JPH0453565A - Bubble removing method and device for device having liquid passage - Google Patents

Abstract

PURPOSE:To remove the bubbles attached to a fluid passage within a short time without requiring complicated operation by intermittently sending a liquid in the liquid passage of a device. CONSTITUTION:Ringer's solution in a vessel 37 is sent into a centrifugal pump 33 from the inlet port 39 of the centrifugal pump 33 through a branched pipe 43 and a tube 41, energized by a rotating body in the centrifugal pump 33, discharged from a discharge hole 35, and sent to the blood inflow port 17 of an oxygenator 1. The discharge hole 35 of the centrifugal pump 33 is provided on the top part of the centrifugal pump 33. Namely, the rotating shaft of the centrifugal pump 33 is horizontally provided, and the discharge hole 35 is provided on the top part and in the tangential direction to the circular housing inner surface of the centrifugal pump 33, whereby, when the centrifugal pump 33 is intermittently driven, the bubbles collected in the central direction of the rotating body in the centrifugal pump 33 come up to the surface during stopping the centrifugal pump 33 and are easily discharged from the discharge hole 35.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for removing air bubbles in a device having a liquid flow path and the device, and more specifically, to a method for removing air bubbles in a device having a liquid flow path, and more specifically, to The present invention relates to a method for removing air bubbles from a blood flow path, etc., and an apparatus directly used for carrying out the method.

[Prior Art] Generally, before using a medical device such as an artificial lung, a so-called briming operation is required to fill a blood flow path with Ringer's solution or the like.

In particular, in the blood flow path of the extracorporeal circulation circuit of an artificial lung, there are many complicated and narrow flow paths such as hollow fiber membranes, tubes, and connectors, so when brimming, it is necessary to remove air bubbles that adhere to these flow paths. This is extremely important work.

Conventional methods for briming include gently flowing Ringer's solution into an oxygenator at a low flow rate or using a liquid pump to flow it in a steady flow to prevent the generation of new air bubbles. is being carried out.

[Problem to be solved by the invention] However, such a method requires a high degree of skill and a long time, and is not suitable for EBS (Emergenc...
y Bypath System), that is, blood is removed from the patient's femoral vein at the scene of the onset of the disease,
The procedure involves performing auxiliary circulation by returning blood from the femoral artery after passing through a pump and an oxygenator, and as this is an emergency procedure, the extracorporeal circulation circuit of the oxygenator is ready for use as soon as possible. You have to set it up like this,
The conventional briming operation, which is complicated and takes a long time, has been a major obstacle.

The present invention has been made in view of the above problems, and does not require complicated operations. The object is to provide a method by which air bubbles can be removed, as well as a device used for its implementation.

The inventor of the present invention has discovered that, contrary to the conventional wisdom of flowing a steady flow into the liquid channel using a liquid pump during briming, the present inventor has instead used an intermittent flow, which is difficult to remove. The inventors discovered the surprising fact that even the minute air bubbles present in the liquid flow path can be efficiently removed, leading to the completion of the present invention.

[Means for Solving the Problems] The present invention achieves the above object by intermittently flowing a liquid into a liquid flow path of a device having a liquid flow path and removing air bubbles present in the liquid flow path. A method for removing air bubbles in an apparatus having a liquid flow path, characterized by:

Furthermore, the present invention provides a device having a liquid flow path including a liquid inlet, a liquid flow path, and a liquid outlet; and a device having the liquid flow path, which is disposed upstream of the device having the liquid flow path. A liquid flow system comprising: a liquid transfer means for transferring a liquid to a liquid flow path through a liquid inlet; and a liquid transfer adjustment means for intermittently transferring the liquid to the liquid flow path. It consists of a device with a channel.

Further, by configuring at least a portion of the liquid flow path from a wall surface that allows gas to pass through but not liquid, the device having the liquid flow path itself can serve as a defoaming means.

Furthermore, by arranging the defoaming means downstream of the device having the liquid flow path, the defoaming method can be performed more quickly.

