JP2021007419A - Blood storage tank - Google Patents

Abstract

To provide a blood storage tank capable of improving a performance for capturing air bubbles in blood and suppressing residence of blood.SOLUTION: A blood storage tank 1 comprises: a housing 10 having an inner space 10a; an inflow port 21 being provided on a top part of the housing, through which blood can flow into the inner space; a filtration part 30 being stored in the inner space and having a filter 31 for filtering the blood; a conduit 60 extending into the filtration part while communicating with the inflow port, and having an opening 61 open downward; a bottom part 70 provided to face the opening of the conduit; a wall part 80 extending upward from the bottom part; and an outflow port 50 being provided on a lower part of the housing and through which the blood can flow out from the inner space. The outflow port is provided at a position different from that of the opening of the conduit in a horizontal direction.SELECTED DRAWING: Figure 3

Description

The present invention relates to a blood storage tank.

When performing surgical treatment for congenital heart disease, ischemic heart disease, macrovascular disease, etc., the heart is often stopped and surgery is performed, but during that time, extracorporeal for the purpose of temporarily substituting the functions of the heart and lungs. An artificial heart-lung machine containing a circulatory circuit is used. The artificial cardiopulmonary system is provided with a blood storage tank for temporarily storing blood such as venous blood drawn from the patient's veins and intracardiac blood (suctioned blood) overflowing in the surgical field (for example, the following). See Patent Document 1). The blood that has flowed into the blood storage tank passes through a filter to remove foreign substances and air bubbles, then flows out of the blood storage tank from the outflow port, passes through an artificial lung, and is returned to the patient.

Japanese Unexamined Patent Publication No. 2003-111835

However, in the blood storage tank of Patent Document 1, when the blood flow rate is large and the flow velocity is high, the pressure applied to the filter when the blood passes through the filter increases, and the performance of capturing air bubbles deteriorates. there is a possibility. Further, when the amount of blood stored in the blood storage tank is excessively large, the blood may stay near the liquid surface for a long time.

An object of the present invention is to provide a blood storage tank capable of suppressing blood retention while improving the ability to capture air bubbles in blood.

A blood storage tank that achieves the above object is provided in a housing having an internal space, a filtration unit having a filter housed in the internal space and filtering blood, and an upper part of the housing, and blood flows into the internal space. A possible inflow port, a conduit that communicates with the inflow port and extends into the filtration section and has an opening that opens downward, and a bottom portion of the conduit that is provided to face the opening. It has a wall portion extending upward from the bottom portion and an outflow port provided in the lower part of the housing and capable of flowing blood from the internal space, and the outflow port is provided with the opening of the conduit. It is placed in different positions in the horizontal direction.

According to the blood storage tank configured as described above, the blood flowing out from the opening of the conduit can be prevented from directly colliding with the filter by flowing upward. As a result, the pressure applied to the filter from the bloodstream can be reduced to improve the performance of capturing air bubbles. Further, after the blood flows upward, it can be induced to swirl in the blood reservoir by flowing to the outflow port side arranged at a different position in the horizontal direction from the opening of the conduit. As a result, the blood stored in the blood storage tank can be agitated. As a result, it is possible to suppress the retention of blood in the blood storage tank while improving the performance of capturing air bubbles in the blood.

It is a perspective view which showed the schematic structure of the blood storage tank which concerns on one Embodiment of this invention. It is a perspective view which shows the internal structure of the blood storage tank which concerns on one Embodiment of this invention. It is a side sectional view of the blood storage tank which concerns on one Embodiment of this invention. It is sectional drawing which shows the part of the blood storage tank shown in FIG. 3 enlarged. It is sectional drawing of the blood storage tank for demonstrating the flow of blood. It is sectional drawing of the blood storage tank for demonstrating the flow of blood. It is sectional drawing of the blood storage tank for demonstrating the flow of blood. It is a figure for demonstrating the flow of blood, and is the cross-sectional view along line 8-8 of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. The following description does not limit the technical scope and meaning of terms described in the claims. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation and may differ from the actual ratios.

