JPH0223310Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a medical heat exchanger.
Specifically, the present invention relates to a medical heat exchanger used for maintaining blood discharged outside the body at a desired temperature during extracorporeal circulation.

BACKGROUND OF THE INVENTION Extracorporeal circulation is commonly used as an adjunct to cardiac surgery, particularly open heart surgery. In extracorporeal circulation, which is used as an auxiliary method for open heart surgery, blood is removed from the body and sent to an oxygenator, where it is oxygenated and returned to the body. In aortic aneurysm surgery, extremely hypothermic extracorporeal circulation or moderate temperature extracorporeal circulation was used to cool the blood that was led outside the body. In this way, in extracorporeal circulation, it is necessary to maintain the blood discharged outside the body at a constant temperature, or to cool or heat it, and for this purpose, heat exchangers have traditionally been installed in the extracorporeal circulation circuit. It is being

Various types of heat exchangers 101 have been developed for use in extracorporeal circulation circuits.
For example, as shown in FIGS. 6 and 7, the first fluid circulation space 102 has a large number of heat exchangers, each having an internal space 103 that is liquid-tightly partitioned from the first fluid circulation space 102 and becomes a second fluid circulation space. The multi-tubular heat exchanger in which the exchange tubes 104 are arranged along the longitudinal direction of the first fluid circulation space 102 has high heat exchange efficiency and can be designed to be very compact, so it is suitable for medical heat. It is promising as an exchanger. Note that when the first fluid circulation space 102 is cylindrical, the first fluid is led out from the first fluid introduction pipe 105 that introduces the first fluid into the first fluid circulation space 102 and the first fluid circulation space 102. First fluid outlet pipe 1
06, as shown in FIGS. 6 and 7, are extended from the outside and communicated with the first fluid circulation space 102 approximately along a straight line passing through the center of the cross section perpendicular to the axis of the first fluid circulation space 102. It is considered a thing.

When performing heat exchange between blood and a heat exchange medium using such a multi-tubular heat exchanger 101, the heat exchange medium is passed through the first fluid circulation space 102, and the second fluid circulation space, that is, When blood flows through the internal space 103 of the heat exchange tube 104, the blood is distributed almost evenly to the heat exchange medium in order to maintain a relatively constant contact time. However, when the pressure loss during blood introduction is high and the extracorporeal circulation takes a long time, the heat exchange tube 104
Blood coagulation occurs in the internal space 103 of the heat exchange tube 103, and there is a high possibility that the heat exchange tube 103 will be blocked or constricted. On the contrary, the first
When blood flows through the fluid circulation space 102 and a heat exchange medium flows through the second fluid circulation space, that is, the internal space 103 of the heat exchange tube body 104, as described above, the problem of blockage or narrowing of the blood flow path occurs. However, as described above, the first fluid introduction pipe 105 and the first fluid introduction pipe 106 are connected to the axis of the first fluid circulation space 102. Since it has a configuration in which it extends from the outside and communicates with the first fluid circulation space 102 almost along a straight line passing through the center of the right-angled cross section, blood mainly flows toward the center of the first fluid circulation space 102, and the first fluid circulation The blood flow within the space 102 is not uniform and differs locally, and therefore, in areas where the blood flow is relatively high, blood flow between the heat exchange tube 104 through which the heat exchange medium flows in the internal space 103 is reduced. The contact may not be sufficient, resulting in insufficient heat exchange, and on the other hand, in areas where the blood flow is relatively low, the contact of blood with the heat exchange tube 104 may be more than necessary, resulting in excessive heat exchange. becomes. Further, as shown in FIGS. 6 and 7, the heat exchange tube 104 is connected to the blood circulation space 10.
2, the blood introduced from the blood introduction tube 105 flows through the blood circulation space 102.
When the blood flows into the blood circulation space 10, it immediately comes into contact with the heat exchange tube 104, and the blood flow enters the blood circulation space 10.
This is even more noticeable because the entirety of 2 is not given the opportunity to be equalized. In this way, if all the blood passing through the heat exchanger is not able to exchange heat evenly, the temperature distribution of the blood will vary, and heat exchange will be too much or too little for the blood, which will cause damage to blood components. It was difficult to say that this was a desirable option as it could have an adverse effect on the environment.

(Problems to be Solved by the Invention) Therefore, it is an object of the present invention to provide an improved medical heat exchanger. Another object of the present invention is to provide a medical heat exchanger capable of maintaining blood discharged outside the body during extracorporeal circulation at a desired temperature. A further object of the present invention is to provide a medical heat exchanger that can uniformly exchange heat between blood and a heat exchange medium and causes little damage to the blood. A further object of the present invention is to provide a medical heat exchanger that has low pressure loss during blood introduction and is very compact. A further object of the present invention is to provide a medical heat exchanger that can be integrated with an oxygenator.

