Hemodialysis system comprising a dialysate generator

Abstract

A portable hemodialysis system is provided that includes a dialyzer, a closed loop blood flow path that transports blood from a patient to the dialyzer and back to the patient, and a closed loop dialysate flow path that transports dialysate through the dialyzer. The hemodialysis system includes a hemodialysis machine and a dialysate generator that are physically connectable and disconnectable to each other. To connect the hemodialysis machine and the dialysate generator together, both the hemodialysis machine and the dialysate generator have connectable and disconnectable electrical connectors and fluid connectors that are positioned and configured to allow fluid and electrical connections between the two machines. The hemodialysis machine includes a processor and a user interface, preferably in the form of a touchscreen, that is capable of controlling the functions of the hemodialysis machine and the dialysate generator.

Description

TECHNICAL FIELD

[0001] The present invention relates to an artificial kidney system for providing dialysis. More specifically, the present invention relates to a hemodialysis system comprising a machine for generating dialysate.

[0002] The Applicant hereby incorporates by reference any and all patents and published patent applications cited or referred to in this application. BACKGROUND

[0003] Hemodialysis is a medical procedure used to remove waste products, including creatinine, urea and free water, from a patient's blood while outside the body, involving diffusion of solutes across a semi-permeable membrane. Failure to properly remove these waste products can result in kidney failure.

[0004] During hemodialysis, a patient's blood is removed through an arterial line, processed through a dialysis machine, and then returned to the body through a venous line. The dialysis machine includes a dialyzer containing a large number of hollow fibers that form a semi-permeable membrane through which the blood is transported. In addition, the dialysis machine utilizes dialysate, which contains appropriate amounts of electrolytes and other essential ingredients (e.g., glucose), that is also pumped through the dialyzer.

[0005] Dialysis solution (also commonly referred to as dialysate) is an aqueous electrolyte solution that mimics extracellular fluid, differing only in the buffering bicarbonate and potassium. Dialysis solution is nearly isotonic, with an osmolarity of about 300 ± 20 milliosmolar per liter (mOsm / L). To ensure patient safety and prevent destruction of red blood cells due to hemolysis or cell crenation, the osmolarity of the dialysate must be close to that of plasma, i.e., 280 ± 20 mOsm / L. Dialysis solution typically contains six (6) electrolytes: sodium (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), chloride (Cl-), and bicarbonate. Dialysate also contains a seventh ingredient, the nonelectrolyte glucose or dextrose. The concentration of glucose in the dialysate is typically between 100 and 200 mg / dL.

[0006] Typically, dialysate is prepared by mixing clean water with acid concentrate and bicarbonate concentrate in appropriate proportions. Preferably, the acid and bicarbonate concentrates are separated until final mixing just prior to use in the dialyzer, as calcium and magnesium in the acid concentrate will precipitate out upon contact with the high bicarbonate content of the bicarbonate concentrate. Clean water used to prepare dialysate must be relatively pure, e.g., municipal drinking water is treated to an acceptable level of purity by a water purification system.

[0007] Water purification is the process of removing unwanted chemical substances, biological contaminants, suspended solids and gases from water, thereby reducing the concentration of particulate matter including suspended particles, parasites, bacteria, algae, viruses and fungi, and reducing the concentration of a range of dissolved and particulate matter. Water purification methods used include: physical processes such as filtration, sedimentation, distillation; biological processes such as slow sand filters or biological activated carbon; chemical processes such as flocculation and chlorination; and the use of electromagnetic radiation such as ultraviolet light.

[0008] The dialysis process across a membrane is achieved by a combination of diffusion and convection. Diffusion causes molecules to move from areas of high concentration to areas of low concentration by random motion. At the same time, convection causes solute movement, usually in response to hydrostatic pressure differences. Fibres forming the semi-permeable membrane separate the blood plasma from the dialysate and provide a large surface area for diffusion, allowing waste products including urea, potassium and phosphate to permeate into the dialysate, while preventing the transfer of larger molecules such as blood cells, polypeptides and certain proteins into the dialysate.

[0009] Typically, the dialysate flows in the extracorporeal circuit in the opposite direction to the blood flow. Counter-current flow maintains a concentration gradient across the semi-permeable membrane, thereby increasing the efficiency of dialysis. In some cases, haemodialysis can provide fluid removal, also known as ultrafiltration. Ultrafiltration is usually achieved by reducing the hydrostatic pressure of the dialysate compartment of the dialyser, thereby allowing water containing dissolved solutes, including electrolytes and other permeable substances, to move across the membrane from the blood plasma to the dialysate. In rare cases, the fluid in the portion of the dialysate flow path of the dialyser is higher than the blood flow portion, causing fluid to move from the dialysate flow path to the blood flow path. This is commonly referred to as reverse ultrafiltration. As ultrafiltration and reverse ultrafiltration can increase the risk to the patient, ultrafiltration and reverse ultrafiltration are usually performed under the supervision of trained medical personnel.

[0010] Unfortunately, haemodialysis has a number of drawbacks. One of the drawbacks is that a large amount of clean dialysate must be available. Typically, this is done by preparing the dialysate on site at a hospital or dialysis centre that treats a large number of patients. Unfortunately, the dialysis treatment within hospitals and centres requires patients to travel from their homes for three treatments per week, each treatment typically taking about 3 to 4 hours. Furthermore, patients must make appointments for these treatments, which requires them to schedule their day well in advance, which can impact their quality of life. Furthermore, haemodialysis treatments often cause patients to feel nauseous, cramping, dizzy and headaches, however they must adjust and tolerate this on their way home to recover.

[0011] To a lesser extent, patients perform hemodialysis at home. This reduces scheduling issues, as well as the burden of traveling to and from the clinic. However, home hemodialysis requires more frequent treatments, typically six days per week, with two-hour treatments. These treatments require the transport of large amounts of dialysate to the patient. Alternatively, the patient's home must be equipped with a water purification system, and the patient must prepare the dialysate themselves. Unfortunately, water purification systems suitable for preparing dialysate are currently expensive, often loud, and take up a significant amount of living space.

[0012] Home hemodialysis also suffers from other drawbacks. Current home dialysis systems are bulky, complex, intimidating, and difficult to operate. The equipment requires extensive training. Existing home hemodialysis systems are too large to be portable, thereby hindering the travel of hemodialysis patients. Home hemodialysis systems are expensive and require a high initial capital investment, especially in comparison to in-center hemodialysis, which does not require the patient to pay for the machine. Current home hemodialysis systems do not adequately provide for the reuse of supplies, making home hemodialysis economically unfeasible for medical suppliers. Due to the above drawbacks, few patients are willing to actively undertake the arduous task of home hemodialysis.

[0013] Accordingly, there is a great need for a hemodialysis system that is portable, lightweight, easy to use, patient-friendly, and thus capable of being used in a clinic or at home.

[0014] Moreover, it would be desirable to provide a hemodialysis system that includes a water purification system.

[0015] Furthermore, it would be desirable to provide a hemodialysis system that generates dialysate.

[0016] Aspects of the present invention meet these needs and provide further related advantages as described in the following summary of the invention. SUMMARY

[0017] According to a first aspect of the present invention, there is provided a hemodialysis system comprising a hemodialysis machine and a dialysate generator. The hemodialysis machine and the dialysate generator each comprise their own housing and are connectable and disconnectable to each other by electrical connectors and fluid connectors. Furthermore, it is preferred that the hemodialysis machine and the dialysate generator can be operated together, and that the hemodialysis machine and the dialysate generator can be operated and function independently from each other.

[0018] A hemodialysis machine includes an arterial blood line for connecting to an artery of a patient for collecting blood from the patient, a venous blood line for connecting to a vein of the patient for returning blood to the patient, and a disposable dialyzer. The arterial blood line and the venous blood line can be of typical construction known to those skilled in the art. For example, the arterial blood line can be a conventional flexible hollow tube connected to a needle for withdrawing blood from the artery of the patient. Similarly, the venous blood line can be a conventional flexible tube and needle for returning blood to the vein of the patient. Various configurations and surgical procedures can be employed to access the blood of the patient, including a venous catheter, an arteriovenous fistula, or a synthetic graft.

[0019] Preferably, the disposable dialyzer has a construction and design known to those skilled in the art, including a blood flow path and a dialysate flow path. The term "flow path" is intended to refer to one or more fluid conduits, also known as channels, for transporting fluid. The conduits can be constructed in any manner that can be determined by those skilled in the art, including, for example, a flexible medical tube or a non-flexible hollow metal or plastic housing. The blood flow path transports blood in a closed loop system through the arterial blood line and the venous blood line for transporting blood from the patient to the dialyzer and back to the patient. Simultaneously, the dialysate flow path transports dialysate in a closed loop system from a dialysate supply to the dialyzer and back to the dialysate supply.