[Overall composition of blood storage tank]
FIG. 1 is a perspective view showing a schematic configuration of a blood storage tank 1 according to an embodiment of the present invention, FIG. 2 is a perspective view showing an internal configuration of the blood storage tank 1, and FIG. 3 is a side sectional view of the blood storage tank 1. , FIG. 4 is an enlarged cross-sectional view showing a part of the blood storage tank shown in FIG. The XYZ Cartesian coordinate system is shown in the figure for convenience of the following description. The X-axis and Y-axis indicate horizontal axes, and the Z-axis indicates vertical axes. The X-axis direction is the "front-back direction" of the blood storage tank 1, and the Y-axis direction is the "width direction" of the blood storage tank 1. The side facing the X-axis arrow is referred to as the "front side", and the side opposite to the X-axis arrow is referred to as the "back side".

The blood storage tank 1 according to the present embodiment has a blood storage tank (venous reservoir) for temporarily storing venous blood removed from a patient's vein and intracardiac blood (suction) sucked from the surgical field (outside the heart). It is an integrated blood storage tank that integrates a blood storage tank (cardiotomy reservoir) that temporarily stores blood).

The blood storage tank 1 is incorporated into an extracorporeal circulation circuit used in cardiac surgery, for example, and is used to filter and defoam venous blood and intracardiac blood to temporarily store blood.

As shown in FIGS. 1 and 2, the blood storage tank 1 is provided in a housing 10 having an internal space 10a (blood storage space) for storing blood, and an inflow that is provided above the housing 10 and allows blood to flow into the internal space 10a. A port 20, a venous blood filtering section 30 (corresponding to the filtering section) housed in the internal space 10a and filtering venous blood, a cardiotomy section 40 for filtering intracardiac blood, and a cardiotomy section 40 provided at the lower part of the housing 10. It has an outflow port 50 capable of outflowing blood from the internal space 10a.

The inflow port 20 has a venous blood flow inflow port 21 into which venous blood flows in and an intracardiac blood flow inflow port 22 into which intracardiac blood flows.

As shown in FIG. 3, the blood storage tank 1 has a conduit 60 having an opening 61 that communicates with the venous blood flow inlet port 21 and extends into the venous blood filtration section 30 and opens downward, and the conduit 60. It further has a bottom portion 70 provided so as to face the opening portion 61 of the above, and a wall portion 80 extending upward from the bottom portion 70. The outflow port 50 is arranged at a different position in the horizontal direction from the opening 61 of the conduit 60.

The bottom 70 and the wall 80 are formed in a cup shape. The blood flowing out of the conduit 60 collides with the bottom 70 and is guided by the wall 80 to flow upward. The bottom 70 and the wall 80 are preferably arranged so as to be continuous without gaps, but may be arranged with gaps to such an extent that an upward flow of blood can be formed.

In the present embodiment, an example will be described in which the bottom portion 70 is integrally formed with the bottom portion of the housing 10, and the wall portion 80 is integrally formed with the venous blood filtration unit 30.

Hereinafter, the configuration of each part of the blood storage tank 1 will be described in detail.

(housing)
As shown in FIG. 1, the housing 10 has a housing main body 11 and a lid 12 mounted on the upper part of the housing main body 11.

The housing body 11 has a box shape with an open top. The housing main body 11 includes an accommodating portion 111 forming an upper portion of the internal space 10a, and a projecting portion 112 in which a part of the front surface side of the accommodating portion 111 projects downward. The accommodating portion 111 forms a blood storage space on the side where blood flows in. The protrusion 112 forms a blood storage space on the side where blood flows out.

As shown in FIG. 3, the protruding portion 112 includes an inverted conical upper portion 112U formed so that the cross-sectional area decreases downward, and a tubular lower portion 112L extending downward from the upper end. It is configured in a funnel shape.

