side. , coated with the antifoaming agent mentioned above. The defoaming member 36 is wrapped in a tricot-like bag 46.

Further, in the blood storage tank of the present invention, the filtration and defoaming section I is biased toward the upper part of the hollow housing. As mentioned above, this is to avoid contact with foreign matter as much as possible by not dipping the blood into the filter 35 or antifoaming member 36 as in the conventional case.This is currently attracting attention. Complement activation L (a type of tannin complement that is present in animal serum and plays an important enzymatic role when antigen-antibody reactions occur in vivo) is activated. Cell membrane damage, the body's defense mechanism against infection, and inflammatory response are impaired. In addition, due to activation, complement is consumed, temporarily lowering the body's immune system and increasing the risk of infection, etc.), and the release of silicone. The filter 35 and the defoaming member 36 are
To provide a scale that can reduce dead polyum in blood and accurately grasp the amount of blood at the time of blood return.

In order to achieve such a function, the present invention requires that the blood filtered and defoamed in the filtration and defoaming section I be filtered and defoamed in the filtration and defoaming section I.
A guide member 28 is provided at the bottom of the filtration and defoaming member 30 so that the blood can be guided again to the blood outflow port 29 at the bottom of the filter 1 without generating a pull.The guide member 28 is a funnel-shaped deflector 3
1 is preferable.

The deflector 31 converges to be supported on a lip 39 on a raised support 32 in the center of the bottom of the housing 21 . The details of the deflector 31 will be explained in detail later with reference to FIGS. 3 and 4. This deflector 31 is connected to the housing 21
It is preferable to avoid opening the flow path by contacting the body and the bottom adjacent to the body. This is because if the deflector 31 and the housing come into contact as described above, when the blood level is below the contact point, the contact point is likely to be mistaken for the blood level, which may lead to a misunderstanding by the operator.

Also, since blood is constantly flowing over the deflector, and if the deflector is made of a transparent material, it tends to be difficult to read the blood level, so the deflector should be made of something that does not give the impression of blood color, or is made of an opaque or colored material. It is preferable to do so.

In FIGS. 3 and 4, blood filtered and defoamed in the filtration and defoaming section I is shown between the filtration and defoaming member 30 and the deflector 31 and between the deflector 31 and the mid-high support part 32 at the bottom of the housing 21. A preferred configuration example of the deflector 31 that prevents re-foaming is shown below.

The deflector 31 has a converging funnel shape, and allows the filtered and defoamed blood to flow down onto its inner surface without re-foaming.

As shown in FIG. 4, the deflector 31 has a substantially frustoconical body 50, the top of which constitutes a blood receiving portion by an overhang 51 and a substantially horizontal step 52. This blood receiving portion is a portion that directly receives blood flowing out from the defoaming member 36 wrapped in the tricot bag 46 of the filtration and defoaming member. If blood from the defoaming member 36 drips into this area, the impact will cause foaming to occur again.

Therefore, in the present invention, the distance between the outer peripheral end of the foam-defoaming member 36 and the horizontal step portion 52 is made smaller than the vertical size of the blood droplet from the tricot bag 46 that encloses the foam-defoaming member 36. This prevents a phenomenon in which blood forms droplets from the defoaming member 36 and drips. However, if the distance between the antifoaming member 36 and the horizontal step portion 52 of the deflector 31 is made too small, foaming may occur because the wave path of the blood is narrow when a large amount of blood flows out.

Therefore, it is preferable that the distance between the outer peripheral edge of the tricot bag 46 enclosing the defoaming member 36 and the horizontal step of the deflector 31 be equal to or slightly smaller than the vertical length of the blood droplet. . Furthermore, it is preferable to form a plurality of ribs 53 as guide portions that guide blood to the horizontal step portion 52 without dripping. An example of its configuration is shown in FIG.

Further, it is preferable that the blood defoamed by the defoaming member 36 flows out from the outer peripheral end of the tricot bag 46 that encloses the blood. For this purpose, it is preferable that the central part of the tricot bag 46 enclosing the defoaming member 36 be pushed up and tilted toward the outer periphery.

In the present invention, in order to achieve this objective, three or more ribs 56 are preferably formed on the horizontal step portion 52 at equal angular intervals.

Tricot I/bag 46 that wraps the defoaming member 36 in this way
The blood that has flowed out from the outer circumferential edge of the deflector 31 into the horizontal stepped portion 52'' of the deflector 31 without foaming flows down the inner surface of the inclined body portion 50 of the deflector 31 along its wall, and finally flows down the wall of the inclined body portion 50 of the deflector 31. It flows out from the end onto the mid-height support part 32 without dripping in the same way as above.

It is preferable to provide a plurality of guide plates 54 between the body portion 50 of the deflector 31 and form a plurality of blood flow paths to disperse the blood into many flows and to minimize the chances of foaming. Furthermore, in addition to the guide plate 54, ribs 55 are disposed at the distal end of the body 50, preferably evenly angularly, so that the blood flow is dispersed into finer flows and the outflow pressure or outflow from the body 50 is increased. Avoid foaming due to the film that may form. A preferred example of the rib 55 is shown in FIG.

