JPH0225408Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement in an extracorporeal circulation circuit used when blood or the like is circulated extracorporeally to remove a target substance from the blood.

(Prior Art and its Problems) Systems have been widely known, such as artificial dialysis and plasma exchange, in which blood is drawn from a patient and circulated outside the body, and unnecessary substances are removed using a filter membrane during the process.

FIG. 5 shows a schematic diagram of a conventional hemodialysis system as an example, in which a blood pump 21 is connected to a circuit 2 from a shunt 20 connected to a patient's blood vessel.
After introducing the blood into the dialyzer 24 for dialysis treatment, the blood is introduced into the drip chamber 25.
After that, air is removed and foreign matter is removed, and then blood is returned to the patient through the shunt 26.

As shown in FIG. 6, for example, the drip chamber 25 has a filter 26 and a blood outlet tube 27 attached to the lower part of the chamber body, and a cap 30 to which a blood inlet tube 28 and a monitor tube 29 are connected to the upper part of the chamber body. It has a structure. In addition, as shown in FIG. 7, a blood inlet tube 28 is provided at the upper side of the chamber body, but in any case, the conventional drip chamber has a blood inlet tube 28 of 1/3 to 1/2 inch from the top. Blood is stored inside, leaving an air layer of about 1/4 inch, and monitor tube 2 to monitor changes in this air layer.
The pressure gauge 31 connected to 9 measures the pressure inside the circuit.

However, the presence of the above-mentioned air space causes thrombus formation. For this reason, in the past, a large amount of anticoagulant was introduced into the circuit, but in recent extracorporeal blood circulation therapy, there is a tendency to use as little or no anticoagulant as possible. That is,
Normally, anticoagulants are used when blood is processed through extracorporeal circulation, such as hemodialysis or plasma exchange, but anticoagulants are not recommended after surgery or in patients with bleeding diathesis, which can sometimes lead to fatal bleeding. This is to provoke.
Therefore, in such cases, no anticoagulant is used at all, or even if it is used, only a very small amount can be administered.

In order to prevent such blood clots, it is necessary to fill the entire drip chamber with blood to prevent the formation of an air layer, but this will cause the problem that the pressure inside the circuit cannot be measured through the monitor tube 29. Become.

The present invention was proposed as a result of repeated studies to solve these problems.

(Means for Solving the Problems) In the present invention, as shown in FIGS. 1 to 4 corresponding to the embodiment, a drip chamber 7 is provided in the middle of the extracorporeal fluid circulation circuit, and the upstream circuit of this drip chamber is A double-tube type pressure sensor 6 is provided at . Further, a filter 8 is attached to the bottom of the drip chamber 7, and a filter 8 is attached to the bottom of the drip chamber 7.
A degassing line tube 12 is provided in the upper part of the degassing line tube 12.

The body fluid inlet portion 11 of this drip chamber is provided on the side of the chamber.

Furthermore, the lower part of the drip chamber body is inclined inwardly at an angle of 10 DEG to 60 DEG with respect to the vertical axis of the filter 8.

The entire drip chamber is filled with body fluid, and the degassing line tube 12 is filled with a liquid such as physiological saline.

(Function) Inside the drip chamber 7, there is a side inlet 11.
Body fluids are introduced into the body, and the whole body is filled with body fluids. When air bubbles enter the drip chamber 7, the air bubbles escape from the degassing line tube 12. Since the degassing line tube 12 is filled with physiological saline or the like, the body fluid in the drip chamber 7 does not come into direct contact with the outside air, thereby preventing the formation of blood clots and the invasion of bacteria. In addition, the pressure in the circuit is determined by the gap 18 of the double pipe pressure detector 6 provided on the upstream side of the drip chamber 7.
The change in pressure is detected via the pressure monitor line tube 19.