In addition, by arranging a small-diameter flow path section on the downstream side of the device that has a liquid flow path to increase the pressure of the liquid passing through the liquid flow path of the device that has a liquid flow path, bubble removal can be efficiently performed. It can be carried out.

Furthermore, by arranging a small-diameter flow path section downstream of the defoaming means to increase the pressure of the liquid passing through the defoaming means, the defoaming means can efficiently remove bubbles in a short time. be able to.

[Operation] When using the device according to the present invention, first, a container containing Ringer's solution is connected upstream of the pump, which is the liquid transfer means.

Next, the liquid pump is driven to send Ringer's solution into a liquid flow path of a device having a liquid flow path, such as an artificial lung.

At this time, Ringer's solution is intermittently pumped into the liquid flow path at predetermined time intervals and in a predetermined amount by a liquid pump.

In this way, by passing Ringer's solution intermittently into the liquid channel, the air bubbles attached to the inner surface of the liquid channel are removed from the inner surface of the liquid channel depending on the strength and weakness of the flow of Ringer's solution, and the air bubbles are removed from the inner surface of the liquid channel, and the air bubbles are removed from the inner surface of the liquid channel. removed from the device.

[Example] Hereinafter, the present invention will be explained in detail based on illustrated embodiments.

FIG. 1 shows a bubble removal device of an apparatus having a liquid flow path according to the present invention.

In this example, an artificial lung 1 is used as the device having a liquid flow path.

In the present invention, devices having a liquid flow path including a liquid inlet, a liquid flow path, and a liquid outlet include, in addition to the above-mentioned artificial lung, an artificial kidney, an artificial liver, an infusion set, a blood transfusion set, a filter, and a blood separator. , catheters, various tubes, and other medical devices or instruments having flow paths through which liquids such as blood and infusion agents flow.

Furthermore, the present invention is applicable not only to these medical devices but also to industrial products such as water purifiers as long as they have a liquid flow path.

The artificial lung 1 is shown in FIG. 5 as a partial cross section.

In the figure, 3 is a housing, and annular mounting covers 7 and 9 are attached to both ends of the cylindrical main body 5 of the housing 3.

Inside the housing 3, there are a large number of devices spread throughout the housing, for example io
, ooo~60,000 porous hollow fiber membranes 11 crimped at a predetermined ratio are arranged in parallel and spaced apart from each other along the axial direction of the housing 3. Both ends of this porous hollow fiber membrane 11 are connected to mounting covers 7 and 9.
Inside, each opening is supported in a liquid-tight manner by a partition wall 13 made of polyurethane or the like in an unobstructed state.

Further, the partition wall 13 is configured such that the outer circumferential surface of the porous hollow fiber membrane 11 and the inner surface of the housing 3 constitute a blood chamber 15 corresponding to the liquid flow path in the present invention, and is formed inside the porous hollow fiber membrane 11. It isolates the blood chamber 15 from an oxygen-containing gas circulation space (not shown).

A blood inlet 17 for supplying blood is provided on the side wall near the upper end of the housing 3.
On the side wall near the upper end, there is a blood outlet 1 for discharging blood.
9 is provided.

The inner surface of the cylindrical main body 5 of the housing 3 is provided with a tapered restricting portion 21 for diaphragm that protrudes toward the center in the axial direction.

The restricting portion 21 for restriction is formed integrally with the inner surface of the cylindrical body 5, and is a hollow fiber membrane composed of a large number of porous hollow fiber membranes 11 disposed inside the cylindrical body 5. The outer periphery of the bundle 23 is tightened.

As a result, the hollow fiber membrane bundle 23 is narrowed at the center in the axial direction, forming a narrowed portion 25.

Therefore, the filling rate of the porous hollow fiber membrane 11 differs in each part along the axial direction, and is highest near the central part.

Furthermore, an oxygen-containing gas inlet 27 and a gas outlet 29 are formed in the mounting covers 7 and 9, respectively.

Note that as the porous hollow fiber membrane 11, a microporous membrane made of porous olefin resin, for example, polypropylene or polyethylene can be used.

