JPH041948Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a pressure detector with a filter that is used by being incorporated into a circuit for extracorporeal circulation of body fluids such as hemodialysis and plasma exchange.

(Prior art and its problems) In hemodialysis, plasma exchange, etc., a circuit for extracorporeal circulation of blood is used.

FIG. 9 shows an example of a circuit used in reduced heparin dialysis, in which blood from a patient is flowed from the lower side of the dialyzer 21 to the upper side by a blood pump 20, and the purified blood is passed through a pressure detector. 22, filtered and air bubbles removed in a drip chamber 23,
It has been returned to the patient.

The pressure detector 22, as shown in FIG. It is designed to be connected to a pressure gauge for measurement. Further, the drip chamber 23 has a filter 2 inside the outer cylinder 27.
8, the blood is temporarily stored in the chamber, air bubbles are removed from the blood, and at the same time foreign substances in the blood are removed by a filter 28.

In this way, in the past, the pressure detector and filter part were constructed as separate and independent members, so
This increases the number of parts used and the manufacturing process, which is disadvantageous in terms of manufacturing efficiency and cost. In addition, because blood is stored in two places, the pressure detector and the drip chamber, the amount of blood circulating outside the body increases, and at the same time, there are many opportunities for the blood to come into contact with air, etc., leading to problems such as blood clots and contamination. There was a problem that this was likely to occur.

The present invention was proposed as a result of studies to solve the above-mentioned problems.

(Means for Solving the Problems) As shown in FIG. 1 corresponding to the embodiment, the present invention is a pressure detector that is installed in the middle of an extracorporeal fluid circulation circuit and simultaneously performs filtration of body fluids. Consisting of a flexible outer tube 1 and a flexible inner tube 2, a bell-shaped filter 3 is attached to the inner tube 2, and body fluid guiding tubes 4, 5 are installed at both ends of the outer tube 1. is connected to the outer tube 1, and a pressure monitor line 7 is connected to the outer tube 1, which communicates with the space 8 between the inner tube and the outer tube.
A deaeration line 6 communicating with the inner tube 2 is connected to the inner tube 2, and both ends of the outer tube and the inner tube are fixed by welding.

(Function) Body fluid flows into the flexible inner tube 2 from one body fluid guide tube 4 and is temporarily stored therein. meanwhile,
The air in the body fluid can be vented to the outside through the degassing line 6. Moreover, when the pressure in the circuit increases, the inner tube 2 expands, and the space 8 between the inner tube 2 and the outer tube 1
The air pressure in the space 8 increases, and conversely, when the pressure decreases, the air pressure in the space 8 decreases. That is, the pressure change in the space 8 is measured with a pressure gauge through the pressure monitor line 7, and the pressure inside the circuit is detected.

Furthermore, the body fluid is transferred from the body fluid guide tube 4 to the inner tube 3.
When the fluid enters the body, a filter 3 removes foreign substances from the body fluid.

(Embodiment) An embodiment of the present invention will be described below with reference to the accompanying drawings. First, in FIG. 1, FIG. 1A, and FIG. 1B, 1 is an outer tube, which is made of relatively thick or hard plastic For example, it is made of vinyl chloride (vinyl chloride, etc.). Moreover, 2 is an inner tube inserted into this outer tube, and is made of flexible plastic such as soft vinyl chloride.

A bell-shaped filter 3 is attached to the body fluid introduction side end of the inner tube 2, and a body fluid introduction tube 4 communicating with the inside of the filter 3 is connected to one end of the outer tube 1. A body fluid outlet tube 5 communicating with the inner tube 2 is connected to the other end. Further, a degassing line tube 6 communicating with the inside of the inner tube 2 is connected to one end of the outer tube 1, and a pressure monitoring line communicating with the space 8 between the outer tube 1 and the inner tube 2 is connected to the other end. Tube 7 is connected.

In addition, when the filter 3 is made of synthetic fiber such as polyester or nylon, the size of the filter 3 is preferably <2R, as shown in FIG. 2.

R: Converted diameter of the flexible inner tube: Length of the filter The reason for this is that if R is long, the filter mesh will tend to stick to the inner surface of the inner tube 2, which will cause the formation of blood clots. .

The filter 3 is more preferably made of an injection molded product of synthetic resin because it has higher elasticity.

FIG. 3 shows a method of manufacturing the pressure detector shown in FIG. 1. First, insert the inner tube 2 into the outer tube 1, attach the filter 3 to one end of the inner tube 2, insert the body fluid introduction tube 4 into the filter 3, and connect the outer tube 1 and the inner tube 2. A pressure monitor line tube 7 is inserted between them.

Note that a core pin (not shown) is inserted into each of the tubes 4 and 7.

In this arrangement, one end of the outer tube 1 is clamped with a mold, and each member is welded using a high frequency welder.

Next, insert the body fluid outlet tube 5 and the degassing line tube 6 into the other end of the inner tube 2 (insert the core pin as described above), and clamp the other end of the outer tube 1 with a mold. Each member is then welded using a high-frequency welder.

4 to 6 show other embodiments of the present invention.

FIG. 4 shows a filter 3 in the middle part of the inner tube 2.
It has been established. The manufacturing method is to first weld the filter 3 to the inner tube 2 using a high frequency welder, and then weld the inner tube 2 together with the outer tube 1 using a high frequency welder.