[0020] Preferably, the hemodialysis system includes one or more reservoirs for storing dialysis solution. In one embodiment of the hemodialysis system, the one or more reservoirs are located in the hemodialysis machine. For this embodiment, the reservoirs are connected to the dialysate flow path of the hemodialysis machine to form a closed loop system for transporting dialysate from the reservoirs to the dialyzer of the hemodialysis machine and back to the reservoirs. More preferably, the hemodialysis machine has two (or more) dialysate reservoirs that can be alternatively placed within the dialysate flow path. When one reservoir has contaminated dialysate, dialysis treatment can continue using the other reservoir while the reservoir with contaminated dialysate is emptied and refilled. The reservoirs can be any size required by the clinician in order to perform proper hemodialysis treatment. However, it is preferred that the two reservoirs are of the same size and small enough to enable the dialysis machine to be easily portable. Acceptable reservoir capacities are 0.5 liters to 5.0 liters. A preferred reservoir stores approximately 2.0 liters of dialysate.

[0021] The hemodialysis machine preferably has one or more heaters thermally coupled to the reservoir for heating the dialysate stored within the reservoir. In addition, the hemodialysis machine includes a temperature sensor for measuring the temperature of the dialysate within the reservoir. The hemodialysis machine preferably has a fluid level sensor for detecting the level of fluid in the reservoir. The fluid level sensor can be any type of sensor for determining the amount of fluid within the reservoir. Acceptable fluid level sensors include magnetic or mechanical float-type sensors, conductive sensors, ultrasonic sensors, optical interfaces, and weight measurement sensors (e.g., scales or load cells for measuring the weight of the dialysate in the reservoir).

[0022] Preferably, the hemodialysis machine includes three main pumps. Two of the pumps are first and second "dialysate" pumps, which are connected to the dialysate flow path for pumping dialysate through the dialysate flow path from the reservoir to the dialyzer and back to the reservoir. Preferably, the first pump is positioned in the dialysate flow path "upstream" of the dialyzer (meaning forward in the flow path), while the second pump is positioned in the dialysate flow path "downstream" of the dialyzer (meaning rearward in the flow path). Meanwhile, the third main pump of the hemodialysis machine is connected to the blood flow path. This "blood" pump pumps blood from the patient through the arterial blood line, through the dialyzer, and through the venous blood line to return to the patient. It is preferred that the third pump be positioned in the blood flow path upstream of the dialyzer.

[0023] The hemodialysis machine can also contain one or more adsorptive filters for removing toxins that are permeated from the blood plasma into the dialysate through the semi-permeable membrane. Suitable materials for the filter within are well known to those skilled in the art. For example, suitable materials include a bed of resin, which includes a zirconium-based resin. Acceptable materials are also described in U.S. Patent No. 8,647,506 and U.S. Patent Publication No. 2014 / 0001112. Other acceptable filter materials can be developed and utilized by those skilled in the art without undue experimentation. Depending on the type of filter material, the filter housing can include a vapor membrane capable of releasing a gas such as ammonia.

[0024] Preferably, the hemodialysis machine includes two additional flow paths in the form of an "effluent" flow path and a "fresh dialysate" flow path. The effluent flow path includes one or more fluid effluent lines for effluent of the contaminated dialysate from the reservoir, and the fresh dialysate flow path includes one or more fluid fill lines for delivery of fresh dialysate from a fresh dialysate supply to the reservoir. One or more fluid pumps can be connected to the effluent flow path and / or the fresh dialysate flow path to deliver fluid to their intended destinations.

[0025] Further, the hemodialysis machine includes a plurality of fluid valve assemblies for controlling the flow of blood through the blood flow path, for controlling the flow of dialysate through the dialysate flow path, and for controlling the flow of used dialysate through the filtration flow path. The valve assemblies can be any type of electromechanical fluid valve structure that one skilled in the art can determine, including but not limited to conventional electromechanical two-way fluid valves and three-way fluid valves. Two-way valves are any type of valve having two ports, including an inlet port and an outlet port, where the valve simply allows or impedes the flow of fluid through the fluid path. Conversely, three-way valves have three ports and are used to shut off fluid flow in one fluid path while opening fluid flow in another path. Further, the valve assemblies of the dialysis machine can include safety pinch valves, such as a pinch valve connected to the venous blood line, for selectively allowing or impeding the flow of blood through the venous blood line. The pinch valve is provided so as to pinch the venous blood line in the event an unsafe condition is detected and thereby prevent blood from flowing back to the patient.

[0026] Preferably, the hemodialysis machine contains sensors for monitoring the hemodialysis. To this end, preferably the dialysis machine has at least one flow sensor connected to the dialysate flow path for detecting the fluid flow (volume and / or velocity) within the dialysate flow path. Further, it is preferred that the dialysis machine contains one or more pressure sensors for detecting the pressure within the dialysate flow path, or at least one occlusion sensor for detecting whether the dialysate flow path is occluded. Preferably, the dialysis machine also has one or more sensors for measuring the pressure and / or fluid flow within the blood flow path. The pressure sensor and flow (flow rate) sensor can be separate components, or the pressure measurement and flow measurement can be done by a single sensor.

[0027] Further, it is preferred that the hemodialysis machine includes a blood leak detector ("BLD") that monitors the flow of dialysate through the dialysate flow path and detects whether blood has inappropriately diffused through the semi-permeable membrane of the dialyzer into the dialysate flow path. In a preferred embodiment, the hemodialysis machine includes a blood leak sensor assembly that contains a light source that emits light through the dialysate flow path and a light sensor that receives the light emitted through the dialysate flow path. The received light is then analyzed after passing through the dialysate flow path to determine whether the light has changed to reflect possible blood in the dialysate.

[0028] The dialysis machine preferably includes additional sensors, including an ammonia sensor and a pH sensor, for detecting the ammonia level and pH within the dialysate. Preferably, the ammonia sensor and pH sensor are immediately downstream of the filter in the dialysate flow path. Further, the dialysis machine has a bubble sensor connected to the arterial blood line and a bubble sensor connected to the venous blood line for detecting whether bubbles have formed in the blood flow path.

[0029] The hemodialysis machine has a processor that contains specialized electronics for controlling the hemodialysis system. The processor of the hemodialysis machine contains power management and control circuitry connected to the pump motors, valves, and dialysis machine sensors for controlling the normal operation of the hemodialysis machine. In addition, the hemodialysis machine includes a user interface connected to the processor for enabling a person to control the software and hardware of the hemodialysis machine. The user interface can include any electromechanical device that enables a user to interact with the processor, such as a display screen, keyboard, and / or mouse. In a preferred embodiment, the user interface is a graphical user interface in the form of a touchscreen. In addition, the hemodialysis machine can include simple electromechanical switches and / or mechanical valves, such as for turning the machine on / off, or for manually disabling any fluid conduits.

[0030] In addition, the hemodialysis system includes a machine for generating dialysate, referred to herein as a dialysate generator. The dialysate generator can utilize any known method and / or apparatus for purifying water, such as filtration, sedimentation, and distillation, or a combination of these. In a preferred embodiment, the dialysate generator contains a combination of carbon filtration, ultraviolet disinfection, and reverse osmosis (RO) filtration. In addition, the dialysate generator includes conduits that provide a fluid path that carries water from a water inlet through various filters, valves, heaters, mixers, pumps, ultraviolet disinfection units, sensors, and reagent sources to generate dialysate. Fresh dialysate is discharged from the outlet of the dialysate generator directly into one of the reservoirs of the hemodialysis machine.

[0031] In a preferred embodiment, water enters the dialysate generator through a water inlet. Thereafter, the water is transmitted through the flow path of the dialysate generator, which includes an inlet flow path, a main filtration loop, and an outlet flow path. The inlet flow path of the dialysate generator includes, in turn, a pressure regulator, a check valve, a first carbon and sediment filter, a sample port, and a second carbon filter (referred to herein as a carbon polisher). The carbon-filtered water is then directed through the main filtration loop, which includes an ultraviolet (UV) sterilizer, a water descaler, a temperature sensor, a pressure sensor, a conductivity sensor, a pump (preferably a membrane), and an additional pressure sensor, to a reverse osmosis membrane. The reverse osmosis membrane outputs a “clean water” and a “waste” effluent. The waste effluent from the reverse osmosis membrane is split by a bypass valve, with some of the waste effluent being discarded and another portion of the waste effluent being sent to a pair of parallel variable fluid orifices that controllably restrict the flow of water and create back pressure in the reverse osmosis membrane. The waste effluent can be directed back to the beginning of the main filtration loop by a check valve.

