JP2003093503A - Automatic degassing system for blood circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus capable of stably keeping a state not substantially generating the contact part of blood and air for a relatively long time in an extracorporeal circulation blood circuit, and a method using the same. SOLUTION: This blood circuit system is constituted so that a degassing chamber is connected to the extracorporeal circulation blood circuit on the way thereof and a detection means for detecting air bubbles and a discharge line for discharging air bubbles are provided to the degassing chamber and the supply line connected to a container filled with a blood inert substance is provided to the terminal to the blood circuit and a blood compatible fluid layer is provided between a blood layer and an air layer in the degassing chamber. Air bubbles accumulated in the degassing chamber are detected by the detection means to be discharged through the discharge line and the old blood compatible fluid is discharged and, after degassing, the fresh blood inert substance is introduced from the supply line to stably keep the degassing in the degassing chamber and such a state that blood and air are not substantially brought into contact with each other in the degassing chamber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-circuit bubble removal system and method for an extracorporeal blood circuit.

[0002]

2. Description of the Related Art In an extracorporeal circulation blood circuit such as a hemodialysis circuit or a cardiopulmonary blood circuit, it is an important medical problem that the blood flowing in the circuit does not deteriorate and functions stably. Is. A major factor in the deterioration of blood in the circuit is coagulation due to contact between blood and air.

Conventionally, in hemodialysis or the like, it has been general that minute air bubbles mixed with blood in a circuit are trapped by a dedicated chamber (deaeration chamber). These bubbles usually accumulate in the upper part of the chamber and become an air layer over time, forming an interface where air and blood come into contact with each other, and blood coagulates at this interface. The clot generated at the interface may fall off, mix into the blood flowing in the circuit, collect in various parts of the circuit, block the flow path, and cause serious consequences such as discontinuation of dialysis. .

Therefore, a method of separating the blood and the air layer by providing a layer of a blood compatible fluid, for example, physiological saline solution so that the blood does not come into direct contact with the air layer is effective.

However, in continuous blood purification therapy which is carried out for a long time of 24 to 72 hours, the air layer increases in the chamber with the passage of time during the therapy, and the physiological saline solution which is constantly in contact with blood slightly increases. Blood mixes and turns red. As a result, blood clots are generated at the interface between the air layer and the physiological saline that is colored red.

[0006]

In view of the above circumstances, an object of the present invention is to provide an extracorporeal circulation blood circuit such as a hemodialysis circuit, an artificial heart-lung blood circuit, and the like, particularly a blood circuit intended for long-term use. An object of the present invention is to provide an apparatus and a method thereof that can stably maintain a state in which a contact portion between blood and air is not substantially generated for a relatively long time.

[0007]

In order to solve the above-mentioned problems, an extracorporeal circulation blood circuit according to the present invention includes a main line provided for circulating blood and air bubbles mixed in the blood in the middle of the main line. A blood circuit including a deaeration chamber for trapping, wherein the deaeration chamber is provided with detection means for detecting bubbles in the deaeration chamber, and intervenes so as to interrupt the blood layer and the air layer in the deaeration chamber. A blood circuit provided with a supply line for introducing a blood-compatible fluid to be connected to the deaeration chamber, and an exhaust line for discharging air in the deaeration chamber or the blood-compatible fluid to the deaeration chamber System. Thereby, the air bubbles (air) accumulated in the degassing chamber are detected by the detecting means, and the degassing is performed through the discharge line, and the old blood compatible fluid is discharged, and after degassing, fresh blood is supplied from the supply line. Provided are a degassing inside a degassing chamber and a stable blood non-contact state between blood and air inside the degassing chamber by introducing a compatible fluid, and a degassing method by the blood circuit system. . Furthermore, the present invention solves the above problems by the following features (1) to (16).