In this manner, during actual use of extracorporeal circulation, venous blood taken out from the human body flows through the blood inlet 17 of the oxygenator 1 and comes into contact with the outer surface of the porous hollow fiber membrane 11. On the other hand, since oxygen-containing gas is flowing inside the porous hollow fiber membrane 11, oxygen is added to the blood through the many pores of the porous hollow fiber membrane 11 and flows out from the blood outlet 19. , blood is returned to the body's arteries.

Referring again to FIG. 1, the present invention will be explained.

In FIG. 1, the blood inlet 17 of the artificial lung 1 communicates via a tube 31 with the outlet 35 of a centrifugal pump 33, which corresponds to the liquid transfer means in the present invention.

On the other hand, further upstream of the centrifugal pump 33, a container 37 containing a liquid harmless to living organisms, such as Ringer's solution, is provided, and the container 37 is provided in the middle of a tube 41 connected to the inlet 39 of the centrifugal pump 33. They are communicated via a branch pipe 43.

Therefore, the Ringer's solution in the container 37 flows into the centrifugal pump 33 from the inlet 39 of the centrifugal pump 33 via the branch pipe 43 and the tube 41, and is urged by the rotating body in the centrifugal pump 33 and flows out from the outlet 35. It will be discharged and sent to the blood inlet 17 of the artificial lung 1.

Note that the discharge port 35 of the centrifugal pump 33 is preferably provided at the top of the centrifugal pump 33, as shown in FIG.

That is, by arranging the centrifugal pump 33 so that its axis of rotation is horizontal, and by providing the discharge port 35 at the top and tangentially to the inner surface of the circular housing of the centrifugal pump 33, the centrifugal pump 33 can be operated intermittently. This is because when the centrifugal pump 33 is driven, the air bubbles collected toward the center of the rotating body within the centrifugal pump 33 float to the surface while the centrifugal pump 33 is stopped and are easily discharged from the discharge port 35.

The air bubbles discharged from the discharge port 35 flow into the oxygenator 1 and pass through the numerous holes of the porous hollow fiber membrane 11 from the blood chamber 15 to the oxygen-containing gas inlet 27 and the gas outlet 29.
More of this will be dissipated into the outside air.

That is, in this case, the porous hollow fiber membrane 11 of the artificial lung 1 has the property of allowing gas to pass through but not allowing liquid to pass therethrough, and also constitutes a part of the blood chamber 15 which is a liquid flow path. The oxygenator itself also serves as a defoaming means.

Furthermore, since the Ringer's solution discharged from the centrifugal pump 33 flows into the oxygenator 1 from the blood inlet 17 located above the oxygenator 1 and flows out from the blood outlet 19 located below, air bubbles in the Ringer's solution It is trapped in the upper part of the oxygenator l and efficiently discharged from the pores of the porous hollow fiber membrane 11.

Next, FIG. 4 shows the internal structure of the centrifugal pump 33.

A rotating body 45 is disposed within the centrifugal pump 33, is driven by a motor (not shown), and rotates at a predetermined rotational interval and rotational speed under the control of a separately provided control circuit.

A plurality of radially curved blade members 47 are provided on the rotating body 45 and are integrated.

In this way, the blood that has flowed in from the inflow port 39 of the centrifugal pump 33 flows in from approximately the center of the rotating body 45, is pushed out in the circumferential direction by the blade member 47, is urged, and is discharged from the discharge port 35. be done.

In addition, although the above-mentioned example demonstrated the case where the centrifugal pump was used as a liquid transfer means, it is not limited to this and a so-called beristaltic liquid pump, such as a so-called roller pump or a finger pump, may be used.

Returning to FIG. 1 again, the centrifugal pump 33 includes:
A control circuit 49 is electrically connected and controls the drive of the centrifugal pump 33.

In the present invention, the centrifugal pump 33 has the control circuit 49
The ringer's solution is controlled to be driven intermittently by the discharge port 35, and Ringer's solution is intermittently delivered from the discharge port 35.

In this way, an intermittent flow of Ringer's solution is introduced into the oxygenator 1, which is a feature of the present invention.

