JPH0126707B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a blood reservoir for use in a heart-lung machine during open heart surgery. More specifically, the present invention relates to a blood reservoir capable of storing intracardiac blood and venous blood.

[Prior Art] An artificial heart-lung circuit used in open-heart surgery uses a blood reservoir that filters and defoams intracardiac blood collected by suction from the surgical field and stores it. The blood processed in this blood reservoir is stored in a second blood reservoir along with blood removed from the vena cava, and is sent to a heart-lung machine by a blood pump, oxygenated, and returned to the patient. Generally, the former blood storage tank is
As disclosed in publications such as -58159 and 60-103968, filters for filtering foreign particles such as micro tissue fragments and micro aggregates contained in blood and antifoaming for defoaming. The material is integrated into the device, and by passing blood through it, foreign particles can be continuously removed and foam can be defoamed. Then, the filtered and defoamed blood is temporarily stored in the lower part of the housing and is led out from the bottom.

[Problems to be Solved by the Invention] Conventionally, as mentioned above, since blood is stored in two blood reservoirs, the priming volume (blood filling amount) in the extracorporeal circulation circuit is inevitably large. This caused the problem of an increase in the amount of blood transfusion. The present invention has been made to solve this problem, and its object is to provide a functionally superior blood reservoir that requires less priming volume.

[Means for Solving the Problems] The above-mentioned object is achieved by integrating two blood reservoirs into a specific configuration. That is, the present invention provides an intracardiac blood flow inlet in the upper part, and a venous blood flow inlet 19 and a blood outlet in the lower part in a hollow body housing in which the venous blood flow inlet is located above the blood outlet. , a cylindrical filtration and defoaming section is provided above and a blood storage section is provided below, and an air flow path that communicates with the blood storage section and an air vent provided above the housing and is separated from the filtration and defoaming section is filtered and extinguished. A guiding part is provided vertically in the substantially center of the foam part and guides the blood that has passed through the filtration and defoaming part to the blood storage part through the lower side wall of the housing, and a partition is further provided around the venous blood flow inlet. By communicating the inside with the air flow path and forming a flow port at the bottom thereof, and providing the venous blood flow inlet with an inflow port whose upper end protrudes at a higher position than the flow port, venous blood can flow. This blood storage tank is characterized in that it is configured such that filtered and defoamed intracardiac blood flows from an inflow port through a flow port, and is led out from a blood outflow port.

[Function] In the blood storage tank of the present invention, intracardiac blood is supplied to the inside of the filtration/defoaming section from the inlet provided at the top, and foreign particles are removed while passing through the filtration/defoaming section and reaching the outside. At the same time, the foam is defoamed. The blood is then guided by the guiding part and passes along the lower side wall of the housing and enters the blood storage part. On the other hand, venous blood is guided directly to the blood storage section from the lower part of the blood storage tank. Then, the air bubbles mixed in the venous blood are discharged from the air vent port through the air flow path provided inside the filtration and defoaming section. The blood in the blood storage section is then led out from the blood outflow port.

[Example] Hereinafter, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is a longitudinal cross-sectional view of an embodiment of the blood reservoir of the present invention, and FIG. 2 is a cross-sectional view taken along the line - in FIG. 1. The blood storage tank is composed of a lower filtration/defoaming section 1 and a lower blood storage section 2, and is entirely housed within a housing 4. The housing is preferably made of transparent hard resin so that the amount of blood stored can be checked from the outside. An intracardiac blood flow inlet 5 is provided in the upper part of the housing, and a venous blood flow inlet 19 and a blood outlet 21 are provided in the lower part.

The filtration/defoaming unit 2 housed and fixed in the upper part of the housing has a structure in which a cylindrical first defoaming member 10, a second defoaming member 11, and a filtration member 9 are laminated. The intracardiac blood that has entered the chamber is introduced into the filtration and defoaming section through the cylindrical body 8. Cylindrical body 8
is for smoothly introducing blood into the filtration and defoaming section, and it is preferable that the upper part be formed with a smooth curve. Defoaming members 10 and 11 are made of open-cell foams such as polyurethane coated with a defoaming agent, and member 11 has a smaller pore diameter than 10. Although intracardiac blood contains a large amount of air bubbles, the bubbles are defoamed by passing through the defoaming member, and the separated air is discharged from the first air vent port 7. The filtration member 9 provided on the outside of the defoaming member is for removing microscopic tissue fragments and microaggregates contained in blood, and is made of polyester, nylon, or polypropylene and has a pore size of 20 to 50μ. Screen filters are preferred. Further, the filtration member also has a function of blocking minute air bubbles that have passed through the defoaming member, and coating with an antifoaming agent makes it possible to defoam the microbubbles, which is preferable. As is clear from FIG. 2, in the embodiment, the filter member 9 is pleated. In this embodiment, the filtration member is provided outside the defoaming member, but it may be provided inside the defoaming member. In addition to the screen filter, a depth filter can also be used as the filtration member, and it may not be pleated. Furthermore, the filter may have a single layer or multiple layers, and supporting members may be laminated.