[0032] The clean water from the reverse osmosis membrane undergoes further treatment and testing. To this end, the clean water is directed through a flow meter, a heater, a temperature sensor, and a conductivity sensor. If the water being tested is determined to be acceptable for use in producing dialysate, a concentrated reagent is introduced into the clean water through a pair of pumps to produce the dialysate. The concentrated reagent can include one or more of the following: a bicarbonate solution, an acid solution, a lactate solution, and a salt solution. An additional conductivity sensor is provided to confirm that the appropriate amount of reagent is being introduced into the water.

[0033] Before the dialysate is sent to the hemodialysis machine, the dialysate now being produced is passed through an additional ultraviolet sterilizer to kill any remaining bacteria and through a sub-micron filter to remove any endotoxins that can remain from the dead bacteria. The sterilized dialysate is delivered through a fluid outlet of the dialysate generator to the hemodialysis machine. Preferably, the dialysate generator has multiple bypass flow paths and controllable valves to control the various functions of the dialysate generator.

[0034] In another embodiment of the hemodialysis system, one or more reservoirs are located in the dialysate generator rather than in the hemodialysis machine. For this embodiment, the one or more reservoirs are in the flow path of the dialysate generator to form a closed loop system for delivering dialysate from the one or more reservoirs to the hemodialysis machine and back to the reservoirs. More preferably, the dialysate generator has two (or more) reservoirs of dialysate that can be alternatively placed within the flow path of the dialysate generator. When one reservoir has contaminated dialysate, the other reservoir can be used to continue the dialysis treatment while the reservoir with the contaminated dialysate is emptied and refilled. Similar to the embodiment where the reservoirs are located within the hemodialysis machine, the reservoirs can be any size that the clinician needs to perform the appropriate hemodialysis treatment. However, it is preferred that the two reservoirs are the same size and small enough so that the dialyzer is easily portable. Acceptable reservoir capacities are 0.5 liters to 5.0 liters. A preferred reservoir stores about 2.0 liters of dialysate.

[0035] A hemodialysis machine and a dialysate generator are independent machines that can be connected or disconnected from each other. To this end, preferably, the hemodialysis machine includes a housing for enclosing and protecting various components that provide hemodialysis treatment. In addition, the housing of the hemodialysis machine includes electrical connectors and fluid connectors for connecting to the dialysate generator. Similarly, the dialysate generator includes a housing for enclosing and protecting various components that generate fresh dialysate. Also similar to the hemodialysis machine, the housing of the dialysate generator includes electrical connectors and fluid connectors for connecting to the hemodialysis machine. More specifically, in addition to the fluid connectors and fluid conduits that deliver fresh dialysate to the hemodialysis machine and receive used dialysate from the hemodialysis machine, the hemodialysis machine and the dialysate generator also include electrical wires and engageable (and disengageable) electrical terminals that connect all of the electrical and electromechanical components of the dialysate generator to the processor of the hemodialysis machine. These include all of the pumps, sensors, heaters, ultraviolet sterilizers, variable orifices, and valves of the dialysate generator, thereby enabling the processor of the hemodialysis machine to control the operation of the dialysate generator. Advantageously, mechanically and electrically connecting the dialysate generator to the hemodialysis machine enables the user of the hemodialysis system to control the operation of both the hemodialysis machine and the dialysate generator using only the user interface of the hemodialysis machine.

[0036] The hemodialysis machine housing and the dialysate generator housing can be configured innumerable shapes and sizes to physically couple together. However, in the preferred embodiment, the hemodialysis machine has a generally hexahedral shape and is sized and shaped like a medium-sized suitcase. Because it has a generally hexahedral shape, the housing of the hemodialysis machine has six sides and preferably includes generally parallel top and bottom sides, generally parallel left and right sides, and generally parallel front and back sides. Meanwhile, the preferred dialysate generator has a housing that is generally configured in an "L" shape, including a horizontally extending base unit configured to rest on a surface, and a vertically extending rear unit that extends vertically from the rear of the base unit. Preferably, the processor and pumps of the dialysate generator are located in its base unit, and the filter and concentrate reagents of the dialysate generator are located in the rear unit. In addition, it is preferred that the carbon filter and the reverse osmosis membrane are located in an elongated cylindrical container that is positioned vertically in the rear unit of the dialysate generator. Furthermore, it is preferred that the rear side of the rear unit has an openable rear panel that enables access to all of the disposable components (including the carbon filter, the reverse osmosis membrane, and the containers of concentrate reagents) so that they can be easily removed and replaced when exhausted. The dialysate reservoir can be located within the hemodialysis machine or within the housing of the dialysate generator.

[0037] Further, the hemodialysis machine housing and the dialysate generator housing are configured such that the hemodialysis machine can be engaged and rested on the base unit of the dialysate generator with the back side of the hemodialysis machine engaging the back unit of the dialysate generator to form a stable combination.

[0038] The hemodialysis system (including the hemodialysis machine and the dialysate generator) is portable, lightweight, easy to use, patient friendly, and can be used at home.

[0039] Further, the hemodialysis system provides a large amount of control and monitoring that previous hemodialysis systems have not provided, thereby providing enhanced patient safety.

[0040] Other features and advantages of the present application will be apparent to those skilled in the art upon reading the following detailed description of the application, taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 is a flow diagram illustrating a hemodialysis system including a hemodialysis machine.

[0042] Figure 2 is a flow diagram illustrating a dialysate generator checking its incoming water, where the thicker dashed line illustrates water that can be moved in the flow path;

[0043] Figure 3 is a flow diagram illustrating a dialysate generator producing dialysate, where the thicker dashed line illustrates water that can be moved in the flow path;

[0044] Figure 4 is a flow diagram illustrating a dialysate generator delivering dialysate to a hemodialysis machine, where the thicker dashed line illustrates water that can be moved in the flow path;

[0045] Figure 5 is a flow diagram illustrating a dialysate generator draining dialysate from a hemodialysis machine, where the thicker dashed line illustrates water that can be moved in the flow path;

[0046] Figure 6 is a flow diagram illustrating a dialysate generator flushing dialysate from a hemodialysis machine with fresh water, where the thicker dashed line illustrates water that can be moved in the flow path;

[0047] Figure 7 is a flow diagram illustrating a dialysate generator sterilizing itself with hot water, where the thicker dashed line illustrates water that can be moved in the flow path;

[0048] Figure 8 is a flow diagram illustrating a dialysate generator sterilizing a waste fluid path from a hemodialysis machine, where the thicker dashed line illustrates water that can be moved in the flow path;

[0049] Figure 9 is a flow chart illustrating the disinfection of one of the drain paths of the dialysate generator, where the thicker dashed line illustrates water that can be moved in the flow path;

[0050] Figure 10 is a flow chart illustrating the disinfection of one of the drain paths of the dialysate generator, where the thicker dashed line illustrates water that can be moved in the flow path;

[0051] Figure 11 is a front perspective view of a hemodialysis system;

[0052] Figure 12 is an exploded front perspective view of a hemodialysis system;

[0053] Figure 13 is an exploded rear perspective view of a hemodialysis system;

[0054] Figure 14 is a rear perspective view of a hemodialysis system;

[0055] Figure 15 is a front elevational view of a hemodialysis system;

[0056] Figure 16 is a rear elevational view of a hemodialysis system;

[0057] Figure 17 is a side elevational view of a hemodialysis system;

[0058] Figure 18 is a top plan view of a hemodialysis system; and

[0059] Figure 19 is a bottom plan view of a hemodialysis system. DETAILED DESCRIPTION

[0060] While the application is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the application to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the application as defined by the appended claims.

[0061] As shown in Figure 1 and Figures 11-19 the hemodialysis system includes a hemodialysis machine 100 and a dialysate generator 201 that are physically connectable and disconnectable from one another. With particular reference to Figure 12 and 13To connect the hemodialysis machine 100 and the dialysate generator 201, the hemodialysis machine 100 has an electrical connector 108 and fluid connectors 109 and 110, and the dialysate generator 201 has an electrical connector 325 and fluid connectors 321 and 323. The corresponding electrical and fluid connectors are positioned and configured to allow both fluid and electrical connections between the two machines. Advantageously, the electrical and fluid connectors are detachable, thereby allowing the dialysate generator to be separated from the hemodialysis machine 100.