(1) In the extracorporeal circulation blood circuit, a deaeration chamber connected to the main line, a detection means provided to detect bubbles in the deaeration chamber, and an upper part of the deaeration chamber are connected. An exhaust line provided to exhaust air bubbles and / or blood compatible fluid within the degassing chamber, and also provided for introducing blood compatible fluid into the degassing chamber, also connected to the upper portion of the degassing chamber A blood circuit system comprising a supply line.

(2) The blood circuit system according to (1) above, wherein negative pressure loading means is provided in the discharge line.

(3) The blood circuit system as described in (1) or (2) above, wherein the discharge line and the supply line are respectively provided with opening / closing means.

(4) The above-mentioned (1) to (3), further comprising a control means which is interlocked with the detection means and which controls the opening / closing of each opening / closing means provided in the discharge line and the supply line.
The blood circuit system according to any one of 1.

(5) The blood circuit system according to any one of (1) to (4) above, wherein the blood compatible fluid is a physiological liquid.

(6) The blood circuit system according to (5) above, wherein the physiological fluid is a dialysate, physiological saline, or phosphate buffer (PBS).

(7) The blood circuit system according to any one of the above (1) to (4), wherein the blood compatible fluid is an inert gas.

(8) The blood circuit system according to (7), wherein the inert gas is nitrogen gas, helium gas, or argon gas.

(9) A method for degassing air bubbles in blood flowing in a circuit of an extracorporeal circulation blood circuit system, wherein the circuit is provided with a degassing chamber and an exhaust line connected to the degassing chamber is provided. Along with, in the extracorporeal circulation blood circuit system which is also connected to the degassing chamber and is provided with a supply line for introducing the blood compatible fluid into the degassing chamber, a step of detecting air bubbles in the degassing chamber with a detecting means, A blood circuit degassing method comprising: a step of discharging air bubbles and / or a blood compatible fluid from a discharge line side; and a step of introducing a blood compatible fluid from a supply line.

(10) In the extracorporeal circulation blood circuit system in which negative pressure load means is provided in the discharge line of the extracorporeal circulation blood circuit system according to the above (9), the negative pressure load means is controlled to form a bubble and / or a blood compatible fluid. A method of degassing a blood circuit, comprising the step of discharging

(11) The supply line of the extracorporeal circulation blood circuit system according to any one of (9) or (10) above,
An extracorporeal circulation blood circuit system in which opening and closing means are respectively provided in the discharge lines, further comprising a step of controlling each opening and closing means.

(12) In the extracorporeal circulation blood circuit system in which the control means is provided in the extracorporeal circulation blood circuit system according to any one of (9) to (11), a step of automatically controlling each step of the deaeration A blood circuit degassing method, further comprising:

(13) A blood circuit degassing method, wherein the blood-compatible fluid according to any one of (9) to (12) is a physiological liquid.

(14) The physiological liquid described in (13) above is a dialysate, physiological saline, or phosphate buffer (P
BS) is a blood circuit degassing method.

(15) A blood circuit degassing method, wherein the blood compatible fluid according to any one of (9) to (12) is an inert gas.

(16) A method for degassing a blood circuit, wherein the inert gas according to (15) above is nitrogen gas, helium gas or argon gas.

This makes it possible to discharge air bubbles (air) in the blood circuit in the extracorporeal circulation blood circuit and stably maintain a state in which blood and the air layer are not substantially in contact with each other via the blood compatible fluid. It becomes possible to do.

The "blood compatible fluid" used in the blood circuit automatic degassing system described in the present specification means that the blood is inert such as hemolysis and coagulation. Means any fluid. In addition, “physiological liquid” and “inert gas” are defined as “physiological liquid” and “inert gas”, respectively, which are liquids in “blood compatible fluid”. .

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION The details of the extracorporeal blood circuit according to the present invention will be described below with reference to the accompanying drawings. First, a schematic configuration will be described with reference to FIG.
FIG. 1 is a schematic diagram when the blood circuit system according to the present invention is used for hemodialysis. The blood circuit system according to the present invention is connected to a blood port of a dialyzer 12, and is installed by a blood pump 11 in the middle of a main line 2 provided to circulate blood via a deaeration chamber 1.

