JPH084621B2 - Extracorporeal blood circulation device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an extracorporeal blood circulation device, and more specifically, it performs gas exchange of blood with an artificial lung, and then has a blood inlet opening horizontally on the bottom surface. More particularly, the present invention relates to an extracorporeal blood circulation device that is compact and configured to prevent air bubbles from being mixed into blood by being overflowed into a blood storage tank, temporarily stored therein, and then supplied to a human body.

BACKGROUND OF THE INVENTION For example, when performing a chest operation or the like, an extracorporeal blood circulation circuit is constructed using an artificial lung, and carbon dioxide and oxygen are exchanged by the artificial lung. In this case, the blood is adjusted to a predetermined temperature by a heat exchanger, and then gas exchange is performed in an oxygenator, and then the blood is temporarily stored in a blood reservoir to remove bubbles and feed a fixed amount of blood, and then pumped. Is delivered to the human body with a constant pulsation or pulsation rate.

Here, the blood storage tank includes a closed-type blood storage tank that stores blood in a bag-shaped soft member in an airtight state and an open-type blood storage tank that stores blood in a housing made of a hard member. In this case, since the open type blood reservoir is easy to check the priming and blood storage volume, and can be easily configured integrally with the artificial lung,
Various extracorporeal blood circulation devices using such an open type blood reservoir have been proposed.

Therefore, FIG. 1 shows a schematic configuration of an extracorporeal blood circulation device according to the prior art proposed by the applicant. This extracorporeal blood circulation device is configured by integrally forming an artificial lung 2 and a blood reservoir 4, and is connected to a human body via a pump (not shown) that causes pulsation or pulsation. Blood B discharged from the human body is introduced into a heat exchanger, adjusted to a predetermined temperature with hot water or cold water, and then introduced into artificial lung 2 through blood supply port 6. The artificial lung 2 contains a large number of hollow fiber membranes 10 through which the gas A containing oxygen supplied from the gas inflow port 8 flows.
The blood B passes around the hollow fiber membrane 10 so that the blood B
The carbon dioxide contained therein and the oxygen contained in the gas A are exchanged. Next, the blood B that has risen in the artificial lung 2 flows into the blood reservoir 4 by overflowing from the upper end portion thereof and is stored therein. The gas A for which gas exchange has been completed is discharged to the outside through the gas outflow port 12. Subsequently, the blood B defoamed by being stored in the blood storage tank 4 is supplied to the human body through the blood outflow port 14.

[Object of the Invention] The present invention has been made in view of the above-mentioned extracorporeal blood circulation device, and the blood that has undergone gas exchange in the artificial lung is opened horizontally from the blood inlet opening in the same plane as the bottom face. It is an object of the present invention to provide an extracorporeal blood circulation device having a compact structure capable of extremely effectively preventing air bubbles from being entrained and generated in blood by causing the air to overflow and be stored in the blood storage tank.

[Means for Achieving the Purpose] In order to achieve the above-mentioned object, the present invention provides an extracorporeal blood circulation device in which an artificial lung and a blood reservoir are integrally configured to allow blood to flow from the artificial lung into the blood reservoir. After gradually expanding the blood inlet for downward from the lower direction to the upper direction,
It is characterized in that the blood reservoir is opened horizontally in the same plane with respect to the bottom surface of the blood reservoir.

[Embodiment] Next, a preferred embodiment of the extracorporeal blood circulation device according to the present invention will be given and described in detail below with reference to the accompanying drawings.

2 and 3, reference numeral 30 indicates a main body of the extracorporeal blood circulation device, and the main body 30 integrally integrates the heat exchanger 32, the artificial lung 34, and the open type blood storage tank 36. It is configured in.

The heat exchanger 32 has a large number of heat exchange tubes 40 housed in a cylindrical housing 38, and the heat exchange tubes 40 are supplied with hot or cold water W from one water port 42. The water is discharged from the other water port 44. The blood B flowing into the heat exchanger 32 from the blood supply port 46 is heated or cooled to a predetermined temperature by passing around the heat exchange pipe 40, and then the two connecting pipes 48a and 48b are connected. It is supplied to the artificial lung 34 through the air (see FIG. 3).

