JP2010069278A - Body fluid purifier which can be embedded in body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To conquer problems accompanying the development of a small body fluid purifier which can be continuously employed for a long time by being embedded in the body or being carried, namely, the problems of: (a) a large amount of dialyzing fluid is needed; (b) the continuous infusion of an anticoagulant agent preventing the coagulation of a circuit is needed; and (c) the membrane life is short since protein, etc. adhere to a filtration film. <P>SOLUTION: Lymph, ascites, or blood plasma is utilized as filtrate, filtration and reabsorption are performed by alternately applying positive pressure and negative pressure to this via the filtration film, an adhesive material is removed, and the filtrate containing much urine toxin matter is obtained and is excreted as self-urine from the urethra. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

Medicine, blood purification

The number of hemodialysis patients continues to increase worldwide, reaching approximately 270,000 in Japan. Many patients go to specialized facilities and receive extracorporeal hemodialysis three times a week. Each dialysis requires 3 to 4 hours, which is a heavy physical, time and economic burden.

The need for an implantable hemodialysis machine has been pointed out for decades. It is expected that it will take several decades in the future to put the most anticipated “renal transplantation by regenerative medicine” into practical use. The present invention has developed a small-sized “implantable body fluid purification device” having a new function of concentrating uremic toxin substances without spending many years by combining existing technologies. It aims to replace some of the functions of hemodialysis. This is expected to reduce the number of dialysis and time required at the facility.

In developing a “small body fluid purification device” that can be implanted in the body and can be used continuously for a long period of time, it is necessary to overcome the following problems. 1. A large amount of dialysate is required. 2. Need continuous infusion of anticoagulant to prevent circuit clotting. 3. Since the protein adheres to the filtration membrane, the membrane life is short.

As a body fluid to be filtered, lymph fluid, ascites, or plasma that does not contain red blood cells is used, and positive pressure and negative pressure (including zero pressure) are alternately applied over time through a filtration membrane to perform filtration and reabsorption. . By this method, the sticky substance is removed and a filtrate containing a large amount of uremic toxin is obtained and excreted from the ureter as self-urine. This method does not require dialysate. In addition, since body fluids that do not contain red blood cells are used, blood clots can be avoided. Adhesives are removed intermittently by the reverse flow generated in the filtration membrane, extending the membrane life.

More particularly, the present invention provides:
(B) Blood filtration or blood filtration dialysis module, that is, “a capsule-shaped container is filled with a hollow fiber membrane type or flat plate type dialysis membrane, and both ends thereof are potted on both ends of the container with a curable resin. Liquid-tightly processed to form open end surfaces at both ends of the container, each open end surface is connected to a cannula for introducing or deriving body fluid, and each capsule-shaped container has a plurality of surfaces constituting the filtrate compartment. This is a body fluid purification device in which a plurality of modules each having an opening are connected in series or in parallel.
(B) In the body fluid purification device according to (a) above, the container surface constituting the filtrate compartments 9 and 10 of the module has one or more openings.
(C) In the body fluid purification device according to (a) above, the connections between the modules are made as follows.
1. “One of the open end faces at the container end of the module” is connected to “one of the open end faces at the container end of another module” by the connection circuit 11.
2. At least one of the openings of “the container surface constituting the filtrate compartment 9 of the module” is “the opening of the container surface constituting the filtrate compartment 10 of another module” and “the circuit 15 having a liquid feed pump”. Connected.
(D) In the body fluid purification device of (a) above, “two or more types of membranes having different solute filtration capabilities” are used as the dialysis membrane.
(E) In the body fluid purification device of (a) above, at least one of the openings provided in the “container surface constituting the filtrate compartments 9 and 10 of the module” is used as the filtrate outlets 18 and 19. That is, it connects with the cannulas 22 and 23 through the valves 20 and 21 or with the cannula having the valves, and guides the filtrate to the urinary tract or the container.

