Analogue Fluid Flow Programming Structures

Abstract

A semi-automatic device for peroforming complex fluid processing procedures adapted to hemodialysis. The structure includes a disposable component formed by layers of transparent, flexible plastic sheets, sealed to each other according to a predetermined pattern defining between each pair flow paths and pockets which respectively form fluid passages and reservoirs. The structure also includes a permanent installation which is to receive the disposable component in order to form therewith a complete apparatus for automatically processing fluids, such as treating or determining the characteristics of a fluid such as human blood, according to predetermined sequences which may be controlled by internal and/or external information processing devices.

Description

BACKGROUND OF THE INVENTION

The present invention relates to fluid processing structures.

In particular, the present invention relates to structures used for testing or treating fluids as by determining predetermined characteristics of the fluids or by changing the characteristics of the fluids. In the case of human blood, for example, various tests may be carried out in order to determine the characteristics of the blood, and/or certain treatment may be made in order to change the characteristics of the blood.

At the present time systems of this type require the services of highly skilled personnel such as physicians nurses, and technicians of many different types. The processes involved are fairly complex. It may be necessary to carry out many different procedures on a fluid such as human blood during complex treatments such as hemodialysis. Accomplighing this with conventional processes this becomes extremely expensive and time consuming. This cost, further aggravated by the unavailability of skilled personnel even when funds are available, often makes therapy unavailable to patients requiring it for maintenance of their lives or well being. The equipment required for the above purposes is exceedingly delicate and expensive. A considerable amount of training is required for proper operation of such equipment and for proper evaluation of various tests of its effectiveness. This device, embodied exemplifying almost complete integration of the procedures of hemodialysis into an automatic system, is suitable for mass-production and distribution. Similarly designed systems could app1y to automated monitoring and therapy of shock, or diabetic keto-acidosis, and other situations frequently encountered is specialized, hospital intensive care units. They would significantly improve care in these situations by altering the balance of personnel time between performance of required procedures and decision-making based upon repeated evaluation of the results of therapy. Pertinent information could be made rapidly and continuously available. Anticipated therapeutic alternatives could be rapidly instituted. Automated medical systems could also extend emergency capabilities, for example, providing therapy for cardiac arrest with rapidly available cardio-pulmonary bypass. With present methods the costs of these diagnostic and therapeutic possibilities are prohibitive.

SUMMARY OF THE INVENTION

It is accordingly a primary object of the present invention to provide fluid processing structures which will avoid the above drawbacks, to improve the efficiency of existing medical facilities, and provide extension of servies to additional patients at reduced cost.

In particular, it is an object of the present invention to provide a fluid processing structure which can be automated and computerized to the extent that all the desired test and other operations of a particular procedure can be carried out by an extremely small number of operators who need not be particularly skilled.

Another object of the present invention is to provide, for systems of this type, a permanent installation which includes the relatively expensive controls, and a disposable component, containing the active principles of the procedure in a spatially ordered configuration which can be manufactured at an extremely low cost, to be used in conjunction with the permanent installation in order to carry out the required fluid processing operations.

Another object of the disposable component is to anticipate the logical relationships of, and provide the fluid flows required for performing the desired procedures, including sequences of flows, proportioning of predetermined mixtures, and other such necessary functions, within the patterns of flow paths and reservoirs formed by seals between adjacent layers of plastic sheets.

Also, it is an object of the invention to provide a disposable component with sterile packaging, where necessary, and sealed functional construction, whereever possible.

The unit is keyed to interact in the prescribed manner with the external hardward, the operative components consisting of various non-invasive value and pump mechanisms.

This construction reduces preparation time and complexity. It anticipates the steps in preparation for a procedure in the integrated design and automated sequences of function.

Also, it is an object of the invention to improve safety of the procedures especially when directly involving patient's therapy. Standardization of design and functions will prevent accidents of omission, minimizing possible patient errors, and with appropriate monitoring, control for intrinsic malfunctions. The sealed construction, and materials used, will provide insulation against electrical hazards.

A further object of the invention is to include in the disposable component as many functional control systems as can be compatible with low cost, affording a reduction to a minimum the size, expense and complexity of the permanent installation required.

In particular, it is an object of the invention to provide a disposable component which can be used with a permanent installation in such a way that relatively complex tests and other treatment or processing can be carried out in a purely automatic manner giving readings and the like which can be used with logic systems of computers in order to determine, with a high degree of accuracy and at relatively low cost, the information required in connection with the fluid which is processed.