[0062] Hemodialysis machine

[0063] like Figure 1 As best shown, the hemodialysis machine 100 includes a blood flow path 53 and a dialysate flow path 54. The blood flow path 53 includes an arterial blood line 1 for connecting to an artery of the patient to collect blood from the patient, and a venous blood line 14 for connecting to a vein of the patient to return blood to the patient. The arterial blood line 1 and the venous blood line 14 may be typical configurations known to those skilled in the art.

[0064] Blood flow path 53 delivers blood to the patient in a closed-loop system via arterial blood line 1 and venous blood line 14 for transporting blood from the patient through dialyzer 8 and back to the patient. Preferably, the hemodialysis machine includes a heparin supply source 6 and a heparin pump connected to blood flow path 1. The heparin pump delivers a small amount of heparin anticoagulant into the bloodstream to reduce the risk of blood clotting within the machine. The heparin pump can be in the form of a linearly actuated syringe pump, or it can be a bag connected to a small peristaltic pump or infusion pump.

[0065] The hemodialysis machine includes a dialyzer 8 in a dialysate flow path 54, the dialyzer having a construction and design known to those skilled in the art. Preferably, the dialyzer 8 includes a large number of hollow fibers forming a semipermeable membrane. Suitable dialyzers are available from Fresenius Medical Care, Baxter International, Nipro Medical, and other manufacturers of hollow fiber dialyzers. Both the blood flow path and the dialysate flow path pass through the dialyzer 8, which has an inlet for receiving dialysate, an outlet for discharging dialysate, an inlet for receiving blood from the patient, and an outlet for returning blood to the patient. Preferably, the dialysate flows in the opposite direction to the blood flowing through the dialyzer, wherein the dialysate flow path is separated from the blood flow path by a semipermeable membrane (not shown). Figures 1-6As shown in the middle and explained in more detail below, the dialysate flow path 54 conveys dialysate in a closed loop system, in which dialysate is pumped from a reservoir (17 or 20) to the dialyzer 8 and back to the reservoir (17 or 20). Both the blood flow path 53 and the dialysate flow path 54 pass through the dialyzer 8, but the flow paths are separated by the semi-permeable membrane of the dialyzer. The reservoirs 17 and 20 can be located within the hemodialysis machine 100, or the reservoirs 17 and 20 can be located outside of the hemodialysis machine, for example in a dialysate generator 201.

[0066] Preferably, the hemodialysis machine includes three main pumps (5, 26, and 33) for pumping blood and dialysate. For purposes herein, the term "pump" refers to both a pump actuator that moves fluid using suction or pressure, and to a pump motor that is used to mechanically move the actuator. Suitable pump actuators can include an impeller, a piston, a diaphragm, a cam of a cam pump, a screw of a screw pump, rollers of a peristaltic pump, or linearly moving fingers, or any other mechanical configuration for moving fluid, as can be determined by one skilled in the art. At the same time, a motor of a pump is an electromechanical device for moving the actuator. The motor can be connected to the pump actuator by a shaft or the like. In a preferred embodiment, dialysate and / or blood flows through a conventional flexible tube, and each pump actuator consists of a peristaltic pump mechanism, in which each pump actuator includes a rotor to which a plurality of cams compressing the flexible tube are attached in the form of "rollers," "shoes," "wipers," or "blades" to the outer circumference of the rotor. When the rotor is turned, the compressed portions of the tube are squeezed closed (or "occluded"), forcing fluid to be pumped through the tube. In addition, as the tube opens to its natural state after passing through the cams, it causes fluid to flow through the tube.

[0067] The first and second main pumps (26 and 33) are connected to the dialysate flow path for pumping dialysate through the dialysate flow path from the reservoir (17 or 20) to the dialyzer 8 and back to the reservoir (17 or 20). The first pump 26 is connected to the dialysate flow path "upstream" of the dialyzer 8 (meaning earlier in the flow path), while the second pump 33 is connected to the dialysate flow path "downstream" of the dialyzer 8 (meaning later in the flow path). At the same time, the third main pump 6 of the hemodialysis machine is connected to the blood flow path. The third pump 6 (also referred to as a blood pump) pumps blood from the patient through the arterial blood line, through the dialyzer 8, and through the venous blood line to return to the patient. It is preferred that the third pump 6 is connected to the blood flow path upstream of the dialyzer. The hemodialysis machine can contain more or less than three main pumps. For example, a single pump can be utilized to pump dialysate through the dialyzer 8. However, it is preferred that the hemodialysis machine contains two pumps, including the first pump 26 upstream of the dialyzer 8 and the second pump 33 downstream of the dialyzer 8.

[0068] In Figure 1In one embodiment shown, the hemodialysis machine 100 includes two or more reservoirs (17 and 20) for storing dialysate. Two reservoirs (17 and 20) may be simultaneously connected to the dialysate flow path 54 to form a large dialysate source. However, this is not considered preferred. Instead, the hemodialysis system includes a valve assembly 21 for introducing either, but not both, of the two reservoirs (17 or 20) into the dialysate flow path 54 to form a closed-loop system for delivering dialysate from one of the two reservoirs to the dialyzer and back to that reservoir. After the dialysate in the first reservoir 17 has been used, is no longer sufficiently clean, or does not have the appropriate chemistry, the valve 21 of the hemodialysis machine is controlled to remove the first reservoir 17 from the dialysate flow path and replace it with a second reservoir 20 containing fresh dialysate. Thus, when one reservoir has contaminated dialysate and needs to be emptied and refilled with freshly generated dialysate 75, the other reservoir can be used to continue dialysis treatment.

[0069] In this way, the hemodialysis machine can switch between each reservoir 17 and 20 multiple times during treatment. Furthermore, the presence of two reservoirs, compared to a single reservoir, allows for flow measurement for pump calibration or ultrafiltration measurements, while isolating the other reservoir when it is drained or filled. Although the reservoirs can be of any size required by clinicians to perform appropriate hemodialysis treatment, preferred reservoirs have a volume between 0.5 liters and 5.0 liters.

[0070] for Figures 1-9 In the embodiment shown, the hemodialysis system includes a discharge flow path 55 to dispose of waste dialysate from reservoirs (17 and 20). Figures 1-4 In the illustrated embodiment, the discharge flow path 55 is connected to two reservoirs (17 and 20). Waste dialysate can be discharged via discharge flow path 5 by gravity feed, or the hemodialysis system may include any type of pump that can be selected by those skilled in the art to pump the used dialysate to be discarded.

[0071] Still referencing Figure 1 The hemodialysis machine preferably has a heater 23 thermally connected to the dialysate flow path or reservoir for heating the dialysate to the required temperature. For example, in Figure 1 In the illustrated embodiment, a single heater 23 is thermally coupled to the dialysate flow path downstream of both reservoirs (17 and 20). However, the hemodialysis machine may include additional heaters, and one or more heaters may be located in different positions. For example, in an alternative embodiment, the hemodialysis system includes two heaters, with each heater thermally coupled to each reservoir. The one or more heaters are preferably electrically activated and include resistors that generate heat as current flows through them.

[0072] Furthermore, the hemodialysis machine 100 has various sensors for monitoring the hemodialysis, in particular the blood flow path 53 and the dialysate flow path 54. To this end, the hemodialysis machine 100 preferably has one or more flow sensors 25 connected to the dialysate flow path for monitoring the fluid flow (volume and / or velocity) within the dialysate flow path 54. Furthermore, it is preferred that the hemodialysis machine comprises one or more pressure or occlusion sensors (9 and 27) for detecting the pressure within the dialysate flow path. Preferably, the hemodialysis machine also has one or more sensors for measuring the pressure (4 and 7) and / or the fluid flow 11 within the blood flow path.

[0073] Preferably, the hemodialysis machine comprises temperature sensors (22, 24 and 28) for measuring the temperature of the dialysate in the entire dialysate flow path. One of the temperature sensors, for example the temperature sensor 24, can be a conductivity / temperature sensor. Furthermore, the hemodialysis system has a liquid level sensor for detecting the liquid level in the reservoirs (17 and 20). The preferred liquid level sensor can comprise a capacitive liquid level sensor, an ultrasonic liquid level sensor or a load cell. In a preferred embodiment, the liquid level of each reservoir is measured by a pair of redundant load cells 15, 16, 18 and 19. Furthermore, it is preferred that the hemodialysis machine comprises a blood leak detector 31 which monitors the flow of dialysate through the dialysate flow path and detects whether blood has inappropriately diffused through the semi-permeable membrane of the dialyzer into the dialysate flow path.

