JP2021074026A - Blood storage tank - Google Patents

Abstract

To provide a blood storage tank which can suppress a vortex flow generated in blood flowing out of an inner tube.SOLUTION: A blood storage tank 1 includes a housing 10 having an interior space 10a, a filtering part 30 which is equipped with a filter body 31 for filtering blood and is stored in the interior space of the housing, and an inner tube 60 which is arranged on an inner peripheral side of the filtering part 30 and forms a filtering space 70 between the filtering part 30 and the inner tube. The inner tube includes a lumen 60a for introducing the blood and a vortex flow suppressing part 65 which is arranged in the periphery of the lumen and suppresses a vortex flow generated in the blood flowing in the filtering space. In a cross section perpendicular to a longitudinal direction of the filtering part, a configuration of an inner surface 31a of the filter body and a configuration of an outer surface 62a of the inner tube 60 are similar to each other in the shapes, and the vortex flow suppressing part is formed of a tube wall of the inner tube.SELECTED DRAWING: Figure 4

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. A heart-lung machine containing a circulatory circuit is used. The artificial cardiopulmonary system is equipped with a blood storage tank for temporarily storing blood such as venous blood drawn from the patient's veins and intraoperative 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

In the blood storage tank described in Patent Document 1, the cross-sectional shape of the outer surface of the inner tube through which blood passes before being filtered by the filter body (filtration membrane) (the shape of the cross section orthogonal to the longitudinal direction of the inner tube) is blood. It narrows toward the flow direction (the tip side of the inner pipe). The blood that has passed through the inner tube flows into the filtration space formed between the outer surface of the inner tube and the filtration section having the support member to which the filter body is assembled, and then passes through the filter body and is filtered. .. For example, when the cross-sectional shape of the inner pipe is narrowed on the tip side as described above, the cross-sectional shape of the filtration space (cross-sectional shape of the flow path) is different in each part in the longitudinal direction of the inner pipe. Therefore, when the blood flowing out from the opening provided at the tip of the inner tube flows from the vicinity of the opening toward the base end side of the inner tube (downstream side through which the filtered blood flows), the flow thereof. Is disturbed, and a vortex may occur. The formation of vortices in the blood increases the risk of bubbles. As a result, there is a risk that air bubbles cannot be sufficiently removed from the blood.

An object of the present invention is to provide a blood storage tank capable of suppressing the generation of a vortex in the blood flowing out of the inner tube.

The blood storage tank that achieves the above object includes a housing having an internal space and a filter body for filtering blood, and is arranged in the filtration unit housed in the internal space and the inner peripheral side of the filtration unit. It has an inner tube that forms a filtration space between the inner tube and the inner tube, which is arranged around the inner tube for guiding the blood and the inner tube, and the inner tube and the filtration portion. The contour of the inner surface of the filter body and the contour of the outer surface of the inner tube in a cross section orthogonal to the longitudinal direction of the filtration section, which has a vortex suppressing portion that suppresses the generation of vortex in the blood between them. Is a blood storage tank having a substantially similar shape to and that the vortex suppressing portion is formed by the tube wall of the inner tube.

According to the blood storage tank configured as described above, the vortex suppression unit can suppress the generation of vortex in the blood flowing out from the inner tube to the filtration space.

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 side view which shows the internal structure of the blood storage tank which concerns on one Embodiment of this invention simplified. It is the schematic sectional drawing of the blood storage tank along the arrow 3A-3A line shown in FIG. It is the schematic sectional drawing of the blood storage tank along the arrow 4A-4A line shown in 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.

1 to 4 are views provided for explaining the blood storage tank 1 according to the embodiment of the present invention. The X-axis attached to each figure indicates the "anterior-posterior direction" of the blood storage tank 1, the Y-axis indicates the "width direction" of the blood storage tank 1, and the Z-axis indicates the "height direction" of the blood storage tank 1. ..

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 to 3, the blood storage tank 1 includes a housing 10 having an internal space 10a and a filter body 31 for filtering blood, and is housed in the internal space 10a of the housing 10. And an inner pipe 60 which is arranged on the inner peripheral side of the filtration unit 30 and forms a filtration space 70 between the filtration unit 30 and the filtration unit 30.

As shown in FIGS. 1 to 3, the housing 10 has a housing body 11 in which an internal space 10a is formed, and a lid 12 attached to the upper side of the housing 10.

The lid 12 of the housing 10 is provided with an inflow port 20 for allowing blood to flow into the internal space 10a. The bottom of the housing 10 is provided with an outflow port 50 that allows the filtered blood to flow out of the internal space 10a.

