JP7342583B2 - blood reservoir - Google Patents

Description

The present invention relates to a blood reservoir.

In heart surgery, a heart-lung machine is used. A heart-lung machine mainly includes a blood storage tank, a blood pump, a heat exchanger, a blood circuit, an artificial lung, and the like. In such a heart-lung machine, blood removed from the patient's veins (venous blood) and blood aspirated from the surgical field (aspirated blood) are first pumped into a blood reservoir, where they are temporarily stored. Ru. This blood is sent to a heat exchanger by a blood pump, and the temperature of the blood is adjusted in the heat exchanger. In the oxygenator, temperature-controlled gas exchange (carbon dioxide removal, oxygenation) of the blood takes place. Finally, this blood is returned to the patient's body as arterial blood.

Such a heart-lung machine temporarily takes over the functions of the heart and lungs during heart surgery. For this reason, in the heart-lung machine, it is necessary to remove foreign substances, air bubbles, etc. mixed into the blood during surgery before sending the blood back to the patient. For example, Patent Document 1 discloses a blood reservoir (a blood reservoir with a built-in cardiotomy reservoir) that can simultaneously remove foreign substances such as bone fragments and meat fragments and air bubbles from blood.

Japanese Patent Application Publication No. 2010-88737

The amount of blood stored in the blood reservoir disclosed in Patent Document 1 is managed using a level sensor provided outside the blood reservoir. Specifically, a band-shaped blood storage amount measurement area extending from the bottom to the top is provided on the side surface of the blood storage tank. A scale indicating the amount of blood stored is attached in advance to this blood storage amount measurement area. Based on this scale, a level sensor is attached to the scale position of the amount of stored blood to be detected, and the liquid level of the amount of stored blood is detected.

In the blood storage tank disclosed in Patent Document 1, the blood storage amount measurement area provided on the side surface of the housing is provided with a curved surface that bulges laterally so as to extend in the vertical direction. More specifically, it is formed so that a part of the cylindrical surface extends in the vertical direction. When aspirated blood is collected into the blood reservoir, the inside of the blood reservoir becomes under negative pressure. In this case, if the housing is deformed by this negative pressure, the position of the liquid level changes, making it impossible to accurately manage the amount of blood stored. Therefore, from the viewpoint of preventing deformation of the housing, curved surfaces extending in the vertical direction are provided on the side surfaces of the housing in order to increase the rigidity of the housing.

Here, in a normal use state of the blood reservoir, a certain amount of aspirated blood is stored inside the blood reservoir. As a result, the lower end of the filtering means disposed inside the blood reservoir is immersed in the stored blood, and the aspirated blood stored in the blood reservoir is introduced into the stored blood through the filtering means.

However, due to the occurrence of unavoidable events during surgery, the amount of blood stored inside the blood reservoir may be significantly reduced, and furthermore, a large amount of aspirated blood may be stored in the blood reservoir through the filtering means. In this case, as a result of the lower end of the filtering means being located above the liquid level of the stored blood, the aspirated blood stored in the blood storage tank through the filtering means falls onto the liquid level of the stored blood. As a result, bubbles may be created on the surface of the stored blood.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a blood storage tank having a configuration capable of suppressing the creation of bubbles on the liquid surface of stored blood.

The blood storage tank according to this disclosure is a blood storage tank for storing venous blood and/or aspirated blood, and includes a housing having a blood inflow part and a blood outflow part; A filtration means for filtering blood flowing in from the inflow part, and a guide member disposed between the filtration means and the outflow part to guide the blood filtered by the filtration means in the direction of the outflow part. A blood storage amount measurement area for measuring the amount of blood stored inside the housing is provided on a side surface of the housing, the blood storage amount measurement area includes a flat surface in a lower area, and the filtration means is configured to The suction blood filtration means includes a venous blood filtration means for filtering venous blood and a suction blood filtration means for filtering the suction blood, and the suction blood filtration means is located between the blood storage amount measurement area of the housing and the venous blood filtration means. , is arranged to face the blood storage amount measurement region, and a lower region of the suction blood filtration means is arranged substantially parallel to the inner surface of the flat surface of the blood storage amount measurement region.

In another aspect of the blood storage tank, the lower region of the suction blood filtration means has a bottom member having a plate-like appearance as a whole, and the bottom member are arranged in parallel.

