IL26988A - Artificial kidney - Google Patents

Description

C O H E N Z E D E K S P I S B A C E PA TEN T A TT O R N EYS LEVONTIN 1169 P A T E N T S D E S I G N S O R D I N A N C E SPECIFICATION ARTIFICIAL KIDNEY JOSEF a German of HEREBY DECLARE fhe nature of this invention and in what manner the same is to be performed to be particularly described and ascertained in and by the following new invention relates to improvements in an artificial An artificial dialysis apparatus through which blood is circulates and in which the blood is subjected dialysis against a wash solution outside the living As dialysis cellulose or cellulose acetate usually is either i film form or in tubing Dialysis of this a sufficiently dialysis the thickness the blood layer must be slight since on the one the dialysis process only the layers of immediately adjacent to the membrane are effective on the other the user then can dispense with prior filling the apparatus with lood which must then be removed and presence introduces certain dangers and The fact that a very thin layer of blood is necessarily used results in an undesirably high to flow of the so that high flow pressures are necessary requiring a blood in turn results in traumatizing the with destruction of blood In the case of f lm this disadvantage is compensated for by arranging small dialysis chambers in in order to diminish Apart from the problems of leak and of blood supplys and the therefore frequently difficult assembl apparatus of the known type usually can be sterilised only Clinicall are given according to the example of of Inouye and a length of cellophane tubing together with a plastic or with a tie band of transversely running cylindrical rods ia wound with a epool araund a The wash solution then flows transversely to the cellophane which is coiled in a horizontal plane and flattened by the tie Since resistance to flow of the blood is intolerably spacer strips are interposed above and the cellophane tubing to enable the tubing to unfold u the thickness of the spacer which thus termine the thickness of the blood laye In order to further diminish blood flow and teach to coil a second cellophane connected in in a second with a wider tie The wash solution then first flow transversely past one thereby coming partially depleted in washing ability by the time it reaches the second Parallel connections of tional tubings according to the above principle will thus reduce the efficiency all the more because the greater the number of tubings connected in tiers one above the the more the wash solution is depleted in passing each or tier of present invention is advantageous for coming problems described According to the present an artificial kidney is provided having a pair of permeable membrane sections with a pair of adjacent inner faces and adapted for exchanging material between a first fluid in a path between said inner faces and a second fluid disposed in engagement the outer faces of said membranes the improvement characterized as a support for such membrane sections a first set of parallel strands supporting tinuously along their lengths the outer surface of one of said membrane and a second set of parallel strands supporting tinuously along their lengths the outer sur ace of the other of said membrane sections and disposed at an angle to said first set of said strands arranged to form two sets of flow channels disposed at an angle relative one another in said membrane sections under pressure of a first permeable membrane section Each tubin in the form of a flattened cylinder and substantially in its flattened form known in the artificial kidney In ai ferred embodiment of the invention the inlet end of each membrane section passed through an opening in the wall of the core Δ sufficient of openings are provided to acommodate the number the openings are distributed at substantially distances from adjacent openings around the periphery of According to the it is further permeable membrane section to pull the end of the dialysis olded over a highly elastic terminal together with the latter under strong so as to be a conical bore a confining or On the wrapping membrane sections essential novelty of the improved kidney thus consists i coiling or any desired sections of pieces of dialysis membrane two or any desired number of tie bands on a common i a in manner of a means this novel arrangement of inlets and outlets of the membranes flora through the assembly is and as will more fully fresh wash solution may reach each Also because of the lengths the multiple membranes of present artificial oompared to a single wrapped or wapped dual membrane of the prior the dialysis effect is greatly The tie bands consist of any inert in the form of netti or braidings addition of spacer As support there also be employed certain suitable which may be fabricated of plastics or other materials which are inert in the presence of the washing solution and with or without spacer threads In practice of the it is preferred to use tie bands which permit a c flattening of cylinders of such tie bande in spirals is of tubing dialyaers which flattening of cellophane Especially preferred is a wire net upper lower support wires spaced apart distance substantially greater than the width of the tubing membrane and having a continuous of wire over wires at an angle of winding the wire the strand is spaced the support wires at equal tances such that a flow waoh solution will from about to The resulting net then one 3et of strands of wire running on parallel to each othe the support wires a corresponding set parallel to each other on the other side of wires When two of the resulting section net are as tie bands with a between the opposing of strands are pressed membrane sections against eaoh other and against the to channels membranes for flow of the wash At the same the bulges outwardly under flow of blood membrane sections flowing through At the crossing points of the membrane strands 9 both sides of the cellophane compressed in the shape of a point in case of addition of spacing strips are brought to one another to a membranes definite Between the the cellophane unfold depending on the prevailing pressure and the elasticity of the Depending on the size formed by the spacing the wound various membrances pouches of the cellophane within which the blood and between which the wash solution With increasing mush the extension