[0074] Preferably, the hemodialysis machine further comprises a first pinch valve 2 connected to the arterial blood line 1 for selectively allowing or impeding the flow of blood through the arterial blood line and a second pinch valve 13 connected to the venous blood line 14 for selectively allowing or impeding the flow of blood through the venous blood line. The pinch valves are arranged to pinch the arterial blood line 1 and the venous blood line 14 to prevent blood from flowing back to the patient in case any of the sensors has detected an unsafe condition. Providing a further additional safety function, the hemodialysis machine comprises blood line bubble sensors (3 and 12) to detect whether a bubble is travelling back along the arterial line (blood leak sensor 3) or the venous line (blood leak sensor 12). Furthermore, the blood flow path 53 can comprise a bubble trap 10 having a pressurized air pocket within a plastic housing. Bubbles rise to the top of the bubble trap while blood continues to flow to the lower outlet of the trap. This component reduces the risk of bubbles entering the blood of the patient.

[0075] Preferably, the fluid level in the bubble trap is measured by one or more level sensors 78. Furthermore, in a preferred embodiment, the hemodialysis machine 100 comprises means for increasing or decreasing the pressure within the bubble trap 10. As Figure 1As shown, the preferred hemodialysis machine 100 includes an air release flow path that includes a transducer protector 79, a pressure sensor 80, and a variable air release valve 81. The transducer protector 79 allows air to pass but not liquid to prevent blood from being released through the air release flow path. The variable air release valve 81 can be opened or closed. When closed, blood moving through the blood flow path 53 will cause an increase in pressure within the blood flow path 53 and the bubble trap 10. By opening the air release valve 81 to release air through the air release flow path, this pressure can be controllably reduced (to ambient pressure). By adjusting the valve between a fully open state and a fully closed state, the hemodialysis machine can control and maintain the fluid pressure within the blood flow path 53.

[0076] To control the flow and direction of blood and dialysate through the hemodialysis system, the hemodialysis system includes various fluid valves for controlling the flow of fluid through various flow paths of the hemodialysis system. The various valves include pinch valves and two-way valves that must be opened or closed, and three-way valves that divert dialysate through the desired flow paths as intended. In addition to the valves described above, the hemodialysis system includes a three-way valve 21 at the outlet of the reservoirs that determines from which reservoir (17 or 20) dialysate is passed through the dialyzer 8. An additional three-way valve 42 determines to which reservoir used dialysate is sent. Finally, two-way valves 51 and 52, which can be pinch valves, are located at the inlet of the reservoirs to allow or block the supply of fresh dialysate to the reservoirs (17 and 20). Of course, one skilled in the art can determine that alternative valves can be employed, and the present invention is not intended to be limited to the particular two-way or three-way valves that have been identified.

[0077] Although not shown in the figures, the hemodialysis machine 100 includes a processor and a user interface. The processor contains specialized electronics for controlling the hemodialysis system, including power management circuitry connected to the pump motors, sensors, valves, and heaters, for controlling the normal operation of the hemodialysis machine. The processor monitors each of the various sensors to ensure that the hemodialysis treatment is proceeding according to the preprogrammed procedures input by medical personnel into the user interface. The processor can be a general purpose computer or microprocessor, including hardware and software that one skilled in the art can determine, to monitor the various sensors and provide automatic or directed control over the heaters, pumps, and pinch valves. The processor can be located within the electronics of a circuit board or within aggregate processing of multiple circuit boards.

[0078] Also not shown, the hemodialysis machine includes a power supply for providing power to the processor, the user interface 111, the pump motors, the valves, and the sensors. The processor is connected by conventional circuitry to the dialysis machine sensors (including reservoir level sensors (15 and 18), blood leak sensors 31, pressure and flow sensors (4, 7, 9, 11, 25, and 27), temperature / conductivity sensors (22, 24, and 28), blood line bubble sensors (3 and 12)), the pumps (5, 6, 26, 33, 40, 44, 47, and 49), and the pinch valves (2 and 13).

[0079] In operation, the processor is electrically connected to the first, second, and third master pumps (5, 26, and 33) for controlling the activation and rotational speed of the pump motors, and in turn, the pump actuators, and in turn, the pressure and fluid velocity of the blood through the blood flow path and the pressure and fluid velocity of the dialysate through the dialysate flow path. By independently controlling the operation of the dialysate pumps 26 and 33, the processor can maintain, increase, or decrease the pressure and / or fluid flow within the dialysate flow path within the dialyzer. Further, by independently controlling all three pumps, the processor can control the pressure differential across the semi-permeable membrane of the dialyzer to maintain a predetermined pressure differential (zero, positive, or negative), or to maintain a predetermined pressure range. For example, most hemodialysis is performed with a pressure differential across the semi-permeable membrane of zero or near zero, for which the processor can monitor and control the pumps to maintain this desired zero or near zero pressure differential. Alternatively, the processor can monitor the pressure sensors and control the pump motors, and in turn, the pump actuators, to increase and maintain a positive pressure in the blood flow path within the dialyzer relative to the pressure of the dialysate flow path within the dialyzer. Advantageously, this pressure differential can be influenced by the processor to provide ultrafiltration and the transfer of free water and dissolved solutes from the blood to the dialysate.

[0080] In the preferred embodiment, the processor monitors the blood flow sensor 11 to control the blood pump flow. It uses the dialysate flow sensor 25 to control the dialysate flow from the upstream dialysate pump. The processor then uses the reservoir level sensors (15, 16, 18, and 19) to control the flow from the downstream dialysate pump 33. The change in level (or volume) in the dialysate reservoir is the same as the change in volume of the patient. By monitoring and controlling the level in the reservoir, positive, negative, or zero ultrafiltration can be achieved.

[0081] In addition, the processor monitors all of the various sensors to ensure that the hemodialysis machine is operating effectively and safely, and in the event that an unsafe or unassigned condition is detected, the processor corrects the deficiency or stops further hemodialysis treatment. For example, if the venous blood line pressure sensor 9 indicates an unsafe pressure or the air bubble sensor 12 detects an air bubble in the venous blood line, the processor issues an alarm, deactivates the pump, and closes the pinch valve to prevent further blood flow back to the patient. Similarly, if the blood leak sensor 31 detects that blood has leaked past the semi-permeable membrane of the dialyzer, the processor issues an alarm and stops further hemodialysis treatment.

[0082] The user interface of the dialysis machine can include a keyboard or touchscreen 111 for enabling a patient or medical personnel to input commands regarding treatment or for enabling a patient or medical personnel to monitor the performance of the hemodialysis machine. In addition, the processor can include a Wi-Fi or Bluetooth connection for transmitting information or control to a remote location.

[0083] The various components of the preferred hemodialysis machine will be identified hereinafter with reference to the numbers corresponding to the components shown in the figures.

[0084]

[0085]

[0086]

[0087] Hemodialysis treatment options

[0088] The hemodialysis system provides increased flexibility in treatment options depending on the required frequency of dialysis, the characteristics of the patient, the availability of dialysate or water, and the required portability of the dialysis machine. For all treatments, the blood flow path 53 transports blood to the patient in a closed loop system through connections to the arterial blood line 1 and the venous blood line 14 for transporting blood from the patient to the dialyzer and back to the patient.

[0089] Reference Figure 1 A first method of providing hemodialysis includes the step of introducing dialysate to the hemodialysis machine from a source of water 46 (such as water supplied by reverse osmosis (RO)) through a fresh dialysate flow path 56. The mixed dialysate is then introduced to the reservoirs 17 and 20. For this treatment, the dialysate from the first reservoir is recirculated through the dialyzer 8 back to the same reservoir through the bypass path 35. When the volume of the reservoir has been recirculated once, the reservoir is emptied through the drain flow path 55 and the reservoir is refilled through the fresh dialysate flow path 56.

[0090] Meanwhile, while the first reservoir is emptied and refilled, hemodialysis treatment continues using the second reservoir (17 or 20). Once the processor determines that all dialysate has been recirculated once, or determines that the dialysate is contaminated, the processor switches all relevant valves (21, 42, 43, 51, and 52) to remove the first reservoir 20 from the patient's treatment and inserts the second reservoir 17 into the dialysate flow path 54. Dialysate from the second reservoir 17 is recirculated through the dialyzer 8 via the bypass path 35 and returned to the same reservoir 17. This back-and-forth switching between reservoirs 17 and 20 continues until the dialysis treatment is complete. This operation is similar to but different from a conventional single-pass system because an adsorption filter is not used.