In another embodiment of the blood reservoir, the shortest distance between the inner surface of the flat surface and the bottom member is 0.50 mm to 2.0 mm.

According to the blood storage tank in this disclosure, it is an object of the present invention to provide a blood storage tank that has a configuration that can suppress the creation of bubbles on the liquid surface of stored blood.

FIG. 2 is an external view of a blood reservoir according to an embodiment. It is an exploded perspective view of the 2nd support member of the filter support unit of an embodiment. It is a perspective view of the filter holding member which constitutes the 2nd support member of an embodiment. It is a perspective view of the bottom member which constitutes the 2nd support member of an embodiment. FIG. 2 is a longitudinal cross-sectional view of a blood reservoir according to an embodiment. 2 is a sectional view taken along the line VI-VI in FIG. 1. FIG. 2 is a sectional view taken along the line VII-VII in FIG. 1. FIG. 6 is a partially enlarged view of the area surrounded by VIII in FIG. 5. FIG. 9 is a sectional view taken along the line IX-IX in FIG. 8. FIG.

Hereinafter, embodiments of a blood reservoir based on the present invention will be described with reference to the drawings. In the embodiments described below, when references are made to the number, amount, etc., the scope of the present invention is not necessarily limited to the number, amount, etc., unless otherwise specified. It has been planned from the beginning to use the configurations shown in each of the above embodiments in appropriate combinations.

In the present invention, venous blood refers to blood removed from a patient's blood vessel via a cannula, and aspirated blood refers to blood (vented blood and suctioned blood) aspirated from inside and outside the heart, which is the surgical field. In the present invention, foreign matter refers to substances other than blood that may be contained in aspirated blood, such as fat globules, pieces of meat, bone pieces, denatured proteins, and aggregates.

(Configuration of blood storage tank 1)
The configuration of the blood reservoir 1 of this embodiment will be described below with reference to FIGS. 1 to 7. 1 is an external view of the blood storage tank 1 of this embodiment, FIG. 2 is an exploded perspective view of the second support member 22 of the filter support unit 20, and FIG. 3 is a filter holding member constituting the second support member 22. 222, FIG. 4 is a perspective view of the bottom member 322 constituting the second support member 22, FIG. 5 is a sectional view of the blood reservoir, and FIG. 6 is a sectional view taken along the line VI-VI in FIG. , FIG. 7 is a sectional view taken along the line VII-VII in FIG. Note that in FIGS. 6 and 7, the internal configuration is omitted.

The blood storage tank 1 includes a housing 10, a filter support unit 20, a blood introduction tube 30, a venous blood filtration means 40, a suction blood filtration means 50, and a guide member 60.

The housing 10 has a housing body 11 and a lid 12, as shown in FIG. As shown in FIG. 5, a storage space S for storing blood is formed inside the housing 10. The storage space S is an internal space of the housing 10 that is formed by attaching the lid 12 to the housing body 11.

The housing main body 11 is formed into a box shape with a partially open opening. The opening of the housing body 11 is formed in a generally elliptical or square shape. As shown in FIGS. 1 and 5, the housing body 11 has a box-shaped portion 11a and a protruding portion 11b. The box-shaped portion 11a forms a storage space S on the side into which blood flows, that is, an upper storage space Sa. The protrusion 11b forms a storage space S on the side from which blood flows out, that is, a lower storage space Sb. The protruding portion 11b is a part of the bottom of the box-shaped portion 11a that protrudes forward, and is formed integrally with the box-shaped portion 11a. A tubular blood outflow port 11c communicating from the storage space S to the outside is provided at the bottom of the protrusion 11b. The blood outlet 11c is connected, for example, to a tube of a blood supply line of an extracorporeal blood circulation circuit.

The front side surface of the box-shaped part 11a and the front side surface of the protrusion part 11b are formed on the same plane. A scale (not shown) for checking the amount of blood stored is provided on the same side. The bottom of the box-shaped portion 11a and the bottom of the protrusion 11b face the opening of the housing body 11.

In FIG. 1, the front direction is the direction indicated by arrow X1, and the rear direction is the direction indicated by arrow X2, which is opposite to arrow X1. The direction of arrow Z1 and arrow Z2 extending perpendicularly to arrow X1 and arrow X2 in the same virtual plane as the virtual plane including arrow X1 and arrow X2 is called a lateral direction. Furthermore, the directions of arrow X1, arrow X2, arrow Z1, and arrow Y1 and arrow Y2 extending in a direction orthogonal to the direction of arrow Z2 are referred to as a vertical direction. When the blood reservoir 1 is in use, the arrow Y1 points upward and the arrow Y2 points downward.