(Means for Solving the Problems) The above objectives are such that a large number of heat exchange tubes each having an internal space that is fluid-tightly partitioned from the blood circulation space are arranged in a cylindrical blood circulation space to absorb the blood. The blood flowing through the blood circulation space is arranged along the longitudinal direction of the heat exchange tube through the tube wall of the heat exchange tube, and the heat exchange medium flowing through the internal space of the heat exchange tube generates heat. In a medical heat exchanger that performs blood exchange, a blood introduction tube that introduces blood into the blood circulation space and a blood outlet tube that draws blood out of the blood circulation space are perpendicular to the longitudinal direction of the blood circulation space and The heat exchange tube body extends from the outside along a straight line that touches the circumferential surface of the blood circulation space and communicates with the blood circulation space. In the axial direction of the blood circulation space, refer to the area surrounded by an arc that is approximately parallel to the line connecting the two intersections of the two inner circumferential lines of the introduction tube and the circumferential circle of the blood circulation space, and has an equal or slightly longer chord. A line that connects the two intersections of the two inner peripheral lines of the blood drainage tube and the circumferential circle of the blood circulation space in a cross section perpendicular to the axis of the blood circulation space that includes the space area formed by extending to and the axis of the blood drainage tube. They are arranged at uniform intervals throughout the blood circulation space, except for the space formed by extending in the axial direction of the blood circulation space an arcuate area that is approximately parallel to the arc and has an equal or slightly longer chord. Consists of a medical heat exchanger with special characteristics.

The present invention also provides a cylindrical housing that is closed at both ends, and a plurality of heat exchange tubes arranged at a distance from each other along the longitudinal direction of the housing. The heat exchange tubes are held liquid-tightly on the side wall of the housing without blocking the openings of the respective heat exchange tubes by the provided partition walls, and the inside of the housing is divided into three spaces, and both of the partition walls and A blood introduction tube and a blood outlet tube are connected to a blood circulation space formed in the center of the housing by the housing side wall and the outer wall of the heat exchange tube, and a heat exchange tube is fluid-tightly partitioned from the blood circulation space. A medical heat exchanger is shown in which a heat exchange medium inflow pipe is connected to one of two heat exchange medium circulation spaces formed at the end portion of the housing that communicates with the internal space of the body, and a heat exchange medium outflow pipe is connected to the other side. It is something. The present invention also provides a medical heat exchanger in which a blood inlet tube communicates with the blood circulation space near one partition wall, and a blood outlet tube communicates with the blood circulation space near the other partition wall. be. The present invention further provides a medical heat exchanger characterized in that the blood inlet tube and the blood outlet tube are rotated approximately 180 degrees around the circumferential surface of the blood circulation space. The present invention also provides a medical heat exchanger in which the volume of the two spaces in the blood circulation space where no heat exchange tubes are disposed is less than 40% of the blood circulation space.

(Function) However, the medical heat exchanger 1 of the present invention has the first to
As shown in FIG. 3, in a cylindrical blood circulation space 2, a large number of heat exchange tubes 4 having an internal space 3 that is fluid-tightly partitioned from the blood circulation space 2 are connected to the blood circulation space 2. A heat exchange medium is arranged along the longitudinal direction and communicates the blood flowing through the blood circulation space 2 through the tube wall of the heat exchange tube 4 with the internal space 3 of the heat exchange tube 4. In a medical heat exchanger 1 that performs heat exchange, a blood introduction tube 5 that introduces blood into the blood circulation space 2 and a blood outlet tube 6 that draws blood out of the blood circulation space 2 are arranged in the longitudinal direction of the blood circulation space 2. The heat exchange tube body 4 extends from the outside along a straight line with respect to the circumferential surface of the blood circulation space 2 and communicates with the blood circulation space 2 . Almost parallel to the line segment d ₁ connecting the two intersections c 1 and c 2 of the two inner circumferential lines l ₁ and l ₂ of the blood introduction tube ₅ and the circumferential circle s of the blood circulation space at the end face perpendicular to the _axis of the circulation space. A cross section perpendicular to the axis of the blood circulation space that includes a space portion 2a formed by extending in the axial direction of the blood circulation space 2 a portion surrounded by an arc having an equal or slightly longer chord d ₂ and the axis of the blood outlet tube 6. In the blood outlet tube 6, 2
It has _a chord d ₄ that is approximately parallel to the line segment d ₃ that connects the two intersection points c ₃ and c 4 of the inner circumferential lines l 3 and l ₄ of the book and the circumferential circle s of the blood circulation space 2 and that is equal to or slightly longer than the line segment d ₃ . The most distinctive feature is that they are uniformly spaced apart over the entire blood circulation space 2 except for a space portion 2b formed by extending an arcuately enclosed portion in the axial direction of the blood circulation space.

