JPH0652836U - Ultrafiltration device for blood - Google Patents

Abstract

(57) [Summary] [Purpose] In an ultrafiltration device interposed in the extracorporeal circulatory system when monitoring the pathological condition of a patient with a disease in the circulatory system, the filtrate is collected and the blood concentration gradually increases. Even so, the purpose of the present invention is to prevent a burst accident in a weak part such as a connector without lowering the collection efficiency of the filtrate and without increasing the internal pressure of the extracorporeal circulation system. A blood flow path 5 for flowing blood along one surface of the ultrafiltration membrane 2 and a filtrate suction port 6 for sucking out a filtrate of blood that permeates from one surface side to the other surface side of the ultrafiltration membrane 2 are formed. The blood flow path 5 is formed so as to gradually thicken from the upstream side to the downstream side.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an ultrafiltration device for blood, which is inserted into a flow path of an extracorporeal circulation system of blood to collect a filtrate thereof in order to monitor a pathological condition of a patient.

[0002]

[Prior art]

 For example, when monitoring the pathological condition of patients with diseases in the circulatory system, blood is collected, serum is separated, and the components are tested. Since the components contained in are related to each other in terms of concentration, the extracorporeal circulatory system is equipped with an ultrafiltration device to eliminate the troublesome task of collecting blood and separating serum at each test. The filtrate is sampled under 45,000 and the filtrate is automatically measured by a continuous electrolyte concentration measuring device.

An ultrafiltration device for blood used in such a monitor device has a groove-shaped blood flow path for flowing blood on one side through an ultrafiltration membrane and a filtrate for sucking filtrate on the other side. A suction port is formed. The blood flow path is formed in a spiral shape, and the filtrate suction port is also formed in a spiral groove along the blood flow path to lengthen the total length of the blood flow path and contact the filtration membrane. Area is widened and the recovery efficiency of the filtrate is improved.

[0004]

[Problems to be solved by the device]

 However, when the filtrate is collected from the blood while flowing through the spiral blood channel, the concentration of blood gradually increases, and polymer substances such as fibrin and proteins adhere to the surface of the blood channel and the filtration membrane. As a result, not only is the collection efficiency of the filtrate reduced, but a vicious cycle in which blood becomes difficult to flow and adherents grow further, and thrombi are easily formed, and further, the pressure inside the extracorporeal circulation system rises, In the worst case, there was a problem that weak parts such as connectors burst and a blood leak accident occurred.

Further, if the filtrate suction port is formed in a spiral groove, it takes time for the filtered filtrate to be sucked out through the groove, so that a time lag is observed when monitoring a pathological condition. Not only does this occur, but the efficiency with which the filtrates that have been filtered at the same time are collected at the same time is poor, and the filtrate used as the monitor data contains a mixture of various filtrates at different times. There was a problem that it was unclear whether the condition at the time was being monitored.

Further, conventionally, the blood flow path is formed in a spiral shape to extend the total length of the blood flow path, but it is desired to further improve the recovery efficiency and downsize the filtration device. Therefore, the present invention firstly improves the recovery efficiency by making fibrin or the like less likely to adhere to the blood flow path, and second, it is possible to simultaneously recover the filtered filtrate at the same time. In addition, it is a technical issue to improve the collection efficiency by increasing the total length of the blood flow path.

[0007]

[Means for Solving the Problems]

 In order to solve this problem, the first invention of the present application is to absorb a blood flow path for flowing blood along one side of the ultrafiltration membrane and a filtrate of blood that permeates from one side to the other side of the ultrafiltration membrane. A filtrate suction port to be discharged is formed, and the blood flow path is formed so as to gradually become thicker from the upstream side to the downstream side. The second invention of the present application is characterized in that a porous material is additionally provided on the filtrate inlet side of the ultrafiltration membrane. Further, in the third invention of the present application, the filtrate suction port is formed along the outer peripheral surface of the filtrate collection block formed in a three-dimensional shape with a substantially circular outer periphery, and the blood flow path sandwiches the ultrafiltration membrane. It is characterized in that it is formed along the inner peripheral surface of the blood flow block which is superposed on the outside of the filtrate collection block.

[0008]

[Action]

 According to the first invention of the present application, since the blood flow passage is formed so that the cross-sectional area becomes larger toward the blood outlet where the blood concentration is higher, the abrupt pressure of the pipe is increased without causing blood retention. Blood can be evenly flowed by preventing such rise, and at the same time, fibrin, etc. does not easily adhere to the surface of the blood flow path or the filtration membrane, and even if it adheres, it will be easily washed away by the bloodstream, so that adhered matter Hard to grow. Further, according to the second invention of the present application, since the filtrate permeates the porous material and is collected at the filtrate suction port, it is possible to simultaneously collect the filtered filtrate. In this case, since the ultrafiltration membrane is in contact with the surface of the porous material, the pressure difference between the blood flow path and the filtrate suction port side can be increased, and the recovery efficiency can be further enhanced. Further, according to the third invention of the present application, since the blood channel and the filtrate suction port are three-dimensionally formed, the total length of the channel can be made longer and the recovery efficiency is improved.