The lid body 12 is fitted and attached to the housing body 11 so as to cover the opening of the housing body 11, as shown in FIGS. 1 and 5. The lid 12 is provided with a first blood inlet 12a and a second blood inlet 12b. The first blood inlet 12a is connected, for example, to a tube of a blood removal line for venous blood in an extracorporeal blood circulation circuit. The second blood inlet 12b is connected, for example, to a tube of a blood removal line for sucking blood in the extracorporeal blood circulation circuit. These first blood inlet 12a and second blood inlet 12b communicate with the storage space S, for example, the upper storage space Sa from the outside in a state where the lid body 12 is attached to the housing body 11.

The lid 12 is provided with a vent (not shown) that allows air to enter and exit as the blood in the blood reservoir 1 increases or decreases. The air after defoaming and the air after bubble breakage is discharged to the outside from the degassing port.

Referring to FIGS. 1, 6, and 7, a band-shaped blood storage amount measurement area 11m extending in the vertical direction (vertical direction) is provided on the side surface of the housing body 11 located in the horizontal direction. This blood storage amount measurement area 11m includes a flat surface 11h located on the lower side (see FIG. 6) and a curved surface 11p located on the upper side (see FIG. 7).

The flat surface 11h has a flat cross section. The curved surface 11p has such a curved surface shape that its cross section forms part of a cylinder that bulges out toward the front. In this way, by providing the flat surface 11h on the front side surface of the housing body 11, when a level sensor (not shown) is attached to this area, the level sensor (not shown) can be attached to the flat surface. Since the level sensor is attached, it is possible to suppress the level sensor from peeling off. As a result, it is possible to suppress the occurrence of poor detection of the amount of stored blood.

In the upper region where the level sensor is not expected to be attached, a curved surface 11p is provided to suppress deformation due to negative pressure inside the blood reservoir 1 when aspirated blood is collected into the blood reservoir 1. It becomes possible to do so. This suppresses the occurrence of detection failures of the level sensor.

Examples of materials for forming the housing body 11 and the lid 12 include polycarbonate, acrylic resin, polystyrene, polyvinyl chloride, and the like. The housing main body 11 made of the material shown on the left is substantially transparent so that the amount of blood stored inside the blood storage tank 1 and the condition of the blood inside can be visually confirmed. is preferred.

The filter support unit 20 is for supporting the venous blood filtration means 40 and the suction blood filtration means 50, and is attached to the housing 10, for example, the lid 12. The filter support unit 20 includes a first support member 21 and a second support member 22, as shown in FIGS. 2 to 5. The first support member 21 is a portion that supports a venous blood filtering means 40, for example, a venous blood filter member 41, which will be described later. The first support member 21 has a frame structure and is attached to the back surface of the lid 12. When the blood reservoir 1 is in use, the first support member 21 is housed inside the housing body 11 so as to be inclined from the rear toward the front.

As shown in FIGS. 2 to 5, the second support member 22 is a member that supports a suction blood filtering means 50, for example, a first filter member 51 for suction blood and a second filter member 52 for suction blood, which will be described later. It is. The second support member 22 is attached to the back surface of the lid 12. Specifically, the second support member 22 includes a frame body 122, a filter holding member 222 that sandwiches the second filter member 52 for aspirated blood between the frame body 122, and a second filter member for aspirated blood. 52.

The frame body 122 is attached to the back surface of the lid body 12. The frame body 122 has two plate portions 122a facing each other, a connecting member 122b connecting the two plate portions 122a, and a claw portion 122c formed on the inner surface of each plate portion 122a. The second support member 22 is attached to the back surface of the lid 12 at the two plate portions 122a. The second filter member 52 for sucked blood is latched and attached to the plate part 122a in a state where it is placed over the plate part 122a and the connecting member 122b.

