Automated peritoneal dialysis system with drainage and removal

Abstract

The peritoneal dialysis system (10) includes: a circulation machine (20) including a pump actuator (60); a disposable kit including a pumping section (126) operable with the pump actuator (60), a patient line (122e) positioned in fluid communication with the pumping section (126), and an outlet container (124a) positioned in fluid communication with the pumping section (126); and a control unit (50) configured to actuate the pumping section (126) with the pump actuator (60) to (i) perform peritoneal dialysis treatment in which fresh dialysis fluid is pumped to a patient through the patient line (122e) and used dialysis fluid is pumped from the patient to the outlet container (124a), and (ii) at the end of treatment, used dialysis fluid is pumped from the outlet container (124a) to the house drain through the patient line (122e).

Description

[0001] Priority requirements

[0002] This application claims priority and benefit from U.S. Provisional Application No. 63 / 185,050, filed May 6, 2021, entitled “Automated Peritoneal Dialysis Component,” the entire contents of which are incorporated herein by reference and are based upon. Technical Field

[0003] This disclosure generally relates to medical fluid therapy, and more particularly to dialysis fluid therapy. Background Technology

[0004] A person's kidneys can fail for a variety of reasons. Kidney failure causes a number of physiological disorders. The body is no longer able to balance water and minerals or eliminate the daily metabolic load. Toxic metabolic end products, such as urea, creatinine, uric acid, and others, can accumulate in the patient's blood and tissues.

[0005] Dialysis is used to treat declining kidney function, especially kidney failure. Dialysis removes waste products, toxins, and excess water from the body that would otherwise be removed by normally functioning kidneys. Dialysis, used to replace kidney function, is crucial for many people because it is a life-saving treatment.

[0006] One type of treatment for kidney failure is hemodialysis (“HD”), which typically uses diffusion to remove waste products from a patient’s blood. A diffusion gradient occurs across a semi-permeable dialyzer between the blood and an electrolyte solution called dialysate or dialysate fluid, causing diffusion.

[0007] Hemofiltration (“HF”) is an alternative renal replacement therapy that relies on the convective transport of toxins from a patient’s blood. HF is achieved by adding a replacement or alternative fluid to an extracorporeal circuit during treatment. During HF treatment, the replacement fluid and any fluid that accumulates in the patient between treatments are ultrafiltered, providing a convective transport mechanism that is particularly beneficial for removing medium and large molecules.

[0008] Hemodiafiltration (“HDF”) is a treatment that combines convective and diffusion clearance. HDF uses dialysate (similar to standard hemodialysis) flowing through the dialyzer to provide diffusion clearance. Additionally, a replacement solution is supplied directly to the extracorporeal circuit to provide convective clearance.

[0009] Most HD, HF, and HDF treatments are performed at a center. There is a growing trend towards home hemodialysis (“HHD”), partly because HHD can be performed daily, offering therapeutic benefits compared to center-based hemodialysis treatments typically performed every two or three weeks. Studies have shown that more frequent treatments remove more toxins and waste products and reduce fluid overload between dialysis sessions compared to patients receiving less frequent but potentially longer treatments. Patients receiving more frequent treatments do not experience as many drop cycles (fluid and toxin fluctuations) as patients at a center who have accumulated two or three days' worth of toxins before treatment. In some areas, the nearest dialysis center may be many miles from a patient's home, resulting in home visits taking up a large portion of the day. Treatment at a center near the patient's home may also take up a large portion of the patient's day. HHD can be performed while the patient is relaxing, working, or otherwise producing, either at night or during the day.

[0010] Another type of treatment for kidney failure is peritoneal dialysis (“PD”), which involves injecting a dialysis solution (also called dialysis fluid) into the patient’s peritoneal chambers via a catheter. The dialysis fluid comes into contact with the peritoneum within the patient’s peritoneal chambers. Waste, toxins, and excess water from the patient’s bloodstream through capillaries in the peritoneum and enter the dialysis fluid due to diffusion and osmosis, creating an osmotic gradient across the peritoneum. The osmotic agent in the PD fluid provides this osmotic gradient. Used or wasted dialysis fluid is drained from the patient, thus removing waste, toxins, and excess water from the body. This cycle is repeated, for example, multiple times.

[0011] Several types of peritoneal dialysis therapy exist, including continuous ambulatory peritoneal dialysis (“CAPD”), automated peritoneal dialysis (“APD”), tidal flow dialysis, and continuous flow peritoneal dialysis (“CFPD”). CAPD is a manual dialysis treatment. Here, the patient manually connects the implanted catheter to the drain line to allow used or discarded dialysis fluid to drain from the peritoneal chamber. The patient then switches the fluid connection so that the patient's catheter is connected to a fresh dialysis fluid bag to allow fresh dialysis fluid to be injected through the catheter into the patient's body. The patient disconnects the catheter from the fresh dialysis fluid bag and allows the dialysis fluid to reside in the peritoneal chamber, where waste, toxins, and excess water are transferred. After the residence period, the patient repeats the manual dialysis procedure, for example, four times a day. Manual peritoneal dialysis requires a significant investment of time and effort from the patient, leaving considerable room for improvement.

[0012] Automated peritoneal dialysis (“APD”) is similar to CAPD in that dialysis treatment includes draining, filling, and retention cycles. However, APD machines typically perform these cycles automatically while the patient is asleep. APD machines eliminate the need for patients to manually perform treatment cycles or deliver supplies throughout the day. An APD machine is fluidly connected to an implanted catheter, a source or bag of fresh dialysis fluid, and a drain tubing. The APD machine pumps fresh dialysis fluid from the source through the catheter and into the patient's peritoneal chamber. The APD machine also allows the dialysis fluid to remain within the peritoneal chamber and allows for the removal of waste, toxins, and excess water. The source may include multiple liters of dialysis fluid, comprising multiple solution bags.

[0013] The APD machine pumps used or discarded dialysis fluid from the patient's peritoneal cavity through a catheter to the drain line. Similar to the manual procedure, several drain, fill, and residence cycles occur within the dialysis device. A "final fill" may occur at the end of an APD treatment. The final fill fluid may remain in the patient's peritoneal chamber until the next treatment begins, or it may be manually emptied at some point during the day.

[0014] Known APD systems include machines or circulation systems that receive and actuate a pump cartridge with rigid and flexible components, the flexible components being deformable to perform pumping and valve operation. Sealing a fluid-operated disposable cartridge with a pneumatic path via a gasket to provide actuation has proven to be a potential field problem, potentially delaying treatment start time and impacting user experience. Pneumatic cartridge systems also generate noise, which can be a cause of customer dissatisfaction.

[0015] For each of the reasons mentioned above, an improved APD machine is needed. Summary of the Invention

[0016] This disclosure proposes an efficient automated peritoneal dialysis (“APD”) system and associated circulation machine that uses a disposable kit of peristaltic pump and tissue tubing and performs many of the functions discussed below. In one embodiment, the circulation machine of the system includes a peristaltic pump actuator capable of pumping in both directions. Flow in either direction travels through a disposable cartridge, which is part of the overall disposable kit.

[0017] The disposable cartridge is installed within the housing of the circulation machine, and in one embodiment, the cartridge is vertically mounted against an actuating surface of the housing and then enclosed between the actuating surface and a hinged door of the housing. A user interface for communicating with the control unit is located next to the door of the housing, allowing the patient or user to typically interact with a surface of the machine for inputting commands, receiving data, and loading the disposable cartridge.

[0018] In one embodiment, the system also includes a bag holder cover for multiple uses. The bag holder cover is sized so that the circulation machine can be stored inside the cover when not in use. The bag holder cover is also sized so that it can be positioned on top of the circulation machine when in use. The bag holder holds multiple containers or bags, such as multiple supply containers and one or more discharge containers. In one example, during treatment, multiple supply containers are located inside the bag holder cover, while the discharge container and the last-fill container are located on the outside and top of the cover. The bag holder cover may include color-coded markings at locations for loading containers or bags having tubing extending into the circulation machine through openings, wherein the openings have similar color-coded markings. Matching color-coded markings make it easy for patients or caregivers to identify which bag and tubing belongs to which location on the bag holder cover.

[0019] It is conceivable that the supply container or bag could later be used as an exit container or bag to reduce overall one-time costs. For example, suppose that the patient's body is full of exudate at the start of treatment. This exudate is first drained from the patient and delivered to an empty exit container. A first patient filler is then delivered to the patient from a first supply container, and after a specified residence period, it is delivered to either the same exit container or a different exit container, depending on the size of one or more exit containers. One or more exit containers are used to receive exudate until the first supply container is empty, after which the first supply container receives exudate after a residence period using PD fluid supplied from a second supply container. The first supply container may undergo multiple patient fills, residences, and drains until the second supply container is empty. At this point, the patient may receive a final filler of a different formulation of peritoneal dialysis fluid, which is retained in the patient until the next evening's treatment, or possibly until a change at noon.

[0020] At the end of treatment, multiple containers or bags are filled with effluent. To prevent the patient or caregiver from having to transport the discharge bags to a building drain, such as a toilet, sink, or bathtub, the circulation machine's control unit is programmed to prompt the user to remove the patient tubing from the patient transfer device and to transport the distal end of the patient tubing to the building drain. It should be understood that "building drain" as used herein refers to any type of drain provided in any type of building or dwelling, such as a residence, apartment, office building, hospital, clinic, public or private facility, etc. If necessary, a reusable extension line can be connected to the distal end of the patient tubing to reach the building drain. The patient or caregiver then presses the discharge button on the user interface, at which point the circulation machine actuates the peristaltic pump actuator in one direction to draw used dialysis fluid or effluent from each discharge container (one or more of which may be previous discharge containers) and pumps the used dialysis fluid through the patient tubing (and extension lines, if needed) to the building drain. The circulation system detects when each discharge container is empty (e.g., via a weighing scale and / or pressure sensor, discussed in detail below) and automatically switches valve actuators (e.g., pinch valve actuators) to sequence the discharge containers until each discharge container is empty. For any residual fresh dialysis fluid in the main supply container or the last-fill container, the above sequence is repeated. It should be understood that multiple discharge containers (one or more of which may be previous supply containers) can be discharged simultaneously or at the same time, for example, to save time. In this way, once the patient is disconnected from the patient line and presses the discharge button, the patient is free to begin their day.