FIG. 5 shows that the inner tube 2 is extended to the middle of the outer tube 1, the filter 3 is inserted into the lower end of the inner tube 2, and the lower end of the inner tube 2 is inserted into the outer tube together with the filter 3. It is welded to the inside of 1 using a high frequency welder. In this embodiment, the body fluid inlet tube 4 communicates with the inside of the outer tube 1, and the body fluid outlet tube 5 communicates with the inside of the inner tube 2. Further, the degassing line tube 6 communicates with the inner tube 2, and the pressure monitoring line tube 7 communicates with the space 8 between the outer tube 1 and the inner tube 2.

Furthermore, FIG. 6A shows another embodiment of the present invention, in which a lower outer tube 1a is separately molded, a molded filter 3 is attached to the lower outer tube 1a, and the lower outer tube 1a is The upper end is fixed to the lower end of the outer tube 1 together with the inner tube 2 by welding or gluing. Further, in FIG. 6B, the pressure monitor line tube 7 is provided on the side surface of the outer tube 1, and the other configurations are the same as in FIG. 6A.

7 and 8 show a method of using the present invention, in which the blood is pushed from the upper side of the hemodialyzer 10 to the lower side with the blood pump 11. The blood purified by the dialyzer 10 fills the pressure detector 12 of the present invention. This pressure detector 12 corresponds to the embodiment shown in FIG. 1 described above, and the degassing line 6 is attached to the blood introduction side, and the pressure monitor line 7 is attached to the blood outlet side.

Blood leaving the hemodialyzer 10 passes through the inner tube 2 of the pressure detector 12, and at this time, foreign substances in the blood are filtered out by a filter. In addition, the inner tube 2 is filled with blood, and air bubbles in the blood float to the surface and escape from the degassing line 6. Further, when the pressure of the blood in the inner tube 2 changes due to, for example, abnormal operation of the blood pump 11, the flexible inner tube 2 expands or contracts, and the air pressure in the space 8 between the outer tube 1 and the inner tube 2 increases. Change. Changes in the air pressure in the space 8 are detected by a pressure monitor line 7, and the pressure in the entire blood circulation circuit is monitored.

In the case of the embodiment shown in FIG. 5 and FIGS. 6A and 6B, the inside of the inner tube 2 and one end (lower end in the drawing) of the outer tube 1 are filled with blood. As described above, air bubbles in the blood are degassed through the deaeration line 6 of the inner tube 2, and pressure changes in the space 8 are detected by the pressure monitor line 7.

Further, FIG. 8 shows an example of use in reduced heparin dialysis, in which blood is flowed from the lower side of the dialyzer 10 to the upper side. In this case, the degassing line 6 is connected to the pressure detector 12
Attached to the blood outlet side of the

(Effects of the invention) According to the invention described above, since a filter is provided in a conventional pressure detector to provide a filtration function, filtration and pressure detection can be performed simultaneously at one location in the extracorporeal circulation circuit. . Therefore, the amount of body fluid circulating extracorporeally can be reduced by an amount commensurate with the amount within the conventional drip yambar portion, and the chances of the body fluid being activated outside the body are reduced. Further, since the inner tube is filled with body fluid and the body fluid does not come into contact with the pressure detection space, it is possible to prevent the occurrence of blood clots and the like. Moreover, air bubbles in the body fluid can be removed through the degassing line leading to the inner tube. moreover,
The number of parts used is reduced, and the product can be manufactured simply by welding using a high-frequency welder, resulting in a significant reduction in the number of manufacturing steps.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of the present invention.
Figure A is a sectional view taken along line A-A in Figure 1, Figure 1B is a cross-sectional view taken along line B-B, Figure 2 is an explanatory diagram of the filter of the present invention, and Figure 3 is an illustration of an example of the manufacturing method of the present invention. Schematic diagrams for Figure 4, Figure 5 and Figure 6A,
FIG. 6B is a schematic diagram showing another embodiment of the present invention, FIGS. 7 and 8 are schematic diagrams of a dialysis circuit to which the present invention is applied, FIG. 9 is a schematic diagram of a conventional dialysis circuit, and FIG.
The figure is a schematic diagram of a conventional pressure detector and drip chamber. In the figure, 1 is a non-flexible outer tube, 2 is a flexible inner tube, and 3 is a non-flexible outer tube.
4 is a filter, 4 is a blood inlet tube, 5 is a blood outlet tube, 6 is a degassing line tube, 7 is a pressure monitor line tube, and 8 is a space.

Claims (1)

[Scope of Claim for Utility Model Registration] A pressure detector that is installed in the middle of a body fluid extracirculation circuit and that simultaneously filters body fluid, which has a space between an inflexible sealed outer tube and the outer tube. a flexible inner tube that is inserted so as to have a flexible inner tube, body fluid guide tubes are connected to both ends of the outer tube, and at least one body fluid guide tube is communicated with the flexible inner tube; Pressure detection for an extracorporeal fluid circulation circuit, characterized in that a pressure monitor line communicating with the space and a deaeration line communicating with the inner tube are connected, and a filter is installed inside the inner tube or the outer tube. vessel.