According to the invention the structure includes a permanent installation and a disposable component to be used therewith. The permanent installation includes a wall having a front face formed with a predetermined pattern of grooves, recesses, and when necessary inlet and outlet connections. An access door is located adjacent the front face of the wall to hold a disposable component between these rigid structures. The disposable component includes at least a pair of transparent, flexible plastic sheets which are sealed to each other according to a predetermined pattern which will define between the sheets predetermined fluid passages and pockets providing predetermined flow paths and reservoirs, respectively, for the fluid which is to be processed, and containing the constituents of the procedure that will be consumed, contaminated or otherwise rendered ineffective for repeated use. These passages and reservoirs will register with the grooves and recesses of the wall of the permanent installation. This latter installation will have controls in the form of valves, photocells, pumping units, electrical contacts, and the like, coacting with the transparent sheets in order to control the flow of the fluids, perform designated tests, as well as provide predetermined treatment thereof. There may be inlets and outlets, where necessary, to perform transportations of aliquots of fluid automatically removed from the disposable component's fluid flow flow programming, or to inject functionally active fluids in any of the preprogrammed layers of the disposable component.

BRIEF DESCRIPTION OF DRAWINGS

The invention is illustrated, by way of example, in the accompanying drawings, which form part of this application and in which:

FIG. 1 is a schematic front elevation illustrating the manner in which the invention is applied to a hemodialysis system;

FIG. 2 is a front elevation of the wall of the permanent installation, FIG. 2 also schematically illustrating the control unit and fragmentarily showing access door in an open position; and

FIG. 3 is a fragmentary sectional plan view, taken along line 3--3 of FIG. 1, in the direction of the arrows, and showing in section, part of the walls of the permanent installation and part of the disposable component situated therebetween, FIG. 3 also showing one type of interface with various valves and pressure-sensing devices, as well as part of a pumping means.

DESCRIPTION OF PREFERRED EMBODIMENTS

In the drawings, the invention is shown as applied to a hemodialysis system, but it is to be understood that the principles of the invention are of general applicability to all types of systems where relatively complex manipulations of fluids are required.

Referring to FIG. 1, there is schematically represented therein a hemodialysis system 10 which includes a permanent installation 12 and a disposable component 14.

The permanent installation 12 of the system 10 includes a pair of lateral stands 16 which serve to carry the entire system on a balance apparatus (not shown) and functionally contained in the permanent installation 12. To the left of rear control wall 18 (FIG. 3) the installation 12 includes a control unit 20. This control unit has various operating buttons 22 and 24 which can be used to transmit suitable electrical signals for selecting a predetermined operation. The entire system is connected to a suitable source of electrical energy through the cord 25 which has the grounded plug 26 which can be inserted into any suitable wall outlet. The assembly 20 also includes devices for transmitting signals to a computer so that the various items of information can be automatically obtained and processed. If desired the computer structure may itself be housed within and form part of the unit 20.

As may be seen from FIG. 3, the rear control wall 18 is formed at its front surface, which is visible in FIG. 2, with various recesses 28 and grooves 30 defining a predetermined pattern of the recesses and grooves for a purpose referred to below. Also, the rear wall 18 carries at a pair of the recesses 28 suitable pumping devices 32 communicating with the interior of the recesses and acting to pump fluids in a manner described in greater detail below. The illustrated structure also includes various control and detecting devices such as the schematically represented valves 34 and photocells of conductivity detectors 36.

At its right end the rear wall 18 is connected by a hinge 38 with the front wall 40 which is transparent, preferably being made of any suitable clear plastic, with a pattern of grooves and recesses corresponding to those of the control wall. At its end which is distant from the hinge 38 the front wall 40 carries a suitable latch or releasable lock device capable of coacting with a catch 42 for releasably holding the transparent front wall 40 in its closed position adjacent the front surface of the rear wall 18 which is visible in FIG. 2. When the front wall 40 is in its closed position it serves to retain between the wall 40 and the wall 18 a disposable component 14.

The rear wall 18 also carries a pair of vertical bars 44 respectively terminating at their top ends in eyes 46.