In addition to the venous blood flow inlet port 21 and the intracardiac blood flow inlet port 22, the lid 12 has a vent blood port capable of inflowing vent blood into the internal space 10a, a drug solution injection port for mixing a drug solution or the like into blood, and a drug solution injection port. An exhaust port, a pressure adjusting valve, or the like for adjusting the pressure in the blood storage tank 1 may be provided.

As shown in FIG. 2, 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 in which intracardiac blood flows in.

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.

As shown in FIG. 3, the inner tube 60 includes a lumen 60a through which blood can flow. The lumen 60a of the inner tube 60 communicates with the venous blood flow inlet port 21. At the tip of the inner tube 60 (on the bottom side of the housing 10), an opening 61 communicating with the lumen 60a of the inner tube 60 is formed.

As shown in FIGS. 2 and 3, the filtration unit 30 includes a support member 32 that supports the filter body 31. The support member 32 is formed in a grid pattern having a plurality of openings on its side surface. A wall portion 80 that is fixed to the housing body 11 by fitting or the like is provided at the tip end portion (lower end portion of FIG. 2) of the support member 32.

The filter body 31 can be attached to the opening (not shown) of the support member 32 by, for example, insert molding. The filter body 31 is not limited to the structure formed integrally with the support member 32, and may be formed in a bag shape separate from the support member 32, for example. In this case, the filter body 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 body 31.

As the filter body 31, for example, a known filtering 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 body 31 is not particularly limited, and is, for example, polyester such as PET and PBT, polyamide, tetron, rayon, polypropylene, polyolefin such as polyethylene, and polymer materials such as polyvinyl chloride, or among these. A combination of two or more of the above can be mentioned.

The specific configuration of the filter body 31 such as the opening, the thickness, and the opening area is not particularly limited. Further, the filtration unit 30 may be provided with a defoaming agent, or the filter body 31 may be coated with silicone or the like to provide a defoaming function for air bubbles.

As shown in FIG. 2, a filtration space 70 is provided between the filtration unit 30 and the inner pipe 60. The blood flowing from the venous blood flow inlet port 21 flows into the lumen 60a of the inner tube 60 (see arrow a1 in FIGS. 2 and 3), and when it reaches the opening 61 of the inner tube 60, the blood flows through the opening 61. It flows out to the outside of the inner pipe 60. The blood flowing out from the opening 61 of the inner tube 60 collides with the bottom portion 11a of the housing body 11 and is guided to spread outward with respect to the inner tube 60. Blood flows into the filtration space 70 while flowing outward of the inner tube 60. The blood that has flowed into the filtration space 70 flows upward through the filtration space 70 as the volume of blood that flows into the lumen 60a of the inner tube 60 increases through the venous blood flow inlet port 21. The blood that has flowed into the filtration space 70 is filtered by passing through the filter body 31 included in the filtration unit 30 (see arrow a2 in FIGS. 2 and 3). The filtered blood flows toward the outflow port 50 provided on the bottom side of the housing 10 (see FIG. 2).

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, and acrylic-butadiene-styrene copolymer. 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.

As shown in FIG. 2, a cardiotomy portion 40 is arranged in the internal space 10a of the housing 10. As the cardiotomy unit 40, for example, a known one having a bag-shaped filter or a defoaming member housed in the filter can be used.

As shown in FIG. 2, the intracardiac blood sucked from the patient's surgical field passes through the intracardiac blood flow inlet port 22 and flows into the cardiotomy section 40 (see arrow b1 in FIG. 2). The air bubbles mixed in the intracardiac blood come into contact with the defoaming member included in the cardiotomy portion 40 and burst. The intracardiac blood in the cardiotomy section 40 passes through the defoaming member and the filter included in 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.

Next, the eddy current suppression unit 65 will be described.

As shown in FIGS. 3 and 4, the inner pipe 60 includes a vortex suppressing portion 65 arranged around the lumen 60a of the inner pipe 60. The vortex suppression unit 65 has a function of suppressing the generation of vortex in the blood flowing through the filtration space 70 (blood flowing upward in the filtration space 70). In the blood storage tank 1 according to the present embodiment, the vortex suppressing portion 65 is formed by the tube wall (tube meat) of the inner tube 60.

FIG. 4 shows a cross section (a cross section orthogonal to the longitudinal direction of the filtration unit 30) along the line 4A-4A of FIG. In the cross section shown in FIG. 4, the contour of the inner surface 31a of the filter body 31 and the contour of the outer surface 62a of the inner tube 60 have substantially similar shapes. Therefore, the blood storage tank 1 can appropriately maintain the clearance between the inner surface 31a of the filter body 31 and the outer surface 62a of the inner tube 60. Further, as a result, the blood storage tank 1 has a cross-sectional shape of the filtration space 70 formed between the inner tube 60 and the filter body 31 in a cross section orthogonal to the longitudinal direction of the filtration section 30, and the cross-sectional shape of the filtration space 70 is changed in the longitudinal direction of the filtration section 30. The shape can be made substantially constant (in the vertical direction of FIG. 2).