membrances of the cellophane is ultimately by the fac p among that the pouches of neighboring membranes layers of the cellophane first touch at a and at greater finally along a In this way there is a maximum limit for the blood volume present membrane sections in the at any fixed With a sufficientl large mesh size one can dispense with the use of use of such nettings of wires crossing another for tio bands in an artificial kidney is regarded as The use of such tie bands are deemed advantagenoue also for in the case of known designs of artificial kidneys which include the use of porous The leak tightness of each end of the cellophane membrane at the transition to the inlet and the outlet of the blood tubes is effected by inserting an synthetic rubber or gum tube into end of the membrane and folding the around the elastic In the case of inlet folded end of the membrane and the blood are then passed through the narrow the inner diameter of a bore in the core confining on the inner periphery of the or preferabl detachable plastic conical The bore must have a smaller inner diameter than the outer diameter of the resilient blood tube so that it restrict the inserted The bore should be located in a polished tetrafluoroethylene pol or other synthetic the first being membrane so that the holding friction of the cellophane to be pulled through against the synthetic rubber or gum rubber is very much greater the friction between the bora wall and the rubber and In the case of sections the outlet the fastened similarly to the outer of the assemblyβ The artificial kidney is represented in the drawing in an illustrative but preferred 1 a central horisintal cross section through the artificial kidney assembly in operating 2 is a of the kidney in the first stage of its novel manner in schematic is a side view of the from the with individual parts in 4 shows greatly a detail of 3 in the longitudinal section 5 shows schematically the directions of solution through the channels formed by two tie bands with the membrane interposed between In one recognizes that in a plane metrical spiral 1 in the example of the embodiment there sections are coiled about a core 12 our 2a to one upon The beginning inlets and ends 11 of membrane sections the to 2d are substantially uniformly staggered along ciroumference of in the example of membrane sections by 90 Between the 2a to 2d are coiled porous tie bands 4a to in such a each tube is tightly and bordered by two tie The tie 4a to 4d consist in a of crossing strand wires In these cause of statistically homogeneously distributes pouches membrane sections 7 the to 2d during the dialysis membranes The ends 11 of the dialysis to 2d as shown especially in folded around a highly elastic terminal tube 9 and are pulled together with the latter under strong so as to be leakproof 9 through a conical 8 of a confining rim 10 in the outer casing artificial kidney The arrangement of the membrane sections ginnings and the ends of the to 2d is located advantageously on a uniformly of a In the example the embdsdimentj which uses four membrane sections beginnings and ends of the latter are staggered Q sections each by 90 on the tubing if three were would obtain a distance of With membrane sections the of more than four the circle would be uniformly divided Expressed geometrically 9 membrane section the beginning and end of each 2a to 2d there ore are located on the generatrix of the spiral In the solid arrows indicate the direction of flow of the wash solution on the front surface of the of the membrane and the dashed arrows indicate the direction of flow of the wash solution on the back surface of the The area within the sections of pairs of the upper and lower wires 6 filled section by the under blood flow pressure to form a pouch Each surface of the pouch 7 is thus washed by wash solution flowing as indicated by the As be seen in when the strands of wire on the front side the netting are positioned at the strands of wire the or opposite side are at an angle of along the Λ mulitplicity of pouches 7 thus is The improved artificial kidney of the invention is and used in a known the sterilized artificial kidney is installed in a sterilized dialyzer chamber having openings through which the inlet and outlet blood tubes by means of leakproof ease of use the inlet of each blood flow membrane section with the other inlets to a single main connection which leads to a line coming from the membrane sections p The outlets of the blood flow similarly joined to a main outlet line going back to the solution of known through the chamber through suitable The flow of was solution in the chamber is arranged 00 that in through the the solution is forced through artificial kidney through channels formed by the wires 6 of netting 5 of the tie bands The solution washes over the outer of the pouches 7 formed by the membranes and tie removing the waste products dialysed through the membranes from the blood passing through sections the membrane The blood to be by the membrane sections solution is circulated through the blood flow artery and ie discharged back to a vein by the force of the own blood no pump usually being In one embodiment of the improved artificial kidne the wire distance was approximately 5 mm and wire was 1 mm The wires were run at a Even netting was pulled tightly over the blood passed through readil and spacers were not Various lengths and numbers of tubing can be Pour coils of 4 meters of Visiting casing were found to contain a total of between 450 and 490 and to 2 vide a surface area of 00 cm A clearance of sodium ions of between 140 to 150 was obtained at a blood flow rate o 200 A maximum clearance of 220 was reached at a flow of 400 in The blood flow resistance of improved artificial kidney is When tested with a waterhead of 100 that roughly 75 produced a flow of The coils are In a clinical in one patient with a systolic blood pressure of 14Ό a blood flow of 100 was obtained without a Many different embodiments of this can be made without departing from the scope and spirit of as will be obvious to those skilled in the and it is to be understood that the invention includes all such bodiments and is not limited by the above it must be stated that the artificial kidney is to as a device used in medical research It is used in surgery for man and animal alike and for research purposes during lectures and insufficientOCRQuality