The disposable component 14 is made up of layers of transparent flexible sheets which are sealed to each other according to a predetermined pattern. For example in the hemodialysis system to be described, a pair of these sheets 62 may be made of a clear plastic such as polyethylene, although other suitable plastics may be used. The pattern according to which these sheets are sealed to each other will create fluid passages 48 and pockets 50 which define flow paths and reservoirs, within the disposable component for the fluid which is to be processed and to contain necessary reagents or active principles of the process or procedure.

A mounting means is provided for mounting the disposable component 14 on the permanent installation. This mounting means in the illustrated example takes the form of a rod 52 which extends through an open-ended tube 54 which is defined along the top edge of the component 14 by the sealing of the sheets thereof to each other. Thus with the rod 52 extending through the tube 54 the entire disposable component 14 can be mounted on the permanent installation 12 simply by placing the ends of the rod 52 in the eyes 46.

The pattern of sealing of the plastic sheets to each other to form the disposable component 14 is such that the component 14 will have fluid passages and pockets which register with the grooves and recesses visible in FIG. 2. In addition it is to be noted that the area of sheets which form the disposable component 14 is substantially greater than the area of the front surface of the rear wall 18 so that these sheets of the component 14 extend a considerable distance above and below the walls of the permanent installation 12. At these areas above and below the walls, the disposable component 14 has additional pockets and passages as well as connections for fluid-supply and discharge lines, as referred to in greater detail below.

Referring to FIG. 2, it will be seen that the rear control wall 18 carries at its rear surface a housing 56 in which are housed various actuating and sensing units with suitable interfaces or connections incorporated in the structure of the control wall 18. For example the photocell units 36 actuated by the light which passes from a source in the control wall, through the disposable component 14, to be reflected by mirrored surfaces on the inside of the door to activate a photo detector on the control wall. These are connected in electrical circuits enabling the photocell units 36 to detect significant air or fluid levels in the fluid flowing within the pathways of the disposable component. The housing 56 also contains suitable solenoids, or motors capable of displacing armatures 58 which form valve plungers. As is apparent from FIG. 3 the disposable component 14 is composed of transparent plastic sheets 60 and 62 which are sealed to each other at their interface 64 so as to define between themselves the passages such as the passage 66 indicated in FIG. 3. The sheets which form the disposable component 14 also may be provided with openings through which locating pins 68 pass for providing a precise positioning of the disposable component on the permanent installation. It is furthermore to be noted that the front wall 40 is provided at its rear surface with recesses and grooves matching those at the front surface of the rear wall so that the disposable component 14 is precisely positioned between the walls of the permanent installation in the manner illustrated in FIG. 3. The various solenoid motors, or the like housed within the housing 56 are designed to be actuated in appropriate sequences by the electrical circuits activated by the operating buttons 22 and 24, with the result that a plunger such as the plunger 58 of FIG. 3 can be advanced to the position shown in FIG. 3 for closing a fluid passage. When this plunger 58 is retracted then the passage will be opened. In this way suitable valve controls are provided for determining the pathway and timing of the fluid flows. A second plunger 68 is shown in its retracted position maintaining the passage 66 open. Additional active surfaces along the functional grooves of the control wall 18, such as the plunger 70 shown in FIG. 3 may through suitable transducers detect pressure changes in the fluids within flow paths or reservoirs, to provide information for automatic operation. Furthermore, it is possible to incorporate elements, such as thermocouples, responsive to temperature changes, and contact points with conductive properties for electrical measurements. Appropriate interface manifolds incorporated in the disposable component will allow spectrophotometric measurements to be obtained, or access to the internal flow passage for inlet or outlet of fluids.

At other points along the grooves channels in the control wall 18 pumping means are incorporated, as designated by 32 in FIG. 2, shown in cross section in FIG. 3. This pumping can be provided by any suitable means for creating localized pressure differentials, as for example endless chains 72 driven from any suitable motor and supported by suitable sprockets 74 so that pumping rollers 76 will be advanced one after the other across the length of a pocket defined between the sheets, such as the pocket 80 which is fragmentarily illustrated in FIG. 3. The result is that each pumping roller 76 will push a quantity of fluid ahead and suck a quantity of fluid behind itself, thus bringing about a pumping action according to which fluid will be pumped from the left toward the right, as viewed in FIG. 3, with respect to the pocket or reservoir 80, in accordance with the desired flow characteristics of the particular circuit involved. Or this pumping means may be provided by external fluid pumping to provide alternately increasing or decreasing pressures of fluid contained in a "pumping" pocket, sealed except for inlet-outlet connections, in layers of plastic sheets outside the layers providing the primary passages and reservoirs, in a multiple layer configuration. Confined within the recesses of the control wall and door, introductions of fluid under pressure into these pumping means will transmit this pressure to the inner fluid volume, forcing it to exit via the passages open to it. These exit passages can be similarly controlled by higher pressure, non-parallel intersecting fluid flow circuits forming valves, to provide unidirectional flow. The introduction of proportional resistances in such pressure regulates flow paths can, in addition to reservoir and passage dimensions, provide volumetric controls.

