JP3231077B2 - Blood reservoir - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood reservoir having a defoaming device for separating and removing air bubbles in blood.

[0002]

2. Description of the Related Art In cardiac surgery, for example, a blood pump is operated to remove blood from a patient's vein, gas is exchanged by an artificial lung, and this blood is returned to the patient's artery. Extracorporeal blood circulation is performed. A line is also provided for aspirating blood from the operative field, filtering out and removing foreign matter, and returning blood. Such an artificial lung extracorporeal blood circulation circuit includes a blood reservoir for temporarily storing the blood removed,
A blood reservoir (cardiotomy reservoir) for filtering and temporarily storing blood aspirated from the surgical field is installed.

[0003] Such a blood reservoir has a buffer function for adjusting the amount of blood in the circuit and keeping the amount of blood returned constant.
A defoaming device is installed in the blood reservoir and has a function of removing air bubbles in blood.

In this defoaming device, generally, a filtering member is disposed so as to surround a blood introducing portion to a blood reservoir, a silicone antifoaming agent is carried on the filtering member, and blood passes through the filtering member. In doing so, there is known a configuration in which bubbles mixed into blood are defoamed by contacting an antifoaming agent, but in such a defoaming device, when blood passes through a filtration member, The antifoaming agent may come off and enter the blood. Silicone used as an antifoaming agent is an inert substance and is hardly harmful per se, but because it is not metabolized by the human body, it easily accumulates in the human body and clogs ultra-fine capillaries and blood vessels. Since it is possible, contamination into the blood should be avoided as much as possible.

[0005] In order to prevent the defoaming agent from being mixed into the blood, an antifoaming agent is carried only on the upper end of the defoaming element (defoaming member). (Japanese Unexamined Patent Publication (Kokai) No. 63-21064) discloses a defoaming device which is set above the maximum liquid level to prevent blood from contacting the antifoaming agent.

However, this defoaming device has the following disadvantages. That is, since the defoaming agent carrying region is set above the maximum blood level, when the blood inflow is relatively small and the average or lower blood storage volume is maintained, the blood fluid There is a considerable distance between the surface and the lower end of the defoamer-carrying region, where air bubbles always remain and adhere to the inside of the defoaming element. For this reason, the ratio of the effective area to the entire area of the defoaming element decreases, and the pressure loss increases, which causes an increase in the priming amount.

In addition, when the blood inflow increases rapidly from the above state and the blood level rises, the residual bubbles near the blood level are pushed up to the defoaming agent-carrying region along with this. Since a large amount of air bubbles corresponding to the blood inflow amount newly flow into the defoaming device, it can no longer be defoamed,
In particular, air bubbles may flow out of the defoaming device without being defoamed due to the small area of the defoaming agent carrying region.

[0008] As described above, the defoaming apparatus described in Japanese Patent Application Laid-Open No. 63-21064 has a drawback that a stable defoaming effect cannot be obtained with respect to the increase and decrease of air bubbles due to the change in the amount of stored blood.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to minimize the incorporation of an antifoaming agent into blood and to stably obtain an excellent air bubble removing ability even with a change in the amount of stored blood. It is to provide a blood reservoir.

[0010]

This and other objects are attained by the present invention which is defined below as (1). In addition, the following (2)-
(6) is preferred.

(1) A blood reservoir having a housing having a blood inlet and a blood outlet, and a defoaming device installed in the housing so as to communicate with the blood inlet, wherein the defoaming device is provided. Includes a blood introduction tube connected to the blood inlet, a filter member, and a defoaming member that is installed above the filter member and carries an antifoaming agent, and the filter member has a lower side. A first filter portion substantially not carrying an antifoaming agent, and a second filter portion carrying an antifoaming agent on an upper side.

(2) The first filter section and the second filter section
The blood reservoir according to (1), wherein the boundary with the filter portion is formed within a range of a liquid level corresponding to a blood storage amount in a range of 5 to 75% of the maximum blood storage amount.