[0021] As mentioned above, in one embodiment, the circulation machine uses a peristaltic pump. A peristaltic pump actuator, controlled by a control unit, is located on the actuation surface of the circulation machine. A disposable cartridge includes a peristaltic pump tube, which the user guides above the peristaltic pump actuator when the cartridge is loaded. During operation, the peristaltic pump actuator compresses the peristaltic pump tube against a raceway at multiple points. The operational proximity of the raceway to the peristaltic pump actuator makes tube loading difficult. Therefore, this circulation machine includes a movable raceway that, when a patient or caregiver opens the circulation machine door to load a cartridge, translates via a linkage to a position that does not obstruct the peristaltic pump actuator. After the cartridge is loaded, closing the circulation machine door causes the movable raceway to translate via a linkage to an operable position directly adjacent to the peristaltic pump tube. In an alternative embodiment, a motor and lead screw assembly or a linear actuator (e.g., a linear stepper motor) is provided to automatically translate the raceway to a position that does not obstruct the peristaltic pump actuator when the patient or caregiver opens the door of the circulation machine to load the cassette, and to automatically translate the raceway to an operable position when the door is closed. In yet another alternative embodiment, a motor and lead screw assembly or a linear actuator (e.g., a linear stepper motor) is provided, but instead, the patient or caregiver presses one or more buttons on the user interface to translate the raceway open or to an operable position.

[0022] In one embodiment, a raceway is mounted to a block or component that is translatable toward and away from the peristaltic pump actuator over an actuation surface. In addition to the translational movement of the component (and raceway), the movable raceway is also rotatable about a pivot located at one end of the raceway, the pivot being mounted to the translational component. The other end of the raceway is spring-loaded via a spring (e.g., a compression spring) defined between the end of the raceway and the component. As the component has translated toward the peristaltic pump actuator, the spring pushes the raceway about the pivot into a desired operating position around the peristaltic pump tubing. The pivoting raceway absorbs or allows variations due to tubing tolerances and can also provide a suppressive effect that helps reduce noise.

[0023] As mentioned above, in one embodiment, the circulation machine uses a pinch valve actuator, wherein the disposable cartridge is provided with a valve seat that receives the pinch valve actuator to block or close the fluid path provided by the disposable cartridge. Here, the cartridge is sealed to and covered by a flexible sheet (e.g., flexible plastic), and the pinch valve actuator presses the flexible sheet into the corresponding valve seat to close the corresponding fluid path. The pinch valve actuator retracts to open its corresponding fluid path.

[0024] Each pinch valve is driven by a linear actuator, which can be any suitable type of linear actuator, such as a linear stepper motor, providing the necessary amount of stroke (e.g., up to 10 mm) and the required amount of pressure applied to the cartridge sheet (e.g., 30 to 60 Newtons (“N”) or less). The linear actuator drives the valve plunger back and forth to press the cartridge sheet against the cartridge seat and allow the sheet to be removed from the cartridge seat. In one embodiment, the valve plunger includes a proximal actuator coupled to the linear actuator and a distal actuator slidably coupled to the proximal actuator. A spring (such as a wave spring or compression spring) may be provided with the plunger and positioned to bias the distal actuator outward relative to the proximal actuator. The variable distance provided by the spring allows the pinch valve to initially contact the cartridge sheet with a small closing force, which steadily increases as the spring is compressed. In one embodiment, a flexible diaphragm (such as a silicone diaphragm) is fixed to the actuating surface to cover the end of the distal actuator, such that the flexible diaphragm contacts the cartridge sheet. When the spring is fully compressed, the cassette sheet bears the full force of the linear actuator and the spring. Therefore, the spring provides a force damper, helping to protect the flexible membrane during multiple treatments and the cassette sheet during a single treatment. The spring also helps accommodate variations due to tolerances and loading of disposable cassettes, and may allow for smaller or less expensive linear actuators.

[0025] As mentioned, the disposable cartridge provides multiple valve seats, which may include a patient line valve seat, a first supply line valve seat, a second supply line valve seat, a final fill line valve seat, and a discharge line valve seat. In one embodiment, the patient line valve seat is fluidly separated from the first peristaltic tube port via an embedded fluid heating path (e.g., a serpentine path). When the disposable cartridge is installed for operation, the embedded fluid heating path is adjacent to a heater, such as a resistance plate heater.

[0026] In one embodiment, the first and second supply line valve seats, the last fill line valve seat, and the discharge line valve seat are each located in a common pit in fluid communication with the second peristaltic tube port. In this way, fresh dialysis fluid can be pumped in a first direction from any of the supply containers for the first and second supply line valve seats or the last fill line valve seat through the common pit and an embedded fluid heating path, where the fresh dialysis fluid can be heated, and then pumped from the patient line valve seat to the patient. Used dialysis fluid or effluent can be pumped in a second direction from the patient through the patient line valve seat and the embedded fluid heating path (where the used dialysis fluid is not heated), into the common pit, and exit the discharge line valve seat to the discharge container.

[0027] Any of the valve seats described herein may include a conical sealing surface surrounded by a plurality of shifting ribs, each shifting rib extending from a rigid wall of a disposable cartridge, wherein at least some of the shifting ribs are spaced apart to prevent or mitigate undesirable clogging of the conical sealing surface by a flexible sheet and to allow fresh or used dialysis fluid to flow through it. The shifting ribs may be completely separated from each other or extend from a common cylindrical base. The shifting ribs may be separated from the conical sealing surface or extend from the outer edge of the conical sealing surface. The shifting ribs prevent the flexible sheet from intruding into the conical sealing surface. The shifting ribs may also guide the corresponding pinch valve plunger toward the center of the valve seat while also providing a certain amount of clearance or play between the pinch valve plunger and the valve seat. In one embodiment, the conical sealing surface tapers to form a funnel shape leading to an opening that allows fresh or used dialysis fluid to flow into or out of the valve seat. In one embodiment, the opening extends through a port located on the opposite side of the rigid body of the disposable cassette, wherein the port sealably receives (attaches to) a tube or line, such as a patient line, supply line, or drain line. The tapered sealing surface may also include or define one or more circular sealing rings that are pressed into the flexible sheet when the flexible sheet is closed by the clamp valve.

[0028] In one embodiment, a first or patient pressure sensing chamber is located within a disposable cartridge and directly adjacent to the patient line valve seat. When the disposable cartridge is loaded, the patient pressure sensing chamber is adjacent to a first or patient pressure sensor, the output of which is sent to the circulation machine control unit. The output of the patient pressure sensor can be used to control the positive and negative pumping pressures experienced by the patient within safe pressure limits. A second or pumping pressure sensing chamber is located within the disposable cartridge and between the common pit and the second peristaltic tube port. When the disposable cartridge is loaded, the pumping pressure sensing chamber is adjacent to a second or pumping pressure sensor, the output of which is sent to the circulation machine control unit. The output of the pumping pressure sensor can be used to detect blockages and / or empty supply lines.

[0029] The disposable cartridge may also include one or more areas adjacent to a thermocouple or other temperature sensor that outputs to the control unit when loaded for operation. The temperature sensing area may, for example, be placed at the end of the embedded fluid heating path directly adjacent to the patient pressure sensing chamber, allowing monitoring of the outlet temperature of fresh dialysis fluid to the patient and control of that outlet temperature to a desired temperature, such as body temperature or 37°C, and performed, for example, via a proportional-integral-derivative (“PID”) routine executed by the control unit using feedback from the temperature sensor. If desired, a second temperature sensor may be positioned to detect the temperature at the inlet of the embedded fluid heating path, which, if needed, can also provide useful information for the PID routine.

[0030] It is conceivable that a pressure sensor is mounted in the actuating surface of the circulation machine, such that when a disposable cassette is loaded for operation, the cassette sheet (which may be polyvinyl chloride (“PVC”)) is contacted by the pressure sensor and placed under tension to generate a baseline force measured by the pressure sensor. The pressure of fresh or used dialysis fluid causes further displacement (or attempts to displace) of the cassette sheet, thereby increasing or decreasing the fluid force acting on the pressure sensor relative to the baseline force. A control unit correlates the force difference caused by positive or negative fluid pressure with the actual fluid pressure value, which is used for pressure control, and can be displayed by a user interface and / or stored for transmission to a remote computer for evaluation.

[0031] The pre-tensioning of the pressure sensor onto the sheet material results in a pressure sensing mechanism with high sensitivity and resolution, but it may be susceptible to temperature sensitivity. Therefore, temperature compensation can be envisioned. Here, a component is added to modify the voltage (or current) output from the pressure sensor, which is a function of the measured temperature (e.g., using a thermocouple discussed above) multiplied by an empirically determined temperature scaling factor, to form a compensated voltage output, which is then converted into a compensated positive or negative pressure or related to a compensated positive or negative pressure.

[0032] As mentioned above, the pre-tensioning of the cassette sheet by a pressure sensor results in a pressure sensing mechanism with high sensitivity and resolution, but it can also be susceptible to mechanical creep sensitivity. To combat creep sensitivity, in one embodiment, the control unit is programmed to pre-treat the cassette sheet before treatment (e.g., during a setting period) to eliminate most of the pressure signal variation due to creep before pressure measurements take effect. To this end, after the disposable cassette is infused, the control unit closes all clamp valves and then actuates a peristaltic pump actuator to pressurize the interior of the cassette (including the pressure chamber) to stretch the cassette sheet. The control unit can be programmed to cause the pump actuator to periodically oscillate the cassette fluid pressure multiple times over a specified duration, where the upper limit pressure can be, for example, 100% to 150% of the maximum operating pressure set for treatment. Pre-treating the cassette sheet helps to make the uncompensated pressure readings more accurate, while temperature compensation helps to make the final pressure readings more accurate.

[0033] In one embodiment, the system and circulation machine of this disclosure employ a weighing scale with multiple force sensors to monitor the amount of fresh dialysis fluid delivered to the patient, the amount of used dialysis fluid removed from the patient, and thereby enabling the control unit to calculate the amount of ultrafiltration (“UF”) removed from the patient. The weighing scale and force sensors are advantageous for several reasons. First, the weighing scale is relatively accurate compared to other volumetric measurement techniques. Second, the weighing scale reduces pump costs because the pump actuator can be a relatively simple peristaltic pump actuator, and the disposable portion of the pump can be a simple peristaltic pump tubing.

[0034] One drawback of using force sensors is calibration. Over time, force sensor readings may become inaccurate, thus requiring recalibration. This circulation machine and associated system provide a weighing scale with multiple force sensors and an onboard structure, as well as a method for calibrating the weighing scale. In one embodiment, the weighing scale includes a weighing plate located at the top of the circulation machine, supporting the weight of the bag holder hood, each solution and discharge container, and associated fresh and used dialysis fluid. The weighing plate and each weighed item on the weighing plate are supported by multiple (e.g., four) force sensors that collectively measure the total mass (bag holder hood, container, and fluid) placed on the weighing plate. In one embodiment, the onboard calibration structure includes a fifth force sensor and a linear actuator (which may be of the same type used for pinch valves) located between the fifth force sensor and the weighing plate.