When the pump is driven, the internal pressures of the modules before and after the pump change, one of which is negative and the other is positive. In the negative pressure module, “molecules that can pass through the filtration membrane” are filtered from the body fluid. Conversely, in the positive pressure module, “molecules that can pass through the filtration membrane” are reabsorbed from the filtrate. Part of the filtrate passes through the valve when the internal pressure rises and becomes self-urine, drained, or transferred to another compartment.

Although various selections are possible for the number of modules and the filtration membrane of each module, as an example, an apparatus in which two modules are connected in series will be described. When “Standard filtration membrane 3 suitable for filtration of uremic substances such as urea and creatinine” is arranged in module 1 and “filtration membrane 4 for water removal” is arranged in module 2, “module 1 is shaded. When pressure is applied, water, electrolytes, and uremic substances are filtered from the standard filtration membrane 3. These substances are sent to the module 2 by a pump, because the module 2 is at a positive pressure, and therefore the filtration membrane 4 for water removal. The water and electrolyte that can pass through the water are reabsorbed, and the substance adhering to the dewatering filter membrane 4 is removed by the reabsorption flow at this time. When the internal pressure rises above a certain level, it is discharged from the filtrate outlet 19 together with water and electrolyte.

When the pump is rotated backward after a certain time, the module 2 becomes negative pressure. For this reason, water and electrolyte are filtered and sent to the module 1. Since these can pass through the standard filtration membrane 3, the substance adhering to the membrane is removed by the flow of reabsorption at that time. If the pressure characteristic of the valve 20 provided in the filtrate outlet 18 of the module 1 is adjusted, the amount of water excretion can be adjusted.

In conventional hemodialysis, several liters of water retention occurred in some patients during a non-dialysis period of 2 to 3 days. Suppressing excessive water retention with this device can alleviate the patient's pain of suppressing water intake. Moreover, the fluctuation | variation of a bodily fluid quantity can be restrained little and the burden with respect to a cardiovascular system is reduced. Furthermore, since uremic toxins can be concentrated and excreted, it is possible to reduce the number of facility dialysis and shorten the dialysis time.

Blood purification devices that use two types of hollow fiber filtration membranes include “a plasma separator that separates blood into blood cells and plasma” and an “artificial kidney that adsorbs and removes LDL cholesterol in blood” in combination with a plasma separator. There is. Both are intended for macromolecules and macroparticles and are not intended for removal of uremic substances. Also, the lifetime of the membrane is short, the device is huge, and it is difficult to implant or carry in the body.

Of these, the plasma separator is in common with the present invention in that it uses two types of modules with different filtration characteristics. However, the liquid flow direction is fixed, and the connection between the modules is made between the "open end face at the end of the container" and the "opening of the container face constituting the filtrate compartment" of the other module. In this respect, the mechanism is different from the present invention. The function is mainly “removal of macromolecules such as abnormal antibodies”, which is different from the present invention.

In the “artificial kidney that adsorbs and removes LDL cholesterol and the like in blood”, a method of alternately switching the liquid flow is performed. Although this point is common to the present invention, this artificial kidney is a device for recovering and removing “adsorbed LDL cholesterol and the like”, and does not have a function of concentrating or excreting uremic substances.

An apparatus for removing excess moisture in the body includes an ECUM (extracorporeal ultrafiltration apparatus). This device does not require dialysate, but lacks the function of removing uremic substances because it uses only a filtration membrane for water removal. Also, the device is huge and it is difficult to implant or carry it in the body.

“Hemofiltration dialysis methods” for the removal of water, electrolytes, and uremic substances include “Push and Pull devices”. This device has a function of rotating the water removal pump every few minutes to generate a “filtered flow and reabsorbed flow” in the filtration membrane. It is known that this function suppresses the performance degradation of the film. In this respect, this device is in common with the present invention, but this device was devised to add and remove dialysate from the blood circuit, so the module "opening in the container surface constituting the filtrate compartment" Is connected to the “dialysate bag” via the “circuit having the liquid pump” and not connected to other modules. It is also different from the present invention in that blood is filtered, a large amount of dialysate is required, a plurality of filtration membranes having different performances are not used, a concentration function of uremic substances is not provided, and a device is large. ing.