(3) The above (1) or (1), wherein the blood introduced from the blood inlet is introduced into the defoaming device by the blood introducing tube without contacting at least the defoaming member. The blood reservoir according to 2).

(4) The above (1) to (1), wherein the lower end of the defoaming member is joined to the upper end of the second filter portion.
The blood reservoir according to any one of (3).

(5) The blood reservoir according to any one of the above (1) to (4), wherein the defoaming member is made of a material having lower blood passage resistance than the filter member.

(6) The blood reservoir according to any one of (1) to (5), wherein the amount of the defoamer carried on the defoaming member is larger than the amount of the defoamer carried on the second filter portion. .

[0017]

The blood that has flowed into the defoaming device via the blood inlet formed in the upper part of the housing and the blood inlet tube connected to the blood inlet passes through the filter member and is mixed with the blood at this time. Air bubbles are separated and removed. That is, blood passes through the eyes (pores) of the filter member, flows out of the filter member, and is stored in the blood storage space in the housing. On the other hand, air bubbles cannot pass through the eyes of the filter member, and Float along the inner surface of the filter member due to the buoyancy of blood and the effect of washout due to blood flow,
It accumulates near the blood surface.

At the average blood storage volume, most of the blood passes through the first filter portion, which does not substantially carry an antifoaming agent, so that the antifoaming agent comes into contact with blood and enters the blood. There is no.

An antifoaming agent is carried in the second filter portion of the filter member above the first filter portion, and bubbles near the liquid surface of the blood accumulate to some extent and rise, and the amount of stored blood increases. When the blood level rises, the air bubbles near the blood level come into contact with the second filter portion and are broken by the action of the antifoaming agent. The broken bubbles are exhausted to the outside of the defoaming device as air.

The boundary between the first filter section and the second filter section is lower than the blood liquid level at the maximum blood storage volume, and in particular, the liquid level corresponding to the blood storage volume in the range of 10 to 75% of the maximum blood storage volume. Is set within the range, it is possible to quickly remove the bubbles in response to the accumulation of bubbles and the rise in the liquid level, and the frequency of contact of blood with the second filter portion is small. The amount of the antifoaming agent carried on the surface is detached and mixed into the blood.

If the blood flow level further rises due to an increase in the inflow of blood, bubbles near the blood liquid level also rise, and come into contact with the defoaming member to be broken by the action of the defoamer. Foam. This defoaming member has a higher defoaming ability than the second filter portion, and quickly defoams rising bubbles.

When the lower end of the defoaming member is set near or above the blood liquid level at the maximum blood storage volume, blood hardly contacts the defoaming member. Therefore, even if the defoaming agent is detached from the defoaming member, the amount is extremely small.

The blood thus defoamed by the defoaming device is stored in the blood storage space, and flows out of the housing from a blood outlet formed in a lower portion of the housing.
The amount of the air bubbles and the defoamer in the blood is extremely small.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a blood reservoir according to the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

FIG. 1 is a side view showing a configuration example of the blood reservoir of the present invention, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG.
It is sectional drawing in the BB line in FIG. As shown in FIG. 1, the blood reservoir 1 of the present invention has a housing 2 including a housing body 3 and a lid 4. This housing 2
Is formed a blood storage space 25 for storing blood.

The housing body 3 has a box shape having a protruding portion 31 protruding downward on the left side in FIG.
A tubular blood outlet 6 communicating with the blood storage space 25 is formed below the protrusion 31. This blood outlet 6
Is connected to, for example, a tube of a blood supply line of an extracorporeal blood circulation circuit.

The cover 4 is fitted to the upper end of the housing body 3 so as to cover the upper opening of the housing body 3.
Two tubular blood inlets 5 a and 5 b communicating with the blood storage space 25 are formed at predetermined positions of the lid 4. Among these, the blood inlet 5a is connected to, for example, a tube of a blood removal line of an extracorporeal blood circulation circuit,
The blood inlet 5b is connected to, for example, a tube of a blood suction line from an operation field.