With reference to FIG. 4, the bottom 112a of the protrusion 112 (hereinafter referred to as “the bottom 112a of the housing 10”) has a bottom 70 provided so as to face the opening 61 of the conduit 60. The bottom portion 70 includes a groove portion 71 into which the lower end of the wall portion 80 of the venous blood filtration portion 30 can be fitted, a convex portion 72 in which a portion located on an extension line of the central axis O of the conduit 60 projects upward, and a convex portion 72. It has a recess 73 whose outer circumference is recessed downward. The groove 71 is formed in an annular shape so as to follow the shape of the lower end of the venous blood filtration section 30. The convex portion 72 and the concave portion 73 have a curved shape in the cross-sectional view shown in FIG. As a result, when the blood flowing out of the conduit 60 collides with the bottom portion 70, the blood flows along the shapes of the convex portion 72 and the concave portion 73, so that the blood can be smoothly guided upward.

As shown in FIGS. 1 and 3, the lid 12 is arranged so as to cover the upper opening of the housing body 11. The lid 12 is provided with a venous blood flow inlet port 21 and an intracardiac blood flow inlet port 22. In addition to the venous blood flow inlet port 21 and the intracardiac blood flow inlet port 22, the lid body 12 is injected with a bent blood port capable of inflowing bent blood into the internal space 10a, a chemical solution for mixing the drug solution, and the like into the blood. A port, an exhaust port for adjusting the pressure in the blood storage tank 1, a pressure adjusting valve, or the like may be provided.

The constituent material of the housing 10 is not particularly limited, and examples thereof include polycarbonate, acrylic resin, polyethylene terephthalate, polyethylene, polypropylene, polystyrene, polyvinyl chloride, acrylic-styrene copolymer, acrylic-butadiene-styrene copolymer and the like. Be done.

Further, the housing 10 is preferably substantially transparent, translucent, and colored and transparent to the extent that the amount and state of blood stored in the internal space 10a can be visually confirmed.

(Venous blood flow port and intracardiac blood flow port)
A tube of a blood removal line for removing blood from a patient's vein is connected to the venous blood flow inlet port 21. A suction line tube for sucking intracardiac blood from the surgical field is connected to the intracardiac blood flow inlet port 22.

(conduit)
As shown in FIG. 2, the conduit 60 is formed of a hollow tubular member. With reference to FIG. 3, the conduit 60 includes a lumen 60a extending in the vertical direction and guiding the blood flowing in from the venous blood flow inlet port 21 downward, and an opening 61 provided at the lower end of the lumen 60a. Has. The conduit 60 is arranged so as to extend from the venous blood flow inlet port 21 to the protrusion 112 of the housing body 11.

With reference to FIG. 4, the opening 61 of the conduit 60 is located above the bottom 112a of the housing 10 by a height H1. The height H1 is preferably set to 3 to 5 mm.

(Venous blood filter)
As shown in FIGS. 2 and 3, the venous blood filtration unit 30 has a filter 31 and a support member 32 that supports the filter 31. The venous blood filtration unit 30 has a tubular shape having an elliptical or circular cross-sectional shape.

The support member 32 is formed in a grid pattern having a plurality of openings on its side surface. The support member 32 has a wall portion 80 extending upward from the bottom portion 70 (in this embodiment, the bottom portion 112a of the housing 10) at the lower end thereof. The wall portion 80 is arranged so as to surround the conduit 60. As shown in FIG. 4, the wall portion 80 (lower end of the support member 32) is fitted in the groove portion 71 of the bottom portion 70.

With reference to FIG. 4, the height H2 (length along the vertical direction) of the wall portion 80 is preferably set to 10 to 15 mm. By setting the height H2 of the wall portion 80 higher than the height H1, the wall portion 80 is configured to extend to a position higher than the opening 61 of the conduit 60. Therefore, a flow path 80a surrounded by the wall portion 80 and the conduit 60 is formed at a portion where the wall portion 80 and the conduit 60 overlap in the vertical direction. The flow path 80a can more reliably guide the blood flowing out of the opening 61 of the conduit 60 upward. On the other hand, if the height H2 of the wall portion 80 is too high, the upward flow of blood becomes too strong. As a result, the blood passing through the filter 31 is extremely concentrated on the upper part of the venous blood filtration unit 30, and the pressure applied to the filter 31 becomes non-uniform. From such a viewpoint, it is preferable to set the height H2 of the wall portion 80 in the above range.