The filter holding member 222 is attached to the back surface of the lid 12. The filter holding member 222 is formed into a box shape that follows the outer shape of the frame body 122. The filter holding member 222 has openings formed at the top, center, and bottom. The upper opening 222a is for inserting the frame 122. The central opening 222b serves as a passage port through which blood that has passed through the first filter portion 52a of the second filter member 52 for sucked blood, such as a nonwoven fabric, mainly passes through. The lower opening 222c serves as a passage port through which blood that has passed through the second filter portion 52b of the second filter member 52 for aspirated blood, such as a mesh cloth (screen mesh), mainly passes through. The filter holding member 222 is attached to the lid 12 in a state where the second filter member 52 for sucked blood is placed on the frame 122.

The bottom member 322 is attached to the filter holding member 222. Specifically, the bottom member 322 is attached to the opening 222c formed in the filter holding member 222. The bottom member 322 is formed so that aspirated blood can pass through the bottom member 322 while supporting the bottom of the second filter member 52 for aspirated blood (second filter section 52b to be described later). The bottom member 322 is formed with a support portion 322a that supports the bottom of the second filter member 52 for sucked blood, and a passage portion 322b through which the sucked blood from the sucked blood filtering means 50 can pass. The support portion 322a is formed into a plate shape, contacts the bottom of the second filter member 52 for aspirated blood, and supports the bottom of the second filter member 52 for aspirated blood.

The passage portion 322b is formed into a rectangular cylindrical shape. In other words, the passage portion 322b is formed into a hollow beak shape. The passage portion 322b is provided with an opening portion 322c on opposing side surfaces. As a result, the aspirated blood passing through the passage 322b flows out not only from the tip of the passage 322b but also from the opening 322c.

When the bottom member 322 is attached to the filter holding member 222, the passage portion 322b is set at a predetermined inclination angle α with respect to the horizontal direction (see FIG. 5). Specifically, the bottom member 322 is attached to the filter holding member 222 so that the inclination angle α of the passage portion 322b with respect to the horizontal direction is about 65 degrees.

Further, when the bottom member 322 is attached to the filter holding member 222, the tip of the passage portion 322b of the bottom member 322 is arranged inside the protrusion 11b. Thereby, the filtered suction blood can be guided from the upper part of the protrusion 11b into the inside of the protrusion 11b.

The phrase "back surface of the lid 12" refers to the surface of the lid 12 opposite to the side where the first blood inlet 12a and the second blood inlet 12b are provided. The term "surface of the lid 12" refers to the surface of the lid 12 opposite to the back surface. That is, the term "surface of the lid 12" indicates the surface of the lid 12 on the side where the first blood inlet 12a and the second blood inlet 12b are provided.

The blood introduction tube 30 includes a blood introduction tube 31 for venous blood for guiding venous blood into the housing 10 from the first blood inflow port 12a, and a blood introduction tube 31 for guiding venous blood into the housing 10 from the second blood inflow port 12b. It has a blood introduction tube 32 for sucking blood.

The blood introduction tube 31 for venous blood is attached to the back surface of the lid body 12 at the position of the first blood inflow port 12a. The blood introduction tube 31 for venous blood is formed into a tubular shape, and is inserted and disposed inside the frame structure of the first support member 21 . When the lid 12 is attached to the housing body 11, the blood introduction tube 31 for venous blood has one end attached to the back surface of the lid 12, and the other end located inside the protrusion 11b. In other words, when the lid 12 is attached to the housing body 11, the blood introduction tube 31 for venous blood is diagonally directed from the first blood inlet 12a of the lid 12 toward the protrusion 11b of the housing body 11. It is arranged inside the housing 10 in an extended state. When the blood reservoir 1 is in use, the blood introduction tube 31 is housed inside the housing body 11 so as to be inclined downward from the rear side toward the front side.

The blood introduction tube 32 for sucking blood is attached to the back surface of the lid 12 at the position of the second blood inlet 12b. Specifically, the blood introduction tube 32 for suction blood is formed in a tubular shape, and is located between the second support member 22 and the lid 12 at the position of the second blood inlet 12b. Attached to the back. When the lid 12 is attached to the housing body 11, one end of the blood introduction tube 32 for aspirating blood is attached to the back surface of the lid 12, and the other end is located above the protrusion 11b. In other words, when the lid 12 is attached to the housing body 11, the blood introduction tube 32 for suction blood is directed downward from the second blood inlet 12b of the lid 12 toward the protrusion 11b of the housing body 11. The second support member 22 is disposed inside the frame body 122 in an extended state.