A priming liquid inlet 5c used for injecting a priming liquid into a defoaming device 7a to be described later is formed on the side of the blood inlet 5a. A degassing port 5d is formed on the side of the blood inlet 5a opposite to the priming liquid inlet 5c. Defoaming device 7 described later
a part of the air bubbles broken by a
Is discharged to the outside as air. In addition, the inflow and outflow of air accompanying the increase and decrease of blood in the blood reservoir 1 are performed through the deaeration port 5d.

A plurality of blood inlets 5e for suctioning blood into the heart cavity are formed on both sides of the blood inlet 5b. In such a housing 2, the blood storage space 25
Is not particularly limited, for example, 30
About 00-5000ml, 1000-2500 for children
It is preferably about ml.

The constituent materials of the housing body 3 and the lid 4 are, for example, polycarbonate, acrylic resin,
Examples thereof include polyethylene terephthalate, polyethylene, polypropylene, polystyrene, polyvinyl chloride, acryl-styrene copolymer, acryl-butadiene-styrene copolymer, and among them, polycarbonate, acrylic resin, polystyrene, and polyvinyl chloride are particularly preferable. Is preferred.

The housing body 3 and the lid 4 are
It is preferably substantially transparent so that the amount of stored blood and the state of blood inside can be visually checked. The front (left end face in FIG. 1) and side faces of the housing body 3 are
Preferably, a scale (not shown) indicating the amount of stored blood is provided.

The blood reservoir 1 is provided with two defoamers 7a and 7b for removing bubbles contained in the blood flowing into the blood storage space 25. Hereinafter, the configurations of these defoaming devices will be sequentially described.

As shown in FIG. 2, the defoaming device 7a communicates with the blood inlet 5a, and includes a blood introduction tube 8 connected to the blood inlet 5a, a filter member 9, and a filter member 9. And an anti-foaming member 10 installed above.

The blood introduction tube 8 is a straight tubular member extending substantially vertically, and has an upper end connected to the blood inlet 5a. The lower end of the blood introduction tube 8 is extended to near the bottom in the defoamer 7a. This allows
The blood introduced into the blood introduction tube 8 from the blood inlet 5a is
The defoaming device 7a is supplied to the inside of the defoaming device 7a without contacting the defoaming member 10 and the second filter portion 92, which will be described later, thereby preventing the defoaming agent from being mixed into the blood when such blood is introduced.

In the defoaming device 7a, a blood introduction tube 8 is provided.
A priming liquid introduction pipe 11 having a smaller diameter is provided, and the upper end thereof is connected to the priming liquid inlet 5c.
Further, the lower end of the priming liquid introduction tube 11 is extended to near the bottom in the defoaming device 7a, similarly to the blood introduction tube 8.

The constituent materials of the blood introduction tube 8 and the priming liquid introduction tube 11 are, for example, polycarbonate,
Acrylic resin, polyethylene terephthalate (PE
T), polymer materials such as polybutylene terephthalate (PBT), polyethylene, polypropylene, polystyrene, polyvinyl chloride, acrylic-styrene copolymer, acrylic-butadiene-styrene copolymer, various types of glass, alumina, silica, etc. Examples thereof include ceramics, metals such as stainless steel, aluminum, copper, and titanium, various carbon materials, and the like, or a combination of two or more of them. Among them, polyvinyl chloride, polycarbonate, polystyrene, and PET are particularly preferable. , Stainless steel is preferred.

Around the blood introduction tube 8 and the priming liquid introduction tube 11, a filter member 9 and a defoaming member 10 are provided. The filter member 9 has a function of removing foreign matter and bubbles in blood,
It is composed of a first filter section 91 at the bottom in the figure and a second filter section 92 above the first filter section. The first filter portion 91 does not substantially carry an antifoaming agent, and the second filter portion 92 carries an antifoaming agent as described later.