[0009]

【Example】

 Hereinafter, the present invention will be specifically described with reference to the embodiments shown in the drawings. FIG. 1 is a sectional view showing an example of an ultrafiltration device for blood according to the present invention.

In the figure, reference numeral 1 denotes an ultrafiltration device for blood in which a blood flow block 3 and a filtrate collection block 4 are arranged with an ultrafiltration membrane 2 interposed therebetween. A blood channel 5 in the form of a groove is formed on the side of the blood flow block 3, and a filtrate suction port 6 for sucking the filtrate through the ultrafiltration membrane 2 is formed on the side of the filtrate collection block 4. As the ultrafiltration membrane 2, for example, a membrane capable of collecting a filtrate having a molecular weight of 45,000 or less is used.

The blood flow path 5 is spirally engraved on the surface of the blood flow block 3 to form a blood inlet 5 A at the inner end of the spiral and a blood outlet at the outer end of the spiral. 5B is formed. For example, blood drawn out from the living body is allowed to flow into the blood inlet 5A, flow out from the blood outlet 5B, and be returned to the living body again via an extracorporeal circulation device (not shown). Is made in. Further, the blood flow path 5 is formed so that the cross-sectional area gradually increases from the blood inlet 5A to the blood outlet 5B. In this example, the width of the concave groove is fixed for convenience of processing. The depth of the groove is gradually increased, but the depth of the groove may be made constant and the width thereof may be gradually increased, that is, the cross-sectional area may be gradually increased.

A porous material 7 is additionally provided on the filtrate inlet 6 side of the ultrafiltration membrane 2, and the filtrate inlet 6 is made of a porous material so that the filtrate passing through the porous material 7 can be collected in a concentrated manner. It is formed on the back side of the material 7. The porous material 7 is made by bundling and bonding the follow fibers such as the potting portion of the artificial kidney so that the filtrate flows linearly in the thickness direction of the porous material 7, and further cut into a predetermined thickness. Is formed.

Therefore, regardless of where in the blood channel 5 from the inflow port 5A to the outflow port 5B is filtered, the filtrate linearly flows toward the filtrate suction port 6, and at the same time, the filtered liquid is filtered. Can be collected at once and promptly. A suction pump (not shown) that connects the suction port 6 to a negative pressure is connected to the filtrate suction port 6, and an electrolyte concentration continuous measuring device (not shown) that automatically analyzes the collected filtrate. Are connected.

The above is an example of the configuration of the present invention, and its operation will be described below. First, when the blood inflow port 5A and the blood outflow port 5B are connected to the blood circuit of the extracorporeal circulation system to activate the extracorporeal circulation device, the blood flowing out of the living body passes through the blood flow path 5 of the blood ultrafiltration device 1. And is returned to the body again. At this time, when the suction pump connected to the filtrate suction port 6 of the ultrafiltration device 1 is started, the pressure inside the filtrate suction port 6 becomes lower than that of the blood flow path 5, so the ultrafiltration membrane 2 The blood flowing in the blood flow path 5 is filtered while coming into contact with, and the filtrate permeates the porous material 7 and is collected in the filtrate suction port 6. Even if the pressure difference between the filtrate suction port 6 and the blood channel 5 is increased, the porous material 7 is pressed against the entire surface of the filtration membrane 2, so that, for example, when a groove-shaped filtrate suction port is formed. As in the case of the above, the filtration membrane 2 is not sucked into the filtrate suction port and is not broken, and the recovery efficiency can be improved.

Then, the filtrate can flow straight through the porous material 7 regardless of which part of the blood flow path 5 is filtered, and can be concentrated and collected at the filtrate suction port 6. There is almost no time lag. Further, the filtrate suction port 6 need only be formed on the back surface side of the porous material 7, and it is not necessary to form the filtrate suction port 6 facing the blood flow path 5 with high precision, which simplifies the processing and reduces the manufacturing cost. It can be reduced.

Further, since the concentration of blood gradually increases as the filtrate is extracted, it becomes difficult to flow in the blood flow path 5, but the blood flow path 5 gradually becomes thicker from the upstream side to the downstream side. Since it is formed so that the blood flow will not be stagnant and the pressure inside the tube will not partially rise due to the increase in concentration. Therefore, fibrin or protein is unlikely to adhere to the surface of the blood flow path 5, and even if adhered, the blood flow is not stopped and is easily washed away by the blood, so that the adhered matter does not easily grow.

