JPS60246762A - Drip chamber for external recirculation circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement of a drip chamber of a blood circuit used in extracorporeal circulation type artificial dialysis, plasma exchange, etc.

(Prior art and its problems) For blood circuits for extracorporeal circulation such as artificial dialysis and plasma exchange, a drip filter with a filter is used to remove air bubbles and monitor pressure, and to prevent clots such as blood clots from entering the body. chamber is used.

Figure 5 shows the most commonly used model, with an inner diameter of 2
A bag-shaped filter 2 made of synthetic fiber such as polyester or nylon is attached to the lower end of the outer cylinder part 1 made of 0 mm polyvinyl chloride.
and a core tube 3 which is inserted into the bag-shaped filter 2 and has a notch 4 on the side surface, and is welded with a high frequency welder.
A trap cap 8 equipped with a fluid inlet 6 and a pressure monitoring monitor and a drug injection line 7 is glued to the upper part.

There is usually one cutout 4 in the core tube 3, and in rare cases there are two, and the fluid in the drip chamber flows mostly downward from the cutout 4, and a small amount flows out from the upper opening. FIG. 6 (one notch) and FIG. 7 (two notches) conceptually illustrate this fluid flow state at the AA cross section in FIG. 5.

When there is only one notch shown in FIG. 6, the fluid moves only in the portion facing the front of the notch, but the state of fluid movement in the opposite side of the notch and in the vicinity of the Welgoo welded portion 5 is extremely poor.

Furthermore, when there are two notches in FIG. 7, the fluid movement is better than when there is only one notch, but the flow is only good near the notches.

In addition, FIG. 8 and FIG. 9 are schematic diagrams showing the state of the fluid flowing into the core tube. FIG. 8 shows the case where there is one notch, and FIG. 9 shows the case where there are two notches. It shows.

In such a drip chamber, when blood is used as the fluid, thrombus formation is sometimes observed near the high frequency welder adhesive surface 5 and the upper part of the core tube 3. The cause of this thrombus is that (
It is thought that a) contact between air and blood and (b) partial retention of blood are caused as a synergistic effect with the patient's own blood function defect.

Among these, the air in (a) may be attached in the form of air bubbles from the artificial kidney body, or may be insufficiently degassed before clinical use.
It adheres to and remains on the filter 2 in the drip chamber. These air bubbles are usually removed by applying an impact such as hitting the outer cylinder part 1 of the drip chamber from the outside, or by coating the surface of the filter 2 with a polymer having a hydrophilic group to prevent the air bubbles from adhering. Countermeasures are being attempted.

It is also believed that the partial retention in (b) above causes air bubbles to easily remain in the area where the fluid accumulates, or that thrombus occurs due to the retention itself. In the conventional drip chamber described above, as a result of observing the state of movement of the internal fluid, and judging comprehensively from the clinical usage situation, it seems that this partial stagnation is the main cause of thrombus occurrence.

For this reason, cylindrical filters as shown in FIGS. 1θ and 11 have recently become known. That is, these are composed of a ring part 10 serving as a base and a mesh part 11, and in FIG.
In Figure 1, the top surface is open.

Since such a filter has a larger actual opening area than the filter section shown in FIG. 5, blood can flow more easily and blood stagnation and thrombus formation are reduced.

However, in such a fill lance, when the mesh part 11 is welded to the ring part fO, the support member 12 that supports the mesh part 11 is required to maintain strength, which increases the opening area. Also, the support member 12
There are problems in that blood turbulence occurs in the vicinity, blood coagulation occurs at the boundary between the support member 12 and the mesh portion 11, and manufacturing is also troublesome.

(Means for Solving the Problems) The present invention was proposed to solve these conventional disadvantages, and in particular, the lower part of the outer cylindrical part of the drip chamber is connected vertically to the outer circumferential surface of the filter part. The filter part is inclined inward from 10° to 60' with respect to the axis, and the filter part is composed of a ring part and a mesh part, and the ring part and the mesh part are injection molded without providing a support member on the mesh part. Its basic feature is that it is integrally molded.

(Example) Examples of the present invention will be described below with reference to the attached drawings from Figure 1 onwards. First, Figure 1 is a conceptual diagram showing an example of a drip chamber according to the present invention, and 20 in the figure is a material such as vinyl chloride. The outer cylinder part 2°l made of synthetic resin is a trap cap fitted onto the upper part of the outer cylinder part 20.

A bubble removal line 22 is connected to the trap cap 21, and a body fluid inlet 23 extending laterally is provided on the side of the cap. . In the present invention, these two
There is no denying that the body fluid inlet 23 is provided at the upper part of the trap cap 21.

Further, a filter portion 2 is provided at the inner lower end of the outer cylinder portion 20.
4, and a body fluid outflow tube 27 is connected to the lower part of this filter part.

FIGS. 2 and 3 are detailed views of the filter section 24. FIG. First, FIG. 2 shows a ring part 25 provided with a bell-shaped mesh part 26, which are integrally molded by injection molding. Since the bell-shaped mesh portion 26 is mechanically strong and does not easily deform, the conventional support member 12 is not required. Furthermore, since there is no corner, turbulent flow of blood around the corner and blood clotting at the corner can be prevented.

However, as long as a predetermined strength is maintained, the third
As shown in the figure, the mesh portion 26 may have a cylindrical shape.