The artificial lung 34 removes carbon dioxide from the blood B and adds oxygen, and contains a large number of hollow fiber membranes 52 in a bundle in a substantially cylindrical housing 50 with a narrowed central portion. Partition walls 54a and 54b for holding both ends of the hollow fiber membrane 52 are attached to both upper and lower ends of the housing 50. In this case, the hollow fiber membrane
A space surrounded by the housing 50 and the partition walls 54a and 54b in which 52 is housed is connected at its lower end side to the heat exchanger 32 via the connection conduits 48a and 48b, and the gas exchange chamber 56 in which the blood B flows. Make up. Lid members 58a and 58b are further attached to the upper and lower ends of the housing 50, and a gas supply chamber 60 and a gas exhaust chamber 62 are defined between the partition walls 54a and 54b and the lid members 58a and 58b. The hollow fiber membrane 52 is supplied with the gas A containing oxygen from the gas inflow port 64 via the gas supply chamber 60. Further, the gas A delivered from the hollow fiber membrane 52 is exhausted from the gas outflow port 66 via the gas exhaust chamber 62.

On the other hand, the upper end portion side of the gas exchange chamber 56 in the artificial lung 34 once extends horizontally, then extends vertically for a predetermined length in the vertically upward direction, and its end portion expands into two L-shapes. Connection pipeline
It communicates with the blood reservoir 36 via 68a and 68b. in this case,
The bottom surface of the blood storage tank 36 is composed of first to third step portions 70a to 70c, and the blood inlets 72a and 72b, which are the end portions of the connection conduits 68a and 68b, which are widened, are the uppermost layers. The meshes 74a and 74b for defoaming are provided on both sides of the first step portion 70a to open in the same plane as the first step portion 70a and in a horizontal state. Here, the blood reservoir 36 is composed of a transparent plastic body or the like, and above the blood inlets 72a and 72b, a drug mixture injection port 76a for injecting a vasodilator, an antithrombotic drug, etc. into the blood B. And 76b are provided.

A urethane defoaming material 78 is provided in the first step portion 70a of the blood storage tank 36 in the vicinity of the blood inlets 72a and 72b in order to remove bubbles of the blood B at the time of inflow. Further, in order to suppress the resonance vibration of the blood surface in the substantially central portion of the second step portion 70b where the blood B is stored, the blood storage area on the second step portion 70b is set to the first blood storage portion 80a and the second blood storage portion 80a. Separating wall 82 that is substantially separated from blood storing part 80b
Is provided. Further, a blood outflow port 84 for delivering the blood B stored in the blood storage tank 36 to the human body side is provided at the end side of the lowermost third step portion 70c. In this case, the blood outflow port 84 communicates with the human body via a pump (not shown) that causes pulsation or pulsation. The first to third step portions 70
The a to 70c are smoothly connected via the inclined surfaces 87a and 87b.

The extracorporeal blood circulation device according to the present invention is basically constructed as described above. Next, its operation and effect will be explained.

First, the blood B flowing in from the blood supply port 46 is supplied to the artificial lung 34 through the gap between the heat exchange tubes 40 housed in the heat exchanger 32. In this case, water W maintained at a predetermined temperature through the water ports 42 and 44 in the heat exchange pipe 40.
Is circulated, and the water B heats or cools the blood B to a predetermined temperature.

The blood B flowing from the heat exchanger 32 into the oxygenator 34 via the connecting conduits 48a and 48b is added with oxygen in the gas exchange chamber 56 surrounded by the housing 50, and carbon dioxide is removed. That is, a large number of bundled hollow fiber membranes 52 are accommodated in the housing 50, and the gas A containing oxygen is introduced into the hollow fiber membranes 52 from the gas inflow port 64 via the gas supply chamber 60. Has been sent. Therefore, blood B
Exchanges oxygen and carbon dioxide through the hollow fiber membrane 52. The gas A containing carbon dioxide is the gas exhaust chamber 62
Through the gas outflow port 66.

The oxygenated blood B in the artificial lung 34 is connected to the connecting conduit.
The blood flows into the blood reservoir 36 through the blood inlets 72a and 72b via the 68a and 68b. Here, the blood inlets 72a, 72b defined at the ends of the connecting conduits 68a, 68b are widened and open in the same plane with respect to the first step 70a in the blood reservoir 36. .
In this case, the blood B reaching the expanded blood inlets 72a and 72b has a large cross-sectional area, and thus the flow velocity is reduced. Further, since the blood inlets 72a and 72b are defined in the same plane as the first step portion 70a, the blood B flowing out from the blood inlets 72a and 72b is restrained from flowing into the blood reservoir 36. . Therefore, blood B is less likely to foam, and the mesh
After being rectified by 74a and 74b, it gently overflows into the blood reservoir 36. Next, the blood B is reliably removed of bubbles contained in the blood B by the urethane defoaming material 78, and is stored in the blood reservoir 36 through the smooth inclined surfaces 87a and 87b without being foamed.