Note that although an example is shown in which the blood introduction tube 32 for aspirated blood is attached to the back surface of the lid body 12 at the position of the second blood inflow port 12b, the blood introduction tube 32 for aspirated blood is 2 may be integrally formed on the back surface of the lid body 12 at the position of the blood inlet 12b.

Venous hemofiltration means 40 is mounted inside housing 10 . The venous blood filtering means 40 has a filter member 41 for venous blood. The venous blood filter member 41 is for removing air bubbles from the venous blood introduced into the housing 10 from the first blood inlet 12a through the venous blood inlet pipe 31. For this reason, the pore diameter of the filter member 41 for venous blood is preferably about 20 μm to 40 μm.

The filter member 41 for venous blood is formed in the shape of a partially open bag, and the venous blood filtering means 40 is inclined from the rear direction to the front direction when the blood storage tank 1 is in use. , are arranged inside the housing 10. Specifically, the filter member 41 for venous blood is formed in the shape of a bag with an open top, and is attached to the outer surface of the first support member 21 of the filter support unit 20 . More specifically, the venous blood filter member 41 is attached to the first support member 21 of the filter support unit 20 so as to wrap around the frame structure of the first support member 21 of the filter support unit 20 . As a result, when the lid 12 is attached to the housing body 11, the venous blood filter member 41 extends diagonally from the first blood inlet 12a of the lid 12 toward the protrusion 11b of the housing body 11. It is placed inside the housing 10 in a state where the

The suction blood filtering means 50 is mounted inside the housing 10 . The suction blood filtering means 50 includes a first filter member 51 for suction blood and a second filter member 52 for suction blood. The suction blood filtration means 50 is provided on the side of the blood storage amount measurement region 11m located in the lateral direction of the housing body 11 with respect to the venous blood filtration means 40. Therefore, the suction blood filtration means 50 is located between the blood storage amount measurement area 11m of the housing 10 and the venous blood filtration means 40. Further, the suction blood filtering means 50 is located inside the housing body 11 so as to face the blood storage amount measurement region 11m.

The first filter member 51 for aspirated blood removes relatively large foreign substances and air bubbles from the aspirated blood introduced into the housing 10 from the second blood inlet 12b through the blood introduction tube 32 for aspirated blood. belongs to.

The first filter member 51 for sucking blood is formed in a hat shape with a partially open opening, and is disposed inside the housing 10 . The first filter member 51 for sucking blood is attached to the back surface of the lid body 12. Specifically, the first filter member 51 for aspirated blood has a flange 51a and a recess 51b. More specifically, in the first filter member 51 for aspirated blood, the recess 51b is fitted into the blood introduction tube 32 for aspirated blood, and the collar 51a is attached to the back surface of the lid 12. The flange portion 51a of the first filter member 51 for suction blood is supported by the second support member 22 attached to the lid body 12. Specifically, the collar portion 51a of the first filter member 51 for suction blood is supported by the claw portion 122c provided on the frame 122 of the second support member 22.

Foamed urethane is used for the first filter member 51 for sucking blood. The inner surface of the first filter member 51 for sucking blood, for example, the inner surface of the recess 51b, is coated with an antifoaming agent, such as silicone, which defoams when bubbles come into contact with it. Therefore, when the aspirated blood comes into contact with the inner surface of the first filter member 51 before it passes through the first filter member 51 for aspirated blood, the air bubbles contained in the aspirated blood are ruptured by the antifoaming agent. . After the aspirated blood passes through the first filter member 51 for aspirated blood, air bubbles larger than a predetermined size corresponding to the eye size of the first filter member 51 for aspirated blood are removed from the aspirated blood. When the aspirated blood passes through the first filter member 51 for aspirated blood, foreign matter is also removed from the aspirated blood. Here, for example, foreign matter larger than the eye size of the first filter member 51 for aspirated blood is removed from the aspirated blood.

The second filter member 52 for aspirated blood removes foreign objects and air bubbles from the aspirated blood that has passed through the first filter member, that is, relatively large foreign objects and air bubbles have been removed in the second filter member 52 for aspirated blood. It is intended to remove. The pore diameter of the second filter member 52 for aspirated blood is preferably about 20 μm to 200 μm.