In this way, the mesh part 26 in the present invention is simply composed of the ring part 25 and the mesh part 26, and the mesh part 26 is simply composed of the ring part 25 and the mesh part 26.
One of the features is that no support member of No. 6 is provided.

In the mesh part 24, the ring part 25 is fixed to the bottom of the outer cylinder part 20 by means such as adhesion or welding, and the body fluid outflow tube 27 is inserted and fixed into the ring part 25. In the invention, the angle of inclination of the outer cylinder portion 20.

That is, the angle (α) formed by the vertical axis 30 in contact with the outer circumferential surface of the ring portion 25 of the filter portion 24 and the lower wall surface of the outer cylinder portion 20 is limited to lθ″ to 60″. In other words, it is preferable to make the angle ((X) as small as possible, but it is virtually impossible to manufacture if it is less than 10°, and if it is more than 60", the above-mentioned partial retention of fluid may occur. There is a risk that blood clots may occur.

FIG. 4 shows an example of an extracorporeal circulation circuit incorporating a drip chamber according to the present invention.

In the figure, 40 is a shunt joint that introduces blood from the patient into the circuit, 41 is a rolling pump that supplies blood, and 42
4 is a dialyzer for purifying blood, 43 is a drip chamber according to the present invention, and 44 is a blood return shunt joint.

In the present invention, when the body fluid inlet 23 is provided in the horizontal direction, the entire chamber is filled with body fluid, so pressure monitoring is performed at the pressure detection section 45 provided upstream of the drip chamber 43. This pressure detection section 45 may be any known means. For example, by making the inner cylinder through which body fluids pass through a flexible synthetic resin and the outer cylinder a hard synthetic resin in a double-pipe configuration, pressure changes in the space between the inner cylinder and the outer cylinder can be reduced. It may also be detected.

(Effects of the Invention) As explained above, according to the present invention, in particular, the lower part of the outer cylindrical part is 10 with respect to the vertical axis in contact with the outer circumferential surface of the filter part.
It is tilted inward by 60', and the filter part is composed of a ring part and a mesh part, and the ring part and the mesh part are integrally molded by injection molding without providing a support member on the mesh part. The body fluid that has entered the drip chamber flows out from the entire circumferential direction of the lower part of the outer cylinder part 20 to the outflow tube 27, the residence time of the body fluid becomes extremely short, and the occurrence of blood coagulation, that is, thrombus, is suppressed.
Injection of anticoagulants may be unnecessary or reduced. Therefore, the present invention can be applied to anticoagulant-free dialysis and other extracorporeal circulation therapies.

The inside of the lip chamber can be completely filled with body fluids, and there is no need to create an air layer at the top of the chamber as in conventional lip chambers.Moreover, the inflowing body fluids collide with the opposite side wall and disperse, creating a so-called diffusion effect. , these additive effects can further suppress the occurrence of thrombus.

Furthermore, according to the present invention, since no supporting member is provided in the mesh part, blood coagulation does not occur at the boundary with the mesh part, and furthermore, since it is integrally molded by injection molding, it is easy to manufacture. It provides excellent effects.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram of a drip chamber according to the present invention, FIGS. 2 and 3 are perspective views of a filter section according to the present invention, and FIG. 4 is a circuit diagram of an extracorporeal circulation circuit to which the drip chamber according to the present invention is applied. , FIG. 5 is a conceptual diagram of a conventional drip chamber, and FIGS. 6 and 7 are sectional views taken along line A-A in FIG. In the case of two locations, FIGS. 8 and 9 are side views of the conventional core tube, respectively, and FIGS. 1θ and 11 are perspective views of the conventional filter section. 1,49.2att＊＊＊x
o, 24. . The filter section includes a ring section 25, a mesh unit section 26, and a vertical axis 30. Applicant Yosumi Chemical Industry Co., Ltd. Agent Patent Attorney Shigemi Nishino

Claims (4)

[Claims] (1) A drip chamber provided in the middle of a circuit for extracorporeal circulation of body fluids, comprising an outer cylinder part and a filter part provided at the lower end of the outer cylinder part, and the lower part of the outer cylinder part is connected to the filter part. The filter part is inclined inward by 100 to 60 degrees with respect to the vertical axis in contact with the outer peripheral surface of the filter part, and the filter part is composed of a ring part and a mesh part,
A drip chamber for an extracorporeal circulation circuit, characterized in that the ring part and the mesh part are integrally molded by injection molding without providing a support member on the mesh part. (2) A drip chamber provided in the middle of a circuit for extracorporeal circulation of body fluids, which is composed of an outer cylindrical part and a filter part provided at the lower part of the outer cylindrical part, and the lower part of the outer cylindrical part is connected to the outer peripheral surface of the filter part. lO with respect to the tangent vertical axis
The outer cylinder part is inclined inward by 60° and a body fluid inlet is provided in the upper part of the outer cylinder part in the lateral direction, and the filter part is composed of a ring part and a mesh part, and the mesh part is provided with a support member. A drip chamber for an extracorporeal circulation circuit, characterized in that the ring part and the mesh part are integrally molded by injection molding without providing any. (3) The invention according to item 1 or 2 above, wherein the mesh portion of the filter portion is bell-shaped. (4) The invention according to item 1 or 2, wherein the mesh portion of the filter portion is cylindrical.