[0035] The linear actuator includes an actuation output shaft fixed to the weighing plate, allowing the linear actuator to apply a tensile or downward force to the weighing plate. In one embodiment, the tensile force is applied to the center of mass on the underside of the weighing plate. An additional calibration force sensor measures the total applied force, while four operational force sensors each measure a portion or a quarter of the total force. If the operational force sensors each perform correctly, the sum of their outputs should equal the total force measured by the calibration force sensor. In one example, assume the linear actuator applies a tensile force of 1000 Newtons (“N”). Subsequently, the calibration force sensor should output 1000 N, while the equidistant operational force sensors 102a to 102d should each read 250 N, totaling 1000 N.

[0036] Because the calibration force sensor is not frequently used, a calibration algorithm is applied assuming that the output of the calibration force sensor is more accurate than the collective output of the operational force sensor used in each treatment. Therefore, if a mismatch exists between the calibration force sensor reading and the collective output of the operational force sensor during calibration, the control unit using the calibration algorithm scales or offsets the collective output of the operational force sensor to match the calibration force sensor reading. In the example above, assume the operational force sensor actually reads a total of 995N instead of 1000N. The operational force sensor reading is correspondingly 0.5% lower. The control unit is thus configured to modify the collective output of the operational force sensor during treatment with a calibration factor of 1000 / 995 or 1.005.

[0037] Because the calibration force sensor is not used frequently, the calibration algorithm assumes that the output of the calibration force sensor is more accurate than the collective output of the operational force sensor used in each treatment. Therefore, if a mismatch exists between the calibration force sensor reading and the collective output of the operational force sensor during calibration, the control unit using the calibration algorithm scales or offsets the collective output of the operational force sensor to match the calibration force sensor reading. In the example above, it is assumed that the operational force sensor actually reads a total of 605 Newtons instead of 600 Newtons. Therefore, the operational force sensor only senses 395 Newtons of the applied 400 Newtons. The operational force sensor reading is correspondingly 1.3% lower. The control unit of the circulator is thus configured to modify the collective output of the operational sensor during treatment with a calibration factor of 400 / 395 or 1.01.

[0038] Force sensor calibration routines or algorithms are executed on a certain expectation basis, for example, before each treatment begins. It should also be understood that because many weight values ​​monitored and collected during treatment are weight differences, the error in the collective output of the force sensors tends to self-cancel, assuming the error does not change during treatment. For example, the mass associated with a two-liter patient filling volume is monitored and controlled by the collective output of the force sensors, thus recording the mass decrease during patient filling. The volume and mass associated with patient expulsion can be preset in the control unit, for example, by a coefficient such as 1.3 multiplied by the filling volume to account for the patient's UF being moved into the expulsion volume. The volume and mass associated with patient expulsion can alternatively be open-ended and controlled by sensing a characteristic rise in negative pressure through a pump pressure sensing chamber and associated pressure sensors, indicating that the patient has been substantially expelled and further expulsion may cause the patient discomfort. In either case, the force sensors sense an increase in weight during patient expulsion, which should tend to eliminate any error in the force sensors.

[0039] Based on the disclosure set forth herein, and without limiting this disclosure in any way, in a first aspect which may be combined with any other aspect or part thereof, a peritoneal dialysis system includes: a circulation machine including a pump actuator; a disposable kit including a pumping section operable with the pump actuator, a patient line positioned in fluid communication with the pumping section, and an outlet container positioned in fluid communication with the pumping section; and a control unit configured to cause the pump actuator to actuate the pumping section (i) for peritoneal dialysis treatment, wherein fresh dialysis fluid is pumped to the patient through the patient line and used dialysis fluid is pumped from the patient to the outlet container, and (ii) at the end of treatment, the used dialysis fluid is pumped from the outlet container through the patient line to a house drain.

[0040] In a second aspect of this disclosure, which may be combined with any other aspect or part thereof, the pump actuator is a peristaltic pump actuator, and the pumping portion of the disposable kit includes peristaltic pump tubing.

[0041] In a third aspect of this disclosure, which may be combined with any other aspect or part thereof, the peritoneal dialysis system includes an extension line configured to connect to the patient line to reach the house drain when needed.

[0042] In the fourth aspect of this disclosure, which can be combined with any other aspect or part thereof, the extension pipeline is reusable.

[0043] In a fifth aspect of this disclosure, which may be combined with any other aspect or part thereof, the peritoneal dialysis system includes a user interface that communicates with a control unit, and wherein the user interface is configured to prompt the patient to disconnect the patient line and move the patient line toward the house drain at the end of treatment.

[0044] In a sixth aspect of this disclosure, which may be combined with any other aspect or part thereof, the peritoneal dialysis system includes a user interface that communicates with a control unit, and wherein the user interface is configured to provide or enable a drain button at the end of treatment for initiating the pumping of used dialysis fluid from the drain container through the patient line to the house drain.

[0045] In a seventh aspect of this disclosure, which may be combined with any other aspect or part thereof, the user interface is also configured to require confirmation that the drain line is in fluid communication with the house drain before providing or enabling the drain button.

[0046] In an eighth aspect of this disclosure, which may be combined with any other aspect or part thereof, the circulation machine includes a patient valve actuator operating with a patient valve seat provided by a disposable kit, and a discharge valve actuator operating with a discharge valve seat provided by a disposable kit, wherein a control unit is configured to allow the patient valve actuator and the discharge valve actuator to flow through the patient valve seat and the discharge valve seat to pump used dialysis fluid from the discharge container through the patient line to the house drain.

[0047] In the ninth aspect of this disclosure, which may be combined with any other aspect or part thereof, at least one of the patient valve actuator or the discharge valve actuator is a pinch valve actuator.

[0048] In a tenth aspect of this disclosure, which may be combined with any other aspect or part thereof, the peritoneal dialysis system includes a supply container positioned in fluid communication with the pumping portion of a disposable kit, wherein the supply container is used to pump fresh dialysis fluid through the patient line to the patient during peritoneal dialysis treatment.

[0049] In the eleventh aspect of this disclosure, which may be combined with any other aspect or part thereof, the supply container is later used during peritoneal dialysis treatment to receive used dialysis fluid from the patient.

[0050] In a twelfth aspect of this disclosure, which may be combined with any other aspect or part thereof, the circulation machine includes a sensor operatively in communication with a control unit, and wherein the control unit is configured to use the output from the sensor to determine when one of the discharge container or a supply container subsequently used as a discharge container is empty or substantially empty after its used dialysate has been pumped to the house drain, and thereafter switch to another of the discharge container or a supply container subsequently used as a discharge container to pump its used dialysate to the house drain.

[0051] In the thirteenth aspect of this disclosure, which may be combined with any other aspect or part thereof, the sensor is a weight sensor or a pressure sensor.

[0052] In the fourteenth aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is also configured to cause the pump actuator to actuate the pumping section at the end of treatment to pump the remaining fresh dialysis fluid from the supply container through the patient line to the house drain.

[0053] In a fifteenth aspect of this disclosure, which may be combined with any other aspect or part thereof, the discharge container is a first discharge container and includes a second discharge container positioned in fluid communication with the pumping portion of the disposable kit, wherein the circulation machine includes sensors operatively in communication with a control unit, and wherein the control unit is configured to use output from the sensors to determine when the first discharge container is empty or substantially empty after pumping its used dialysate to the house drain, and thereafter switch to the second discharge container to pump its used dialysate to the house drain.

[0054] In the sixteenth aspect of this disclosure, which can be combined with any other aspect or part thereof, the sensor of the fifteenth aspect is a weight sensor or a pressure sensor.

[0055] In the seventeenth aspect of this disclosure, which may be combined with any other aspect or part thereof, the discharge container is a first discharge container and includes a second discharge container positioned in fluid communication with the pumping portion of the disposable kit, and wherein a control unit is configured to discharge the first discharge container and the second discharge container simultaneously.

[0056] In an eighteenth aspect of this disclosure, which may be combined with any other aspect or part thereof, the peritoneal dialysis system includes a circulation machine comprising: a pump actuator; a disposable kit including a pumping section operable with the pump actuator, a patient line positioned in fluid communication with the pumping section, and an outlet line positioned in fluid communication with the pumping section; and a control unit configured to cause the pump actuator to actuate the pumping section (i) for peritoneal dialysis treatment, wherein fresh dialysis fluid is pumped to the patient through the patient line and used dialysis fluid is pumped out of the patient through the outlet line, and (ii) at the end of treatment, the used dialysis fluid is pumped to the house drain through the outlet line and the patient line.

[0057] In the nineteenth aspect of this disclosure, which may be combined with any other aspect or part thereof, the discharge line is in fluid communication with a discharge container, and wherein the discharge container is initially provided as a discharge container or a supply container filled with fresh dialysis fluid.

[0058] In the twentieth aspect of this disclosure, which may be combined with any other aspect or part thereof, the patient line and the drain line are separated by a disposable cartridge of a disposable kit, and wherein, at the end of treatment, the used dialysis fluid is pumped through the drain line, through the disposable cartridge, and through the patient line to the house drain.

[0059] In a twenty-first aspect of this disclosure, which may be combined with any other aspect or part thereof, the disposable cartridge includes a pressure sensing chamber positioned to enable the detection of pressure changes indicating that the discharge container in fluid communication with the discharge line is empty, and wherein a control unit thereafter causes a switching to discharge used dialysis fluid from a different source to the house drain at the end of treatment.

[0060] In a twenty-second aspect of this disclosure, which may be combined with any other aspect or part thereof, the circulation machine includes a weighing scale, wherein a discharge container in fluid communication with a discharge line is positioned to be weighed by the weighing scale, and wherein a control unit uses an output from the weighing scale indicating that the discharge container is empty to induce a switching to discharge used dialysis fluid from a different source to the house drain at the end of treatment.

[0061] In a twenty-third aspect of this disclosure, which may be combined with any other aspect or part thereof, the peritoneal dialysis system includes: a circulation machine including a pump actuator; a disposable kit including a pumping section operable with the pump actuator, a patient line positioned in fluid communication with the pumping section, and an outlet container positioned in fluid communication with the pumping section; and a control unit configured to cause the pump actuator to actuate the pumping section (i) for peritoneal dialysis treatment, wherein fresh dialysis fluid is pumped to the patient through the patient line and used dialysis fluid is pumped from the patient to the outlet container, and (ii) at the end of treatment, used dialysis fluid is pumped from the outlet container through the patient line to a desired destination.

[0062] In the twenty-fourth aspect of this disclosure, which may be combined with any other aspect or part thereof, the desired destination includes a house drain pipe or another container positioned in fluid communication with the pumping section.

[0063] In the twenty-fifth aspect of this disclosure, which may be combined with any other aspect or part thereof, pumping used dialysis fluid from the discharge container through the patient line during (ii) comprises: actuating a pumping portion in a first direction to at least partially fill the patient line with the used dialysis fluid, and then actuating the pumping portion in a second direction to move the used dialysis fluid from the patient line to a desired destination.

[0064] In a twenty-sixth aspect of this disclosure, which may be combined with any other aspect or part thereof, the disposable medical fluid cartridge includes: a pumping portion; a patient line seat positioned in fluid communication with the pumping portion; a rigid body defining a common pit in fluid communication with the pumping portion; at least one supply line seat located in the common pit; and a discharge line seat located in the common pit.