The second filter member 52 for sucking blood is formed in the shape of a partially open bag, and is arranged inside the housing 10 . Specifically, the second filter member 52 for aspirating blood is formed in the shape of a bag with an open top. The second filter member 52 for aspirated blood is attached to the second support member 22 of the filter support unit 20 disposed outside the first filter member 51 for aspirated blood. For example, the second filter member 52 for sucking blood is placed over the plate portion 122a and the connecting member 122b, and is locked and attached to the plate portion 122a. In this state, the filter holding member 222 is attached to the frame 122. The bottom member 322 is attached to the opening 222c formed in the filter holding member 222. Thereby, the second filter member 52 for sucking blood is supported by the filter support unit 20 with the bottom portion folded back inward. In this state, the first filter member 51 for aspirated blood is arranged inside the second filter member 52 for aspirated blood.

When the aspirated blood passes through the second filter member 52 for aspirated blood, foreign matter that could not be removed by the first filter member 51 for aspirated blood is removed. At this time, air bubbles that could not be removed by the first filter member 51 for aspirated blood are removed from the aspirated blood. That is, foreign matter and air bubbles larger than a predetermined size corresponding to the size of the eyes (micropores) of the second filter member 52 for aspirated blood are removed from the aspirated blood. Here, as the aspirated blood passes through the second filter member 52 for aspirated blood, foreign matter and air bubbles having a size of 40 microns or more, for example, are removed from the aspirated blood.

Referring to FIG. 5, the guide member 60 located in the lower region of the suction blood filtration means 50 is disposed between the suction blood filtration means 50 and the blood outflow port 11c, and the guide member 60 is arranged between the suction blood filtration means 50 and the blood outflow port 11c. This is a member that guides the blood in the direction of the blood outflow port 11c.

Specifically, as shown in FIG. 4, the guide member 60 is attached to the second support member 22, that is, the bottom member 322. More specifically, the guide member 60 is formed into a plate shape, and is inserted and mounted inside the passage portion 322b of the bottom member 322. The bottom member 322 into which the guide member 60 is inserted has a plate-like appearance as a whole.

The guide member 60 is made of a foam material compressed in the thickness direction. For the guide member 60, a material having a density D corresponding to the inclination angle α of the bottom member 322, for example, the inclination angle α of the passage portion 322b of the bottom member 322 is used. For example, the guide member 60 is constructed of a material having a density D within a range of 0.12 g/cm ³ to 0.16 g/cm ³ . More specifically, the guide member 60 is made of a material having a density D of 0.13 g/cm ³ .

For example, when commercially available urethane foam with a density of 26 kg/m ³ to 30 kg/m ³ is compressed as described above, compressed foam with a density of 0.13 g/cm ³ to 0.15 g/cm ³ Urethane is obtained.

Generally, as the density D of the material of the guide member 60 increases, the voids in the guide member 60 decrease. Therefore, when the density D of the material of the guide member 60 increases, it becomes difficult for blood to penetrate into the guide member 60. That is, when the density D of the material of the guide member 60 increases, blood easily travels along the surface of the guide member 60 without penetrating into the guide member 60. Therefore, as the density D of the material of the guide member 60 increases, the speed at which blood travels through the guide member 60 tends to increase. For these reasons, it is desirable to arrange the guide member 60 such that, for example, as the density D of the material of the guide member 60 increases, the inclination angle α of the guide member 60 becomes gentler.

FIG. 5 shows an example in which the density D of the guide member 60 is 0.13 g/cm ³ . However, for the reasons described above, when the inclination angle α of the bottom member 322 changes, it is desirable to change the density D of the material.

Furthermore, with reference to FIGS. 5 and 6, a plurality of ribs 11r extending in the vertical direction are provided on the inner surface of both side surfaces of the protruding portion 11b of the housing body 11 of this embodiment. This rib 11r has a role of rectifying the flow of blood with high viscosity.

Here, with reference to FIGS. 8 and 9, the positional relationship between the bottom member 322 located in the lower region of the suction blood filtration means 50 and the inner surface of the blood storage amount measurement region 11m of the housing body 11 will be described. 8 is a partially enlarged view of the region surrounded by VIII in FIG. 5, and FIG. 9 is a sectional view taken along the line IX-IX in FIG.