The intracardiac blood that has passed through the filtration and defoaming section is guided by the guide section 3 provided at the lower part of the filtration and defoaming section to the blood storage section 2.
leading to. The guiding part 3 is a part of the side (left side in the figure)
It consists of a cylindrical blood collection part 14 with a chipped part and a flow part 15. The blood collection part 14 is provided so as to surround the outer periphery of the filtration and defoaming lower part, and its bottom part is inclined toward the flow part 15. That is, all the blood that has passed through the filtration and defoaming section flows toward the flow section 15, flows down from the flow section 15 into the constriction section 16 of the housing, and flows into the blood storage section along the side wall. The constriction part 16 is provided to prevent blood flowing down from the flow part 15 from dripping as much as possible, thereby preventing blood from re-foaming. In order to smooth the flow of blood, the flow section 15 and the constriction section 16 are preferably formed with smooth curves, and the side surface of the housing below the wedge section is preferably sloped.

Venous blood flows into the blood storage section 2 from the venous blood flow inlet 19, but air bubbles may also flow into the venous blood, and the blood storage section also needs a function to remove air bubbles. In order to achieve more complete separation of air bubbles, it is preferable to provide the venous blood inlet vertically at the bottom of the housing, with the venous blood inlet port 18 protruding inward. Preferably, the blood outflow port 21 is provided at the lowest part of the housing, and the venous blood flow inlet is provided above this. In the illustrated embodiment, a partition wall 17 is further provided around the protruding port to improve bubble separation efficiency. That is, inlet 1
Air bubbles flowing in from 9 with venous blood rise due to buoyancy, but the upper end of the inflow port 18 is
By providing it at a position higher than 0, air bubbles will not come out of the flow port along with the blood, and air bubbles will be completely removed. The removed air bubbles are
The air passes through an air flow path 12 provided inside the filtration and defoaming section and is discharged from the second air vent 6. The air flow path 12 is vertically provided substantially in the center of the filtration and defoaming section, and is separated from the defoaming section by a partition wall 13. The partition wall 13 not only ensures an air flow path, but also has the role of allowing intracardiac blood introduced through the partition wall 5 to flow smoothly along its outer surface.

The venous blood that has passed through the flow port 20 at the bottom of the partition wall 17 flows around the partition wall together with the intracardiac blood that has flowed down through the guide portion, and is led out from the blood outflow port 21.

In the blood reservoir of the present invention, since some members are configured to have multiple functions, the structure is simple, and as a result, manufacturing is easy and economically advantageous. That is, the partition wall 13 has the role of forming an air flow path therein, causing intracardiac blood to flow down the outer surface, and preliminarily separating air bubbles. Further, the partition wall 17 has the role of removing air bubbles from venous blood and holding the filtration and defoaming section and the guide section. Furthermore, by guiding the blood flow down by the constriction 16 provided in the housing, a dedicated member for guiding the blood flow down can be omitted.

[Effect of the invention] In the present invention, the accumulation of intracardiac blood and venous blood is
Since this is performed using two blood reservoirs, the priming volume of the artificial heart-lung circuit can be reduced. In addition, it is capable of efficiently defoaming and filtering intracardiac blood and removing bubbles from venous blood, and is functionally excellent as a blood storage tank. Furthermore, since the structure is simple and the number of constituent members is small, it is easy to manufacture and economically advantageous.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a preferred embodiment of the blood reservoir of the present invention, and FIG. 2 is a cross-sectional view. DESCRIPTION OF SYMBOLS 1... Filtration defoaming part, 2... Blood storage part, 3... Guide part, 4... Housing, 5... Intracardiac blood flow inlet, 6
... Air vent port, 12 ... Air flow path, 19 ... Venous blood flow inlet, 21 ... Blood outflow port.

Claims (1)

[Claims] 1 In a hollow body housing 4, an intracardiac blood flow inlet 5 is provided in the upper part, and a venous blood flow inlet 19 and a blood outlet 21 are provided in the lower part so that the venous blood flow inlet is above the blood outlet; A cylindrical filtration defoaming part 1 and a blood storage part 2 are provided separately at the lower part, and the air flow is communicated with the blood storage part 2 and the air vent 6 provided above the housing, and is separated from the filtration defoaming part 1. A passage 12 is provided vertically approximately in the center of the filtration and defoaming section,
A guide part 3 is provided to guide the blood that has passed through the filtration and defoaming part 1 to the blood storage part through the lower side wall of the housing, and a partition wall 1 is further provided around the venous blood flow inlet 19.
7 is provided to communicate the inside of the partition wall with the air flow path 12, and a flow port 20 is formed at the bottom thereof, and the venous blood flow inlet is provided with an inflow port 18 whose upper end projects to a higher position than the flow port 20. By providing a blood storage tank, venous blood is configured to flow from an inflow port through a flow port, merge with filtered and defoamed intracardiac blood, and be led out from a blood outflow port 21.