[0065] In the twenty-seventh aspect of this disclosure, which can be combined with any other aspect or part thereof, the patient line valve seat is provided by a rigid body.

[0066] In the twenty-eighth aspect of this disclosure, which may be combined with any other aspect or part thereof, the pumping portion includes a peristaltic pump tube attached to a rigid body.

[0067] In the twenty-ninth aspect of this disclosure, which may be combined with any other aspect or part thereof, the pumping portion includes a pump chamber defined by a rigid body.

[0068] In the thirtieth aspect of this disclosure, which may be combined with any other aspect or part thereof, the rigid body defines an embedded fluid heating path located between the patient line valve seat and the pumping portion.

[0069] In a thirty-first aspect of this disclosure, which may be combined with any other aspect or part thereof, the disposable medical fluid cartridge includes a temperature sensing region located between a patient line seat and an embedded fluid heating path.

[0070] In the thirty-second aspect of this disclosure, which may be combined with any other aspect or part thereof, the embedded fluid heating path is configured such that fresh dialysis fluid flows upward during perfusion to remove air through the patient line valve seat.

[0071] In the thirty-third aspect of this disclosure, which may be combined with any other aspect or part thereof, the disposable medical fluid cartridge includes at least one of the following sensing chambers: a pump pressure sensing chamber located between a discharge line valve seat and a first end of an embedded fluid heating path, or a patient pressure sensing chamber located between a patient line valve seat and a second end of an embedded fluid heating path.

[0072] In the thirty-fourth aspect of this disclosure, which may be combined with any other aspect or part thereof, the disposable medical fluid cartridge includes at least one of the following lines: a patient line in fluid communication with a patient line valve seat, at least one supply line in fluid communication with at least one supply line valve seat, or a discharge line in fluid communication with a discharge line valve seat.

[0073] In the thirty-fifth aspect of this disclosure, which may be combined with any other aspect or part thereof, the disposable medical fluid cartridge includes at least one of the following sensing chambers: a pump pressure sensing chamber located near the patient line valve seat, or a pump pressure sensing chamber located near a common pit.

[0074] In the thirty-sixth aspect of this disclosure, which may be combined with any other aspect or part thereof, the disposable medical fluid cartridge includes a flexible sheet sealed to a rigid body, the flexible sheet being bent to open and close the at least one supply line valve seat and the discharge line valve seat.

[0075] In the thirty-seventh aspect of this disclosure, which may be combined with any other aspect or part thereof, the rigid body includes a rigid wall defining a common pit, to which a flexible sheet is sealed to enclose the common pit.

[0076] In the thirty-eighth aspect of this disclosure, which may be combined with any other aspect or part thereof, at least one of the patient line seat, the at least one supply line seat, or the discharge line seat includes a conical sealing surface surrounded by a plurality of displacement ribs, at least some of which are spaced apart to mitigate intrusion of the flexible sheet into the conical sealing surface.

[0077] In the thirty-ninth aspect of this disclosure, which may be combined with any other aspect or part thereof, the common pit includes a ramp configured to guide air in the common pit toward a discharge line seat.

[0078] In the fortieth aspect of this disclosure, which may be combined with any other aspect or part thereof, the discharge line valve seat is positioned relative to at least one supply line valve seat in the common pit such that the discharge line valve seat is higher in height than the at least one supply line valve seat to direct air toward the discharge line valve seat when a disposable medical fluid cartridge is loaded for operation.

[0079] In a forty-first aspect of this disclosure, which may be combined with any other aspect or part thereof, the peritoneal dialysis system includes: a circulation machine including a pump actuator, a patient line valve actuator, at least one supply line valve actuator, and an exhaust line valve actuator; and a disposable medical fluid cartridge including a pumping section configured to operate with the pump actuator, a patient line valve seat configured to operate with the patient line valve actuator, a rigid body defining a common pit, at least one supply line valve seat located in the common pit and configured to operate with at least one supply line valve actuator, and an exhaust line valve seat located in the common pit and configured to operate with the exhaust line valve actuator.

[0080] In the forty-second aspect of this disclosure, which may be combined with any other aspect or part thereof, the circulation machine is configured to perform patient discharge followed by patient filling, in which used dialysis fluid enters a common pit, and in which fresh dialysis fluid enters a common pit.

[0081] In the forty-third aspect of this disclosure, which may be combined with any other aspect or part thereof, during patient discharge, an exhaust line valve actuator is actuated such that used dialysis fluid can exit the common pit via the exhaust line valve seat, and wherein during patient filling, one of the at least one supply line valve actuator is actuated such that fresh dialysis fluid can enter the common pit via one of the at least one supply line valve seats.

[0082] In the forty-fourth aspect of this disclosure, which may be combined with any other aspect or part thereof, during patient discharge and patient filling, the patient line valve actuator is actuated so that used and fresh dialysis fluid can flow through the patient line valve seat, respectively.

[0083] In the forty-fifth aspect of this disclosure, which may be combined with any other aspect or part thereof, a valve seat for a disposable medical fluid cartridge includes: a rigid wall; a tapered sealing surface extending from the rigid wall around an opening formed in the rigid wall; and a plurality of displacement ribs extending from the rigid wall or from the outer edge of the tapered sealing surface to surround the tapered sealing surface, the displacement ribs being spaced apart to mitigate undesirable clogging of the tapered sealing surface.

[0084] In the forty-sixth aspect of this disclosure, which can be combined with any other aspect or part thereof, the displacement ribs are separate from each other or extend from a common cylindrical base.

[0085] In the forty-seventh aspect of this disclosure, which may be combined with any other aspect or part thereof, the conical sealing surface is cylindrical, and the displacement ribs together form a cylindrical shape surrounding the conical sealing surface.

[0086] In the forty-eighth aspect of this disclosure, which may be combined with any other aspect or part thereof, the conical sealing surface forms a funnel shape leading to the opening.

[0087] In the forty-ninth aspect of this disclosure, which may be combined with any other aspect or part thereof, the opening extends through a port located on the side of the rigid wall opposite to the tapered sealing surface and the displacement rib.

[0088] In the fiftieth aspect of this disclosure, which may be combined with any other aspect or part thereof, the conical sealing surface includes at least one circular sealing ring for pressing into a mating sealing member.

[0089] In a fifty-first aspect of this disclosure, which may be combined with any other aspect or part thereof, the pinch valve includes: a linear actuator; a proximal actuator coupled to the linear actuator; a distal actuator slidably engaged to the proximal actuator; and a spring positioned and arranged to bias the distal actuator outward relative to the proximal actuator.

[0090] In the fifty-second aspect of this disclosure, which may be combined with any other aspect or part thereof, the linear actuator includes a linear stepper motor.

[0091] In the fifty-third aspect of this disclosure, which may be combined with any other aspect or part thereof, the proximal actuator and the distal actuator form a valve plunger.

[0092] In the fifty-fourth aspect of this disclosure, which may be combined with any other aspect or part thereof, the proximal actuator includes a larger diameter portion and a smaller diameter portion, and wherein the distal actuator includes a cylindrical opening that slidably receives the smaller diameter portion of the proximal actuator.

[0093] In the fifty-fifth aspect of this disclosure, which may be combined with any other aspect or part thereof, the spring is positioned between a step transitioning between a larger diameter portion and a smaller diameter portion and a distal actuator.

[0094] In the fifty-sixth aspect of this disclosure, which can be combined with any other aspect or part thereof, the spring is constrained by the smaller diameter portion of the proximal actuator.

[0095] In the fifty-seventh aspect of this disclosure, which may be combined with any other aspect or part thereof, the outer diameter of the distal actuator is at least substantially equal to the outer diameter of the larger diameter portion of the proximal actuator.

[0096] In the fifty-eighth aspect of this disclosure, which may be combined with any other aspect or part thereof, the spring is a wave spring or a compression spring.

[0097] In the fifty-ninth aspect of this disclosure, which may be combined with any other aspect or part thereof, one of the proximal actuators or the distal actuator defines at least one recess, and the other of the proximal actuators or the distal actuator includes at least one spring arm that mechanically engages in said at least one recess.

[0098] In the sixtieth aspect of this disclosure, which may be combined with any other aspect or part thereof, the dimensions of the at least one groove are designed to provide a travel length of the distal actuator relative to the proximal actuator, the travel length being equal to or greater than the uncompressed length of the spring.

[0099] In a sixty-first aspect of this disclosure, which may be combined with any other aspect or part thereof, the dialysis machine includes: an actuating surface on which a fluid transport member is mounted for dialysis treatment; an orifice formed in the actuating surface; and a pinch valve including a linear actuator, a proximal actuator coupled to the linear actuator, a distal actuator slidably engaged with the proximal actuator, and a spring positioned and arranged to bias the distal actuator outward relative to the proximal actuator, wherein the pinch valve is mounted within the machine such that the distal actuator extends through the orifice to block a portion of the fluid transport member.

[0100] In the sixty-second aspect of this disclosure, which may be combined with any other aspect or part thereof, the orifice is covered by a flexible membrane, and wherein a distal actuator bends the flexible membrane to block a portion of the fluid-carrying member.

[0101] In the sixty-third aspect of this disclosure, which may be combined with any other aspect or part thereof, a pinch valve is installed within the machine such that the spring is compressed before that portion of the fluid-carrying component is subjected to a complete blocking force applied by a linear actuator.

[0102] In the sixty-fourth aspect of this disclosure, which may be combined with any other aspect or part thereof, the orifice is a first orifice, and the pinch valve is a first pinch valve, wherein the actuating surface defines a second orifice adjacent to the first orifice, and it includes a second pinch valve mounted within the machine such that the distal actuator of the second pinch valve extends through the second orifice to block a second portion of the fluid transport member.

[0103] In a sixty-fifth aspect of this disclosure, which may be combined with any other aspect or part thereof, the dialysis machine includes a control unit programmed to sequence a first clamp valve and a second clamp valve according to a pre-programmed order.

[0104] In a sixty-sixth aspect of this disclosure, which may be combined with any other aspect or part thereof, a dialysis machine operable with a disposable kit having a peristaltic pump tubing includes: an actuating surface for receiving the disposable kit; a peristaltic pump actuator extending from the actuating surface, operable with the peristaltic pump tubing; a member translatable along the actuating surface; a raceway pivotally connected to the member at a first end via a pivot; and a spring biased to push a second end of the raceway outwardly around the pivot and from the member.

[0105] In the sixty-seventh aspect of this disclosure, which may be combined with any other aspect or part thereof, the dialysis machine includes a stop positioned to limit the distance by which a spring can push a second end of the raceway outward from the member.

[0106] In the sixty-eighth aspect of this disclosure, which can be combined with any other aspect or part thereof, the spring is arranged around the stop.