The material of the filter member 9 is made of a porous material having sufficient blood permeability. Examples of such a porous material include a mesh (net) -like material, a woven fabric, a nonwoven fabric, and the like, and these can be used alone or in any combination (especially, by laminating). In the present invention, it is preferable that the filter member 9 includes a mesh member. This is because the mesh is excellent in blood permeability, has high opening accuracy, and can effectively remove bubbles and the like.

Here, the mesh is a sheet-like member having a regularly arranged mesh.
Examples include fiber woven or knitted articles, integrally molded articles, and processed articles.

The constituent material of the filter member 9, particularly, the constituent material of the mesh includes polyester such as PET and PBT, nylon (polyamide), polymer such as polyolefin such as tetron, rayon, polypropylene and polyethylene, and polyvinyl chloride. Material, aluminum,
Metal materials such as stainless steel, or a combination of two or more of these materials may be mentioned.
In particular, polyester, polypropylene, polyethylene,
Stainless steel is preferred.

The opening of the mesh of the mesh used for the filter member 9 is preferably about 15 to 300 μm, particularly preferably 20 to 200 μm. If it exceeds 300 μm, fine bubbles may pass through the mesh network together with blood, and if it is less than 15 μm, the resistance to blood passage increases and the level of blood in the defoaming device 7a rises. This is because there is a tendency to do so.

The filter member 9 may be subjected to a hydrophilic treatment such as a plasma treatment or a coating of a hydrophilic polymer material, if necessary, in order to further improve the blood permeability. In this case, the hydrophilic treatment such as the plasma treatment may be performed according to a conventional method.

With the filter member 9 as described above, for example, bubbles having a diameter of about 20 μm or more can be effectively removed. Since such a filter member 9 itself has low rigidity, in the configuration example shown in FIG. 2, the filter member 9 is supported and fixed by a lattice-shaped frame member 12. As the constituent material of the frame member 12, the same material as that of the blood introduction tube 8 can be used.

The second filter portion 92 of the filter member 9
The antifoaming agent carried on the substrate has a function of breaking bubbles when air bubbles come into contact with it, and typical examples thereof include silicone (compound type containing silica, oil type, etc.). Such a method of supporting the defoaming agent on the second filter portion 92 is, for example, by impregnating, applying or spraying a material containing a defoaming agent, followed by drying (for example, 30 ° C., 180 minutes). Performed by

The position of the boundary 94 between the first filter section 91 and the second filter section 92 will be described later in detail. Defoaming member 1 installed above filter member 9
0 carries the same defoaming agent as described above. The method of supporting the defoaming agent on the defoaming member 10 is the same as described above.

In the illustrated example, the outer surface of the defoaming member 10 is covered with the extension 93 of the filter member 9, but this extension 93 can be regarded as a part of the defoaming member 10. Further, such an extension 93 may not be present, or only a part of the outer surface of the defoaming member 10 may be covered.

Examples of the material of the defoaming member 10 include foams such as foamed polyurethane, foamed polyethylene, foamed polypropylene, and foamed polystyrene, meshes, woven fabrics, nonwoven fabrics, and sintered bodies such as porous ceramics and resins. Although various porous materials can be mentioned, it is preferable to use a material having relatively low blood passage resistance (pressure loss).

When a foam having a low resistance to the passage of blood, such as a foamed polyurethane or other porous material, has a pore size of about 20 μm to 5 mm, particularly 30 μm.
It is preferable to set it to about μm to 2 mm. The lower end surface of the defoaming member 10, that is, the position of the boundary 101 between the defoaming member 10 and the second filter portion 92 is near or above the liquid level (maximum liquid level L _max ) at the maximum blood storage volume of the blood reservoir 1. It is preferred to be above.

Here, the maximum blood storage volume means a limit blood volume beyond which the blood may overflow from the blood storage tank 1, and varies depending on the function and structure of the blood storage tank 1. 70-100 of the real volume of the blood storage space 25
%.