The control circuit 49 constitutes a liquid transfer adjustment means in the present invention, and drives the motor of the centrifugal pump 33 intermittently by varying frequency, pulses, current, voltage, etc.

Note that the centrifugal pump 33 driven by the control circuit 49
The liquid that flows out from the
Small (means repeating something that becomes small).

Therefore, when reducing the flow rate sent out from the centrifugal pump 33, the centrifugal pump 33 is stopped or rotated at a low rotation speed.

On the other hand, when increasing the flow rate, it is best to increase the flow rate in a short period of time (the shorter the rise time, the stronger the flow of the liquid becomes, and the more efficiently bubbles can be removed).

The control circuit 49 may be provided with an adjustment switch so that the interval and strength of the intermittent drive can be arbitrarily selected from a plurality of preset values.

Further, the drive signal from the control circuit 49 may be processed by a microcomputer and sent out in conjunction with a flow rate sensor separately provided within the centrifugal pump.

For further simplification, the control circuit 49 is simply a manual ON
- It may consist of an OFF switch and a power source for driving the motor of the centrifugal pump 33.

In this case, the drive signal for intermittently driving the motor of the centrifugal pump 33 is sent by manually turning the switch ON and OFF, but as a result, the same bubble removal effect can be obtained, and this embodiment The present invention also encompasses the following.

Note that the flow rate of the intermittent flow of Ringer's solution discharged from the discharge port 35 by the centrifugal pump 33 under the control of the control circuit 49 is, for example, 0 to ICN2/min, and the intermittent interval is determined by the drive of the motor. The number of times is 20 times per minute, and the driving time per time is about 2 seconds.

FIG. 2 shows another example of the liquid transfer adjustment means.

The difference between the device shown in FIG. 2 and the device shown in FIG. 1 is that in the device shown in FIG. 2, the centrifugal pump 33 is not driven intermittently but continuously; The valve 51 repeatedly presses and opens the tube 31 via the tube 31, thereby introducing an intermittent flow of Ringer's solution into the blood inlet 17 of the oxygenator 1.

While the valve 51 is operating and the tube 31 is closed, the rotating body 45 of the centrifugal pump 33 is idle.

However, in this example, a roller pump cannot be used in place of the centrifugal pump 33.

This is because roller pumps transfer liquid by forcibly squeezing the tube from upstream to downstream, so if the flow path is blocked on the downstream side of the tube, the internal pressure of the tube increases and the tube This is because there is a risk of it bursting.

On the other hand, the valve 51 is configured to close and open the tube 31 by reciprocating up and down by the rotation of an eccentric cam 55 driven by a drive motor 53 that receives a control signal from the control circuit 49.

Note that the reciprocating movement of the valve 51 is not limited to this example, and may be performed using an electromagnetic solenoid or the like.

Thus, in this example, the control circuit 49, the drive motor 53, the eccentric cam 55, and the valve 51 constitute the liquid transfer adjustment means of the present invention.

In this example, the control circuit 49 can be configured to operate in the same manner as in the example described based on FIG. 1, and may be a manual ON/OFF switch as in the case of FIG.

In Figures 1 and 2, the blood outlet 1 of the artificial lung 1 is
A defoaming means 57 is provided downstream of the air filter 7 .

When the above-mentioned oxygenator 1 is used as a "device having a liquid flow path" in the present invention, the bubble removing means 57 is used to remove bubbles from the porous hollow fiber membrane 11 in the oxygenator 1, as described above. Since it also serves as a means, it is not necessarily necessary.

However, even in this case, it is preferable to provide the defoaming means 57 because the bubbles that could not be defoamed by the porous hollow fiber membrane 11 in the oxygenator 1 can also be removed.

On the other hand, the "device having a liquid flow path" in the present invention is not an oxygenator using the above-mentioned porous hollow fiber membrane, but an oxygenator using a silicone membrane, an artificial kidney, a catheter, etc., in which the blood flow path is a closed system and the outside air is removed. For devices that do not communicate with the air filter in any way, the bubble removing means 57 is necessary.