Claims (2)

1. WHAT IS CLAIMED ISi 1. In an artificial kidney device having a pair of permeable membrane sections with a pair of adjacent inner faces and. adapted for exchanging material between a first fluid in a path between said inner faces and a second fluid disposed in engagement with the outer faces of said membranes sections, the improvement characterized as a support for such membrane sections comprising* a first set of parallel strands supporting continuously along their lengths the outer surface of one of said membrane sections, and a second set of parallel strands supporting continuously along their lengths the outer surface of the other of said membrane sections and disposed at an angle to said first set of strands, said strands arranged to form two sets of flow channels disposed at an angle relative one another in said membrane sections under pressure of a first fluid.

2. A device as claimed in claim^ wherein the strands o^-w&pee- are made of a plastic material, each permeable 3· A device as claimed in clalml herein the/membrane is a coiled flattened tubing. k» A device as claimed in claim 1» 2 or 3» wherein both sets of strands form an angle with the upper and lower edges of the coiled membrane.sections. -if- 5. A device as claimed in claim 3 or h wherein the co flattened tubing membrane is made of cellophane. 6» A combination according to Claim 1 in which the strands and membrane are disposed in a spiral configuration, w th each set of strands occupying a separate spiral plane* 7. A combination according to Claim 1 in which each set of strands is disposed at an angle other than perpendicular to the other set. raemb an©-βee*ione-eemp iβe-a tube. 8 A combination according to any of the foregoing claims wherein said sets of strands are arranged in overlaying relationship, one with the other and comprise a unitary support member. 9ffl* A combination accordin to Claim 6 in which each set of strands is overlaid at an angle with a set of parallel strands and connected thereto at the points of intersection of the sets of strands. loyy. In an artificial kidney using as a dialyzer a flattened tubing of plastic film supported between foraminous bands of netting, the improvement which comprises a spiral assembly of said dialyzer tubing positioned between, said bands and positioned about a core, each band comprising a first set of parallel tuning strands lying against said butiagT the strands of each of one band said first se /defining an angle with respect to the strands of the first set of the band on the opposite side of said dialyzer tubing for forming flow channels, P.A. No* 26988 Ik.VIII.69 Pile 15997 1 l . An artificial kidney as claimed in any of Claims o 1 to li( which is free of spacers separating said bands. 2 . 0 1 . An artificial kidney as claimed in Claim 1% in which said bands comprise a unitary strip of plastic netting disposed in face to face contact with said dialfrzer tubing and coiled together into a spiral. 1$. An artificial kidney device, substantially as hereinbefore described and with reference to the drawings 1 . A combination according to Claim l in whioh bands of netting said -^up^oa^-member- is a plastic netting arranged in a coll about said pair of membrane sections. 13» A combination according to any of the proceeding claims in which the strands o each set defines a unitary support member, each member having a plurality of other strands of another set disposed at an angle to, and continuously along their lengths projecting away from, associated of said first and second strands. ■ 6 ΐή, In an artificial kidney as claimed in CIaim¾ using as a dialyzer a flattened ¾ubing of plastic film coiled spirally and embedded between foraminous bands of netting, the improvement which comprises a spiral assembly of dialyzer tubing positioned between said bands and positioned about a core, in which said band consists Of a netting of crossing strands comprising an upper set and a lower set of parallel strands, level in a plane, and each set of crossing strands supporting P. A. Ho . 26988 and lying against opposing sides of said dialyzer tubing and defining an angle to each , other , tjhich in use during dialysis in combination with said dialyzer tubing causes a formation of statistically horaogeneously distributed interconnected pouches along said dialysis tubing to define flou channels. 10. An artificial kidney, substantially as hereinbefore described and with reference to the drawings.