Furthermore, since the drip chamber 7 is filled with body fluid and introduced from the side, the body fluid inside is effectively stirred. At the same time,
Since the lower part of the drip chamber 7 is inclined at a predetermined angle, the body fluid flows out smoothly without being retained at the bottom of the chamber, thus improving the fluidity of the body fluid.

(Embodiment) Below, we will explain the case where the embodiment of the present invention is applied to a hemodialysis system. First, in Fig. 1, 1 is a blood circuit, and 2 and 3 are connected to the ends of the blood circuit. Shyant, 4 is blood pump, 5
is a dialyzer, and these are the same as conventional ones.

In the present invention, a double-pipe pressure detector 6 is attached downstream of the dialyzer 5, and a drip chamber 7 is attached to the downstream side thereof.

In the drip chamber 7, as shown in FIG. 2, the chamber body is formed by injection molding so that the opening area of the lower outlet part is increased, and a mesh filter 8 is fixed inside the outlet part, and a mesh filter 8 is fixed to the outside. is the body fluid outlet tube 9 which becomes the blood circuit
is connected.

In addition, in the present invention, the mesh filter 8 also includes:
For example, a bell-shaped or cylindrical injection molded product is preferable.

The upper cap 1 of such a drip chamber 7
On the side of 0, there is a blood inlet 11 connected to the blood circuit.
The degassing line tube 12 is connected to the upper surface of the cap 10.

The drip chamber 7 has a shape in which the lower part of the chamber body is inclined inward at an angle of 10 to 60 degrees with respect to the vertical axis of the filter 8. That is, as shown in FIG. 2 and FIG. 3, which will be described later, the angle α formed by the vertical axis in contact with the outer peripheral surface of the filter 8 and the lower wall surface of the drip chamber is inclined by 10° to 60° toward the body fluid outlet direction. Shape. It is preferable to make this angle as small as possible, but if it is less than 10°, it is virtually impossible to manufacture, and if it is more than 60°, partial retention will likely occur near the body fluid outlet, causing blood coagulation. There are concerns that this will occur.

FIG. 3 shows another embodiment of the drip chamber 7 used in the present invention, in which the blood inlet 11 is provided on the side of the chamber body. It is appropriate that the blood inlet 11 is located at about 1/2 or more of the total longitudinal length of the drip chamber. If the amount is less than this, the blood stirring effect cannot be obtained. Note that it is also possible to connect a drug solution injection line tube 13 to the cap 10 of these drip chambers 7 and inject physiological saline or the like using a syringe or the like.

On the other hand, FIG. 4 shows an example of the double-tube pressure detector 6, in which the inner tube 14 is made of soft plastic.
and a relatively hard plastic outer tube 15. Blood inlet/outlet tubes 16 and 17 forming the circuit 1 are connected to the inner tube 14, and both ends of the outer tube 15 are sealed to form a gap 18 between the inner tube 14 and the outer tube 15. . Further, a pressure monitor line tube 19 is communicated with this cavity 18, and a pressure gauge P is connected to the monitor line tube 19.

Next, an example of the use of the above embodiment will be described. First, blood is guided from the patient's blood vessel through the shunt 2 to the outside of the body by the blood pump 4, and is sent to the dialyzer 5. In the dialyzer 5, after waste substances in the blood are removed through the membrane, the blood is introduced into the drip chamber 7 through the pressure detector 6, and the entire interior is filled with blood from the side entrance.

In the pressure detector 6, the inner tube 14 expands and contracts depending on the pressure within the circuit, and the volume of the cavity 18 changes accordingly. This change is measured by the pressure gauge P via the pressure monitor line tube 19. do.
Furthermore, if air bubbles are present in the drip chamber 7 (such as those remaining in the dialyzer or adhered to the inner surface of the tube), the air bubbles will escape from the degassing line tube 12. In this case, since the degassing line tube 12 is filled with physiological saline in advance (during priming, etc.), there is almost no contact between the blood in the drip chamber 7 and the air. In such a drip chamber 7, after air is removed from the blood and foreign substances are removed by the filter 8, the blood is returned to the patient from the shunt 3.