[0107] In the sixty-ninth aspect of this disclosure, which may be combined with any other aspect or part thereof, the stop is connected to the member and travels with the member.

[0108] In the seventieth aspect of this disclosure, which may be combined with any other aspect or part thereof, the stop extends through an opening or aperture formed in the second end of the member and includes a head that is at least one size larger than the opening or aperture, and a spring is biased to push the second end of the member against the head.

[0109] In the seventy-first aspect of this disclosure, which may be combined with any other aspect or part thereof, the spring is a compression spring or a tension spring.

[0110] In the seventy-second aspect of this disclosure, which may be combined with any other aspect or part thereof, the member includes a base defining an arc whose radius substantially matches the radius of the raceway.

[0111] In the seventy-third aspect of this disclosure, which may be combined with any other aspect or part thereof, the dialysis machine includes a stop positioned to prevent spring-induced pivoting of the raceway when the radius of the raceway is at least substantially equal to the radius of the arc.

[0112] In the seventy-fourth aspect of this disclosure, which may be combined with any other aspect or part thereof, an actuating surface defines a linear track along which the member translates, and the lower surface of the member includes a track receiver sized to operate in conjunction with the linear track.

[0113] In the seventy-fifth aspect of this disclosure, which may be combined with any other aspect or part thereof, the linear track and track receiver are configured such that the linear track slidably holds the member against the actuating surface.

[0114] In the seventy-sixth aspect of this disclosure, which may be combined with any other aspect or part thereof, the member defines at least one groove for enabling the member to be slidably attached to an actuating surface.

[0115] In the seventy-seventh aspect of this disclosure, which may be combined with any other aspect or part thereof, the dialysis machine includes a door configured to open and close relative to an actuation surface, and further includes a linkage positioned and arranged to translate a raceway away from a peristaltic pump actuator when the door is open, and to translate the raceway to an operable position relative to the peristaltic pump actuator when the door is closed.

[0116] In a seventy-eighth aspect of this disclosure, which may be combined with any other aspect or part thereof, the dialysis machine includes a door configured to open and close relative to an actuating surface, and further includes a motor assembly configured to translate a raceway away from a peristaltic pump actuator and to translate the raceway to an operable position relative to the peristaltic pump actuator at different times.

[0117] In the seventy-ninth aspect of this disclosure, which can be combined with any other aspect or part thereof, the motor mechanism includes a motor operable with a lead screw or linear actuator.

[0118] In the eightieth aspect of this disclosure, which may be combined with any other aspect or part thereof, the motor mechanism is configured to (i) automatically translate the raceway away from the peristaltic pump actuator when the door is opened, and automatically translate the raceway to an operable position relative to the peristaltic pump actuator when the door is closed, or (ii) translate the raceway away from the peristaltic pump actuator and / or translate the raceway to an operable position relative to the peristaltic pump actuator at different times in response to at least one user interface input.

[0119] In an eighty-first aspect of this disclosure, which may be combined with any other aspect or part thereof, a dialysis machine operable with a disposable kit having a peristaltic pump tube includes: an actuation surface for receiving the disposable kit; a peristaltic pump actuator extending from the actuation surface, the peristaltic pump actuator operable with the peristaltic pump tube; a raceway translatable along the actuation surface; a door configured to open and close relative to the actuation surface; and a linkage or motor mechanism configured to (i) translate the raceway away from the peristaltic pump actuator for moving the peristaltic pump tube to a position abutting the peristaltic pump actuator, and (ii) translate the raceway to an operable position relative to the peristaltic pump tube.

[0120] In the eighty-second aspect of this disclosure, which may be combined with any other aspect or part thereof, a link is provided, wherein the link is constructed and arranged such that (i) is performed when the door is open and (ii) is performed when the door is closed.

[0121] In the eighty-third aspect of this disclosure, which may be combined with any other aspect or part thereof, a motor mechanism is provided, wherein the motor mechanism is constructed and arranged such that it automatically performs (i) when the door is opened and automatically performs (ii) when the door is closed.

[0122] In the eighty-fourth aspect of this disclosure, which may be combined with any other aspect or part thereof, a motor mechanism is provided, wherein at least one of (i) or (ii) is performed in response to user interface input.

[0123] In the eighty-fifth aspect of this disclosure, which may be combined with any other aspect or part thereof, the motor mechanism includes a motor operable in conjunction with a lead screw or linear actuator.

[0124] In an eighty-sixth aspect of this disclosure, which may be combined with any other aspect or part thereof, a medical fluid system includes: a medical fluid pump actuator; a medical fluid delivery kit including a flexible sheet; a temperature sensor positioned and arranged to sense the temperature of a medical fluid flowing through the medical fluid delivery kit; a pressure sensor positioned and arranged to contact the flexible sheet when the medical fluid delivery kit is loaded for operation with the medical fluid pump actuator; and a control unit configured to (i) pre-treat the flexible sheet for operation with the pressure sensor by causing the medical fluid pump actuator to apply pressure to the flexible sheet, and (ii) use the output from the temperature sensor in a compensation algorithm that modifies the output from the pressure sensor.

[0125] In the eighty-seventh aspect of this disclosure, which may be combined with any other aspect or part thereof, the medical fluid pump actuator is a peristaltic pump actuator.

[0126] In the 88th aspect of this disclosure, which may be combined with any other aspect or part thereof, the pressure sensor is positioned such that when the medical fluid transport kit is loaded to operate with a medical fluid pump actuator, the flexible sheet is placed under tension via contact with the pressure sensor.

[0127] In the eighty-ninth aspect of this disclosure, which may be combined with any other aspect or part thereof, the pressure sensor may operate together with the pressure chamber portion of the flexible sheet.

[0128] In the 90th aspect of this disclosure, which may be combined with any other aspect or part thereof, the pressure applied during (i) is fluid pressure.

[0129] In the ninety-first aspect of this disclosure, which may be combined with any other aspect or part thereof, the pressure applied during (i) is a cyclic up-and-down pressure.

[0130] In the ninety-second aspect of this disclosure, which may be combined with any other aspect or part thereof, the pressure applied during (i) is 100% to 150% of the maximum operating pressure supplied during treatment.

[0131] In the ninety-third aspect of this disclosure, which may be combined with any other aspect or part thereof, the medical fluid system includes a plurality of valves operable with a medical fluid delivery kit, and wherein a control unit causes the plurality of valves to close during (i).

[0132] In the ninety-fourth aspect of this disclosure, which can be combined with any other aspect or part thereof, the algorithm is V. T = V0 + gT, where V0 is the output from the pressure sensor, V T It is the modified pressure output, g is the temperature proportionality coefficient, and T is the sensed temperature.

[0133] In the ninety-fifth aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to (i) update the temperature compensation algorithm periodically whenever the output from the pressure sensor is read by the control unit or (ii) periodically.

[0134] In the ninety-sixth aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to use the modified output from the pressure sensor in (ii) for at least one of: (a) controlling the medical fluid pump actuator to pump within the patient pressure limit, (b) determining the condition of a blocked line, or (c) determining the condition of an empty container.

[0135] In a ninety-seventh aspect of this disclosure, which may be combined with any other aspect or part thereof, a medical fluid system includes: a medical fluid pump actuator; a medical fluid delivery kit including a flexible sheet; a pressure sensor positioned such that when the medical fluid delivery kit is loaded for operation with the medical fluid pump actuator, the flexible sheet is under tension via contact with the pressure sensor; and a control unit configured to pre-treat the flexible sheet for operation with the pressure sensor by causing the medical fluid pump actuator to apply pressure to the flexible sheet.

[0136] In the ninety-eighth aspect of this disclosure, which may be combined with any other aspect or part thereof, the pressure applied during pretreatment is fluid pressure.

[0137] In the ninety-ninth aspect of this disclosure, which may be combined with any other aspect or part thereof, the pressure applied during pretreatment is a cyclic up-and-down pressure.

[0138] In the hundredth aspect of this disclosure, which may be combined with any other aspect or part thereof, the pressure applied during pretreatment is 100% to 150% of the maximum operating pressure supplied during treatment.

[0139] In a first 101 aspect of this disclosure, which may be combined with any other aspect or part thereof, the medical fluid system includes a plurality of valves operable with a medical fluid delivery kit, and wherein a control unit causes the plurality of valves to close during pretreatment.

[0140] In a first 102nd aspect of this disclosure, which may be combined with any other aspect or part thereof, a medical fluid system includes: a medical fluid pump actuator; a medical fluid transport kit including a flexible sheet; a temperature sensor positioned and arranged to sense the temperature of a medical fluid flowing through the medical fluid transport kit; a pressure sensor positioned such that the flexible sheet is under tension via contact with the pressure sensor when the medical fluid transport kit is loaded for operation with the medical fluid pump actuator; and a control unit configured to use the output from the temperature sensor in a compensation algorithm that modifies the output from the pressure sensor.

[0141] In the 103rd aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to (i) update the temperature compensation algorithm periodically whenever the output from the pressure sensor is read by the control unit or (ii) periodically.

[0142] In the first 104th aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to use a modified output from a pressure sensor for at least one of: (i) controlling a medical fluid pump actuator to pump within the patient pressure limit, (ii) determining a line blockage, or (iii) determining a container is empty.

[0143] In a first 105th aspect of this disclosure, which may be combined with any other aspect or part thereof, a dialysis machine operable with a disposable kit having at least one container includes: a pump actuator operable to pump dialysis fluid into and / or from at least one container; a weighing plate positioned to support at least one container; a plurality of operational force sensors positioned to support the weighing plate; a linear actuator positioned to apply a force to the weighing plate; a calibration force sensor positioned to measure the force applied by the linear actuator; and a control unit operatively communicating with the operational force sensors, the linear actuator, and the calibration force sensor, the control unit being configured to cause the linear actuator to apply a force to the weighing plate, compare the resulting outputs from the operational force sensors and the calibration force sensors, and determine a calibration factor based on the comparison for offsetting future outputs from the operational force sensors.

[0144] In the 106th aspect of this disclosure, which can be combined with any other aspect or part thereof, the operating force sensor is positioned at least substantially equidistant from the center of mass of the weighing plate.

[0145] In the 107th aspect of this disclosure, which can be combined with any other aspect or part thereof, the calibrated force sensor is positioned at least substantially at the center of mass of the weighing plate.

[0146] In the 108th aspect of this disclosure, which may be combined with any other aspect or part thereof, the linear actuator includes a motor and a lead screw or a linear stepper motor.

[0147] In the 109th aspect of this disclosure, which may be combined with any other aspect or part thereof, the linear actuator is positioned between the calibration force sensor and the weighing plate.

[0148] In the 110th aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to sum the output obtained from the operating force sensor for comparison with the output obtained from the calibrating force sensor.

[0149] In the 111th aspect of this disclosure, which may be combined with any other aspect or part thereof, a calibration factor for offsetting future outputs from the operating force sensor is applied to the sum of future outputs from the operating force sensor.