In this way, the blood inlet tube 5 and the blood outlet tube 6 are extended from the outside perpendicular to the longitudinal direction of the blood circulation space 2 and almost directly in contact with the circumferential surface of the blood circulation space 2 to communicate with the blood circulation space 2. Then,
The blood introduced from the blood introduction tube 5 has a flow that tries to swirl around the blood circulation space 2 along the circumferential surface of the blood circulation space 2, and the communication opening of the blood introduction tube 5 to the blood circulation space 2 is larger. Furthermore, since there is a heat exchange tube or a space in front of the communication opening, the blood introduced from the blood introduction tube 5 flows almost uniformly throughout the blood circulation space. The blood flowing in the blood circulation space 2 is distributed in the center of the blood circulation space 2, that is, in the center of the blood circulation space 2,
A specific heat exchange tube body 4 located on a substantially straight line connecting the communication port of the blood introduction tube 5 and the communication port of the blood discharge tube 6
The heat exchange tube 4 disposed in the blood circulation space 2 is in equal contact with almost the entire heat exchange tube 4 without being in contact with only the blood circulation space 2, and similarly, the communication opening of the blood lead-out tube 6 with the blood circulation space 2. is larger, and since there is a space in front of the communication opening where no heat exchange tube 4 exists, blood flowing through any part of the blood circulation space 2 is almost equally led out from the blood outlet tube 6. The Rukoto. Therefore, uniform heat exchange can be performed without locally excessive or insufficient heat exchange within the blood circulation space 2. Furthermore, in the heat exchanger of the present invention, blood flows outside the heat exchange tube 4, and as described above, the communication opening of the blood introduction tube 5 to the blood circulation space 2 is larger. Furthermore, since there is a space in front of the communication opening where the heat exchange tube body 4 does not exist, blood flows into the blood circulation space 2.
The pressure loss when introduced into the blood is not large, and there is little damage to blood components.

(Examples) Hereinafter, the present invention will be explained in more detail based on Examples.

FIG. 1 is a partially sectional perspective view showing the structure of an embodiment of the medical heat exchanger of the present invention, FIG. 2 is an axis-perpendicular sectional view of the embodiment, and FIG. FIG. 3 is an example axial cross-sectional view.

In the medical heat exchanger of this embodiment, the first to
As shown in FIG. 3, a large number of heat exchange tubes 4 are housed in a cylindrical housing 9 with both ends closed and constituted by a housing body 7 and end plates 8a and 8b that close both open ends of the housing body 7. The partition walls 10a and 10b provided at both ends of the plurality of heat exchange tubes 4 are spaced apart from each other along the longitudinal direction of the heat exchange tubes 4, and the heat can be removed without blocking the openings of the respective heat exchange tubes 4. The replacement tube body 4 is held on the side wall of the housing 9 in a liquid-tight manner. At the same time, these partition walls 10a, 10b
The inside of the housing 9 is divided into three spaces, and the central part of the housing 9 surrounded by the partition walls 10a and 10b, the side wall of the housing 9, and the outer wall of the heat exchange tube 4 is connected to the blood circulation space 2, and One partition wall 10 is fluid-tightly partitioned from this blood circulation space 2.
The end portion of the housing surrounded by a or 10b and the end wall and side wall of the housing 9 becomes two heat exchange medium circulation spaces 11a and 11b. Both of these two heat exchange medium circulation spaces 11a and 11b communicate with the internal space 3 of the heat exchange tube body 4, which is separated from the blood circulation space 2 in a fluid-tight manner. A blood inlet pipe 5 and a blood outlet pipe 6 are connected to the blood circulation space 2 formed in this way, and a heat exchange medium outflow pipe 12 is connected to one heat exchange medium circulation space 11a, and a heat exchange medium outflow pipe 12 is connected to the other heat exchange medium circulation space 11a. Heat exchange medium inflow pipes 13 are communicated with each of the circulation spaces 11b.