When blood mixed with bubbles flows into the degassing chamber 1 through the main line 2, the bubbles rise by their buoyancy and are captured in the upper part of the degassing chamber 1. In addition, the degassing chamber 1 has a first
A detection unit 61 is provided and installed so as to detect bubbles in the degassing chamber 1.

Above the degassing chamber 1, a discharge line 3 for degassing the air in the chamber is connected. The discharge line 3 is provided at its end with a drain chamber 9 for collecting air discharged from the degassing chamber, and a first opening / closing means 71 for opening / closing the discharge line 3 is provided in the middle thereof.

Further, above the deaeration chamber 1, a supply line 4 for introducing a blood compatible fluid into the chamber.
Is provided. The supply line 4 is provided with a container for storing the blood compatible fluid at its end, and a first opening / closing means 71 for opening / closing the supply line 4 is provided in the middle thereof.

Further, in the blood circuit system shown in FIG. 1, the first opening / closing means 71 and the second opening / closing means 7 are provided by the signals from the first detecting means 61, (second detecting means 62).
The control means 10 controls the driving of the opening / closing operation.

According to the above construction, the blood flowing in the blood circuit is introduced into the deaeration chamber 1, and the bubbles mixed in the blood move to the upper part of the deaeration chamber 1 by its own buoyancy. With the passage of time, some bubbles accumulate in the upper part of the degassing chamber 1 and form an air layer. This air layer is detected by the first detection means 61, and the negative pressure load means 8 provided in the middle of the discharge line 3 applies negative pressure load to the discharge line 3 to discharge the air layer in the deaeration chamber 1. At the same time, the old blood compatible fluid that was in contact with the blood layer in the deaeration chamber 1 is discharged to the drain chamber 9. Next, from the supply line 4 provided above the degassing chamber 1, a new blood compatible fluid filled in the container 5 is caused to flow to the degassing chamber 1 side through the supply line 4, and the new blood compatible fluid is placed in the degassing chamber 1. Form the layers. As a result, the blood in the blood chamber 1 is brought into a non-contact state with the air via the blood compatible fluid, and it becomes possible to prevent blood clotting.

Further, in the blood circuit of the present invention, it is preferable that negative pressure load means is provided in the discharge line and the bubbles accumulated in the deaeration chamber are discharged through the discharge line. As an example of the negative pressure loading means, any method such as a general vacuum pump, a roller pump, a peristaltic pump,
Since the effect of the invention can be achieved, it is not particularly limited.

In the blood circuit of the present invention, it is preferable that the discharge line and the supply line are respectively provided with opening / closing means. Further, it is preferable that the opening / closing means is a clamp of a pressing and sandwiching type so that each line can be opened and closed. The blood circuit is usually composed of a flexible tubular member. Therefore, a simple opening / closing mechanism that closes the inner cavity of the tubular member by applying pressure from the outside of the tubular member, closes the circuit, and releases the pressure to open the circuit is a preferable mode. . Further, it is preferable that the opening / closing means provided in the discharge line is integrally formed with the negative pressure load means also provided in the discharge line as described above because the structure is simplified.

In the blood circuit of the present invention, the control means 10 is used to control each opening / closing means in association with the signal from each bubble detecting means, whereby a series of degassing steps can be automatically performed. It is preferable that the structure be made possible.

Further, in the blood circuit of the present invention, the blood compatible fluid passing between blood and air is preferably a physiological liquid. Specific examples of the physiological liquid include dialysate used for hemodialysis, physiological saline, phosphate buffer (PBS) and the like. Of these, physiological saline is a more preferable embodiment because it is inexpensive and easily available.