[0091] like Figure 4 As shown, once the processor determines that it is no longer suitable to continue using reservoir 17 for dialysis treatment, the processor switches various valve assemblies (21, 42, 43, 51, and 52) to remove reservoir 17 from dialysate flow path 54 and instead insert reservoir 20 into the dialysate flow path for dialysis treatment. Clean dialysate is recirculated back to the same reservoir 20 via dialyzer 8. Similarly, the processor determines whether this recirculation continues using reservoir 20 until switching back to reservoir 17, or until dialysis treatment is completed. While dialysis treatment continues using reservoir 20, contaminated fluid in reservoir 17 is drained through the drain flow path. Reservoir 17 is then refilled using fresh dialysate flow path 56. Similar to other treatment methods, this back-and-forth switching between reservoirs 17 and 20 continues until dialysis treatment is completed.

[0092] In another additional embodiment, during treatment, dialysate 75 from the first reservoir is recirculated through dialyzer 8 and directed back to the same reservoir. Similar to the previous embodiment, dialysis treatment is performed while switching back and forth between reservoirs 17 and 20. When dialysis treatment uses clean dialysate from reservoir 17, various valve assemblies (21, 42, 43, 51, and 52) are switched to insert the second reservoir 20 into closed-loop filtration flow paths 55 and 56. Contaminated water is discharged from reservoir 20.

[0093] refer to Figure 1 The processor continues to monitor the outputs of various sensors, including those within the dialysate flow path 54. Once the water in reservoir 17 becomes contaminated, it is removed from the dialysate flow path, and reservoir 20 is replaced in its place by switching all relevant valve assemblies (21, 42, 43, 51, and 52) back into place. Dialysate 75 from the second reservoir 20 is recirculated through dialyzer 8 in the closed-loop dialysate flow path 54 and directed back to the same reservoir. Simultaneously, the now-contaminated water in reservoir 17 is drained, and fresh dialysate is introduced into reservoir 17.

[0094] Dialysate generator

[0095] Referring to Figures 1-10 The preferred dialysate generator 201 includes an inlet 205 for introducing water (e.g., tap water) into the various fluid flow paths of the system. The inlet flow path 203 includes a pressure regulator 207, a one-way valve 209, a first carbon and sediment filter 211, a sample port 213, and a second carbon filter 215. The pressure regulator 207 ensures that the water pressure is not too high for the dialysate generator. The first carbon and sediment filter 211 removes sediment, chlorine, and chloramines, while the second carbon filter 215 serves as a backup to the upstream filter 211. The filtered water is then directed to a second fluid path that includes an ultraviolet (UV) sterilizer 221, a water descaler 223, a temperature sensor 225, a pressure sensor 227, a conductivity sensor 229, a pump 231 (preferably a diaphragm pump), and an additional pressure sensor 233. The ultraviolet (UV) sterilizer kills any bacteria that enter the system. The descaler removes dissolved calcium from the water. The temperature sensor 225, pressure sensor 227, and conductivity sensor 229 ensure that the incoming water meets specific requirements for temperature (TPi), pressure (PPi), and conductivity (CPi). After passing through the pressure sensor 233, the water flows to a reverse osmosis membrane 235.

[0096] The ultraviolet sterilizer 221 can include any light source that produces ultraviolet light and is capable of killing bacteria. In a preferred embodiment, the ultraviolet sterilizer 221 is a short fluid conduit that contains a UV-producing LED with strong short wavelength (250-280 nm) radiation. Suitable fluid conduits containing LEDs can be purchased from Acuva Technologies, Inc. and Crystal IS, Inc. The descaler 223 can be any configuration for reducing or eliminating the buildup of calcium scale caused by dissolved calcium carbonate or other calcium salts in the water. Preferably, the descaler does not use the introduction of chemicals to provide water softening. Rather, the preferred descaler 223 is a mechanical device that provides a drop in water pressure and a magnetic field provided by a stationary magnet to convert the dissolved calcium salts into calcium crystals. The calcium crystals can then be removed from the water by a filter located within the descaler, or more preferably by a separate downstream filter within the dialysate generator. A suitable descaler is sold by Dime Water, Inc. of Vista, California, and is described in U.S. Patent No. 6,221,245, which is incorporated by reference in its entirety.

[0097] The reverse osmosis membrane 235 outputs a "clean water" and a "waste" effluent. The waste effluent from the reverse osmosis membrane is split by a bypass valve 237, some of which is discarded and another portion of which is sent to a pair of parallel fluid orifices 239 and 241 that controllably restrict the flow of water and create back pressure in the reverse osmosis membrane. These orifices 239 are configured to balance the flow through and past the membrane. Some of the water that flows through the reverse osmosis membrane 235 must be discarded through a three-way valve 243. Alternatively, some of the water is recirculated through a three-way valve 245. A check valve 219 ensures that the recirculated water enters the flow path with the incoming water and vice versa.

[0098] If the fluid is pushed through the reverse osmosis membrane 235, the clean water produced thereby is subjected to further processing and testing. To this end, the fluid flow is measured by a flow meter 251. The water is heated to body temperature by a heater 253 and a temperature sensor 255 is provided to control the heater 253. The conductivity of the water is measured by a conductivity sensor 257 to ensure that the reverse osmosis membrane has sufficiently cleaned the water. If the tested water is determined to be acceptable, two chemical concentrates 259 and 267 are added to the water in order to prepare the final dialysate composition. The concentrated reagents are introduced into the clean water by a pair of pumps 261 and 269 to produce the dialysate. Preferably, the pumps 261 and 269 are piston pumps that meter the addition of the chemical concentrates into the pure water stream. Likewise, the conductivity of the water is measured by conductivity sensors 265 and 273 to ensure that the reverse osmosis membrane 235 has sufficiently cleaned the water and to confirm that the appropriate amounts of chemical reagents 259 and 267 have been introduced into the water. Finally, the dialysate is delivered through another ultraviolet (UV) sterilizer 275 to kill any remaining bacteria and then a sub-micron ultrafilter 277 captures any endotoxins remaining in the dead bacteria. The sterile dialysate is delivered from the fluid outlet of the dialysate generator to the hemodialysis machine to the fresh dialysate flow path 56 of the hemodialysis machine.

[0099] Preferably, the dialysate generator 201 has a plurality of bypass flow paths 289, controllable valves 209, 237, 243, 245, and 279, and pumps 231, 261, 267, and 285 to control the various operations of the machine. For example, as shown in FIG. 2, preferably the dialysate generator 201 includes a pump 285, a pressure sensor 283, and a check valve 281 connected to the drain flow path 55 of the hemodialysis machine for controlling the drainage of spent dialysate from the reservoirs 17 or 20. The reservoirs 17 and 20 can be located in the hemodialysis machine 100 or the dialysate generator 201. However, in the preferred embodiment, the reservoirs 17 and 20 are located in the dialysate generator 201. Figures 1-10 Figure 4 and Figure 5 ​In the preferred embodiment shown, reservoirs 17 and 20 are located in dialysate generator 201, as are control valves 21, 42, 43, and 51. In addition, preferably, dialysate generator 201 has an additional three-way valve 279 that routes dialysate from fresh dialysate flow path 56 through three-way valve 245 back to drain line 249. Additionally, with reference to Figures 1 to 10 Preferably, dialysate generator 201 has a bypass flow path 289 that connects fresh dialysate flow path 56 of the hemodialysis machine with spent dialysate flow path 55 of the hemodialysis machine.

[0100] The hemodialysis system includes at least one processor that contains power management and control circuitry connected to the pump motors, valves, and sensors for controlling the proper operation of the hemodialysis system, including the hemodialysis machine and the dialysate generator. The preferred hemodialysis system includes two processors, with the first processor located in the hemodialysis machine 100 and the second processor located in the dialysate generator 201. However, it is preferred that the main control processor for the entire hemodialysis system is located in the hemodialysis machine 100, and as described below, preferably the dialysate generator 201 is electrically connected to and controlled by this main processor within the hemodialysis machine 100. However, it is preferred that the dialysate generator 201 includes a secondary processor for controlling and cycling through the various cleaning and disinfection modes, but preferably the dialysate generator includes only a single switch button 327. The preferred dialysate generator 201 does not include any additional buttons, knobs, switches, or other control interfaces. Rather, preferably the dialysate generator 201 is controlled only through the user interface 111 of the hemodialysis machine, or in the case where the dialysate generator is disconnected from the hemodialysis machine, the only function of the dialysate generator is to cycle through the cleaning and disinfection modes. Preferably, the dialysate generator is provided with one or more status or warning lights that can indicate a fault condition or the need to replace a disposable item such as a filter or consumable concentrate. In the preferred embodiment, the dialysate generator 201 includes only a single LED light 329 that provides three different colors to indicate power on, cleaning mode, or an error detected.