In the medical heat exchanger 1 of this embodiment, the blood inlet tube 5 and the blood outlet tube 6 are perpendicular to the longitudinal direction of the housing 9 and
Blood circulation space 2 extends from the outside approximately along a straight line that touches the circumferential surface of the blood circulation space 2, that is, extends from the outside approximately along a straight line that is perpendicular to the longitudinal direction of the blood circulation space 2 and touches the circumference of the blood circulation space 2. It is communicated with the circulation space 2. Note that the blood inlet tube 5 and the blood outlet tube 6 do not need to extend from the outside strictly along a straight line perpendicular to the longitudinal direction of the blood circulation space 2 and in contact with the circumferential surface of the blood circulation space 2.
The blood flowing through the blood circulation space 2
It may deviate from the straight line to some extent as long as it can effectively provide a flow along the circumferential surface of the straight line. Moreover, the blood introduction tube 5 and the blood outlet tube 6 are those that, at least in a portion immediately before communicating with the blood circulation space 2, are substantially along a straight line that is perpendicular to the longitudinal direction of the blood circulation space 2 and that is in contact with the circumferential surface of the blood circulation space 2. The directionality of the region behind it is arbitrary. Furthermore, the positions of these blood introduction tubes 5 and blood outlet tubes 6 are not particularly limited, but they can be used as a heat exchange medium flowing through the internal space of the heat exchange tube 4 inserted into the blood circulation space 2. In order to perform effective heat exchange with the blood flowing in the blood circulation space 2, it is necessary to communicate with the blood circulation space 2 from positions separated from each other, and preferably, as shown in FIGS. As shown, the blood introduction tube 5 is connected to one partition wall 10a or 10b.
It is desirable that the blood outlet tube 6 communicates with the blood circulation space 2 from the vicinity of the other partition wall 10b or 10a, and further, as shown in FIGS. 1 and 2. As such, it is desirable that the blood introduction tube 5 and the blood outlet tube 6 be in a positional relationship rotated by approximately 180 degrees on the circumferential surface of the blood circulation space 2.

In addition, in the medical heat exchanger 1 of the present invention, the heat exchange tube body 4 arranged along the longitudinal direction of the blood circulation space 2 is arranged in the blood circulation space including the axis of the blood introduction tube 5 as shown in FIG. In a cross section perpendicular to the spatial axis, it is approximately parallel to a line segment d ₁ connecting the two intersections c ₁ and c ₂ of the two inner circumferential lines l ₁ and l ₂ of the blood introduction tube 5 and the circumferential circle s of the blood circulation space. A space part 2a formed by extending a part surrounded by an arc having an equal or slightly longer chord _d2 in the axial direction of the blood circulation space 2, and a cross section perpendicular to the axis of the blood circulation space that also includes the axis of the blood outlet tube 6. , substantially parallel to and equal to or equal to the line segment d 3 connecting the two intersections c ₃ and c ₄ of the two inner circumferential lines l ₃ and l ₄ of the blood outlet tube 6 and the circumferential circle s of the blood circulation space ₂ . A space region 2 formed by extending a region surrounded by an arc having a slightly long chord d ₄ in the axial direction of the blood circulation space 2
They are uniformly spaced apart throughout the blood circulation space 2 except for b. That is, in the blood circulation space 2, in front of the communication openings of the blood introduction tube 5 and the blood outlet tube 6, space parts 2a and 2b where no heat exchange tube 4 is present are provided over the entire length of the blood circulation space 2. . Therefore, from the blood introduction pipe 5 to the blood circulation space 2
The blood that has flowed into the space spreads evenly in the circumferential direction and longitudinal direction of the blood circulation space 2 in the space portion 2a, and when passing through the portion 2c of the blood circulation space 2 where the heat exchange tube 4 is present, the blood flows for heat exchange. A portion 2c that is in contact with the group of tubes 4 and further has a heat exchange tube 4
Since the blood that has passed through flows through the space 2b until it reaches the blood outlet tube 6, the blood that has passed through both the circumferential direction and the longitudinal direction of the blood circulation space 2 comes into almost equal contact with the heat exchange tube 4. The blood is drawn out from the blood drawing tube 6. In this way, the space parts 2a and 2b where the heat exchange tube 2 does not exist serve as a kind of blood flow adjustment chamber that approximately equalizes the flow rate of blood passing through the heat exchange tube 4 provided in the blood circulation space 2. act.