Considering now the specific hemodialysis system which is shown in the drawings, the sheets which form the disposable component 14 define between themselves a pair of passages 102 and 104 terminating at their left ends, as viewed in FIG. 1, in connections 106 and 108, respectively, adapted to be connected with suitable liquid-supply lines. Thus, at this part the sheets may have suitable rigid plastic connecting valves for example, inserted into the open ends of the passages 102 and 104 sealed to the sheets so as to form a fluid-tight connection. Flexible tubes may be attached to the valve connectors 106 and 108 so that sources of water can be connected with the passages 102 and 104. These sources of water may be distilled or tap water, for example, or from hot and cold sources. It will be noted from FIG. 2 that the lower portions of the passages 102 and 104 register with grooves 110 and 112, respectively, provided with valves 114 and 116 so that in this way the source or temperature of liquid can be regulated. The supplied liquid will flow along the passage 118, part of which registers with the groove 120 into the water purification reservoir 122 formed by one of the pockets 50 defined between the sheets. This reservoir 122 communicates through the passage 124, which registers with the groove 126 into a reservoir 128 which forms a water reservoir and which registers with the recess 130, at the lower portion of the reservoir 128. At this part of the apparatus there is one of the photocell conductivity detectors 36 to transmit a signal giving information with respect to the level or quantity water in the reservoir 128. The water purification carried out in the reservoir 122 will be performed by enclosing within the reservoir 122 before the sheets are sealed to each other a device containing filters and suitable chemicals adapted to the particular nature of the water supplied so as to sterilize and deionize the water, and provided with characteristics suitable for the purpose intended. The reservoir 128 communicates through a passage 132 with a reservoir 134 registering with one of the recesses 28 and adapted to contain a saline concentrate. The admission of the saline concentrate, contained in pocked 134 FIG. 1 to the water from reservoir 128 is controlled by coaction of a value 136 and the internal structure of the disposable components proportioning resistances to create uniform mixtures, as will be described below.

Through this value the reservoir 128 will communicate with a passage 140 leading to a saline reservoir 142 situated above the walls of the permanent installation and communicating with an air trap 144 which in turn communicates through a passage 146 with an air pressure monitor pocket 148 registering with the recess 150. An active surface such as the plunger 70 shown in FIG. 3 will sense the pressure contained within the system reservoir 148 at the recess 150. It will be noted that part of the passage 146 registers with the groove 152.

The reservoir 126, at its location above the permanent installation communicates through a suitable passage with a second air trap 154 defined between the sheets of the disposable component 14 and communicating through the passage 156, also defined between the sealed sheets, with the air pressure monitor pocket 148. Through the combination of these air traps, photocell-conductivity fluid level detectors 36, and fluid pressure sensitive devices in the control wall recesses, adequate levels of liquid can be maintained to supply the functional requirements of the various circuits, while avoiding the danger of introducing air bubbles into the fluid circulations.

From the passage 132 purified water flows under hydrostatic pressure into passage 140 and reservoir 142, and by gravity into a passage 158 registering with the groove 160. Valves 136 and 164 control the delivery of the purified water to either saline 140, or dialysate 158, circuits. Valve 164 coacts with the internal resistance adjustment and predetermined volume of the disposable component to proportion the mixture of purified water from reservoir 128 and dialysate concentrate from reservoir 166, under controlled pressure within recess 168, to form dialysate.

Passage 158 then communicates through the three passages 170, 172, 174, with the dialysate reservoirs 176 and 178. These passages 170, 172, and 174, respectively register with the grooves 180, 182, and 184, which are controlled by the valves 186, 188, and 190, so that in this way the control of the flow through the various passages 170, 172, and 174 can be regulated to determine the flow of the dialysate, as it is formed, alternately into the dialysate reservoirs 176 and 178.