[0101] Preferably, the hemodialysis machine 100 is capable of operating without the dialysate generator 201, for example by obtaining dialysate from a source other than the dialysate generator described herein. However, since the preferred dialysate generator 201 does not have a user interface, other than operating in the cleaning mode, the preferred dialysate generator is configured to operate only with the hemodialysis machine 100 described herein.

[0102] Hereinafter, the various components of the preferred dialysate generator will be identified with the numbers corresponding to the components shown in the figures.

[0103]

[0104]

[0105]

[0106] Dialysate generator operation

[0107] The dialysate generator can perform various operations. Figure 2 In the first mode shown, the feed water source is inspected to determine if it meets quality requirements and requirements related to temperature, pressure, and conductivity. The product water is heated to the target dialysate temperature, and the water is monitored by various sensors. This mode requires the activation of valves, heaters, pumps, and ultraviolet sterilizers as described below.

[0108]

[0109]

[0110] exist Figure 2 In the second mode shown, the dialysate generator 201 produces clean water but not dialysate, used for monitoring the reverse osmosis product water. It also heats the water produced by reverse osmosis to the target dialysate treatment temperature and tests the water's temperature compliance. This mode requires activation valves, heaters, pumps, and UV sterilizers as described below.

[0111] Actuator figure number Preferred actuator type Actuator state 209-VPi One-way Open 237-VBf One-way Close 279-VPo Three-way Recycle 245-V5 Three-way To drain 243-V8 Three-way To drain 253-HP Heater On 231-ROP Diaphragm On 269-PCP1 Piston Idle 261-PCP2 Piston Idle 285-DRP Gear Idle 221-UVi UV reactor On 275-UVo UV reactor On

[0112] exist Figure 3 In the third mode shown, dialysate generator 201 generates dialysate. A chemical concentrate is added to the clean water produced by reverse osmosis to produce the correct dialysate composition. However, the dialysate is not supplied to the hemodialysis machine 100. Instead, the dialysate is tested to confirm that it meets quality requirements. This mode requires the activation of valves, heaters, pumps, and ultraviolet sterilizers as described below.

[0113] Actuator figure number Preferred actuator type Actuator state 209-VPi One-way Open 237-VBf One-way Close 279-VPo Three-way Recycle 245-V5 Three-way To drain 243-V8 Three-way To drain 253-HP Heater On 231-ROP Diaphragm On 269-PCP1 Piston On 261-PCP2 Piston On 285-DRP Gear Idle 221-UVi UV reactor On 275-UVo UV reactor On

[0114] exist Figure 4 In the fourth mode shown, dialysate generator 201 generates dialysate and delivers it to the hemodialysis machine. The hemodialysis machine then transfers the generated dialysate to one of the reservoirs (17 or 20). This mode requires activation valves, heaters, pumps, and ultraviolet sterilizers as described below.

[0115]

[0116]

[0117] exist Figure 5In the fifth mode shown, dialysate generator 201 discharges waste dialysate from one of the hemodialysis reservoirs (17 or 20). No new dialysate is generated during the discharge, and the addition of additional chemical concentrates is stopped. The hemodialysis machine determines which reservoir to discharge, such as... Figure 5 The reservoir to be drained is reservoir 20. This mode requires the activation of the valve, heater, pump, and ultraviolet sterilizer as described below.

[0118]

[0119]

[0120] exist Figure 6 In the sixth mode shown, the dialysate generator 201 flushes the dialysate from its fluid path. This mode requires the activation valve, heater, pump, and UV sterilizer as described below.

[0121] Actuator figure number Preferred actuator type Actuator state 209-VPi One-way Open 237-VBf One-way Close 279-VPo Three-way Recycle 245-V5 Three-way To drain 243-V8 Three-way To drain 253-HP Heater On 231-ROP Diaphragm On 269-PCP1 Piston Idle 261-PCP2 Piston Idle 285-DRP Gear Idle 221-UVi UV reactor On 275-UVo UV reactor On

[0122] In the additional mode, dialysate generator 201 sterilizes itself. Sterilization activates heater 253 to heat the water in the system to 85°C. Water is recirculated through various flow paths in the system. The different paths alternate and balance, ensuring uniform heating throughout the system. Sometimes, liquid is diverted to the drain to sterilize the line leading to the drain. Fresh fluid is introduced into the system as fluid is diverted to the drain. During sterilization, valve 237-VBf is open to prevent high pressure across the reverse osmosis membrane.

[0123] exist Figure 7 In the first disinfection mode shown, hot water is recirculated throughout its entire fluid path to disinfect the system. This mode requires the activation of valves, heaters, pumps, and UV sterilizers as described below.

[0124] Actuator figure number Preferred actuator type Actuator state 209-VPi One-way Open 237-VBf One-way Open 279-VPo Three-way Recycle 245-V5 Three-way Recycle 243-V8 Three-way Recycle 253-HP Heater On 231-ROP Diaphragm On 269-PCP1 Piston On 261-PCP2 Piston On 285-DRP Gear Idle 221-UVi UV reactor Off 275-UVo UV reactor Off

[0125] In the second disinfection mode, the dialysate generator 201 disinfects the "waste" fluid path by recirculating hot water through a selected path, such as... Figure 8 As shown in the diagram. This mode requires the activation of the valve, heater, pump, and UV sterilizer as described below.

[0126]

[0127]

[0128] In the third disinfection mode, the dialysate generator 201 disinfects the "discharge" path from valve 245 by recirculating hot water through a selected path, such as... Figure 9 As shown in the image.

[0129] This mode requires activation of the valves, heaters, pumps, and UV sterilizers as described below.

[0130]

[0131]

[0132] In the fourth disinfection mode, the dialysate generator 201 disinfects the "drain" path leading from the valve 243 by recirculating hot water through the selected path, as shown in Figure 10

[0133] This mode requires activation of the valves, heaters, pumps, and UV sterilizers as described below.

[0134] Actuator figure number Preferred actuator type Actuator state 209-VPi One-way Open 237-VBf One-way Open 279-VPo Three-way Recycle 245-V5 Three-way Recycle 243-V8 Three-way To drain 253-HP Heater On 231-ROP Diaphragm On 269-PCP1 Piston On 261-PCP2 Piston On 285-DRP Gear Idle 221-UVi UV reactor Off 275-UVo UV reactor Off

[0135] Hemodialysis machine and dialysate generator combination

[0136] As shown in Figure 1 , 4 , 5, and 11-19, the hemodialysis machine 100 and the dialysate generator 201 are independent machines that can be connected or disconnected from one another. To this end, the hemodialysis machine includes a housing 101 for enclosing and protecting the various components that provide hemodialysis treatment. The hemodialysis machine housing 101 can be configured in countless shapes and sizes to physically engage the dialysate generator 201. However, in the preferred embodiment, the hemodialysis machine has a generally hexahedral shape, substantially comprising a top side 102, a bottom side 103, a left side 104, a right side 105, a front side 106, and a back side 107. Further, the hemodialysis machine 100 includes one or more electrical connectors 108 for transmitting and receiving electrical signals (and optionally electrical power) between the hemodialysis machine 100 and the dialysate generator. Further, as shown in Figure 1 , 4 , 5, and 13, the hemodialysis machine 100 includes at least one fluid connector 109 for receiving clean dialysate from the dialysate generator 201, and at least one fluid connector 110 for expelling used dialysate to the dialysate generator. Preferably, the hemodialysis machine includes a touch screen 111 integrated into the machine housing 101 or hingedly secured to the housing 101.

[0137] ​Similarly, the dialysate generator 201 includes a housing 301 for enclosing and protecting the various components that generate fresh dialysate. The preferred dialysate generator 201 has a housing 301 that has a generally "L" shaped configuration including a horizontally extending base unit 303 and a vertically extending rear unit 305 that extends vertically from the rear of the base unit 303. This configuration provides a housing 301 for the dialysate generator that has a top 307, a bottom 309, a left side 311, a right side 313, a front side 315, and a rear side 317. In addition, the horizontally extending base unit 303 provides a resting surface 319 on which the hemodialysis machine 100 rests when the hemodialysis machine is mated with the dialysate generator. Preferably, the processor and pumps of the dialysate generator are located in the hemodialysis base unit 100 thereof, and the filters and concentrate reagents of the dialysate generator are located in the dialysate generator rear unit 201. These chemical reagents can include the six (6) conventional electrolytes: sodium (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), chloride (Cl-), and bicarbonate, as well as glucose and / or dextrose. The reservoirs 17 and 20 can be located in the hemodialysis machine (as shown in Figure 1 the rear side 317 of the rear unit preferably has an openable rear panel 318 that provides access to all of the disposable components, including the carbon filter 211, the secondary filter 215, the reverse osmosis membrane 235, and the reservoirs 259 and 267 of concentrate reagents. The openable rear panel 318 can be completely removed or folded back on hinges so that the disposable components can be easily removed and replaced when spent. Figure 13 the rear side 317 of the rear unit preferably has an openable rear panel 318 that provides access to all of the disposable components, including the carbon filter 211, the secondary filter 215, the reverse osmosis membrane 235, and the reservoirs 259 and 267 of concentrate reagents. The openable rear panel 318 can be completely removed or folded back on hinges so that the disposable components can be easily removed and replaced when spent.