In addition, in this way, the space part 2a that acts as a blood flow adjustment chamber is connected to the two inner peripheral lines l ₁ and l ₂ of the blood introduction tube 5 and the blood circulation space in a cross section perpendicular to the axis of the blood circulation space that includes the axis of the blood introduction tube 5. A part surrounded by an arc having a chord d 2 that is approximately parallel to the line segment d ₁ connecting the two intersections c ₁ and c ₂ with the circumferential circle s and has an equal or slightly longer chord d ₂ is extended in the axial direction of the blood circulation space 2 Similarly, the space portion 2c is formed in a cross section perpendicular to the axis of the blood circulation space including the axis of the blood outlet tube 6, and the two inner peripheral lines l ₃ and c ₄ of the blood outlet tube 6 and the blood circulation space. A line segment connecting the two intersections c ₃ and c ₄ with the circumferential circle s of 2
The shape is formed by extending in the axial direction of the blood circulation space 2 a region surrounded by an arc having a chord d ₄ that is approximately parallel to d ₃ and is equal to or slightly longer than each of the space regions 2 a and 2 b. is too inclined with respect to the communication opening of the blood inlet tube 5 or the blood outlet tube 6 to the blood circulation space 2, that is, it is surrounded by an arcuate shape having a chord whose inclination is significantly different from that of the line segment _d1 or _d3 . If the shape is extended in the axial direction of the blood circulation space 2, the space 2c where the heat exchange tube 4 is arranged will not only become narrower than necessary, but also the blood flow will be unevenly distributed. This is _undesirable as it may lead to
Or, if d ₄ is too larger than the line segment d ₁ or d ₃ (corresponding to the inner diameter of the communication opening to the blood circulation space 2 of the blood inlet tube 5 or blood outlet tube 6), the arrangement of the heat exchange tube spatial part 2c
This is because it is undesirable because it makes it unnecessarily narrow. However, spatial site 2
The arcuate chords d ₂ and d ₄ that are the cross-sectional shapes of a and 2b do not need to be strictly parallel to the line segments d ₁ and d ₃ , and are not necessarily parallel to the blood circulation space 2 of the blood introduction tube 5 or the blood outlet tube 6. The inclination may be different to some extent as long as the blood flow can be distributed almost evenly in the circumferential direction of the blood circulation space 2 at the front surface of the communication opening. In addition, the lengths of the strings d ₂ and d ₄ are the effective spatial parts 2a and 2b.
The length must be at least the same as the line segments d ₁ and d ₃ to form a line segment d ₁ and d 3 , but it is difficult to specify an upper limit because it also depends on the slope of the chords d 2 and d ₄ . It is desirable that the length of the arc having d ₂ and d ₄ be 2/3 or less of the length of the circumference of the blood circulation space 2 . Furthermore, such a heat exchange pipe body 4
Although the number of heat exchange tubes 4 arranged in the blood circulation space 2 is naturally reduced by providing the space parts 2a and 2b in which no space exists in the blood circulation space 2, the number of heat exchange tubes 4 arranged in the blood circulation space 2 is naturally reduced. If such a shape is used, there will be virtually no reduction in heat exchange efficiency due to a reduction in the number of heat exchange tubes, and furthermore, the two space portions 2a and 2b where the heat exchange tubes 4 are not arranged.
When the volume is less than 10% of the blood circulation space 2, there is almost no decrease in heat exchange efficiency.

Actually, the cylindrical blood circulation space 2 with a radius of 55.6 mm and a length of 80 mm is connected to the blood inlet tube 5 and the blood outlet tube 6 with an inner diameter of 12 mm arranged as described above, and the The blood circulation space 2 has a shape as shown in FIG.
Heat exchange tube 4 with an overall inner diameter of 2.14 mm and an outer diameter of 2.38 mm
A heat exchanger consisting of 223 pieces evenly spaced,
A heat exchanger having the same configuration except that the space parts 2a and 2b were not provided and heat exchange tubes 4 were arranged in these parts as well as in other parts (the number of heat exchange tubes was 253). When we examined the heat exchange efficiency η by pumping blood at a blood flow rate of 4/min, there was no difference in performance with η = 0.4 in both cases, and the pressure loss was 1 mmH 2 O in the former heat exchanger and 1 mmH ₂ O in the latter heat exchanger. 5 in vessels
mmH ₂ O, and the superiority of providing the space portions 2a and 2b in which the heat exchange tube 4 is not disposed was demonstrated.

The medical heat exchanger 1 of the present invention having such a configuration is suitably incorporated and used in various extracorporeal circulation circuits. As shown in FIG. 5, it is preferably used as an artificial lung device that is integrated with an artificial lung and a blood reservoir.

In the embodiment shown in FIGS. 4 and 5, the oxygenator 21 includes a cylindrical housing body 22 and mounting covers 23a and 23 that close both open ends of the housing body 22.
A plurality of hollow fiber membranes 24 are arranged in parallel and spaced apart from each other along the longitudinal direction of the housing, extending throughout the housing. Both ends of the hollow fiber membrane 24 are fluid-tightly held in the housing body 22 by partition walls 25a and 25b, with the respective openings not being closed. Also, one mounting cover 2
A gas inflow port 27 is provided in a gas inflow space 26 that communicates with the internal space of the hollow fiber membrane formed by the housing body 3a, the housing body 22, and the partition wall 25a;
Gas flow ports 29 are provided in communication with the gas flow spaces 28 that communicate with the inner space of the hollow fiber membrane formed by the above. Further, a blood inflow pipe 31 and a blood outflow pipe 32 are provided in communication with the blood chamber 30, which is constituted by the inner wall of the housing body 22, the partition walls 25a and 25b, and the outer wall of the hollow fiber membrane 24.

The oxygenator 21 shown in this embodiment is of a type that performs gas exchange by blowing oxygen-containing gas such as air into the internal space of the hollow fiber membrane 24 and causing blood to flow outside the hollow fiber membrane 14. Other hollow fiber membranes are also used, such as those that perform gas exchange by flowing blood into the internal space and flowing oxygen-containing gas outside the hollow fiber membrane, or those that have a flat membrane type gas exchange membrane. It will be done. Among such oxygenators, it is preferable to use a type that allows blood to flow outside the hollow fiber membrane as shown in this embodiment, and if this type of oxygenator is used, there is less pressure loss, so blood can flow through the circulation circuit. There is no need to provide a blood pump in front of the oxygenator, and blood can be sent to the oxygenator and further to the blood reservoir by removing blood only by the drop from the human body.