The filter 31 is inserted (insert molded) into the opening 61 of the support member 32 to be integrally formed with the support member 32. The filter 31 is not limited to a configuration that is integrally formed with the support member 32, and may be formed in a bag shape that is separate from the support member 32, for example. In this case, the filter 31 is preferably arranged so as to cover the outside of the support member 32 from the viewpoint of preventing the formation of thrombi and the mixing of foreign substances outside the filter 31.

As the filter 31, for example, a known filtration filter using a woven fabric or a non-woven fabric having a large number of fine openings can be appropriately selected and used. The constituent material of the filter 31 is not particularly limited, but is, for example, a polymer material such as polyester such as PET or PBT, polyamide, Tetron (registered trademark), rayon, polypropylene, polyolefin such as polyethylene, polyvinyl chloride, or the like. A combination of two or more of these can be mentioned. The opening diameter of the filter 31 is not particularly limited, but is preferably 30 μm to 200 μm. If the opening diameter is larger than this numerical range, the ability to capture air bubbles deteriorates. If the opening diameter is smaller than this numerical range, the passage resistance when blood passes through the filter 31 increases, the filter 31 is likely to be clogged, and the liquid level inside the venous blood filtration unit 30 becomes high. A hold-up phenomenon that rises above the outside may occur. From this point of view, it is preferable to set the opening diameter of the filter 31 in the above range.

The venous blood filtration unit 30 may be provided with a defoaming agent, or the filter 31 may be coated with silicone or the like to provide a defoaming function for air bubbles.

(Cardiotomy Department)
As shown in FIG. 3, the cardiotomy portion 40 has a bag-shaped filter 41 and a defoaming member 42 housed in the filter 41. As the material for forming the filter 41, the same material as the filter 31 of the venous blood filtration unit 30 described above can be used. The defoaming member 42 is not particularly limited as long as it has a function of breaking bubbles when it comes into contact with bubbles, and for example, a foam carrying a defoaming agent such as silicone can be used.

(Outflow port)
As shown in FIGS. 3 and 4, the outflow port 50 is arranged at a different position in the horizontal direction on the back side with respect to the opening 61 of the conduit 60. Here, "arranging at different positions in the horizontal direction" means arranging the blood storage tank 1 at a position where the outflow port 50 and the opening 61 of the conduit 60 do not overlap when viewed from above. (See FIG. 8). As a result, the flow path of blood flowing out from the opening 61 of the conduit 60 and the flow path of blood flowing out of the outflow port 50 are not continuous in the vertical direction but are offset in the horizontal direction. As long as the opening 61 of the conduit 60 is arranged at a position different from the outflow port 50 in the horizontal direction, the portion above the opening 61 of the conduit 60 partially overlaps the outflow port 50 in the horizontal direction. It may be arranged.

Next, the flow of blood in the blood storage tank 1 will be described with reference to FIGS. 5 to 8. 5 and 7 are cross-sectional views of the blood storage tank 1 viewed from the width direction in order to explain the flow of blood (mainly venous blood), and FIG. 8 is a liquid of blood stored in the housing 10. It is sectional drawing which looked at the blood storage tank 1 from the upper direction in order to explain the flow of blood near the surface L. The arrows in the figures of FIGS. 5 to 8 indicate the blood flow.

The intracardiac blood sucked from the surgical field of the patient passes through the intracardiac blood flow inlet port 22 and flows into the cardiotomy section 40. The bubbles mixed in the intracardiac blood come into contact with the defoaming member 42 and burst. The intracardiac blood in the cardiotomy section 40 passes through the defoaming member 42 and the filter 31 of the cardiotomy section 40. As a result, foreign substances such as meat pieces, fat, and blood clots and air bubbles contained in the intracardiac blood are removed. After that, the intracardiac blood is stored in the internal space 10a of the housing body 11.

As shown in FIG. 5, the venous blood bleeding from the patient's vein passes through the venous blood flow inlet port 21 and the conduit 60 in order, and flows out from the opening 61 of the conduit 60. After that, it collides with the bottom 70 and is guided by the wall 80 to flow upward.