The effect of the present invention can also be achieved by using an inert gas for the blood compatible fluid used in the blood circuit of the present invention. As a specific example of the inert gas, nitrogen gas, helium gas, argon gas or the like, which is chemically and biologically inert at room temperature and is relatively easy to handle, is a preferable embodiment. Among them, nitrogen gas is a more preferable embodiment because it is inexpensive and easily available.

The detecting means used in the blood circuit of the present invention is provided on the outer peripheral portion of the deaeration chamber so as to detect the bubbles generated in the deaeration chamber.
Various detection methods are included in the mechanism for detecting bubbles of the detection means. That is, a method of directly detecting air bubbles (air layer) by a detection means, or the air layer increases in the upper part of the degassing chamber due to the passage of time, which causes the interface between the blood layer and the blood compatible fluid layer or the air layer and blood A method of detecting the drop of the interface with the compatible fluid layer by a detection means may be mentioned, but the effect of the present invention can be achieved by any method.

Further, the detecting means used in the blood circuit according to the present invention can change the mounting position in the degassing chamber 1 according to the desired amount of the degassing air layer. That is, in order to set a large amount of degassing air, a position to be attached to the degassing chamber 1 may be provided relatively far from the top of the degassing chamber 1, and the degassing air amount is set to be small. In this case, the position to be mounted on the degassing chamber 1 may be provided relatively close to the top of the degassing chamber 1. As described above, the bubble detecting means used in the present invention can easily adjust the amount of degassed air. Further, the bubble detecting means used in the present invention may be any other known type of sensor such as an optical sensor or an ultrasonic sensor.

Although the embodiment for hemodialysis has been described with reference to FIG. 1 as described above, the blood circuit system according to the present invention is not limited to this, and a blood circuit for artificial heart-lung, etc. It is also applied to the extracorporeal circulation blood circuit.

[0040]

The details of the degassing mechanism of the blood circuit system according to the present invention will be described with reference to FIGS. 2 to 8 are schematic views in each step during operation when the blood circuit system according to the present invention is used during hemodialysis. In addition, it is an example when the blood compatible fluid is physiological saline. In the two types of slanted lines shown on the main line 2, the degassing chamber 1, the exhaust line 3, and the supply line 4, the sparse slanted lines indicate physiological saline and the dense slanted lines indicate blood.

First, as shown in FIG. 2, when hemodialysis operation is started in a hemodialyzer (not shown), blood flows from the main line 2 and is provided on the upper side of the degassing chamber 1. Blood is introduced from the blood inlet, the deaeration chamber 1 is filled with blood, and the blood is discharged from the blood outlet provided at the bottom of the deaeration chamber 1.
Is returned to the hemodialyzer (not shown). At this time, in the deaeration chamber 1, blood is located in the lower layer and physiological saline is located in the upper layer. Further, the interface between the blood layer and the physiological saline layer is provided so as to be located below the position of the detecting means 6 provided on the outer peripheral portion of the degassing chamber 1, and the detecting means 6 detects the physiological saline layer. It is provided for monitoring. At this time, the first opening / closing means 71 and the second opening / closing means 72 are in a closed state.

Next, as shown in FIG. 3, when a bubble generated in the blood circuit is introduced into the degassing chamber 1 from the main line 2 due to some factor, the bubble moves to an upper part of the degassing chamber 1. It will accumulate. With the passage of time during the hemodialysis operation, the air bubbles accumulated in the upper part of the degassing chamber 1 gradually become an air layer 13, and an interface between the air layer 13 and blood is generated in the upper part of the degassing chamber 1. When air bubbles are further accumulated and the air layer 13 becomes large, the interface between the air layer 13 and blood is lowered, and when the position of the interface reaches a predetermined position, the detection means 6 outputs a signal, and the signal is sent to the control means 10. Send.