In the filter member 9, the position of the boundary 94 between the first filter portion 91 and the second filter portion 92 is preferably 5 to 75% of the maximum blood storage amount of the blood reservoir 1.
, More preferably within the range of the liquid level corresponding to the blood storage amount in the range of 20 to 70%. If it is less than 5%, the frequency of contact of the blood with the second filter portion 92 increases, and the amount of the antifoaming agent mixed into the blood tends to be relatively large. No antifoaming agent is mixed into the blood, but the blood
Is increased, the amount of air bubbles accumulated in this portion increases, and the defoaming ability decreases.

Further, the position of the boundary 94 is determined by the defoaming device 7a.
It is preferably set to around the normal liquid level L ₀ of the blood inside.

Here, the normal liquid level L ₀ is clinically defined as the amount of blood obtained by subtracting the priming volume of the circulation circuit other than the blood reservoir 1 and the optimal circulating blood volume of the patient from the total circulating blood volume. It refers to the liquid level when present in the blood storage space 25 of the blood reservoir 1, and the blood volume increases mainly by infusion or injection of a cardioplegic agent, and decreases by urination. Actually, it is determined by the balance between the total blood inflow from the blood inlets 5 a and 5 b and the blood inlet 5 e in the heart chamber and the outflow from the blood outlet 6. The amount of blood stored in the blood reservoir 1
Usually, at the start of blood circulation, it starts with the minimum amount that can be safely circulated (about 10 to 30% of the maximum blood volume), and then circulates at about 20 to 50% of the maximum blood volume. In addition, when the cardioplegic agent is injected, the maximum amount (40 to 7 of the maximum blood storage amount) is obtained.
(0%). Therefore, the defoaming device 7a
Actual blood liquid level in the inner varies vertically from the common fluid level L _0.

Defoaming member 10 and second filter section 92
The carrying amount (total weight per unit volume) of the defoaming agent in each of the above is not particularly limited, but the carrying amount of the defoaming agent in the defoaming member 10 is equivalent to the carrying amount of the defoaming agent in the second filter portion 92. Or more is preferred. In the defoaming member 10 and the second filter portion 92, since the latter is located below, the frequency of contact with blood is high due to the fluctuation of the blood liquid level. If it is provided, the amount of antifoam mixed into the blood is further reduced,
In addition, an excellent defoaming effect can be stably obtained.

In the present invention, it goes without saying that the defoaming members 10 and the second filter portion 92 may carry the same amount of defoaming agent. The defoamer in the defoaming member 10 and the second filter unit 92 is
They may have the same composition or different compositions (for example, different types and amounts of additives).

In the configuration shown, the second filter unit 9
The second filter section 91 and the first filter section 91 are different in whether or not an antifoaming agent is carried, and have substantially the same configuration in other respects. However, these boundaries do not have to be strict. For example, near these boundaries, the first filter unit 9
A configuration in which the carried amount of the antifoaming agent increases continuously or stepwise from 1 to the second filter section 92 may be adopted.

In the illustrated configuration, the boundary 94 and the boundary 1
01 is a plane that is substantially parallel to the blood surface, but is not limited thereto, and may be a plane that is not parallel to the blood surface or a plane shape (for example, a curved surface).

Next, the defoaming device 7b will be described. Regarding the defoaming device 7b, description of the same matters as those of the defoaming device 7a is omitted. As shown in FIG. 3, the defoaming device 7b communicates with the blood inlet 5b,
It constitutes a cardiotomy reservoir. The defoaming device 7b includes a blood introduction tube 14 connected to the blood inlet 5b, a filter member 15, an antifoaming member 16 installed at an upper portion inside the filter member 15, and a blood distribution member 17. Have.

The blood introduction tube 14 is a tubular member that extends substantially vertically and has an inner diameter that gradually decreases downward.
The upper end is provided with a blood inlet 5b and an intracardiac blood inlet 5
e. Further, the lower end of the blood introduction tube 14 is located slightly above the lower end surface 161 of the defoaming member 16 to be described later, whereby the blood introduced into the blood introduction tube 14 from the blood inlet 5b is It falls from the lower end of the pipe 14 and is supplied into the defoaming device 7a without contacting the defoaming member 16.