The description of "abbreviation" in the present specification does not mean only that the two objects to be compared are strictly "identical". For example, shape differences based on manufacturing tolerances are included in the "omitted" range.

Since the cross section of the filtration space 70 has a substantially constant shape in the longitudinal direction of the filtration section 30 as described above, the blood flowing upward through the filtration space 70 as a flow path is filtered in the longitudinal direction of the filtration section 30. Flow turbulence due to the non-uniform cross-sectional shape of the space 70 is less likely to occur. Therefore, it is possible to preferably prevent the generation of a vortex in the blood flowing through the filtration space 70.

Further, the portion of the inner pipe 60 that forms the vortex suppressing portion 65 is formed to be thicker than the filtration portion 30 (filter body 31 and support member 32). The inner pipe 60 on which the vortex suppressing portion 65 is formed serves as a spacer for reducing the internal volume of the filtration space 70. Therefore, in the blood storage tank 1, the internal volume of the filtration space 70 can be reduced by the vortex suppression unit 65 formed in the inner tube 60 without reducing the area of the filter body 31 included in the filtration unit 30. This makes it possible to prevent the difference between the volume of the lumen 60a of the inner tube 60 and the internal volume of the filtration space 70 from becoming excessively large. Then, while blood is flowing through the inner tube 60 and the filtration space 70, the lumen of the inner tube 60 is caused by the volume difference between the volume of the inner tube 60 a and the internal volume of the filtration space 70. It is possible to prevent a large pressure difference between the 60a and the filtration space 70. As a result, the inner pipe 60 in which the vortex suppressing portion 65 is formed can suitably prevent the so-called hold-up phenomenon from occurring.

The contour of the inner surface 31a of the filter body 31 can be formed, for example, in a substantially elliptical shape in the cross section shown in FIG. Further, the contour of the outer surface 62a of the inner pipe 60 can be formed, for example, in a substantially elliptical shape in the cross section shown in FIG. Since the contour of the inner surface 31a of the filter body 31 and the contour of the outer surface 62a of the inner tube 60 are formed in an elliptical shape, the blood flowing upward in the filtration space 70 can be collected from the contour of the inner surface 31a of the filter body 31 and the inner tube 60. It moves smoothly along the outer surface 62a. Although not shown, the support member 32 that supports the filter body 31 is formed to have substantially the same cross-sectional shape as the filter body 31.

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, in the description of the embodiment, a blood storage tank in which a venous blood storage tank into which venous blood flows and an intracardiac blood storage tank in which intracardiac blood flows are integrated has been described, 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.

Further, the contour of the outer surface of the inner tube and the contour of the inner surface of the filter body are not limited to the elliptical shape.

1 Blood storage tank,
10 housing,
10a interior space,
11 Housing body,
11a The bottom of the housing body,
30 Filtration section,
31 filter body,
31a Inner surface of filter body,
32 Support member,
40 Cardiotomy Club,
60 inner tube,
60a Inner tube lumen,
61 opening,
62a Outer surface of the lumen,
65 Swirl flow suppression part (inner pipe wall),
70 filtration space,
80 wall part.

Claims (3)

A housing with an internal space and
A filter body for filtering blood is provided, and a filtration unit housed in the internal space and
It has an inner tube that is arranged on the inner peripheral side of the filtration section and forms a filtration space with the filtration section.
The inner tube has a lumen for guiding the blood and a vortex suppressing portion which is arranged around the lumen and suppresses the generation of vortex in the blood flowing through the filtration space.
In the cross section orthogonal to the longitudinal direction of the filtration portion, the contour of the inner surface of the filter body and the contour of the outer surface of the inner tube have substantially similar shapes.
The vortex suppressing portion is a blood storage tank formed by the tube wall of the inner tube. The contour of the inner surface of the filter body has a substantially elliptical shape in a cross section orthogonal to the longitudinal direction of the filtration portion.
The blood storage tank according to claim 1, wherein the contour of the outer surface of the inner tube has a substantially elliptical shape in a cross section orthogonal to the longitudinal direction of the filtration portion. The blood storage tank according to claim 1 or 2, wherein the portion of the inner tube wall that forms the vortex suppressing portion is formed to be thicker than the filtration portion.

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