Further, in the deaeration chamber during the hemodialysis operation, blood may be mixed in the physiological saline layer. At this time, since the coagulation occurs at the interface between the physiological saline layer mixed with blood and the air layer located above the physiological saline layer, the physiological saline layer mixed with blood and colored red is detected by the detection means 6
To detect. Then, similarly to the above, the detection means 6 outputs a signal and transmits the signal to the control means 10.

Next, as shown in FIG. 4, the control means 10 sends a signal to the first opening / closing means 71 (in this embodiment, an example of integrally forming the opening / closing means and the negative pressure load means). Then, the first opening / closing means 71 is opened and a negative pressure is applied to the discharge line 3. Then, the air 13 in the deaeration chamber 1 is transferred through the discharge line 3 together with the physiological saline in the vicinity thereof.

Next, as shown in FIG. 5, when the air 13 and the physiological saline are all transferred to the discharge line 3, the control means 10 stops the negative pressure load operation of the discharge line, and the first opening / closing means 71. And a signal to open the second opening / closing means 72.

Next, as shown in FIG. 6, the second opening / closing means 72
Is opened and the physiological saline filled in the container 5 is started to be introduced into the degassing chamber 1 through the supply line 4.

Next, as shown in FIG. 7, when the physiological saline is introduced into the degassing chamber 1, the interface between the physiological saline and the blood is lowered to a predetermined position (the detecting means set at the initial stage). When it reaches the position (below 6), the control means 10 transmits a signal, closes the second opening / closing means 72, and stops the introduction of physiological saline. Thus, a series of degassing steps is completed.

Regarding the flow rate control of the discharge from the degassing chamber 1 to the drain chamber 9 or the introduction from the container 5 to the degassing chamber 1, the control means 10 controls the first opening / closing means 71 and the second opening / closing means 72. The opening / closing control is preferably a temporal control in which the discharge / introduction amount of air and physiological saline and the flow velocity in each line are calculated and the opening / closing control is performed for a preset time. It is also possible to control so that only the air in the deaeration chamber 1 is discharged from the discharge line 3 by setting the control means 10.

In the present embodiment, an example of the blood compatible fluid is physiological saline, but other physiological liquids such as dialysate and phosphate buffer (PBS) used for hemodialysis are used.
The effects of the present invention can also be achieved in such cases.

Further, the effect of the present invention can be achieved not only with a physiological liquid containing physiological saline as an example of the blood compatible fluid, but also with an inert gas such as nitrogen gas, helium gas or argon gas. is there.

From the above, even if air bubbles or an air layer are generated in the deaeration chamber 1 in the blood circuit, the blood compatible fluid is interposed between the blood layer and the air layer, so that blood can be generated in the blood circuit. It is possible to maintain the state in which the air is brought into contact with the surface so as not to substantially occur. Further, the detection means 6 detects air bubbles (air) generated in the deaeration chamber and an old blood compatible fluid, and a negative pressure load is generated from the side of the discharge line 3 extending from the deaeration chamber 1 to forcibly. The non-contact state between the blood and the air layer can be stably maintained for a long time by discharging the blood and the new blood compatible fluid into the degassing chamber. Further, by using the control means in these series of steps, it can be automatically performed.

[0052]

According to the blood circuit automatic degassing system of the present invention, the blood compatible fluid layer is substantially provided between the blood layer and the air layer in the degassing chamber provided in the middle of the blood circuit. It is possible to maintain the state where blood and air do not come into contact with each other. As a result, the blood flowing through the extracorporeal circulation blood circuit does not clot during the operation, and the extracorporeal circulation blood circuit can be safely operated for a long time.

[Brief description of drawings]

FIG. 1 is a schematic diagram when the blood circuit system according to the present invention is used for hemodialysis.

FIG. 2 is a schematic view of the blood circuit system according to the present invention when extracorporeal blood circulation is started.

FIG. 3 is a schematic diagram when air bubbles are detected during operation of the blood circuit system according to the present invention.

FIG. 4 is a schematic diagram of the blood circuit system according to the present invention at the start of deaeration operation.