A preferably cylindrical defoaming member 16 is provided around the blood introduction tube 14, and a preferably cylindrical filter member 15 is provided around the outer periphery thereof. At the lower end opening of the filter member 15, a blood distribution member 17 protruding toward the inside of the defoaming device 7b is mounted. This blood distribution member 17 is
4 has a function of uniformly distributing the blood falling from the lower end of the filter member 4 radially toward the inner surface of the filter member 15.

The lower end of the filter member 15 is fixed to the outer periphery of the blood distribution member 17 with a filler 18, and the upper ends of the filter member 15 and the defoaming member 16 are filled with a blood introduction tube by the filler 18. 14 is fixed to the base. The filter member 15 includes a first filter section 151 and a second filter section 152 similar to those described above. The first filter 151 does not substantially carry an antifoaming agent, and the second filter 152 has
An antifoaming agent as described above is carried.

In this case, as shown in FIG. 4, the filter member 15 is composed of an inner layer 155 formed by pleating the above-mentioned material and an outer layer 156 adhered to the outer periphery of the inner layer 155. Have been.

Since the inner layer 155 is formed in a pleated shape, the effective area of the filter member 15 can be sufficiently secured. Further, the outer layer 156 has a function of regulating the deformation of the inner layer 155 with the defoaming member 16 and holding the filter member 15 in a fixed shape, and a relatively hard mesh, net or frame member is used. It is preferably used.

A defoaming member 16 similar to that described above is provided on the upper inner peripheral surface of the filter member 15 so as to overlap the second filter portion 152. In this defoaming member 16,
The same defoaming agent as described above is carried. It is preferable that the position of the lower end surface 161 of the defoaming member 16 be near or above the maximum liquid level _Lmax .

In the filter member 15, the first
The position of the boundary 153 between the filter unit 151 and the second filter unit 152 is preferably in the range of 5 to 75%, more preferably in the range of 20 to 70% of the maximum blood storage volume of the blood reservoir 1 for the same reason as described above. It is preferably set within the range of the liquid level corresponding to the stored blood volume of the blood, and more preferably, around the normal liquid level L ₀ of the blood in the defoaming device 7b.

The difference in the composition and amount of each defoaming agent in the defoaming member 16 and the second filter portion 152, and the shape and clarity of the boundary 153 are the same as described above. In the illustrated configuration example, one housing 2
Although a device in which two defoaming devices 7a and 7b are installed is mentioned, the present invention is not limited to this, and a device in which one defoaming device is installed in one housing may be used.

As described above, the blood reservoir of the present invention has been described with reference to the illustrated configuration example, but the present invention is not limited to this. The use of the blood reservoir of the present invention is not particularly limited, but in an extracorporeal blood circulation circuit, a blood reservoir for temporarily storing the removed blood, or a device for filtering foreign substances from blood sucked from an operation field. It is preferably applied to a blood reservoir (cardiotomy reservoir) for temporarily storing blood.

Next, the blood reservoir of the present invention will be described in more detail based on specific examples. (Example 1) A blood reservoir having a structure in which the housing having the structure shown in FIG. 1 was equipped with the defoaming device shown in FIG. 2 was produced. Various conditions in this blood reservoir are as shown in Table 1 below.

[0068]

[Table 1]

(Example 2) A blood reservoir similar to that of Example 1 was used except that the boundary position between the first and second filter portions was set at a liquid level at a blood storage amount of 10% of the maximum blood storage amount. Produced.

(Example 3) A blood reservoir similar to that of Example 1 was used except that the boundary position between the first and second filter portions was set at a liquid level at a blood storage amount of 70% of the maximum blood storage amount. Produced.

(Example 4) In order to reduce the amount of the defoaming agent carried in the second filter portion to the amount of the defoaming agent carried by the defoaming member,
The same blood reservoir as in Example 1 was prepared except that the second filter portion was loaded with a defoaming agent in 0.5% silicone / 1000 ml Freon and air-dried.