[0138] The dialysate generator 201 includes one or more electrical connectors 325 that are configured and positioned on the housing 301 of the dialysate generator for mating with the electrical connectors 108 of the hemodialysis machine. In addition, the dialysate generator 201 includes a first fluid connector 321 that is positioned through the housing of the dialysate generator for providing clean dialysate to the fluid connector 109 of the hemodialysis machine, and a second fluid connector 323 that is positioned through the housing 301 of the dialysate generator for receiving spent dialysate from the fluid connector 110 of the hemodialysis machine.

[0139] Finally, with regard to the example embodiments of the present application shown and described herein, it should be appreciated that a hemodialysis system is disclosed. The principles of the present application can be implemented in a variety of configurations other than those shown and described, and it is understood that the present application is not limited to any particular example embodiment, but is broadly directed to hemodialysis systems and can take a variety of forms without departing from the spirit and scope of the present application. Those skilled in the art will also appreciate that the present application is not limited to the specific geometric configurations and materials of construction disclosed, but other functionally equivalent structures or materials now known or later developed can be used without departing from the spirit and scope of the present application. Moreover, the various features of each of the embodiments described above can be combined in any logical manner and are intended to be included within the scope of the present application.

[0140] Groupings of alternative embodiments, elements or steps are not to be construed as limitations. Each member of a group can be referred to individually or in any combination with other members of the group or other steps. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and / or patentability. When any such inclusion or deletion occurs, the specification is to be construed as if such change had been made herein expressly.

[0141] Unless otherwise indicated, all numbers expressing quantities of components, items, amounts of parameters, properties, terms in the specification and claims are to be understood as approximations based on the best of available data and intended to convey within a range, precision to the degree reasonably required in light of the nature of the quantity. As used herein, the term "about" when used in relation to a quantity is inclusive of the stated value and the range of values plus or minus ten percent from the stated value. Thus, unless otherwise stated, the numerical parameters listed in the specification and attached claims are approximations that can vary depending on the requirements of the particular application. At least, each numerical parameter recited in the specification and claims should be interpreted, not as the numerical limitation in every instance, but rather as the approximation within a range, based on the number of reported significant digits and standard rounding approaches. Notwithstanding that the numerical ranges and values setting forth the broad scope of the application are approximations, the numerical ranges and values set forth in the specific examples are reported as precisely as possible. Any numerical range or value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. The numerical ranges and values reported herein are used to enable a person of ordinary skill in the art to construct a composition that falls within the ranges claimed. The numerical ranges and values are approximations that can vary as appropriate. The endpoints of the ranges of values are provided as a separate matter from the predictive values within the ranges. Whenever a numerical range is indicated, it is meant to include all cited numeral values within the indicated ranges. The phrases "about," "substantially," "approximately," and variations thereof, as used herein, refer to quantities, dimensions, values, steps, or other characteristics that are acceptable at the highest level of precision prior to the applicable industrial, regulatory, or safety standards, whether or not particularly specified or preferred. The use of "about" or "approximate" should be considered motivated by a reasonable amount of experimentation, whether or not specifically stated.

[0142] The use of the terms "a" and "an" and "the" and similar referents in the context of describing the application (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate the application and does not pose a limitation on the scope of the application otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the application.

[0143] The specific embodiments disclosed herein can be further limited by the terms of the claims. The transitional phrase "consisting of" as used in the claims is intended to have its plain and ordinary meaning as ascribed to it by the courts. The transitional phrase "consisting of" excludes any element, step, or ingredient not specified in the claims. The transitional phrase "consisting essentially of" limits the scope of a claim to the specified materials or steps and to materials and steps that do not materially affect the basic and novel characteristic(s). Embodiments of the application as so claimed are inherently or expressly described and enabled herein.

[0144] It should be understood that the logical code, programs, modules, processes, methods, and the order of execution of the respective elements of each method are purely exemplary. Depending on the implementation, they can be executed in any order or in parallel, unless otherwise specified in the present disclosure. Furthermore, the logical code does not involve or be limited to any particular programming language and can include one or more modules executed on one or more processors in a distributed, non-distributed, or multi-processing environment.

[0145] While several particular forms of the application have been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the application. Accordingly, the application is not to be limited except as by the appended claims.

Claims

1. A hemodialysis system comprising: a hemodialysis machine comprising: a dialyzer; a blood flow path that conveys blood through the dialyzer, the blood flow path including an arterial blood line connected to an artery of a patient and a venous blood line connected to a vein of the patient; a dialysate flow path isolated from the blood flow path, the dialysate flow path conveying dialysate through the dialyzer, the dialysate flow path including a dialysate flow path inlet that receives fresh dialysate and a dialysate flow path outlet that expels used dialysate; a blood pump that pumps blood through the blood flow path; a dialysate pump that pumps dialysate through the dialysate flow path; a main processor connected to the blood pump and dialysate pump; a user interface connected to the main processor; a hemodialysis machine electrical terminal electrically connected to the main processor; a hemodialysis machine housing, wherein the dialysate pump, blood pump, and main processor are located within the hemodialysis machine housing; and the user interface is affixed to the hemodialysis machine housing; the hemodialysis system further comprising a dialysate generation machine comprising: a dialysate generator flow path including a dialysate generator outlet connected to the dialysate flow path inlet and a dialysate generator inlet connected to the dialysate flow path outlet; a water source connected to the dialysate generator flow path; a water purification system connected to the dialysate generator flow path and that purifies water; a source of chemical reagents connected to the dialysate generator flow path, the chemical reagents forming dialysate when mixed with the water; a first reservoir for storing dialysate and having a volume between 0.5 liters and 5.0 liters, the first reservoir being in the dialysate flow path to store dialysate and to supply dialysate to the dialyzer; at least one chemical reagent pump that controls the flow of the chemical reagents into the dialysate generator flow path, the chemical reagents then being mixed with the water to form dialysate; at least one dialysate generator pump that controls the flow of dialysate through the dialysate generator flow path to the dialysate flow path inlet; a dialysate generator electrical terminal electrically connected to the at least one chemical reagent pump and the at least one dialysate generator pump; and a dialysate generator housing, wherein the water source, water purification system, source of chemical reagents, first reservoir, at least one chemical reagent pump, and at least one dialysate generator pump are located within the dialysate generator housing; and the hemodialysis machine and the dialysate generation machine are mechanically and electrically connectable and disconnectable, wherein the dialysate flow path inlet is connectable and disconnectable with the dialysate generator outlet, the dialysate flow path outlet is connectable and disconnectable with the dialysate generator inlet, and the hemodialysis machine electrical terminal is electrically connectable and disconnectable with the dialysate generator electrical terminal. The dialysate flow path is connected to the dialysate generator flow path to form a closed loop system, wherein when the hemodialysis machine is connected to the dialysate generator, the first reservoir supplies dialysate to the dialyzer, and the dialyzer sends used dialysate back to the first reservoir; and The user interface and main processor of the hemodialysis machine control operation of both the hemodialysis machine and the dialysate generator, including control of operation of the blood pump, the dialysate pump, the at least one chemical reagent pump, and the at least one dialysate generator pump.

2. The hemodialysis system of claim 1, further comprising: The hemodialysis machine electrical terminals are fixed to the exterior of the hemodialysis machine housing, and the dialysate generator electrical terminals are fixed to the exterior of the dialysate generator housing, and the hemodialysis machine housing and dialysate generator housing are configured so that the hemodialysis machine housing can be engaged and mated to the dialysate generator housing by mating the hemodialysis machine electrical terminals to the dialysate generator electrical terminals.

3. The hemodialysis system of claim 1, wherein the hemodialysis machine further comprises a second reservoir for storing dialysate, the second reservoir being located within the dialysate generator housing and having a volume of between 0.5 liters and 5.0 liters, and the second reservoir being in the dialysate flow path to supply dialysate to the dialyzer.

Images