It will be noted that through the passages 172 and 174 the flow can be controlled to the reservoirs 176 and 178 while through the passage 170 it is possible to provide for direct flow of the liquid in this circulation to a waste reservoir 192 in the form of a pocket defined between the sheets of the disposable component 14. This waste reservoir 192 has at its left end, as viewed in FIG. 1, a value 194 through which the contents may be drained.

From the dialysate reservoirs 176 and 178 the liquid can flow through the passages 192 and 194 into a common passage 196 leading into a dialyzer 198. It will be noted that the dialyzer 198 can be a standard device contained between the sheets of disposable component 14 beneath the wall of the permanent installation. The passages 192 and 194 respectively register with the grooves 200 and 202. These grooves are respectively provided with control valves 204 and 206. The recesses 208 and 210 respectively register in part with the dialysate reservoirs 176 and 178 and they are provided with heating element surfaces 212 and 214 as well as photocell-conductivity detectors 36 and thermocouples capable of detecting the nature and level of the dialysate in the reservoirs 176 and 178. In accordance with the characteristics detected in this way and the programming of the permanent installations to alternately fill and empty dialysate reservoirs one or the other of the valves 204 and 206 will be opened to admit the dialysate into the dialyzer 198. In the dialyzer the blood from the patient will be treated in a standard manner by dialysis and ultrafiltration across a suitable membrane. Such a membrane is incorporated into the dialyzer 198. The dialysate will be pumped by the upper pump means 32 at the pumping pocket 216 received in the pumping recess 28, so that this liquid will be pumped through the passage 158 back into the empty dialysate reservoir 176 or 178 thus achieving recirculation if desired, or to waste. Between the dialyzer 198 and the pump reservoir 216 is a passage 220 which communicates through a pocket 222 with the pump reservoir 216. At this pocket 222 is the recess 224 of the rear wall 18, and at this recess is located a suitable standard hemoglobin detector carried by the rear housing 56.

A dialysate purification reservior 226 is defined between the sheets of the disposable component 14 and registers with the recess 228 shown in FIG. 2. The rear wall carries at the connection between the recess 228 and the recess 224 the valves 230 and 232 so that in this way the flow from the dialysate purification pocket along the recirculating passage 234 can be regulated. This passage 234 registers with the groove 236 shown in FIG. 2, and it will be noted that an additional valve 238 is provided to control the flow through the passage 234.

Thus, through control of the operation of the valves 232 and 238, with suitable settings of the operating buttons at the control panel 20, it is possible to circulate the dialysate through the dialysate purification reservoir 226, containing suitable exchange and binding resins, chemicals and reagents to regenerate used dialysate. These components of the procedure, as well as all the others such as saline and dialysate concentrates, and the reagents necessary for appropriate chemical anaylsis within the sealed analyzer unit 276, are situated at locations destined to form pockets or reservoirs according to the predesigned patterns and flows and fluid manipulations necessary to perform the selected procedure, preliminary to sealing the flexible plastic sheets to each other to form the disposable component.

All of the above detailed description in connection with the specific example of a hemodialysis system relates to the features which are used in connection with obtaining and circulating of dialysate. It is of course also required to provide an extracorporeal circuit and suitable safety monitoring, for the blood of the patient so that the blood can pass through the dialyzer for treatment, and then be returned to the patient. For this purpose the sheets which form the component 14 are heated sealed to define a passage 240 formed with an inlet connection to receive the flexible line 242 which is connected in standard ways with the blood system of the patient in the manner shown schematically in FIG. 1. In this way blood from the patient will enter into the hemodialysis system. The lower pump means 32 which has the pumping rollers 76 moving horizontally from the left toward the right, as viewed in FIGS. 2 and 3, communicates with the passage 240 through a passage 243 defined between the sheets due to the sealing thereof. These passages 240 and 242 respectively register with the vertical and horizontal grooves 244 and 246 formed in front surface of the rear wall 18, as shown in FIG. 2.

The saline reservoir 142 communicates with the passage 243 to allow saline priming of the extracorporeal circuit, through a vertically extending passage 248 which registers with the vertical groove 250 formed in the front surface of the rear wall 18. Thus, the blood will be pumped into the passage 252 formed between the sheets of disposable component 14, and in this way the blood will reach the dialyzer 198. This passage 252 which receives the blood registers in part with a groove 254 provided with an enlarged recess portion 256 where a blood pump pressure monitor is mounted within the housing 56 so as to detect the pressure of the blood pumped by the lower pump means 32.