As shown in FIG. 5, the blood inlet tube 31 of the artificial lung 21 is fluid-tightly connected to the blood outlet tube 6 of the medical heat exchanger 1 via a connecting tube 33. The liquid-tight connection between the connecting tube 33 and the blood inflow tube 31 of the oxygenator 21 and the blood outlet tube 6 of the medical heat exchanger 1 can be achieved by, for example, threaded fitting, tapered fitting, or fitting via an O-ring. liquid-tight fit such as
This is done by liquid-tight bonding such as ultrasonic or high-frequency bonding or bonding through adhesive, but of course the blood inflow tube 31 of the oxygenator 21 and the blood outlet tube of the medical heat exchanger 1 are connected by similar connection means. 6 may be directly liquid-tightly connected. Although the medical heat exchanger 1 of this embodiment is slightly different from the medical heat exchanger 1 of the embodiment shown in FIGS. 1 to 3 in the arrangement positions of the blood inlet tube 5 and the blood outlet tube, They are essentially the same. Furthermore, in addition to the blood inlet port 34 connected to the extracorporeal circulation circuit, the blood introduction tube 5 of the medical heat exchanger 1 of this embodiment has a card for introducing blood bled during surgery into the extracorporeal circulation circuit. An ionotomy inlet port 35 is provided, and the blood introduction tube 5 is further provided with a probe insertion port 36 for temperature measurement. Furthermore, flexible extension pipes 38 each having a water inlet port (not shown) or a water outlet port 37 at the tip are connected to the heat exchange medium inflow pipe 13 and the heat exchange medium outflow pipe 12. .

On the other hand, a blood inlet 42 of a blood reservoir 41 is fluid-tightly connected to a blood outflow pipe 32 of the artificial lung 21 via a connecting pipe 39. Connecting pipe 39, blood outflow pipe 32 of artificial lung 21, and blood inlet 42 of blood storage tank 41
The liquid-tight connection between the connecting tube 33 and the blood inlet tube 31 of the artificial lung 21 and the blood outlet tube 6 of the medical heat exchanger 1 is made in the same manner as in the case of the liquid-tight connection between the connecting tube 33 and the blood inlet tube 31 of the artificial lung 21 and the blood outlet tube 6 of the medical heat exchanger 1. This blood reservoir 41 connected to the oxygenator 21 is
A blood inlet 42 , a blood inlet 43 that communicates with the blood inlet 42 and has a bottom with almost no height difference from the blood inlet 42 , and a bottom that communicates with the blood inlet 43 and gradually descends from the blood inlet 43 . Blood storage part 4
4 and a defoaming member 47 that traverses the entire width of the blood flow path of the blood inflow portion 43 is provided in a housing 46 formed of a hard member having a blood outlet 45 provided at the lower part of the blood storage portion 44. That's what happens. In addition to the blood outlet port 45 connected to the extracorporeal circulation circuit, this blood storage tank 41 also has a cardioplegia port 48 connected to a circuit for sending blood to the cardiac veins, which communicates with the lower part of the blood storage section 44. Furthermore, a temperature measurement probe insertion port 49 for measuring the temperature of blood in the blood storage tank 41 is provided.
Also provided.