[0150] In the 112th aspect of this disclosure, which may be combined with any other aspect or part thereof, the calibration factor comprises the sum of the outputs obtained from calibrating the force sensor and the outputs obtained from operating the force sensor.

[0151] In the 113th aspect of this disclosure, which may be combined with any other aspect or part thereof, the linear actuator is mechanically connected to the weighing plate, and wherein the control unit is configured to cause the linear actuator to apply a pulling force to the weighing plate.

[0152] In the 114th aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to cause a linear actuator to apply a force to the weighing plate before the container is placed on the weighing plate.

[0153] In the 115th aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to cause a linear actuator to apply a force to the weighing plate during treatment, while the container is supported by the weighing plate.

[0154] In the 116th aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is operatively connected to the pump actuator, and wherein at least the operating duration of the pump actuator is controlled by an offset output from an operating force sensor.

[0155] In the 117th aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to cause the linear actuator to not supply force during the duration of operation.

[0156] In the 118th aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to use two or more offset outputs from an operating force sensor to determine mass or volumetric flow rate during treatment.

[0157] In a 119th aspect of this disclosure, which may be combined with any other aspect or part thereof, a dialysis system includes: a disposable kit including a pumping section and at least one container; and a dialysis machine including a pump actuator operable with the pumping section to pump dialysis fluid to and / or from at least one supply container, a weighing plate positioned to support at least one container, a plurality of operational force sensors positioned to support the weighing plate, a linear actuator positioned to apply a force to the weighing plate, a calibration force sensor positioned to measure the force applied by the linear actuator, and a control unit operatively communicating with the operational force sensors, the linear actuator, and the calibration force sensor, the control unit being configured to cause the linear actuator to apply a force to the weighing plate, compare the resulting outputs from the operational force sensors and the calibration force sensor, and determine a calibration factor based on the comparison for offsetting future outputs from the operational force sensors.

[0158] In a first 120th aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to sum the output obtained from the operating force sensor for comparison with the output obtained from the calibrating force sensor.

[0159] In a first twenty-one aspect of this disclosure, which may be combined with any other aspect or part thereof, a calibration factor for offsetting the obtained output from the operating force sensor is applied to the sum of the obtained outputs of the operating force sensor.

[0160] In a first 122nd aspect of this disclosure, which may be combined with any other aspect or part thereof, the at least one container includes at least one supply container, a pump actuator is operable with a pumping section to pump fresh dialysate from the at least one supply container, and a control unit is configured to determine the amount of fresh dialysate delivered using at least two offset outputs from an operating force sensor.

[0161] In a first 123 aspect of this disclosure, which may be combined with any other aspect or part thereof, the at least one container includes at least one discharge container, a pump actuator is operable in conjunction with a pumping section to pump used dialysate to the at least one discharge container, and a control unit is configured to determine the amount of used dialysate delivered using at least two offset outputs from an operating force sensor.

[0162] In the first 124th aspect of this disclosure, which may be combined with any other aspect or part thereof, the control unit is configured to use at least two offset outputs from an operating force sensor to determine the amount of fresh dialysis fluid delivered to the patient or the amount of used dialysis fluid removed from the patient.

[0163] In the 125th aspect of this disclosure, in conjunction with Figures 1 to 13 Any one or more of the features, functions, and alternatives described in the text can be combined with Figures 1 to 13 Any features, functions, and alternatives described in any other diagram and / or any combination of aspects listed herein.

[0164] Therefore, the advantage of this disclosure is that it provides a precise APD system using a relatively simple and cost-effective peristaltic pump.

[0165] Another advantage of this disclosure is that it provides an APD system that eliminates certain sealing problems present in known APD systems.

[0166] Another advantage of this disclosure is that it provides an APD pump drive system that eliminates the bulky pneumatic equipment associated with certain APD systems.

[0167] Another advantage of this disclosure is that it provides an APD pump drive system that reduces noise compared to pneumatic systems.

[0168] Another advantage of this disclosure is that it provides an APD system for managing peritoneal dialysis fluid flow within safe and comfortable patient pressure limits.

[0169] Another advantage of this disclosure is that it provides an APD system with a simplified disposable kit.

[0170] Another advantage of this disclosure is that it provides an APD system with accurate pressure and weight sensing.

[0171] Furthermore, one advantage of this disclosure is that it provides an APD system that simplifies the removal of used dialysis fluid into the patient's house drain.

[0172] Additional features and advantages are described in the following detailed description and accompanying drawings, and will become apparent from them. The features and advantages described herein are not exhaustive, and in particular, many additional features and advantages will be apparent to those skilled in the art based on the drawings and description. Furthermore, no particular embodiment need to possess all the advantages listed herein, and it is clearly conceivable that individual claims may be made to various advantageous embodiments. In addition, it should be noted that the language used in this specification has been chosen primarily for readability and guidance purposes, and not to limit the scope of the subject matter of the invention. Attached Figure Description

[0173] Figure 1 This is a perspective view of one embodiment of the system, related recycling machine, and disposable kit disclosed herein.

[0174] Figure 2 This is a perspective view of one embodiment of the actuation surface of the circulating machine disclosed herein.

[0175] Figure 3 This is a perspective view of one embodiment of the automatic loading structure and related functions of a peristaltic pump pipeline.

[0176] Figure 4 This is a front view of one embodiment of the pinch valve disclosed herein.

[0177] Figure 5A and Figure 5B These are, respectively, a front view and a cross-sectional view of an embodiment of the spring-loaded end-actuator valve plunger of this disclosure.

[0178] Figure 6 This is a front view of one side of an embodiment of the disposable cartridge of this disclosure, which is adjacent to the actuating surface of the recycling machine.

[0179] Figure 7 It is along Figure 6 The line VII-VII in the figure is a perspective view of an embodiment of the valve seat of this disclosure.

[0180] Figure 8 This is a front view of one side of an embodiment of the disposable cartridge of this disclosure, viewed from the outside of the recycling machine when the disposable cartridge is loaded for operation.

[0181] Figure 9 This is a perspective view of the operating side of an embodiment of the disposable cartridge of this disclosure, showing how the fluid path and valve seat are formed.

[0182] Figure 10 The document includes perspective views and elevation cross-sectional views illustrating several alternative embodiments of the valve seat of this disclosure.

[0183] Figure 11 This is a cross-sectional front view showing one embodiment of connecting the pressure sensor and the pressure sensor chamber of this disclosure.

[0184] Figure 12 It is a graph showing the relationship between the pressure sensor output and temperature, which is used to determine the temperature scaling factor of the pressure sensing scaling or offset equation of this disclosure.

[0185] Figure 13 This is a perspective view of one embodiment of a self-calibrating weighing scale that can be used with the systems and cyclic machines disclosed herein. Detailed Implementation

[0186] System Overview

[0187] Now refer to the attached diagram, especially the reference... Figure 1 One embodiment of system 10 includes an automated peritoneal dialysis (“APD”) circulation machine 20 having a housing 22. In one embodiment, circulation machine 20 uses a peristaltic pump for delivery, and circulation machine 20 operates a disposable kit 120. All rigid and flexible tubing portions of the disposable kit 120 may be made of one or more plastics, such as polyvinyl chloride (“PVC”), or non-PVC materials such as polyethylene (“PE”), polyurethane (“PU”), or polycarbonate (“PC”). The housing 22 of circulation machine 20 may be made of any of the aforementioned plastics and / or of metals (e.g., stainless steel, steel, and / or aluminum).

[0188] In the illustrated embodiment, housing 22 is provided with a hinged door 24 having a series of holes or slots 26a, 26b, 26c, 26d, and 26e, which respectively allow the conduits 122a to 122e of the disposable kit 120 to extend from the interior of housing 22 to the exterior of housing 22. Although shown as elongated slots, openings 26a to 26e can alternatively be holes. However, slots 26a to 26e are advantageous because they allow the door 22 to be opened hingedly without placing the conduits 122a to 122e under excessive tension. In one embodiment, the conduits 122a to 122e are pre-connected to a disposable pump cartridge as shown below and are sterilized. The distal ends of the conduits 122a to 122e are removed from the sterilized cap during treatment setup and inserted into containers or bags 124a to 124d of the disposable kit 120 (conduit 122e is the patient conduit). Container or bag 124a can be an expulsion container or bag. Containers or bags 124b and 124c may be primary fresh dialysis fluid supply containers or bags. Container 124d may be a last-fill container or bag that holds a different formulation of fresh dialysis fluid, such as two to three liters of icodextrin, which is formulated to remain in the patient's peritoneal cavity after the patient is disconnected from the disposable kit 120.

[0189] In the illustrated embodiment, door 24 is vertically positioned, thus holding the disposable cartridges of kit 120 vertically within the housing 22 of the circulation machine 20 and abutting against the actuating surface of the housing. Door 24 is located near the user interface portion of the circulation machine 20, which includes a control unit 50 having one or more processors 52, one or more memories 54, and a video controller 56 connecting the one or more processors 52 and one or more memories 54 to a user interface 58. The user interface 58 may include a touchscreen and / or electromechanical buttons, such as membrane switches for inputting user commands and providing instructions, alarms, and warnings. Providing the user interface 58 next to door 24 of housing 22 allows patients or other users to generally interact with a surface of machine 20 for inputting commands, receiving data, and loading / unloading disposable cartridges. User interface 58 may alternatively or additionally be a remote user interface, such as via a tablet or smartphone. Control unit 50 may also include a transceiver and a wired or wireless connection to a network (not shown), such as the Internet, for transmitting treatment data to a doctor's or clinician's server connected to the doctor's or clinician's computer, and receiving prescription instructions / changes from the doctor's or clinician's server connected to the doctor's or clinician's computer. Data sent to the doctor's or clinician's computer may be analyzed and / or converted into other data useful for analysis or used to form other data useful for analysis. Alternatively or additionally, this data conversion is performed at control unit 50 of the circulation machine 20.

[0190] Figure 1 The system 10 shown in one embodiment also includes a bag holder 40 for multiple purposes. The bag holder 40 is sized so that the circulation machine 20 can be stored inside the 40 when not in use. In the illustrated embodiment, the bag holder 40 includes a rotatably hinged handle 42 that allows a user to transport the 40 containing the circulation machine 20. Figure 1 As shown, the bag holder cover 40 is also sized such that when the circulation machine 20 is in use, the bag holder cover can be positioned on top of the circulation machine (in one embodiment, on top of the weighing plate, as discussed in detail below). The bag holder holds multiple containers or bags 124a to 124d, such as multiple supply containers 124b to 124d and one or more discharge containers 124a. As shown, the containers or bags are held within the housing 40 and on the outer upper surface of the cover.