FIG. 5 is a schematic view of the blood circuit system according to the present invention when deaeration operation is stopped.

FIG. 6 is a schematic view of a blood circuit system according to the present invention when supply of a blood compatible fluid is started.

FIG. 7 is a schematic view of the blood circuit system according to the present invention when the supply of the blood compatible fluid is stopped.

[Explanation of symbols]

1. Degassing chamber 2. Main line 3. Discharge line 4. Supply line 5. container 6. Detection means 71. First opening / closing means 72. Second opening / closing means 8. Negative pressure load means 9. Drain chamber 10. Control means 11. Blood pump 12. Dialyzer 13. Air or air layer

Claims (16)

[Claims] 1. In an extracorporeal circulation blood circuit, a deaeration chamber connected to a main line, a detection means provided to detect bubbles in the deaeration chamber, and an upper part of the deaeration chamber, An exhaust line provided to exhaust air bubbles and / or blood compatible fluid in the degassing chamber, and also provided to connect the upper part of the degassing chamber to introduce the blood compatible fluid into the degassing chamber A blood circuit system comprising a supply line. 2. The blood circuit system according to claim 1, wherein negative pressure loading means is provided in the discharge line. 3. The blood circuit system according to claim 1, wherein the discharge line and the supply line are respectively provided with opening / closing means. 4. The control means for controlling the opening / closing of each opening / closing means provided in a discharge line and a supply line in conjunction with the detection means, as claimed in any one of claims 1 to 3. Blood circuit system. 5. The blood circuit system according to any one of claims 1 to 4, wherein the blood compatible fluid is a physiological liquid. 6. The blood circuit system according to claim 5, wherein the physiological fluid is dialysate, physiological saline, or phosphate buffer (PBS). 7. The blood circuit system according to claim 1, wherein the blood compatible fluid is an inert gas. 8. The blood circuit system according to claim 7, wherein the inert gas is nitrogen gas, helium gas, or argon gas. 9. A method for degassing air bubbles in blood flowing in a circuit of an extracorporeal circulation blood circuit system, the circuit comprising a degassing chamber and an exhaust line connected to the degassing chamber. In the extracorporeal circulation blood circuit system, which is also connected to the degassing chamber and is provided with a supply line for introducing a blood compatible fluid into the degassing chamber,
Blood comprising: a step of detecting air bubbles in the degassing chamber by a detection means; a step of discharging air bubbles and / or a blood compatible fluid from a discharge line side; and a step of introducing a blood compatible fluid from a supply line. Circuit degassing method. 10. An extracorporeal circulation blood circuit system in which a negative pressure load means is provided on a discharge line of the extracorporeal circulation blood circuit system according to claim 9, wherein the negative pressure load means is controlled to form a bubble and / or a blood compatible fluid. A method of degassing a blood circuit, comprising the step of discharging 11. A step of controlling each opening / closing means in an extracorporeal circulation blood circuit system in which an opening / closing means is provided in each of a supply line and a discharge line of the extracorporeal circulation blood circuit system according to claim 9 or 10. A blood circuit degassing method, further comprising: 12. An extracorporeal circulation blood circuit system according to any one of claims 9 to 11, wherein the extracorporeal circulation blood circuit system is provided with a control means, further comprising a step of automatically controlling each step of the deaeration. A blood circuit degassing method comprising: 13. A blood circuit degassing method, wherein the blood-compatible fluid according to any one of claims 9 to 12 is a physiological liquid. 14. The physiological fluid according to claim 13 is a dialysate, physiological saline or phosphate buffer (PB).
S) is a blood circuit degassing method. 15. A blood circuit degassing method, wherein the blood compatible fluid according to any one of claims 9 to 12 is an inert gas. 16. A method of degassing a blood circuit, wherein the inert gas according to claim 15 is nitrogen gas, helium gas or argon gas.