In this way, the medical heat exchanger 1 and the blood storage tank 41
In an artificial lung device that is integrated with an artificial lung 21,
Blood removed from the human body first flows into the medical heat exchanger 1 through the blood introduction tube 5. As described above, the blood inlet tube 5 and the blood outlet tube 6 are extended from the outside along a straight line perpendicular to the longitudinal direction of the blood circulation space 2 and in contact with the circumferential surface of the blood circulation space 2 to enter the blood circulation space 2. Because of the communication, the blood introduced into the blood circulation space 2 from the blood introduction tube 5 has a flow that tries to swirl around the blood circulation space 2 along the circumferential surface of the blood circulation space 2, and as described above, the blood is introduced into the blood circulation space 2. Since space portions 2a and 2b where no heat exchange tube body 4 exists are provided in front of the communication openings of the inlet tube 5 and the blood outlet tube 6 to the blood circulation space 2, it is difficult to understand the inside of the blood circulation space 2. The circulating blood is distributed only to a specific group of 4 heat exchange tubes located in the center of the blood circulation space 2, that is, on a substantially straight line connecting the communication port of the blood introduction tube 5 and the communication port of the blood discharge tube 6. The heat exchange tube body 4 disposed in the blood circulation space 2 is almost entirely in contact with the heat exchange tube body 4 evenly, without being primarily in contact with the heat exchange tube body 4 . Therefore, the heat exchange medium inlet pipe 13
Water, which is a heat exchange medium, flows into the heat exchange medium circulation space 11a, passes through the internal space 3 of the heat exchange pipe body 4 communicating with it, reaches the heat exchange medium circulation space 11b, and flows out from the heat exchange medium outflow pipe 12. , heat exchange through the tube wall of the heat exchange tube body 4 in the blood circulation space 2 is performed efficiently and uniformly, and the blood heated or cooled to a desired temperature is heat exchanged through the blood outlet tube 6. The blood is led out of the vessel 1 and sent to the oxygenator 21 through the blood inflow tube 31 of the oxygenator 21, which is in fluid-tight communication with the blood outlet tube 6. The blood flowing in from the blood inflow pipe 31 of the artificial lung 21 exchanges gas with the oxygen-containing gas flowing inside the hollow fiber membrane 24 via the hollow fiber membrane 24 while passing through the blood chamber 30.
Excess carbon dioxide in the blood is removed and consumed oxygen is added. The oxygenated blood flows out from the blood outflow pipe 32 of the artificial lung 21 and flows into the blood storage tank 41 through the blood inlet port 42 of the blood storage tank 41 that communicates with the oxygenated blood. The blood that flows from the blood inlet port 42 to the blood inflow part 43 communicating with the blood inflow part 43 and reaches the defoaming member 47 provided in the middle of the blood inflow part 43 passes through the defoaming member 47.
While passing through the blood, air bubbles contained in the blood come into contact with the cells of the foam of the defoaming member 47, and a plurality of air bubbles coalesce and grow, moving from the blood to the upper space inside the blood reservoir 41. The blood is degassed and moved to the blood storage section 44 which is in communication with the blood storage section 4 temporarily.
After being stored in the blood storage section 44, the blood is drawn out from a blood outlet 45 provided at the lower part of the blood storage section 44 and sent to the human body.

(Effects of the invention) As described above, the medical heat exchanger of the present invention has
In a cylindrical blood circulation space, a large number of heat exchange tubes each having an internal space that is fluid-tightly partitioned from the blood circulation space are arranged along the longitudinal direction of the blood circulation space. In a medical heat exchanger that performs heat exchange between blood flowing through a blood circulation space through a tube wall of an exchange tube and a heat exchange medium flowing through an internal space of a heat exchange tube, A blood introduction tube that introduces blood into the blood circulation space and a blood outlet tube that draws blood out of the blood circulation space are connected from the outside approximately along a straight line that is perpendicular to the longitudinal direction of the blood circulation space and that is in contact with the circumferential surface of the blood circulation space. The heat exchange tube body is extended and communicated with the blood circulation space, and the heat exchange tube body is connected to the two inner peripheral lines of the blood introduction tube and the circumference of the blood circulation space in a cross section perpendicular to the axis of the blood circulation space that includes the axis of the blood introduction tube. A space region formed by extending in the axial direction of the blood circulation space a region surrounded by an arc having an equal or slightly longer chord and approximately parallel to the line segment connecting the two intersections with the surface circle, and a blood outlet tube. An arcuate shape that is approximately parallel to the line segment connecting the two intersections of the two inner circumferential lines of the blood outlet tube and the circumferential circle of the blood circulation space in a cross section perpendicular to the axis of the blood circulation space including the axis, and has an equal or slightly longer chord. The blood circulation space is characterized by being uniformly spaced apart throughout the blood circulation space except for the space formed by extending the area surrounded by the blood circulation space in the axial direction of the blood circulation space.
The blood flowing through the blood circulation space can be evenly distributed within the blood circulation space, and as a result, all the blood passing through the heat exchanger can undergo equal heat exchange, and the temperature of the blood can be evenly distributed. It exhibits stable performance without adversely affecting blood components due to uneven distribution and excessive or insufficient heat exchange with the blood, and has low pressure loss during blood circulation. be.

Furthermore, the medical heat exchanger of the present invention has a plurality of heat exchange tubes spaced apart from each other along the longitudinal direction of the housing in a cylindrical housing with both ends closed. Partition walls provided at both ends of the tubes hold the heat exchange tubes liquid-tightly against the housing side wall without blocking the openings of the respective heat exchange tubes, and divide the inside of the housing into three spaces. The blood introduction tube and the blood outlet tube are respectively communicated with the blood circulation space formed at the center of the housing by these partition walls, the housing side wall, and the heat exchange tube outer wall, and are fluid-tightly partitioned from the blood circulation space. A heat exchange medium inflow pipe is connected to one of two heat exchange medium circulation spaces formed at the end portion of the housing that communicate with the internal space of the heat exchange pipe body, and a heat exchange medium outflow pipe is connected to the other. If there is one, it can have a compact capacity and high performance, so it can be preferably used by being integrated with an oxygenator, for example, and the blood introduction tube can be connected to the blood circulation space from the vicinity of one partition wall. In addition, the blood outlet tube communicates with the blood circulation space from near the other partition wall, and the blood introduction tube and the blood outlet tube are rotated approximately 180 degrees on the circumferential surface of the blood circulation space. Furthermore, if the volume of the two spaces in the blood circulation space where the heat exchange tubes are not arranged is less than 40% of the blood circulation space, more efficient heat exchange can be performed.