The connecting conduits 68a and 68b are formed in an L-shape that extends once horizontally from the upper end of the gas exchange chamber 56 that constitutes the artificial lung 34 and then extends upward for a predetermined length. Has been done. Therefore, the blood B flowing out of the gas exchange chamber 56 rises in the L-shaped connecting conduits 68a and 68b based on the pressure generated by the drop perfusion from the pump or the human body (not shown), so that the flow velocity decreases due to its own weight. Provoke. As a result, the blood B flows into the blood reservoir 36 without being ejected, so that the mixing of air bubbles into the blood B is suppressed more suitably.
Further, since the blood inlets 72a, 72b are located higher than the gas exchange chamber 56 in the artificial lung 34, when the pump stops, air is introduced into the gas exchange chamber 56 from the blood inlets 72a, 72b. There is no inflow. Therefore, in the artificial lung 34,
It is possible to prevent the occurrence of inconveniences such as the surface of blood B coming into contact with air to coagulate, generate bubbles, or reduce the oxygen concentration in blood B. Furthermore, since the blood inlets 72a and 72b are defined on the same plane as the first step portion 70a, the amount of blood stored in the main body portion 30, that is, the amount of blood outside the patient's body should be reduced. It is possible and very suitable.

On the other hand, the blood B stored in the blood reservoir 36 is the blood outflow port.
Under the action of a pump (not shown) communicating with 84, it is intermittently delivered toward the human body. In this case, it is feared that the liquid level 86 of the blood B stored in the blood storage tank 36 will be resonantly oscillated by the intermittent delivery of the blood B by the pump. However, such resonance vibration is extremely effectively suppressed by the partition wall 82 arranged in the second step portion 70b of the blood reservoir 36.
That is, by disposing the partition wall 82 at a predetermined portion in the blood storage tank 36, the natural frequency of the system and the pulsation or pulsation frequency of the pump can be significantly different, and resonance vibration is suppressed. As a result, the liquid level 86 of the blood B becomes quiet, and the risk of air bubbles or the like being mixed in the blood B is significantly reduced. Further, since the fluctuation amount of the liquid level 86 due to pulsation or pulsation is small, the height of the liquid level 86,
That is, the amount of blood stored in the blood storage tank 36 can be easily and accurately confirmed from the outside. In addition, blood reservoir
Since the fluctuation of the blood B in the blood vessel 36 is effectively suppressed, the occurrence of vibration is extremely small, and there is no fear of causing unnecessary vibration in the entire device.

[Effects of the Invention] As described above, according to the present invention, in the extracorporeal blood circulation device in which the artificial lung and the blood reservoir are integrally formed, the blood flowing out from the artificial lung is expanded at the end portion and the bottom portion is formed. On the other hand, it is configured to flow into the blood reservoir via a blood inlet port that is open in the same plane and in a horizontal state. in this case,
The flow rate of the blood flowing out from the artificial lung is reduced in the expanded portion. Further, since the blood inlet is defined in the same plane as the bottom surface of the blood reservoir and in a horizontal state, the blood gently flows into the blood reservoir without jetting. As a result, there is no possibility that air bubbles will be mixed in the blood, and the blood will be stored in a very good state.

Although the present invention has been described above with reference to the preferred embodiment, the present invention is not limited to this embodiment, and is applicable to, for example, an extracorporeal blood circulation device in which a heat exchanger is a separate body. Naturally, various improvements and design changes can be made without departing from the scope of the present invention.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of an extracorporeal blood circulation device according to the prior art, FIG. 2 is a partial cross-sectional constitutional view of the extracorporeal blood circulation device according to the present invention, and FIG. 3 is a schematic configuration perspective view of FIG. 30 …… Main body, 32 …… Heat exchanger 34 …… Oxygenator, 36 …… Blood reservoir 46 …… Blood supply port, 68a, 68b …… Connecting conduits 72a, 72b …… Blood inlet 74a, 74b… … Mesh, 78 …… Urethane defoamer 84 …… Blood outflow port, B …… Blood

Claims (2)

[Claims] 1. An extracorporeal blood circulation device in which an artificial lung and a blood reservoir are integrally formed, wherein a blood inlet for allowing blood to flow from the artificial lung into the blood reservoir is gradually increased from the lower side to the upper side. An extracorporeal blood circulation device, characterized in that, after being expanded, the blood reservoir is opened horizontally in the same plane with respect to the bottom of the blood reservoir. 2. The device according to claim 1, wherein the blood reservoir has a bottom surface portion that smoothly inclines from the uppermost portion to the lowermost portion, and the blood inlet is opened at the bottom portion of the uppermost portion. Extracorporeal blood circulation device.