The technical elements of the present invention have already been prepared as described in [0011] to [0015], and a small-sized “implantable body fluid purification device” having a function of concentrating uremic substances by newly devising the combination. It is thought that early development is possible.

An apparatus in which two modules are connected in series has the following structure.
(1) The standard filtration membrane 3 is arranged in the module 1, and the water removal filtration membrane 4 is arranged in the module 2.
(2) The open end surface 5 at the upper end of the container of the module 1 is connected to a cannula 6 for introducing lymph from the lymphatic vessel. In the case of adults, the production amount of lymph is 2 to 4 liters per day.
(3) The open end surface 7 at the lower end of the container of the module 1 is connected to the open end surface 8 at the upper end of the container of the module 2 by the body fluid circuit 11.
(4) The opening 12 provided on the container surface of the module 1 is connected to the opening 13 on the container surface of the module 2 by a “filtrate circuit 15 having a liquid feed pump 14 capable of rotating in reverse”. A “magnetic levitation motor” used for an artificial heart is used for the liquid feed pump 14. Power is obtained from an external battery.
(5) The open end surface 16 at the lower end of the container of the module 2 is connected to the cannula 17. The lymph is guided into the abdominal cavity via this cannula and taken up again into the lymphatic vessels.
(6) The module 1 and the module 2 have filtrate outlets 18 and 19, respectively, and are connected to cannulas 22 and 23 having valves 20 and 21, respectively. These cannulas connect with the urinary tract.

An example of the bodily fluid purification apparatus of this invention is shown.

Explanation of symbols

1 Module 1
2 Module 2
DESCRIPTION OF SYMBOLS 3 Standard filtration membrane 4 Filtration membrane for dewatering 5 Open end surface of body fluid compartment 6 Body fluid introduction | transduction cannula 7 Open end surface of body fluid compartment 8 Open end surface of body fluid compartment 9 Filtrate compartment 10 Filtrate compartment 11 Body fluid circuit 12 between modules Filtrate compartment The opening 13 of the filtrate compartment 14 The liquid feeding pump 15 The filtrate circuit 16 having the liquid feeding pump The opening end face 17 of the body fluid compartment The cannula 18 leading the body fluid into the abdominal cavity or lymphatic vessel The filtrate outlet 19 The filtrate drainage Outlet 20 Valve 21 Valve 22 Cannula 23 connected to urinary tract Cannula connected to urinary tract

Claims (1)

Blood filtration or blood filtration dialysis module, that is, “the inside of a capsule-shaped container is filled with a hollow fiber membrane type or flat plate type dialysis membrane, and both ends thereof are liquid-tight in a potting manner at both ends of the container with a curable resin. Processed and open end faces at both ends of the container, each open end face is connected to a cannula for introducing or discharging body fluid, and the surface constituting the filtrate compartment of each capsule-like container has a plurality of openings This is a body fluid purification device in which a plurality of modules each having a part are connected in series or in parallel, and includes the following.
(A) At least one of the “cannulas for introducing body fluid” provided on the open end face of the module is a cannula for introducing body fluid not containing red blood cells, that is, lymph fluid, ascites, or plasma.
(B) The modules are connected by a circuit that connects the “open end faces provided at the end of the container”.
(C) There is one or more openings in the “container surface constituting the filtrate compartment” of each module, at least one of which is an opening provided in the “container surface forming the filtrate compartment” of the other module And a “circuit having a liquid feed pump”.
(D) At least one of the openings provided in the “vessel surface forming the filtrate compartment” of the module is a filtrate discharge port.
(E) “Two or more types of membranes having different solute filtration capacities” are used for the dialysis membrane.

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