As shown in FIG. 2, the bottom member 322 located in the lower region of the suction blood filtration means 50 has a flat plate shape extending in the Z1 and Z2 directions. It faces the inner surface 11s of the flat surface 11h provided in the blood storage amount measurement region 11m facing the bottom member 322. As a result, the bottom member 322 is arranged substantially parallel to the inner surface 11s of the flat surface 11h. As a result, the gap between the flat surface 11h and the bottom member 322 becomes a substantially constant distance S1 over substantially the entire area in the Z1 and Z2 directions. In this embodiment, the shortest distance S1 between the inner surface 11s of the flat surface 11h and the bottom member 322 is 1.5 mm.

In this way, since the gap between the inner surface 11s of the flat surface 11h and the bottom member 322 is a constant distance S1, the aspirated blood that has been filtered by the guide member 60 in the bottom member 322 is spread evenly over the entire area of the flat surface. It discharges toward the inner surface 11s of 11h and comes into contact with the inner surface 11s almost simultaneously. As a result, it becomes difficult to cause disturbance in the flow of the sucked blood when it comes into contact with the inner surface 11s.

As a result, even if the liquid level of the stored blood drops and the aspirated blood after filtration falls onto the liquid level of the stored blood, the undisturbed flow of aspirated blood will continue to flow to the liquid level of the stored blood. Since the blood falls on the surface of the blood, it is possible to suppress the creation of bubbles on the surface of the stored blood.

In addition, in the said embodiment, although the distance S1 between 11 s of inner surfaces of the flat surface 11h and the bottom member 322 was 1.5 mm, the distance S1 is not limited to this numerical value. For example, the shortest distance (S1) between the inner surface 11s of the flat surface 11h and the bottom member 322 is preferably 0.05 mm to 2.0 mm. If it is smaller than 0.50 mm, blood flowing out from the guide member 60 may wrap around between the inner surface 11s of the housing body 11 and the guide member 60 and generate bubbles. If it is larger than 2.0 mm, there is a possibility that blood shed from the guide member 60 will not hit the inner surface 11s of the housing body 11.

As a result, the aspirated blood filtered by the guide member 60 in the bottom member 322 once comes into contact with the inner surface 11s, and then flows along the inner surface 11s and is poured onto the liquid surface of the stored blood, making it more effective. It is possible to suppress the creation of bubbles on the liquid surface of stored blood.

On the other hand, if the blood storage amount measurement area 11m of the housing body 11 facing the bottom member 322 is curved, the gap between the flat surface 11h and the bottom member 322 is different between the center part and both end sides. When the aspirated blood filtered by the guide member 60 reaches the blood storage amount measurement region 11m, the flow of the aspirated blood is disturbed. As a result, if the liquid level of the stored blood drops and the aspirated blood after filtration falls onto the liquid surface of the stored blood, the flow of the aspirated blood is disrupted and the aspirated blood falls onto the liquid surface of the stored blood. This promotes the creation of air bubbles on the liquid surface of the stored blood.

Therefore, as shown in this embodiment, by adopting a configuration in which the bottom member 322 is arranged substantially parallel to the flat surface 11h, it is possible to suppress the creation of air bubbles on the liquid surface of the stored blood. can.

(Blood storage form)
Below, the storage form of blood in the above-mentioned blood storage tank 1 will be explained.

When the venous blood reaches the blood inlet 12a connected to the tube of the venous blood removal line in the extracorporeal blood circulation circuit, the venous blood passes through the venous blood inlet tube 31. It is guided into the interior of the housing 10 through. Here, the tip (the other end) of the blood introduction tube 31 for venous blood extends into the inside of the protrusion 11b of the housing 10, so that the venous blood flows through the bottom of the filter member 41 for venous blood. be led to the vicinity. Then, this venous blood begins to accumulate inside the venous blood filter member 41 from the bottom upward. When this venous blood passes through the venous blood filter member 41, air bubbles contained in this venous blood are defoamed by the filter member 41. In this way, venous blood is filtered by the venous blood filter member 41, that is, the venous blood filtering means 40, and stored in the blood storage tank 1.

When the aspirated blood reaches the blood inlet, that is, the second blood inlet 12b connected to the tube of the blood removal line for aspirated blood in the extracorporeal blood circulation circuit, the aspirated blood is transferred to the blood inlet tube 32 for aspirated blood. is guided into the interior of the housing 10 through the. Then, this suctioned blood begins to accumulate in the first filter member 51 for suctioned blood. When this aspirated blood passes through the first filter member 51 for aspirated blood, relatively large foreign substances such as bone fragments and meat fragments contained in this aspirated blood are removed by this filter member. When this aspirated blood passes through the first filter member 51 for aspirated blood, relatively large air bubbles contained in this aspirated blood are broken and defoamed by this filter member.