filling the drip chamber 7 with blood;
A method for filling the degassing line tube 12 with physiological saline is to fill the drip chamber 7 with physiological saline during priming, and by lightly pressing the drip chamber 7, the saline is introduced into the degassing line tube 12. be done. When blood is introduced into the drip chamber 7 in this state, all of the saline in the chamber 7 and a part of the saline in the degassing line tube 12 are replaced with blood. At this time, a predetermined pressure (circuit pressure) is maintained in the drip chamber 7 by the blood pump 4.
is added to the degassing line tube 1.
The physiological saline in the drip chamber 7 will not flow out.

I would like to add here that it has been known in the past that the drip chamber 7 allows blood to flow in from the side, but this is done to prevent blood from directly falling and scattering when an air layer is formed at the top of the chamber. , blood is introduced from the side of the chamber,
It is designed to fall gently along the inner wall of the chamber.

In contrast, the drip chamber 7 according to the present invention has the blood inlet 11 on the side.
Blood is effectively stirred in the drip chamber 7, so that even if air bubbles are mixed in, it immediately flows out to the degassing line tube 12.The method of use is different. .

In addition to hemodialysis systems, the present invention can also be applied to blood circuits for plasma exchange, and can also be applied when body fluids other than blood, such as ascites, are treated by extracorporeal circulation.

(Effects) According to the present invention described above, in an extracorporeal circulation circuit for body fluids, the entire interior of the drip chamber provided in the middle of the circuit can be filled with blood. Blood clots can be prevented without contact. Therefore, anticoagulants can be significantly reduced or eliminated. Furthermore, even if air bubbles should enter the drip chamber, they will escape through the degassing line tube, and the pressure inside the circuit can also be measured using the double tube upstream of the drip chamber. Furthermore, in the present invention, since the degassing line tube is filled with liquid,
The body fluid in the drip chamber does not come into contact with the outside air through this degassing line tube. Therefore, the occurrence of blood clots and contact with germs can be prevented.

Furthermore, in the present invention, since the body fluid flows in from the side of the drip chamber, the body fluid inside the chamber is efficiently agitated, and the occurrence of blood clots due to body fluid retention can be suppressed. Moreover, since the lower part of the drip chamber is formed at a predetermined angle with respect to the vertical axis of the filter, the body fluid in the chamber flows smoothly from the entire circumference of the bottom of the chamber to the outlet tube. The residence time of body fluids becomes extremely short. Therefore, the occurrence of blood coagulation, that is, thrombus, is suppressed, and the injection of anticoagulant becomes unnecessary or reduced. Effects such as this can be obtained.

[Brief explanation of the drawing]

Fig. 1 is an overall schematic diagram showing an embodiment of the present invention, Figs. 2 and 3 are schematic diagrams of a drip chamber used in the present invention, and Fig. 4 is a schematic diagram of a double pipe for pressure detection used in the present invention. 5 are schematic diagrams of a conventional extracorporeal circulation circuit, and FIGS. 6 and 7 are schematic diagrams of a conventional drip chamber. In the figure, 1 is a blood circuit, 5 is a dialyzer, 6 is a pressure detector, 7 is a drip chamber, and 12 is a degassing line tube.

Claims (1)

[Claims for Utility Model Registration] A drip chamber with a filter attached to the bottom and a double-pipe pressure sensor attached to the upstream circuit of the drip chamber, and the drip chamber is filled with body fluid, and the chamber is filled with body fluid. A body fluid extracirculation circuit that uses the body fluid in a drip chamber in a non-contact state with gas by filling a degassing line connected to the upper part with liquid, the body fluid in the drip chamber being connected to the lower part of the body. A circuit for external circulation of body fluid, characterized in that the body is inclined inwardly at an angle of 10° to 60° with respect to the vertical axis of a filter part provided in the drip chamber, and a body fluid inlet is connected to a side of the drip chamber body. .