The ribs 55 formed at the end of the body 50 are preferably equally spaced, and in that case, the rib shape is such that the outlet at the end of the deflector has an area that ensures rapid flow even in the face of ocean flow. , and a number of ribs configured to have a spacing that does not create a blood bubble film. The number of ribs 55 is preferably at least three. As a result of various tests, it has been confirmed that when the number of ribs 55 is less than 8, the flow becomes non-uniform, or the bubble film of blood breaks and microbubbles are generated.

The defoamed blood that has exited the filtering and defoaming member 30 passes through the trough-like passage 47 of the deflector 31 and forms a gentle flow, so that the invasion of the blood is small and no bubbles are generated again.

Now, in a closed system, the amount of blood stored at the bottom of the housing, which does not come into contact with the filtration/defoaming part, is always between 300 and 500.
Because the first blood storage is forced, the lower limit is at least 5.
1,000 m is required, and when there is a large
Since more than ml of coolant is required, the upper limit is 2500cm.
First place is necessary.

The deflector 31 is for guiding the filtered and defoamed blood to the bottom of the hollow housing 21 without foaming again. Most conventional deflectors are configured to allow blood flow to flow above the blood stored in the lower part of the housing, and as mentioned above, it is easy to mistake the level of blood on the deflector and the level of the stored blood.

In the present invention, the above-mentioned example is shown as the deflector 31 that guides the filtered and defoamed blood from the filtration and defoaming member 30 to the bottom of the hollow housing 21. However, as another configuration example, the housing 21 does not necessarily have an inclined bottom. The blood processed by the filtration and defoaming part 30 is guided by the deflector 31 that converges toward the blood outflow port 29 located in the center of the housing 21, which does not need to have a mid-height support part 32. You can also do it. In this case as well, the blood flows down on the inner surface of the deflector 31, but the color of the blood is not visible unlike in the conventional case where the blood flows down the outer surface, so the liquid level of the blood can be accurately visually observed, and the amount of blood stored can be checked. Measurement becomes easier. Furthermore, it is even more effective if the deflector 31 is made of an opaque or colored material.

Note that the hollow housing 21, the cylindrical body 40, and the hollow member 42
has been described as having a cylindrical shape, but it can be formed into any other suitable shape such as a polygonal column or irregular cross-sectional shape, and it goes without saying that the hollow member may be a solid body.

(1) Specific Functions of the Invention The filtration, defoaming, and blood storage functions when using the blood storage tank of the present invention will be explained.

The blood reservoir is constructed and used as shown in FIG. Bubble mixed blood sucked from a surgical site such as the cardiothoracic cavity during open-heart surgery or the like falls onto the upper part 43 of the hollow member 42 through the blood inlet port 24. After passing through the blood flow path between the upper part 44 of the hollow member 42 and the cylindrical body 40, the blood directly flows to the filter 3.
5, and contacts the filter 35 for the first time at the lower part 44 of the hollow member 42. The blood passes through the portion from the upper part 43 to the lower part 44 of the hollow member 42, and by increasing the contact area of the member with the bubble-mixed blood before contacting the filter 35, the bubbles and the blood are separated. Since a gap 41 is provided between the filter 35 and the cylindrical body 40, the separated A-pull collects in that area, is swept away by the blood, and does not pass through the filter.

As shown by the solid line showing the flow of blood and the dotted line showing the flow of bubbles, the bubbles are separated from the blood and gather toward the gap 41.
Filter 3 with or without antifoaming agent
5 and the defoaming member 36, the air is discharged to the outside through the vent port 27, accumulates in the filter lumen 34, increases the internal pressure, and together with the pressure from positive pressure filtration, bubbles are eliminated. There is no possibility that the blood will be squirted out of the filter 35 together with the blood.

In addition, the amount of blood conventionally stored in the filter lumen 34 is reduced due to the presence of the hollow member 42 and the rapid and effective separation of blood and bubbles as described above, and the amount of blood in the blood reservoir can be accurately determined. I am now able to understand.

The filter 35 disposed on the outer periphery of the hollow member 42 is evenly distributed in the hollow member 42 , and the filter 35 is arranged on the outer periphery of the hollow member 42 .
0, the bubbles effectively filter out foreign substances such as tissues and microaggregates contained in the separated blood or transfused blood from the blood.

In this manner, the blood filtered or filtered and defoamed by the filter 35 is completely defoamed while passing through the defoaming member 36, and the blood oozes out of the defoaming member 36 from the tricot bag 46. The leached blood flows out from the outer peripheral edge of the tricot bag 46 onto the horizontal step 52 of the deflector 31 without dripping, and this action is prevented by the ribs 53 formed on the horizontal step 52 from the center of the tricot bag 46. This is facilitated by the fact that it is pushed up and its outer periphery is inclined. The blood that has flowed out onto the horizontal stepped portion 52 of the deflector 31 without dripping gently flows down the trough-like passage formed by the guide plate 54 of the deflector 31 and reaches the end of the body portion 50. A large number of ribs 55 are formed at the end of the body 50, and the blood flow is further resulfurized, and at the same time, the formation of a bubble film at the end of the ribs is prevented, so that the blood flow is not generated again in the blood storage space 48. Inflow. The blood in the blood storage space 48 forms a swirl flow around the middle and high support part 32 through the inclined bottom part of the housing 21 and reaches the venous reservoir 7 through the blood outlet 29 and the retube 5. This also applies to the configuration example shown in FIG.