In the present invention, the intended purpose can be achieved by removing at least air bubbles from the liquid flow path of the "device having a liquid flow path"; This is because it is necessary to let them escape.

FIG. 6 shows the internal structure of the defoaming means 57.

Ringer's solution flowing from the liquid population 59 is passed through the defoaming means 57
After passing through the interior of the liquid and being debubbled, it flows out from the liquid outlet 61.

On the other hand, the defoaming means 57 has a large number of porous hollow fiber membranes 63 arranged in parallel.

Like the porous hollow fiber membrane 11 of the oxygenator 1, this porous hollow fiber membrane 63 can be formed from polypropylene or the like.

The porous hollow fiber membrane 63 is fixed at both ends within the housing of the bubble removal means 57 by partition walls 65 made of polyurethane or the like.

Liquid population 59 of the defoaming means 57 configured in this way
After bubbles are separated from the Ringer's solution flowing in by the porous hollow fiber membrane 63, the ringer's solution flows out from the liquid outlet 61.

On the other hand, the air separated by the porous hollow fiber membrane 63 is
It passes through the porous hollow fiber membrane 63, flows out from the gas outlet 67, and is dissipated into the outside air.

Note that the defoaming means 57 is not limited to the above-mentioned example, and may be a membrane filter made of a sintered body formed by heating and compressing polyethylene or a polyester resin aggregate coated with polyvinyl chloride, which allows gas to pass through but not liquid. It can also be configured using - etc.

In short, any material that can separate and remove only the gas present in the liquid is sufficient.

Furthermore, in FIGS. 1 and 2, a small-diameter flow path portion 69 is provided downstream of the bubble removal means 57.

This small-diameter flow path portion 69 has a small-diameter portion 71 in the middle of the flow path, as shown when cut in the axial direction in FIG. The diameter of the small diameter portion is, for example, approximately 2 mm.

Therefore, the Ringer's solution that has flowed in from the inlet lower part 3 of the small-diameter flow path section 69 encounters a large resistance when passing through the small-diameter part 71 on the way to the outlet lower part 5, and the pressure of the Ringer's solution on the upstream side of the small-diameter part 71 increases. . This increase in pressure is caused by the blood chamber 15 in the oxygenator 1 and the defoaming means 57.
This is transmitted to the Ringer's solution present in the fluid, increasing the pressure.

In this way, by increasing the pressure of Ringer's solution, the artificial lung
In this case, the efficiency of bubble separation by the porous hollow fiber membrane 11 is increased, and on the other hand, in the defoaming means 57, the separation of bubbles by the porous hollow fiber membrane 67 is promoted, and the bubbles are removed from Ringer's solution more quickly. It can be performed.

By providing the small-diameter flow path portion 69 in this manner, bubbles in the negative layer and the entire circuit can be removed efficiently and in a short time.

As shown in FIGS. 1 and 2, the Ringer's solution that has passed through the small diameter channel section 69 is returned to the centrifugal pump 33 via the tube 41 and is recirculated. Normally, in the illustrated example, by recirculating Ringer's solution and repeating the bubble removal operation by intermittent driving of the centrifugal pump 33 for 3 minutes, bubbles in the liquid flow path can be almost completely removed.

Note that the degree of reduction in the number of bubbles floating in Ringer's solution flowing through the circuit can be determined by separately disposing a bubble detector in the middle of the circuit.

Next, a method of using the bubble removing device according to the present invention will be explained step by step with reference to FIG.

First, the branch pipe 43 extending from the container 37 and the tube 41 are communicated with each other, and Ringer's solution in the container 37 is introduced into the tube 41.

Next, the control circuit 49 is powered on to generate a control signal.

The centrifugal pump 33 receives the control signal at a predetermined time interval,
Driven at a predetermined rotational speed, Ringer's solution that flows through the tube 41 from the inlet 39 is intermittently passed through the outlet 35.
more excreted.

Furthermore, Ringer's solution discharged from the discharge port 35 passes through the tube 31.