2 and 3 are cross-sectional views showing another ultrafiltration device for blood according to the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals and detailed description thereof will be omitted. In this example, the filtrate suction port 6 is formed along the outer peripheral surface of the filtrate collection block 10 formed in a three-dimensional shape with a substantially circular outer periphery, and the blood channel 5 sandwiches the ultrafiltration membrane 2. Therefore, it is formed along the inner peripheral surface of the blood flow block 8 which is superposed on the outside of the filtrate collection block 10. The filtrate collection block 10 is formed, for example, in a hemispherical shape (see FIG. 2), a conical shape (see FIG. 3), a columnar shape (not shown), and the blood flow block 8 has a spherical shell shape overlapping the hemisphere. (See FIG. 2), tapered sleeve shape overlapping the cone (see FIG. 3), and cylindrical shape overlapping the cylinder (not shown).

The blood flow path 5 is formed in a spiral shape from above the blood flow block 8 downward, and a blood inlet 5 A is formed at an upper end portion thereof, and a blood flow path is provided at a lower end portion thereof. An outlet 5B is formed. That is, since the blood flow path 5 is formed so that the blood flows from the upper side to the lower side, it is possible to facilitate the flow of the blood by applying gravity to prevent the blood from staying.

Further, the filtrate suction port 9 is directly connected to the filtrate outlet 11 via the conduit 12, and is filtered at any part between the inlet 5A and the outlet 5B of the blood channel 5. In addition, the filtrate that has been filtered at the same time is concentrated in the filtrate outlet 11 and can be collected at substantially the same time.

Since the blood channel 5 and the filtrate suction port 9 are three-dimensionally formed in this manner, the total length of the blood channel 5 can be increased even if the bottom area of the filtration device 1 is reduced. It is possible to improve the collection efficiency. In this example, the cross-sectional area of the blood flow path 5 may be gradually increased from the blood inlet 5A toward the blood outlet 5B, and the porous material may be provided on the filtrate inlet 9 side of the ultrafiltration membrane 2. May be attached.

[0021]

[Effect of device]

 As described above, according to the present invention, the blood flow path gradually becomes thicker from the upstream side to the downstream side, so that blood flow can be secured even if the blood concentration increases as it goes downstream. Therefore, there is an effect that fibrin or protein can be prevented from adhering or growing in the blood channel to improve recovery efficiency. In addition, since a porous material is placed on the filtrate suction side of the ultrafiltration membrane, the filtered filtrate can be quickly recovered at the same time regardless of which part of the blood flow path is filtered, and the time lag for collecting the filtrate can be reduced. It has the effect that it can be resolved. Furthermore, since the blood flow path and the filtrate suction port are formed three-dimensionally, even if the bottom area is narrow, the total length of the flow path can be lengthened and the recovery efficiency can be further improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of an ultrafiltration device for blood according to the present invention.

FIG. 2 is a cross-sectional view showing another ultrafiltration device for blood according to the present invention.

FIG. 3 is a cross-sectional view showing another embodiment.

[Explanation of symbols]

1 ... Ultrafiltration device for blood 2 ... Filtration membrane 3 ... Blood flow block 4 ... Filtrate collection block 5 ... Blood flow channel 5A ... Blood inlet 5B ... Blood outlet 6 ... filtrate suction port 7 ... porous material 8 ... blood flow block 9 ... filtrate suction port 10 ... filtrate collection block

Claims (3)

[Scope of utility model registration request] 1. A blood flow path (5) for flowing blood along one surface of an ultrafiltration membrane (2) and sucking out a filtrate of blood that permeates from one surface side to the other surface side of the ultrafiltration membrane (2). An ultrafiltration device for blood, characterized in that a filtrate suction port (6) is formed, and the blood channel (5) is formed so as to gradually become thicker from the upstream side to the downstream side. 2. A spiral blood flow channel (5) for flowing blood along one surface of the ultrafiltration membrane (2), and a blood flow channel (5) for permeating from one surface side to the other surface side of the ultrafiltration membrane (2). For blood, characterized in that a filtrate suction port (6) for sucking the filtrate is formed, and a porous material (7) is additionally provided on the filtrate suction port (6) side of the ultrafiltration membrane (2). Ultrafiltration device. 3. A blood channel (5) for flowing blood along one surface of the ultrafiltration membrane (2) and a filtrate of blood that permeates from one surface side of the ultrafiltration membrane (2) to the other surface side. A filtrate suction port (9) is formed, the filtrate suction port (9) is formed along the outer peripheral surface of the filtrate collection block (10) formed in a three-dimensional shape with a substantially circular outer periphery, and the blood flow path is formed. (5)
Is formed along the inner peripheral surface of the blood flow block (8) which is superposed on the outside of the filtrate collection block (10) with the ultrafiltration membrane (2) interposed therebetween. apparatus.