[0191] The bag holder shroud 40 may include color-coded markings 44a to 44d at locations for loading containers or bags having tubing extending through slots or openings 26a to 26d into the circulation machine 20, wherein the slots or openings have similar color-coded markings or boundaries. Matching color-coded markings 44a to 44d and slot boundaries make it easy for patients or caregivers to identify which bag and tubing belongs to which location on the bag holder shroud 40. For example, the boundary of marking 44a and slot 26a may be green to indicate discharge tubing 122a and discharge container 124a, and to indicate the desired location for the discharge container. The boundaries of markings 44b and 44c and slots 26b and 26c may be blue to indicate main supply tubing 122b, 122c and supply containers 124b, 124c, and to indicate the desired location for the supply container. The boundaries of marking 44d and slot 26d can be red to indicate the last-fill pipeline 122d and the last-fill container 124d, and to indicate the desired location for the last-fill container.

[0192] Drain / Clear

[0193] It is conceivable that the supply containers or bags (e.g., main supply containers or bags 124b and 124c) could later be used as discharge containers or bags to reduce overall one-time costs. For example, suppose that at the start of treatment, the patient's body is filled with effluent. This effluent is initially discharged from the patient and delivered to an initially empty discharge container 124a. A first patient filler is then delivered to the patient from a first main supply container 124b and, after a specified residence period, to the same discharge container 124a (or possibly to a different discharge container, depending on the size of one or more discharge containers). In one embodiment, discharge container 124a, along with main supply containers 124b and 124c, are larger six-liter containers to hold fresh and used dialysis fluid for multiple cycles. One or more discharge containers 124a are used to receive effluent until the first supply container 124b is emptied, after which the first supply container receives effluent following a residence period using PD fluid supplied from a second supply container 124c. The first supply container 124b is used to receive patient effluent and may undergo multiple filling, retention, and drainage cycles until the second supply container 124c is empty. At this point, the patient can receive the final filler of different formulations of peritoneal dialysis fluid from the final filler container 124d, which remains in the patient until the next night's treatment or possibly until the midday replacement. If the second supply container 124c is empty at the end of treatment, it can be used as an initial empty drain container at the start of the next treatment, further reducing one-time waste and costs.

[0194] In one example, containers 124a to 124d can be used as follows, where the patient is initially full:

[0195] Initial discharge → Discharge container 124a

[0196] Supply container 124b → First filling → Discharge container 124a

[0197] Supply container 124b → Second filling → Discharge container 124a

[0198] Supply container 124c → Third filling → Supply container 124b

[0199] Supply container 124c → Fourth filling → Supply container 124b

[0200] Finally fill container 124d - final filling

[0201] In one example, containers 124a through 124d can be used as follows, where the patient is initially empty:

[0202] Supply container 124b → First filling → Discharge container 124a

[0203] Supply container 124b → Second filling → Discharge container 124a

[0204] Supply container 124c → Third filling → Supply container 124b

[0205] Supply container 124c → Fourth filling → Supply container 124b

[0206] Finally fill container 124d - final filling

[0207] At the end of treatment, multiple containers or bags (e.g., containers 124a, 124b) are filled with exudate. Additionally, the remaining supply container 124c can hold any residual fresh dialysis fluid. To prevent the patient or caregiver from having to transport a full discharge bag to a house drain, such as a toilet, sink, or bathtub, the control unit 50 of the circulation machine 20 is programmed to prompt the user to remove the patient tubing 122e from the patient transfer kit and to transport the distal end of the patient tubing 122e to the house drain. If needed, a reusable extension tubing 122f can be connected to the distal end of the patient tubing 122e to reach the house drain. The patient or caregiver then presses the drain button on user interface 58, at which point the circulation machine 20 actuates a pump actuator, such as a peristaltic pump actuator, in one direction to draw used dialysis fluid or effluent from each drain container 124a, 124b (one or more of which may be a previous supply container) and pumps the used dialysis fluid through patient line 122e (and extension line 122f, if needed) to the house drain. Residual fresh dialysis fluid is removed from supply container 124c in the same manner. In one embodiment, the drain button is displayed only when needed at the end of treatment, for example via a touchscreen display. Alternatively, the drain button may be a membrane switch, which is only activated when needed at the end of treatment. Furthermore, regardless of the button type, the drain button is only displayed and / or activated after the patient or caregiver presses a confirmation button provided by user interface 58 in response to a prompt from the user interface prompting the patient or caregiver to confirm that patient lines 122e / 122f have flowed to the house drain.

[0208] The control unit 50 of the circulation machine 20 detects when each discharge container 124a, 124b is empty (e.g., via a weighing scale and / or pressure sensor operating with the pressure chamber of the disposable cartridge, as discussed in detail below) and automatically switches valve actuators, such as pinch valve actuators, to sequence the discharge containers 124a, 124b (and supply container 124c, if necessary) until each is empty. Specifically, the circulation machine 20 includes a patient valve actuator operating with a patient valve seat provided by the disposable kit 120, and a discharge valve actuator operating with a discharge valve seat provided by the disposable kit, wherein the control unit 50 is configured to allow flow through the discharge valve seat and patient valve seat by the patient valve actuator to pump used dialysis fluid from the discharge container through the patient line to the house drain. It should be understood that multiple discharge containers (one or more of which may be previous supply containers) may be discharged simultaneously for the same duration or overlapping durations, for example, to save time.

[0209] It is also conceivable that the control unit 50 would locate any remaining fresh dialysis fluid in any remaining supply containers (e.g., containers 124c and 124d) and cause the pump actuator to pump the remaining fresh dialysis fluid through the patient line to the house drain. In this way, once the patient is disconnected from the patient line 122e and presses the drain button, the patient can assume that all the fresh and used dialysis fluid has been pumped to the house drain and is therefore free to begin his or her day.

[0210] It should be understood that although system 10 is described in this section as pumping effluent or remaining fresh dialysis fluid to the house drain, in alternative embodiments, control unit 50 may pump any remaining fluid (fresh or used) from any of containers 124a to 124d to any other containers 124a to 124d. In one embodiment, after treatment, when the patient is disconnected from patient line 122e, the patient places the distal end of the patient line in an infusion retainer (not shown) located on housing 22 of circulation machine 20 and confirms this action at user interface 58. The distal end of patient line 122e remains open to the atmosphere. Control unit 50 then runs a sequence in which all fluid currently present in patient line 122e is pumped to the desired destination containers 124a to 124d, such that patient line 122e is completely or nearly completely filled with air. Then, control unit 50 moves any dialysis fluid (fresh or used) from any containers 124a to 124d to be pumped via peristaltic pump actuator 60, which rotates a known number of strokes in the patient filling direction to push a certain amount of dialysis fluid through the embedded fluid heating path 144 and into the safety section of the patient line 122e, preventing fluid from overflowing from the end of the patient line. Control unit 50 then reverses the direction of peristaltic pump actuator 60 to rotate a known number of strokes in the patient discharge direction and changes the valve state of the relevant valve actuator to push that amount of fluid through the safety section of the patient line 122e and the embedded fluid heating path 144 to the desired destination containers 124a to 124d. Control unit 50 then repeats the pumping and reverse pumping actions until the desired amount of fresh or used dialysis fluid has moved from the desired source containers 124a to 124d to the desired destination containers 124a to 124d.

[0211] Automatic loader

[0212] Now for reference Figure 2 An embodiment of the actuation surface 30 of the circulation machine 32 is shown. Figure 1 The actuating surface 30 is hidden behind the door 24. When the door 24 is opened, as... Figure 2 The actuating surface 30 shown is exposed. Figure 2The label "Top," "Bottom," "User Interface," and "Patient End" are provided to indicate the actuation surface 30 in... Figure 1 How to orient it. In the illustrated embodiment, the actuating surface 30 includes a heater 32, such as a resistance plate that heats the embedded fluid heating path provided to the disposable cartridge shown below. The actuating surface 30 also includes a plurality of valve actuators 34a to 34e, including a discharge line valve actuator 34a, main supply line valve actuators 34b and 34c, a final fill line valve actuator 34d, and a patient line valve actuator 34e. Embodiments of valve actuators 34a to 34e are described in detail below. The actuating surface 30 also includes a plurality of pressure sensors, including a patient pressure sensor 36a and a pump pressure sensor 36b. Embodiments of pressure sensors 36a and 36b are also shown in detail below. At least one temperature sensor 38, such as a thermocouple or a thermistor, is also provided. Figure 2 The control unit 50, schematically shown, controls the heater 32 and valve actuators 34a to 34e, and receives inputs from pressure sensors 36a, 36b and temperature sensor 38.

[0213] Figure 2 A peristaltic pump actuator 60, under the control of control unit 50, is located on and extends behind the actuation surface 30 of the circulation machine 20. The pump actuator 60 may include a pump head 62 located on the actuation surface 30 and a drive or motor 64 located behind the actuation surface 30. The disposable cartridge includes a peristaltic pump tube, which the user guides above the pump head 62 of the peristaltic pump actuator 60 when loading the cartridge. In operation, the peristaltic pump actuator 60 compresses the peristaltic pump tube against a raceway 66 at multiple points. The operational proximity of the raceway 66 to the peristaltic pump actuator 60 would make tube loading difficult. Therefore, the circulation machine 20 provides a movable raceway 66 that, when a patient or caregiver opens the door 24 of the circulation machine 20 to load the disposable cartridge, translates, for example via a linkage (not shown), to not obstruct the peristaltic pump actuator. After the cartridge is loaded, closing the circulation door 24 causes the movable roller 66 to translate, for example via a linkage, into an operable position directly adjacent to the peristaltic pump tubing. In an alternative embodiment, a motor and lead screw assembly or linear actuator (e.g., a linear stepper motor, not shown) is provided to automatically translate the roller 66 to obstruct the peristaltic pump actuator 60 when the patient or caregiver opens the door 24 to load the cartridge, and to automatically translate the roller 66 to the operable position when the door 24 is closed. In yet another alternative embodiment, a motor and lead screw assembly or linear actuator (e.g., a linear stepper motor, not shown) is provided, but the patient or caregiver instead presses one or more buttons on the user interface 58 to translate the roller 66 to an unobstructed or operable position.

[0214] In one embodiment, raceway 66 is mounted to a block or member 70 that is translatable over actuation surface 30 toward and away from the peristaltic pump actuator 60. In addition to the translational movement of member 70 (and raceway 66), the movable raceway 66 is also rotatable about a pivot 72 located at one end 66a of raceway 66, wherein the pivot 72 is mounted to the translational member 70. The other end 66b of raceway 66 is spring-loaded via a spring 74 (e.g., a compression spring) defined between raceway end 66b and member 70. In the illustrated embodiment, spring 74 is inserted into bolt 76, which extends through raceway end 66b and screws into member 70. Bolt 76 includes a head 76h that sets the end of the spring travel of raceway 66, wherein the end of the travel can be adjusted in or out by rotating bolt 76 clockwise or counterclockwise, respectively. In the illustrated embodiment, after component 76 has translated toward peristaltic pump actuator 60, spring 74 pushes and inserts raceway 66 about pivot 72 into the desired operating position around the peristaltic pump tubing. Pivoting raceway 66 absorbs or allows variations due to tubing tolerances and also provides a suppressive effect that helps reduce noise.