At this time, air bubbles adhering to the inner surface of the duplex 31 are removed by the force of the intermittent flow of Ringer's solution, and are carried to the oxygenator together with Ringer's solution.

Ringer's solution that flows in from the blood inlet 17 of the artificial lung 1 is
Bulkhead 13. to the blood chamber 15 formed by being surrounded by the outer peripheral surface of the porous hollow fiber membrane 11 and the inner surface of the housing 3;
It flows in together with the aforementioned removed air bubbles.

Since the non-gel liquid flows into the blood chamber 15 in an intermittent flow, the force of the flow, especially the energy when changing from a low flow rate to a high flow rate in a short period of time, causes the surface of the partition wall 13 constituting the blood chamber 15 to become porous. Air bubbles adhering to the outer surface of the hollow fiber membrane 11 and the inner surface of the housing 3 are removed and suspended in Ringer's solution.

Here, since the porous hollow fiber membrane 11 has a property of allowing gas to pass through but not allowing liquid to pass therethrough, air bubbles in the Ringer's solution are separated by the porous hollow fiber membrane 11.

The separated air passes through the porous hollow fiber membrane 11,
The oxygen-containing gas flows in through the oxygen-containing gas outlet 27 and the gas outlet 29 and is dissipated into the outside air.

On the other hand, the Ringer's solution from which air bubbles have been removed flows out from the liquid outflow port 19 of the oxygenator 1 and reaches the defoaming means 57 .

If there are bubbles that could not be removed by the oxygenator 1, they will be completely removed by the bubble removal means 57.

The Ringer's solution that has passed through the defoaming means 57 then passes through the small diameter channel section 69 .

As described above, the small-diameter flow path section 69 increases the internal pressure of Ringer's solution in the oxygenator 1 and the bubble removing means 57, thereby increasing the efficiency of separating and removing air bubbles.

The Ringer's solution that has passed through the small diameter channel section 69 is transferred to the tube 41.
It flows through the centrifugal pump 33 again and is recirculated.

At this time, air bubbles adhering to the inside of the tube 41 are removed and floated in Ringer's solution.

If there are bubbles that cannot be removed by the oxygenator l or by the removal means 57, they will be trapped by the removal means 57 etc. while being recirculated together with the air bubbles, and these bubbles will gradually be removed. will decrease.

After the air bubbles existing in the fluid flow path in the circuit are removed in this way, the bubble removing means 57 and the small diameter flow path portion 69 are separated from the connectors 81 and 83 together with the tubes.

Next, the other end of a catheter (not shown), one end of which is connected to the femoral vein of the human body, is connected to the connector 83, and the other end of the catheter (not shown) is connected to the connector 81, one end of which is connected to the femoral artery of the human body. The other end of the catheter (not shown) is connected and extracorporeal circulation is started.

In addition, since blood flows in from the blood inlet 17 located above the artificial lung 1 and flows out from the blood outlet 19 located below, even if there are air bubbles in the blood, they are trapped by the artificial lung 1. It cannot be sent to the human body.

(Test Example) A briming test was conducted using the bubble removing device according to the present invention shown in FIG.

First, Ringer's solution in the container 37 was introduced into the tube 41, the flow rate of the centrifugal pump 33 was set to 4β/min, and the centrifugal pump was driven.

Immediately after driving the centrifugal pump 33, an air bubble detector was used to detect air bubbles passing through the tube 31 between the centrifugal pump 33 and the oxygenator 1, and more than 600 air bubbles with a diameter of 20 pm or more were detected in 60 seconds. It was done.

After that, when the pump was driven steadily, no bubbles with a diameter of 20 μm or more were observed after 2 minutes (but when the circuit was tapped with forceps, 10 or more bubbles with a diameter of 20 μm or more were detected each time). It was done.

Next, the centrifugal pump 33 was turned ON and OFF every 3 seconds, and after driving the hole for 3 minutes with ON time of 2 seconds and OFF time of 2 seconds, the drive of centrifugal pump 33 was returned to steady flow. , I used forceps to hit the circuit, but the diameter was 2o.
1. No bubbles larger than Lm were detected.