Then, as shown in FIG. 6, the venous blood that has flowed upward passes through the filter 31 of the venous blood filtration unit 30. At this time, the venous blood flows upward, so that the blood flow rate through the filter 31 near the liquid level L of the blood stored in the housing 10 can be increased. Further, since the blood flow is not locally concentrated in the vicinity of the bottom 70 (lower side of the blood storage tank 1) where the venous blood collides, but is dispersed upward, the pressure applied to the filter 31 can be made uniform. .. This makes it possible to improve the ability to capture air bubbles in the blood.

After that, venous blood flows to the outflow port 50 side as shown in FIG. The outflow port 50 is arranged at a different position in the horizontal direction from the opening 61 of the conduit 60. Therefore, the venous blood that has passed through the filter 31 is sucked in the downward oblique direction by the suction force (negative pressure) of the outflow port 50, and swirls around the venous blood filtration unit 30 as shown in FIG. It flows. Due to the swirling flow of the venous blood, the vicinity of the liquid level L of the blood stored in the housing 10 is agitated. Further, since the venous blood filtering unit 30 has a tubular shape having an elliptical or circular cross-sectional shape, it is easy to induce a blood flow that swirls around the venous blood filtering unit 30 after the blood has passed through the filter 31. Become.

Intracardiac blood sucks blood that has overflowed into the surgical field (outside the heart), whereas venous blood is removed from the patient's vein for extracorporeal circulation. Therefore, most of the blood flowing into the blood storage tank 1 is venous blood. Therefore, the blood flow in the housing 10 is mainly formed by the flow of venous blood flowing in from the conduit 60. Therefore, by adjusting the flow of venous blood, it is possible to induce a flow of stirring the blood near the liquid level L of the blood stored in the housing 10.

If the outflow port is located directly below the opening 61 of the conduit 60, the venous blood collides with the bottom 70 and is guided by the wall 80 to flow upwards and then downwards. For this reason, most of the venous blood is concentrated on the bottom 112a of the housing 10. As a result, blood flow is not formed near the liquid level L of the blood stored in the housing 10 (upper side of the blood storage tank 1), and there is a possibility that retention may occur.

In particular, since intracardiac blood comes into contact with air more often than venous blood and is activated, thrombus is likely to be formed when intracardiac blood stays for a long time.

According to the blood storage tank 1 according to the present embodiment, since it is possible to induce a flow of stirring the blood near the liquid level L of the blood stored in the housing 10, it is possible to suppress the retention of blood. it can.

As described above, the blood storage tank 1 according to the present embodiment is provided with a housing 10 having an internal space 10a and a venous blood flow inlet port 21 (inflow port) provided above the housing 10 and capable of flowing blood into the internal space 10a. ), The venous blood filtering unit 30 (filtering unit), which is housed in the internal space 10a and has a filter 31 for filtering blood, and extends into the venous blood filtering unit 30 in communication with the venous blood inlet port 21. A conduit 60 having an opening 61 that opens downward, a bottom 70 provided so as to face the opening 61 of the conduit 60, a wall portion 80 extending upward from the bottom 70, and a housing 10. It has an outflow port 50 provided at the bottom and capable of outflowing blood from the internal space 10a. The outflow port 50 is arranged at a different position in the horizontal direction from the opening 61 of the conduit 60.

According to the blood storage tank 1 configured as described above, it is possible to prevent the blood from directly colliding with the filter 31 by the blood flowing out from the opening 61 of the conduit 60 flowing upward. As a result, the pressure applied to the filter from the bloodstream can be reduced to improve the performance of capturing air bubbles. Further, after the blood flows upward, it can be induced to swirl in the blood storage tank 1 by flowing to the outflow port 50 side arranged at a different position in the horizontal direction from the opening 61 of the conduit 60. As a result, the blood stored in the blood storage tank 1 can be agitated. As a result, it is possible to suppress the retention of blood in the blood storage tank 1 while improving the performance of capturing air bubbles in the blood.

Further, the wall portion 80 extends to a position higher than the opening 61 of the conduit 60. Therefore, a flow path 80a surrounded by the wall portion 80 and the conduit 60 is formed at a portion where the wall portion 80 and the conduit 60 overlap in the vertical direction. The flow path 80a can more reliably guide the blood flowing out of the opening 61 of the conduit 60 upward.