The pumped blood will thus flow through the dialyzer 198 in countercurrent to the dialysate, with the processing taking place through a suitable membrane within the dialyzer 198, as is well known, and then the blood will reach the dialyzer outlet passage 258 defined between the sheets of disposable component 14 through the sealing pattern. This passage 258 communicates with a reservoir 260 formed by a pocket defined between the sealed sheets, and this reservoir will register with the recess 262 formed in the front surface of the rear wall 18. The upper part of the passage 258 will register with the groove 264. The reservoir 260 forms on the one hand a bubble trap and on the other hand a blood return line monitor. For this purpose there are a pair of photocells and electrical conductivity detectors 266 and 268 carried by the rear housing 56 and communicating with the interior of the recess 262 so that the level of the blood returning to the patient in the reservoir 260 can be detected, thus preventing air embolism from occurring. The pressure of returning blood is monitored by detector 300. From the blood monitoring reservoir 260 the blood returns to the patient through a passage 270 defined between the sheets of the component 14 and placed in communication with a flexible line 272 which again is connected with the patient, as shown schematically in FIG. 1.

However, part of the blood may be delivered through a passage 274 into a blood analyzer 276 defined between the sheets. The passage 274 registers with a groove 278 in the front surface of the rear wall 18, and at this point there is a valve 280 which can be controlled from the panel 20 so as to regulate the flow of blood into the analyzer portion of the disposable component 276 which registers with the recess 282 formed in the front surface of the rear wall 18.

The analyzer component contains fluid passages and reservoirs, as well as pockets for reagents, and structures suitable to perform the manipulations necessary for chemical analysis of significant characteristics of the dialyzed blood. These operations of flow, mixing, proportioning, filtration, dialysis and so forth, are performed in a manner similar to the procedures of hemodialysis, but on a smaller scale, and can be adapted, as well, to function independently from such large units as the hemodialysis system, as a means of automating laboratory testing.

The passage 240 communicates also with a reservoir 284 which contains suitable anticoagulant material to be fed to the passage 242 in order to flow with the blood so as to prevent coagulation thereof. For example a suitable stabilized heparin composition may be initially located within the pocket 284 and controlled by a unit in the housing 56 so as to feed to the blood flowing the dialyzer a sufficient amount of anticoagulant in order to keep the blood flowing freely at all times through the apparatus.

It is thus possible with the above structures of the invention to carry out hemodialysis in a fully automatic manner, achieving through computer information processing techniques a considerable amount of precise control in a manner which heretofore required the operations of skilled personnel and expensive equipment. All of the relatively expensive components form part of the permanent installation 12 while the disposable component 14 is quite inexpensive to manufacture. The sheets are heat sealed to each other to define the predetermined reservoirs and flow paths and to contain in certain pockets suitable reagents, and this inexpensive disposable component 14 can readily be mounted on the permanent installation in a manner described above. The operator need only connect the connections 106 and 108 to suitable sources of water, and after the saline and dialysate have been provided in a suitable manner between the sheets of component 14 the lines 242 and 272 are connected with the patient and the hemodialysis can then proceed. After the operations are completed all of the lines are disconnected and the component 14 may be removed to replace by another component to be used with the next patient. The removed component 14 may be preserved or it may be discarded. With this system of the invention it is possible for unskilled and relatively untrained individuals to be given simple instructions for initiating the sequential operations necessary to perform a complex procedure such as hemodialysis. These may be reinforced by the internal programming of the unit, and by indicator lights associated with the control buttons 22 and 24. The mounting of the component 14 on the permanent installation becomes fairly automatic, and the same is true of the connection of the water and blood lines. Therefore, this system accomplishes its prime objective, the speeding and simplification of procedures necessarily performed by human actions in providing complex medical diagnostic or therapeutic techniques. The invention shown utilizing this system, is extremely well suited for hemodialysis treatments to be performed by patients at home, a development that has been found necessary if all patients requiring this form of treatment are to have it made available.

Claims

What is claimed is:

1. For use in the processing of fluids, at least a pair of flexible plastic sheets sealed to each other according to a predetermined pattern defining between said sheets fluid passages and pockets situated inwardly of and spaced from the peripheries of said sheets and forming predetermined flow paths and reservoirs, respectively, for the fluid which is to be processed and for containing necessary active principles of the processing, said sheets having inlet and discharge connecting portions to be connected with fluid supply and discharge lines, respectively.