[Brief explanation of the drawing]

Fig. 1 is a partially sectional perspective view showing the structure of an embodiment of the medical heat exchanger of the present invention, Fig. 2 is an axis-perpendicular sectional view of the same embodiment, and Fig. 3 is an axial cross-section of the same embodiment. Figure 4 is a partially sectional front view of an artificial lung device incorporating another embodiment of the medical heat exchanger of the present invention, and Figure 5 is
The figure is a perspective view of a medical heat exchanger and an oxygenator in the same oxygenator, FIG. 6 is an axis-perpendicular cross-sectional view showing the structure of the conventional heat exchanger, and FIG. 7 is an axial direction view of the conventional example. FIG. 1...Medical heat exchanger, 2...Blood circulation space,
2a, 2b... Spatial portion where no heat exchange tube exists, 2c... Spatial portion where a heat exchange tube exists,
3... Internal space, 4... Heat exchange tube, 5... Blood introduction tube, 6... Blood outlet tube, 7... Housing main body, 8a, 8b... End plate, 9... Housing,
10a, 10b... partition wall, 11a, 11b... heat exchange medium circulation space, 12... heat exchange medium outflow pipe,
13... Heat exchange medium inflow pipe, 21... Artificial lung, 4
1...Blood reservoir.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A large number of heat exchange tubes each having an internal space that is fluid-tightly partitioned from the blood circulation space in a cylindrical blood circulation space along the longitudinal axis of the blood circulation space. A medical device that performs heat exchange between blood flowing through a blood circulation space through the tube wall of the heat exchange tube and a heat exchange medium flowing through the internal space of the heat exchange tube. In the blood circulation space heat exchanger, a blood introduction tube that introduces blood into the blood circulation space and a blood outlet tube that draws blood out of the blood circulation space are perpendicular to the longitudinal direction of the blood circulation space and arranged around the circumference of the blood circulation space. The heat exchange tube body is extended from the outside along a straight line that touches the surface and communicated with the blood circulation space, and the heat exchange tube body is connected to two parts of the blood introduction tube in a cross section perpendicular to the axis of the blood circulation space that includes the axis of the blood introduction tube. A part surrounded by an arc that is approximately parallel to the line connecting the two intersection points of the inner circumferential line of the book and the circumferential circle of the blood circulation space and has an equal or slightly longer chord is extended in the axial direction of the blood circulation space. In a cross section perpendicular to the axis of the blood circulation space that includes the space formed by the space and the axis of the blood circulation tube, approximately the line segment connecting the two intersections of the two inner peripheral lines of the blood circulation tube and the circumferential circle of the blood circulation space. It is characterized by being uniformly spaced apart throughout the blood circulation space except for the space formed by extending in the axial direction of the blood circulation space a part surrounded by an arcuate parallel and having an equal or slightly longer chord. medical heat exchanger. (2) Inside a cylindrical housing with both ends closed,
A plurality of heat exchange tubes are arranged at a distance from each other along the longitudinal direction of the housing, and the opening of each heat exchange tube is closed by partition walls provided at both ends of the plurality of heat exchange tubes. The heat exchange tube is held liquid-tightly on the side wall of the housing, and the inside of the housing is divided into three spaces, and the partition wall, the side wall of the housing, and the outer wall of the heat exchange tube are formed in the center of the housing. A blood inlet tube and a blood outlet tube are connected to the blood circulation space, respectively, and two heat exchangers are formed at the end portions of the housing that are fluid-tightly partitioned from the blood circulation space and communicate with the internal space of the heat exchange tube. The medical heat exchanger according to claim 1, wherein a heat exchange medium inflow pipe is connected to one side of the medium circulation space, and a heat exchange medium outflow pipe is connected to the other side of the medium circulation space. (3) According to the scope of claim 2 of the utility model registration, the blood inlet tube communicates with the blood circulation space from the vicinity of one partition wall, and the blood outlet tube communicates with the blood circulation space from the vicinity of the other partition wall. Medical heat exchanger as described. (4) Any of claims 1 to 3 of the utility model registration claim, characterized in that the blood introduction tube and the blood outlet tube are rotated approximately 180 degrees on the circumferential surface of the blood circulation space. A medical heat exchanger described in . (5) Two spaces in the blood circulation space where heat exchange tubes are not placed occupy 40% of the blood circulation space.
The first claim for utility model registration that has a volume of less than
The medical heat exchanger according to any one of Items to Item 4.