In addition, if the blood outflow "J29" is not formed at the center of the bottom of the housing 21, but is formed near the outer peripheral edge, and its shape is a bulge made of a smooth curved surface such as a spherical shape, it is possible to Even a small amount of blood can be accurately and easily read by the scale attached to the blood outflow port 29. In this way, a swirling flow is formed in the exuded blood, and a smooth flow is also ensured at the blood outflow port 29. By configuring so that the
This eliminates any risk of bubbles circulating through the venous reservoir into the patient's body.

The blood storage capacity of the blood storage space 48 at the bottom of the housing is 500 to 2
There are 500 intestines, and since the filter 35 and antifoaming member 36 are not constantly immersed in the stored blood, there is little risk of complement activation or silicone elution, and the blood storage capacity is sufficient even in emergencies.

(2) Specific Effects of the Invention The blood reservoir of the present invention provides many advantages over conventional ones, as listed below.

(1) Since the i1i hyper-defoaming part and the blood storage part are completely separated, the blood collection does not constantly immerse foreign substances such as the filtration member and the defoaming member, so complement activation, silicone elution, etc. There is very little fear of

(2) By providing a cylindrical body and a hollow member concentrically in the inner cavity of the filter and forming a gap between the cylindrical body and the filter, separation of blood and bubbles is facilitated, and the separated bubbles are transferred to the cylindrical body. Since air can escape through the protected part of the filter that is wetted by the body, the bubbles no longer increase the internal pressure and are forced out of the filter together with the blood under the pressure of positive pressure filtration, as was the case in the past.

(3) Since the distance between the outer periphery of the tricot bag enclosing the defoaming member and the horizontal step of the deflector is smaller than the length of the blood droplet, there is no risk of blood dripping onto the deflector and foaming. That's no longer the case.

Further, since the tricot bag is configured to be pushed up at the center and tilted downward toward the outer periphery, blood flows out only from the outer periphery.

(4) A large number of ribs are provided at the end of the deflector to divide the flowing blood into many blood trickles.
There is no possibility of blood dripping from the end of the deflector to the bottom of the housing and causing foaming.

[Brief explanation of drawings]

FIG. 1 is a diagrammatic perspective view of an example of an artificial heart-lung circuit, FIG. 2 is a partially sectional side view of a preferred embodiment of the blood reservoir of the present invention, and FIG. 3 is a plan view of a deflector used in the blood reservoir of the present invention. , FIG. 4 is a sectional view taken along line 1 to 2 in FIG. 3, and FIGS. 5 and 6 are side views of preferred examples of ribs formed at the upper and lower parts of the deflector, respectively. Explanation of symbols 1...Blood removal line, 2...Soccer line, 3.8
...Pump, 4.Blood reservoir, 5.Line, 6.
...Capacity regulating means, 7. Venous reservoir, 9. Oxygenator with heat exchanger, 10. Blood supply line, 20. Blood storage tank of the present invention, 21. Housing, 22.・First
Upper lid, 23... Second upper lid, 24... Suction blood flow port, 25... Filter-passing type infusion, blood transfusion boat, 2
6... Rapid infusion boat, 27... Air vent boat, z8... Filter-impermeable infusion boat, 29...
・Blood outflow port, 30... Filtering and defoaming member, 31... Deflector, 32... Mid-high support part, 33... Upper support body, 34... Inner cavity, 35... Filter, 36・・・
- Defoaming member, 37... Lower support, 38... Adhesive, 39... Rib, 40... Cylindrical body, 41... Annular void, 42... Hollow member, 43...・Top, 44...
・Lower, 45...Gap, 46...Tricot bag, 5
0...Deflector body, 51...Extension part, 52...
・Horizontal step part, 53... Rib, 54... Guide plate, 5
5... Rib FIG, 1 FIG, 3 FIG, 4 FJ (3,5

Claims (1)

[Claims] (1) A hollow body having a blood inlet at the top and a blood outlet at the bottom, a filtration and defoaming section provided above the hollow body, and further blood flowing out from the filtration and defoaming section into the hollow body. A guide portion for guiding to the body bottom is provided in a shape that converges from the filtration and defoaming portion toward the bottom of the hollow body, and the distance between the blood outflow portion of the filtration and defoaming portion and the blood receiving portion of the guide portion is A blood reservoir having a length equal to or smaller than the length of a blood droplet, and configured such that at the end of the guide part, the blood flow flowing on the convergent inner surface of the guide part is divided into rivulets.