2. The combination of claim 1 and wherein the pattern of sealing of said sheets to each other defines also valve and pumping mechanisms adapted for pumping fluid along said passages and into and out of said reservoirs.

3. The combination of claim 1 and wherein said sheets are transparent so that fluid between the sheets is visible and can have characteristics thereof detected by light-signal systems.

4. The combination of claim 1 and wherein said sheets include a mounting portion for adapting the sheets to be mounted on an apparatus which coacts with the sheets.

5. In an apparatus for processing fluids, a permanent installation and a disposable component to be used therewith, said permanent installation including a control wall having a front surface formed with recesses and grooves according to a predetermined pattern and an access wall with similar recesses and grooves located adjacent said front surface of said control wall for holding a disposable component in engagement with said front surface of said control wall, said disposable component including flexible plastic sheets sealed to each other according to a pattern providing passages and pockets which are situated inwardly of and spaced from the peripheries of said plastic sheets and which respectively register with said grooves and recesses, said passages and pockets providing predetermined flow paths and reservoirs, respectively, for fluid to be processed, and for containing necessary active principles, and said permanent installation including at said control wall thereof control means communicating with or coacting with said passages and recesses for controlling the flow of fluid in the passages and pockets of the disposable component.

6. The combination of claim 5 and wherein the control means carried by said control wall includes valve plungers for pressing the sheets of said disposable component together at the passage defined therebetween and for releasing the sheets from each other at the passages so as to close and open, respectively, predetermined fluid passages defined between the sheets.

7. The combination of claim 5 and wherein said sheets are transparent, and said control means including light-responsive devices responding to the passage of light through said sheets for receiving signals indicative of the characteristics of the fluids, said front wall being transparent so that light can pass through the sheets to provide visibility of the ongoing processes.

8. The combination of claim 5 and wherein said sheets of said disposable unit include inlet and outlet connections.

9. The combination of claim 5 and wherein a mounting means forms part of said permanent installation and coacts with said disposable component for mounting the latter removably on the permanent installation.

10. The combination of claim 5 and wherein said disposable component includes sheets, the area of which is greater than that of said rear wall, said sheets having portions extending beyond said walls of said permanent installation and defining additional pockets and passages for the processed fluid.

11. The combination of claim 5 and wherein said permanent installation and disposable component form a hemodialysis and analytic monitoring system, said pockets and passages forming a flow path for blood and a flow path for dialysate, and all structures and participant materials necessary for the procedure.

12. The combination of claim 5 and wherein said control wall carries pumping means communicating with said recesses, said sheets defining between themselves pumping chambers communicating with the latter recess, said pumping means coacting with the disposable component at said pumping chamber thereof for pumping fluid therethrough.

13. The combination of claim 1 and wherein said sheets form portions of active controls and pumping mechanisms by interactions such as transfer of heat, or pressure relationships between fluid in adjacent layer flow paths, or via volumetric sizing of the flow paths and reservoirs.

14. For use in the processing of fluids, at least a pair of flexible plastic sheets sealed to each other according to a predetermined pattern defining between said sheets fluid passages and pockets situated inwardly of and spaced from the peripheries of said sheets and forming predetermined flow paths and reservoirs, respectively, for the fluid which is to be processed and for containing necessary active principles of the processing, said sheets having inlet and discharge connecting portions to be connected with fluid supply and discharge lines, respectively, said sheets defining non-parallel intersections of control paths with procedural paths functioning as valves by the action of higher pressure in the control paths to occlude the flow path lumen.

15. The combination of claim 14 and wherein said sheets have series of pressure activated intersections to function as pumping mechanism.

16. The combination of claim 13 and wherein said sheets have proportional resistances within the flow patterns to proportion the volumes of fluids passing through them.

17. For use in the processing of fluids, at least a pair of flexible plastic sheets sealed to each other according to a predetermined pattern defining between said sheets fluid passages and pockets situated inwardly of and spaced from the peripheries of said sheets and forming predetermined flow paths and reservoirs, respectively, for the fluid which is to be processed and for containing necessary active principles of the processing, said sheets having inlet and discharge connecting portions to be connected with fluid supply and discharge lines, respectively, said sheets defining intersecting control paths with procedural paths functioning as pressure sensors in procedural path to proportionally alter resistance characteristics of control path circuits operating in conjunction with fluidic logic circuits or other pressure or flow sensing mechanisms to react to significant changes in the procedural flow paths functions.