Further, the venous blood filtration unit 30 has a tubular shape having an elliptical or circular cross-sectional shape. Therefore, after the blood has passed through the filter 31, it becomes easy to induce a blood flow that swirls around the venous blood filtration unit 30. As a result, the retention of blood in the blood storage tank 1 can be suppressed.

Further, since the bottom portion 70 is integrally formed with the bottom portion 112a of the housing 10, blood that collides with the bottom portion 70 does not flow downward. Thus, the blood moves upward and then flows towards the outflow port 50. As a result, the blood flow in the blood storage tank 1 is further agitated, so that retention can be suppressed more reliably.

Although the blood storage tank according to the present invention has been described above through the embodiments, the present invention is not limited to each configuration described in the specification, and may be appropriately modified based on the description of the scope of claims. It is possible.

For example, the outflow port of the above-described embodiment has been described as being arranged at different horizontal positions on the back side with respect to the opening of the conduit, but the offset direction is particularly limited as long as it is horizontal. However, it may be in any direction around the conduit (for example, the front direction (X-axis direction in FIG. 1) and the width direction (Y-axis direction in FIG. 1)).

Further, the shape of the venous blood filtration unit is not limited to the tubular shape having an elliptical or circular cross-sectional shape as in the above-described embodiment, and may be, for example, a polygonal cross-sectional shape.

Further, the wall portion is configured to be integrally formed with the support member of the venous blood filtering portion, but the present invention is not limited to this, and the wall portion may be configured separately from the venous blood filtering portion.

Further, the bottom portion is configured to be integrally formed with the bottom portion of the housing, but the present invention is not limited to this, and for example, the bottom portion may be configured separately from the bottom portion of the housing and integrally with the support member of the venous blood filtration portion. Good.

Further, the shape of the bottom portion is not limited to the shape having convex portions and concave portions, and may have, for example, a flat shape.

Further, the venous blood filtration unit is not limited to the above-described embodiment, and each portion constituting the venous blood filtration unit can be replaced with an arbitrary configuration capable of exhibiting the same function. For example, the filter may be formed in a bag shape without the support member.

Further, the cardiotomy unit is not limited to the above-described embodiment, and each unit constituting the cardiotomy unit can be replaced with an arbitrary configuration capable of exhibiting the same function. For example, the filter and the defoaming member of the cardiotomy portion do not have to have a bag shape as in the above embodiment, but may have a cylindrical shape, for example.

Further, in the above-described embodiment, the venous blood reservoir into which venous blood flows and the intracardiac blood reservoir into which intracardiac blood flows are integrated, but the present invention can be applied. The blood storage tank is not limited to this, and can be applied to a known blood storage tank. For example, it may be a venous blood reservoir in which venous blood flows in without intracardiac blood flowing in.

1 blood storage tank,
10 housing,
10a interior space,
11 Housing body,
111 containment unit,
112 protrusion,
112a The bottom of the protrusion (bottom of the housing),
12 lid,
20 inflow port,
21 Venous blood flow inlet port (inflow port),
22 Intracardiac blood flow inlet port,
30 Venous blood filtration part (filtration part),
31 filters,
32 Support member,
40 Cardiotomy Club,
41 filters,
42 Defoaming member,
50 outflow ports,
60 conduits,
61 Conduit opening,
70 bottom,
80 wall part.

Claims (4)

A housing with an internal space and
An inflow port provided on the upper part of the housing and capable of inflowing blood into the internal space,
A filtration unit housed in the internal space and having a filter for filtering blood,
A conduit that communicates with the inflow port and extends into the filtration section and has an opening that opens downward.
With a bottom provided to face the opening of the conduit
A wall portion extending upward from the bottom and
An outflow port provided at the bottom of the housing and capable of outflowing blood from the internal space,
Have,
The outflow port is a blood storage tank located at a different position in the horizontal direction from the opening of the conduit. The blood storage tank according to claim 1, wherein the wall portion extends at a position higher than the opening of the conduit. The blood storage tank according to claim 1 or 2, wherein the filtration unit has a tubular shape having an elliptical or circular cross-sectional shape. The blood storage tank according to any one of claims 1 to 3, wherein the bottom portion is integrally formed with the bottom portion of the housing.