(Comparative Example) A blood reservoir similar to that of Example 1 was prepared except that the defoaming agent was not carried on the second filter portion.

The following experiments were performed on the blood reservoirs of Examples 1 to 4 and Comparative Example. Blood is supplied from the blood inlet at an average flow rate of 4000 ml / min, and air is bubbled into this blood at a rate of 100 ml / min (about 1 to 5 mm in diameter).
Was mixed, and after a predetermined time had elapsed, the state of bubbles in the blood reservoir was observed. The supply amount of blood fluctuated within a range of ± 500 ml / min.

As a result, in the blood storage tanks of Examples 1 to 4, air bubbles continued to be normally removed even after 10 minutes or more, whereas in the blood storage tank of the comparative example, the accumulated amount of air bubbles Gradually increased, and after 10 minutes, air bubbles erupted from the upper part of the defoaming unit. In the blood reservoirs of Examples 1 to 4, when the concentration of the antifoaming agent in the blood flowing out from the blood outlet was measured, it was below the measurement limit.

[0075]

As described above, according to the blood reservoir of the present invention, the first filter portion which does not substantially carry the defoamer, the second filter portion which carries the defoamer, and the defoamer With a three-layer structure with an antifoaming member that carries blood, even if the blood level in the blood reservoir and the amount of air bubbles in the blood reservoir change due to the change in blood inflow, it can be effectively removed. It can foam, and the frequency of contact of blood with the antifoaming agent is low, and the amount of the antifoaming agent mixed into the blood can be suppressed to the maximum, so that there is no adverse effect on the living body. That is, it is possible to stably obtain an excellent defoaming effect and to suppress the defoaming agent from being mixed into blood.

[Brief description of the drawings]

FIG. 1 is a side view showing a configuration example of a blood storage tank of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a sectional view taken along line BB in FIG. 1;

FIG. 4 is a sectional view taken along line CC in FIG. 3;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Blood storage tank 2 Housing 25 Blood storage space 3 Housing main body 31 Projection part 4 Lid 5a, 5b Blood inlet 5c Priming liquid inlet 5d Deaeration port 5e Intracardiac blood inlet 6 Blood outlet 7a, 7b Defoaming device 8 Blood introduction tube 9 filter member 91 first filter portion 92 second filter portion 93 extension portion 94 boundary 10 defoaming member 101 boundary 11 priming liquid introduction tube 12 frame member 14 blood introduction tube 15 filter member 151 first filter portion 152 second Filter part 153 Boundary 155 Inner layer 156 Outer layer 16 Antifoaming member 161 Lower end face 17 Blood distribution member 18 Filler L ₀ Regular liquid level L _max maximum liquid level

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) A61M 1/14-1/36

Claims (6)

(57) [Claims] 1. A blood reservoir having a housing having a blood inlet and a blood outlet, and a defoaming device installed in the housing so as to communicate with the blood inlet, wherein the defoaming device is A blood introduction pipe connected to the blood inlet, a filter member, and a defoaming member installed above the filter member and carrying an antifoaming agent, wherein the filter member is provided on a lower side. A blood reservoir comprising: a first filter portion that does not substantially carry a certain antifoaming agent; and a second filter portion that carries an antifoaming agent on the upper side. 2. A boundary between the first filter section and the second filter section is formed within a range of a liquid level corresponding to a blood storage amount in a range of 5 to 75% of a maximum blood storage amount. 2. The blood reservoir according to 1. 3. The apparatus according to claim 1, wherein the blood introduced from the blood inlet is introduced into the defoaming device by the blood introduction tube without contacting at least the defoaming member. Blood reservoir. 4. The blood reservoir according to claim 1, wherein a lower end of the defoaming member is joined to an upper end of the second filter. 5. The defoaming member is made of a material having lower blood passage resistance than the filter member.
5. The blood reservoir according to any one of items 4 to 4. 6. The blood reservoir according to claim 1, wherein the amount of the defoamer carried on the defoaming member is larger than the amount of the defoamer carried on the second filter portion.