Therefore, it was confirmed that air bubbles in the liquid flow path can be removed by performing briming with intermittent flow according to the present invention.

[Effects of the Invention] As detailed above, the present invention provides a method for intermittently flowing a liquid into a liquid flow path of a device having a liquid flow path to remove air bubbles present in the liquid flow path. This invention consists of a bubble removal method for a device having a liquid flow path, which is characterized by:

Furthermore, the present invention provides a device having a liquid flow path including a liquid inlet, a liquid flow path, and a liquid outlet; and a device having the liquid flow path, which is disposed upstream of the device having the liquid flow path. A liquid flow system comprising: a liquid transfer means for transferring a liquid to a liquid flow path through a liquid inlet; and a liquid transfer adjustment means for intermittently transferring the liquid to the liquid flow path. The device consists of a bubble removal device with a channel.

Therefore, according to the present invention, there is provided a method for removing air bubbles attached to a liquid flow path of a device having a liquid flow path such as an oxygenator, a tube, or a connector in a short time without requiring complicated operations; Apparatus for use in its implementation is provided.

Furthermore, by configuring at least a portion of the liquid flow path of a device having a liquid flow path from a wall surface that allows gas to pass through but not liquid, the device itself that has a liquid flow path, such as an artificial lung, can also serve as a defoaming means. This eliminates the need to separately provide a defoaming means, and allows the defoaming work to be carried out more quickly.

Furthermore, by providing a defoaming means downstream of the device having the liquid flow path, defoaming can be quickly performed.

In addition, by arranging a small-diameter flow path section on the downstream side of the device having a liquid flow path to increase the pressure of the liquid passing through the liquid flow path of the device having the liquid flow path, the liquid flow path can be expanded. It is possible to further improve the efficiency of defoaming in the device having the above-mentioned structure.

Further, by arranging a small-diameter flow path section downstream of the bubble removal means for increasing the pressure of the liquid passing through the bubble removal means, bubble removal by the bubble removal means is further promoted.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a bubble removing device for a device having a liquid flow path according to the present invention, and FIG. 2 is a diagram showing another example of a bubble removing device for a device having a liquid flow path according to the present invention. Figure 3 is a diagram showing how the oxygenator and centrifugal pump are connected, Figure 4 is a diagram showing the internal structure of the centrifugal pump, and Figure 5 is
FIG. 6 is a cross-sectional view of a part of the oxygenator, FIG. 6 is a cross-sectional view of the defoaming means, and FIG. 7 is a cross-sectional view of the small diameter flow path. (Explanation of codes for main parts) - Artificial lung (equipment with liquid flow path) - Centrifugal pump (liquid transfer means) - Control circuit (liquid transfer adjustment means) - Bubble removal means - Small diameter flow path Figure 1 7 Figure 5 Figure 3 Figure 6 Figure 7

Claims (6)

[Claims] (1) A method for removing air bubbles in a device having a liquid flow path, the method comprising: intermittently flowing a liquid into a liquid flow path of the device having a liquid flow path to remove air bubbles present in the liquid flow path. . (2) A device having a liquid flow path including a liquid inlet, a liquid flow path, and a liquid outlet; and a device having the liquid flow path, which is disposed upstream of the device having the liquid flow path. A liquid flow path comprising: a liquid transfer means for transferring liquid to the liquid flow path via an inlet; and a liquid transfer adjustment means for intermittently transferring the liquid to the liquid flow path. Bubble removal device of the device with. (3) The device according to claim 2, wherein the liquid channel is constituted by a wall surface that allows gas to pass through but not liquid. (4) The device according to claim 2 or 3, wherein a defoaming means is provided downstream of the device having the liquid flow path. (5) Claim 3, wherein a small diameter flow path section for increasing the pressure of the liquid passing through the liquid flow path of the device having the liquid flow path is disposed downstream of the device having the liquid flow path. The device described. (6) The apparatus according to claim 4, further comprising a small-diameter flow path section provided downstream of the bubble removing means for increasing the pressure of the liquid passing through the bubble removing means.