Then, the aspirated blood that has passed through the first filter member 51 for aspirated blood begins to accumulate in the second filter member 52 for aspirated blood. Then, when this aspirated blood passes through the second filter member 52 for aspirated blood, foreign matter contained in the aspirated blood is removed by the second filter member 52. When this suctioned blood passes through the second filter member 52 for suctioned blood, air bubbles contained in this suctioned blood are defoamed by this filter member.

Specifically, when the aspirated blood that has passed through the first filter member 51 for aspirated blood begins to accumulate in the second filter member 52 for aspirated blood, the mesh cloth ( In the first filter section 52a), foreign substances and air bubbles contained in the aspirated blood are removed. Next, when the blood processing ability of the mesh cloth decreases due to clogging or the like, foreign matter and air bubbles contained in the aspirated blood are removed in the nonwoven fabric (second filter section 52b) of the second filter member 52 for aspirated blood. In this way, the aspirated blood is filtered by the first filter member 51 for aspirated blood and the second filter member 52 for aspirated blood, that is, the aspirated blood filtering means 50.

Then, the blood filtered by the suction blood filtering means 50 is guided by the guide member 60 in the direction of the blood outflow port 11c. Specifically, the blood guided by the guide member 60 is stored in the protrusion 11b of the housing 10. In this way, the aspirated blood is filtered by the aspirated blood filtration means 50 and stored in the lower storage space Sb of the blood reservoir 1.

In normal use, the lower part of the guide member 60 is immersed below the surface of the stored blood. On the other hand, as explained above, even if the liquid level of the stored blood drops and the aspirated blood after filtration falls onto the liquid level of the stored blood, the aspirated blood flow remains undisturbed. Since the liquid drops to the liquid surface of the stored blood, it is possible to suppress the creation of air bubbles on the liquid surface of the stored blood.

The embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims rather than the above description, and it is intended that all changes within the meaning and range equivalent to the claims are included.

Reference Signs List 1 blood storage tank, 10 housing, 11 housing body, 11a box-shaped part, 11b protrusion, 11c blood outflow port, 11h flat surface, 11m blood storage amount measurement area, 11p curved surface, 11r rib, 11s inner surface, 12 lid, 12a th 1 blood inlet, 12b second blood inlet, 20 filter support unit, 21 first support member, 22 second support member, 30, 31, 32 blood introduction tube, 40 venous hemofiltration means, 41 filter member, 50 suction Blood filtration means, 51 first filter member, 51a collar portion, 51b recess, 52 second filter member, 52a first filter portion, 52b second filter portion, 60 guide member, 122 frame, 122a plate portion, 122b connection member , 122c claw portion, 222 filter holding member, 222a, 222b, 222c opening, 322 bottom member, 322a support portion, 322b passage portion, 322c opening, S storage space, Sa upper storage space, Sb lower storage space.

Claims (3)

A blood reservoir for storing venous blood and/or aspirated blood,
a housing having a blood inlet and a blood outlet;
a filtration means disposed inside the housing for filtering blood flowing in from the inflow portion;
a guide member disposed between the filtration means and the outflow section and guiding the blood filtered by the filtration means in the direction of the outflow section;
A blood storage amount measuring area for measuring the amount of blood stored inside the housing is provided on a side surface of the housing,
The blood storage amount measurement area includes a flat surface in a lower area,
The filtration means includes a venous blood filtration means that filters the venous blood, and a suction blood filtration means that filters the suctioned blood,
The suction blood filtration means is disposed between the blood storage amount measurement area of the housing and the venous blood filtration means so as to face the blood storage amount measurement area,
A lower region of the suction blood filtration means is substantially parallel to the inner surface of the flat surface of the blood storage amount measurement region, and is dimensioned to allow blood to flow into the inner surface of the flat surface . The lower region of the suction blood filtration means has a bottom member having a plate-like appearance as a whole;
The blood reservoir according to claim 1, wherein the bottom member is arranged parallel to the inner surface of the flat surface. The blood reservoir according to claim 2, wherein the shortest distance between the inner surface of the flat surface and the bottom member is 0.50 mm to 2.0 mm.

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