[0215] Figure 2 and Figure 3 The diagram illustrates the sliding of a member 70 and a raceway 66 along a linear track 68, which is formed or disposed along an actuating surface 30. The member 70 includes a track receiver (not visible) on its underside, the track receiver being sized to mate with and operate with the linear track 68. In one embodiment, the receiver interacts with the linear track 68, for example via a tongue-and-groove engagement, such that the linear track 68 holds the member 70 and the raceway 66 in a slidably engaged along the actuating surface 30. Alternatively or additionally, Figure 3 An elongated groove 78 is shown to be formed in the member 70. The elongated groove 78 receives bolts that can be loosely tightened so that the member 70 and the raceway 66 can slide along the actuating surface 30 while still remaining on the surface.

[0216] Figure 3 Part IIIA shows the peristaltic pump tube 126 of the disposable kit 120 when it is about to be loaded. The component 70 and the raceway 66 are in a fully retracted or unobstructed position. Figure 3 Part IIIB shows the peristaltic pump tube 126 in an operable position with its extension or placement near the pump head 62 of the peristaltic pump actuator 60. The component 70 and raceway 66 are again in a fully retracted or unobstructed position. Figure 3 Part IIIC shows that component 70 and raceway 66 have been translated into an operable position relative to pump head 62 and peristaltic pumping tube 126 of peristaltic pump actuator 60.

[0217] As mentioned above, a purely mechanical linkage (not shown) can be provided to pull the component 70 and the raceway 66 into place. Figure 3 The complete retraction or non-impeded position of portions IIIA and IIIB, for example, where the linkage is actuated via opening door 24. The linkage pushes member 70 and raceway 66 in... Figure 3 The operable position of part IIIC, for example, in which the linkage is actuated via closing door 24. Alternatively, a motor mechanism, such as a linear actuator or motor and lead screw, is provided to automatically (i) pull member 70 and raceway 66 in when door 24 is opened. Figure 3 (ii) When door 24 is closed, the member 70 and roller 66 are pushed in. Figure 3 The operable position of part IIIC. Alternatively, if it is desired that the actuating surface 30 be accessible when the member 70 and raceway 66 are in the operable position, a button can be provided on the user interface 58 to actuate the actuator, for example, to retract and extend the member 70 and raceway 66, or perhaps only after they are automatically pulled into the fully retracted position when the door 24 is opened, to extend the member 70 and raceway 66 to the operable position. The control unit 50 can be programmed to perform any such sequence.

[0218] like Figure 3 As shown in the fully retracted sections IIIA and IIIB, member 70 includes a base 70b that defines an arc whose radius at least substantially matches the radius of raceway 66. It is conceivable that the head 76h of bolt 76 provides a stop that is positioned (e.g., by screwing bolt 76 into or out of member 70) to prevent pivoting of raceway 66 caused by spring 74 when the radius of raceway 66 at least substantially reaches and thus matches the radius of the arc of base 70b. As mentioned above, raceway 66 is movable, primarily for ease of loading. A second benefit of translational movement is the adjustment of raceway position to optimize pipe variability. Pivoting via pivot 72 and spring 74 helps absorb pipe tolerances and provides a suppressive effect that helps reduce noise. It should be understood that although spring 74 is shown as a compression spring, this spring could alternatively be a tension spring or other type of spring.

[0219] Spring end effector

[0220] Now for reference Figure 4 , Figure 5A and Figure 5BEmbodiments of any or all of the pinch valve actuators 34a to 34e are shown. A disposable cartridge 130 (e.g., injection- or blow-molded plastic) is provided with valve seats 132a to 132e, which respectively receive pinch valve actuators 34a to 34e to block or enclose the fluid path 134 provided by the disposable cartridge. Figure 4 In this configuration, the disposable box 130 is sealed, for example by ultrasonic welding, heat sealing, and / or solvent bonding, and covered by a flexible sheet 136 (e.g., flexible plastic). Parts of the pinch valve actuators 34a to 34e are pressed into the corresponding valve seats 132a to 132e to close the corresponding fluid path 134. The pinch valve actuators 34a to 34e retract to open the corresponding fluid path 134. Figure 4 As shown, openings in valve seats 132a-132e extend through the rigid body 138 of the disposable box 130 and through ports 140a-140e extending in the opposite direction from the valve seats. Corresponding conduits or tubes 122a-122e are respectively sealingly connected (e.g., ultrasonically welded, heat-sealed, and / or solvent-bonded) to ports 140a-140e. Conduits or tubes 122a-122e extend from the disposable box 130 through corresponding slots or openings 26a-26e through a door 24, as... Figure 1 As shown in the image.

[0221] like Figure 4 As shown, each of the pinch valves 34a to 34e is driven by a linear actuator 80, which can be any suitable type of linear actuator, such as a linear stepper motor, which, under the control of the control unit 50, provides the necessary stroke (e.g., up to 10 mm) and the required amount of pressure to close the cartridge sheet (e.g., 30 to 60 Newtons (“N”) or less). In the illustrated embodiment, the linear actuator 80 is mounted to the inner wall 46 or other internal structure within the housing 22 of the circulation machine 20 such that a valve plunger 84, connected to the output shaft 82 of the linear actuator 80, extends through a hole 30h in the actuation surface 30 to precisely contact a flexible valve diaphragm 48 (e.g., flexible silicone), which is bolted into place against the actuation surface 30. The linear actuator 80 drives the valve plunger 84 to press the flexible diaphragm 48 and a portion of the cartridge sheet 136 against the corresponding cartridge valve seats 132a to 132e. The linear actuator 80 retracts the valve plunger 84 to allow the sheet to be removed from the corresponding box valve seats 132a to 132e, for example, by its own elasticity and positive fluid pressure.

[0222] like Figure 5A and Figure 5B As shown, in one embodiment, the valve plunger 84 includes a proximal actuator 86 coupled to a linear actuator 80 and a distal actuator 90 slidably coupled to the proximal actuator 86. Figure 5BAs shown, the proximal actuator 86 includes a larger diameter portion 86a and a smaller diameter portion 86b. The distal actuator 90 includes or defines a cylindrical opening 92 that slidably receives the smaller diameter portion 86b of the proximal actuator 86. In the illustrated embodiment, a spring 98 is positioned between a step 86c transitioning between the larger diameter portion 86a and the smaller diameter portion 86b and the proximal edge 90p of the distal actuator 90. The spring 98 extends thereon and is thus constrained by the smaller diameter portion 86b of the proximal actuator 86. Figure 5A and Figure 5B It is shown that the outer diameter of the distal actuator 90 can be at least substantially equal to the outer diameter of the larger diameter portion 86a of the proximal actuator 86.

[0223] One of the proximal actuator 86 or the distal actuator 90 defines at least one recess, and the other of the proximal actuator or the distal actuator includes at least one spring arm that mechanically engages (e.g., snap-fits) into said at least one recess to slidably attach the end effectors together. In the illustrated embodiment, the proximal actuator 86 defines at least one recess 88, while the distal actuator 90 includes or defines a plurality of spring arms 94a, 94b...94n that mechanically engage (e.g., snap-fits) into at least one recess 88. If it is desired that the distal actuator 90 does not rotate relative to the proximal actuator 86, a separate recess 88 may be defined for each spring arm 94a, 94b...94n. If this is not critical, a single annular recess 88 may be provided instead. In any case, the length of the at least one recess 88 is dimensioned to provide a travel length of the distal actuator 90 relative to the proximal actuator 86 that is equal to or greater than the uncompressed length of the spring 98.

[0224] Spring 98 can be a wave spring or a compression spring. An acceptable stroke length for spring 98 is 2.9 mm. In one embodiment, spring 98 is configured to provide a sealing force of 25 N required to properly seal the box sheet 136 against valve seats 132a to 132e after a compression stroke of approximately 1.4 mm. Spring 98 can apply a force of up to 51 N over its body length, wherein the linear actuator 80 is selected to have at least slightly higher peak force.

[0225] Spring 98 is positioned to bias the distal actuator 90 outward relative to the proximal actuator 86. The variable distance provided by spring 98 allows pinch valves 34a to 34e to initially contact the cartridge sheet 136 (via flexible diaphragm 48) with a small closing force, which steadily increases as spring 98 is compressed. Flexible diaphragm 48 is fixed to actuation surface 30 to cover the end of the distal actuator 90. When spring 98 is fully compressed, cartridge sheet 136 and valve seats 132a to 132e bear the full closing force of linear actuator 80 and spring 98. Spring 198 accordingly provides a force damper, which helps protect flexible diaphragm 48 during multiple treatments and cartridge sheet 136 during a single treatment. Spring 98 also helps accommodate variations due to tolerances of disposable cartridge 130 and its loading, and may also allow for smaller or less expensive linear actuators 80.

[0226] Disposable box / valve seat

[0227] Now for reference Figures 6 to 10 In the illustrated embodiment, the disposable cartridge 130 provides a plurality of valve seats, which may include a patient line valve seat 132e, a first supply line valve seat 132b and a second supply line valve seat 132c, a final filling line valve seat 132d, and a discharge line valve seat 132a. Figure 6 and Figure 9 In the illustrated embodiment, the patient line valve seat 132e is fluidly separated from the first peristaltic tube port 142a via an embedded fluid heating path 144 (e.g., a serpentine path). When the disposable cartridge 130 is installed for operation, the embedded fluid heating path 144 is adjacent to a heater 32, such as a resistance plate heater. Figure 2 As shown in the image. Figure 9 A flexible sheet 136 is shown sealed to a rigid body 138 to cover a fluid heating path 144, thereby allowing heat to be transferred through the thin-walled sheet to the fresh dialysis fluid traveling through the channel.

[0228] Figure 6 and Figure 9As shown, in one embodiment, the first supply line valve seat 132b and the second supply line valve seat 132c, the last fill line valve seat 132d, and the discharge line valve seat 132a are all located within a common pit 146 in fluid communication with the second peristaltic tube port 142b. A peristaltic pump tube 126 is attached (e.g., ultrasonically welded, heat-sealed, and / or solvent-bonded) to the tube ports 142a and 142b. Thus, fresh dialysis fluid can be pumped from any of the supply containers 124b to 124d for the first and second supply line valve seats 132b, 132c, or the last fill line valve seat 132d in a first direction through the common pit 146 and the embedded fluid heating path 144, where the fresh dialysis fluid is heated, and then discharged from the patient line valve seat 132e to the patient. Used dialysis fluid or effluent can be pumped from the patient in the second direction through the patient line valve seat 132e and the embedded fluid heating path 144 (in which the used dialysis fluid is not heated) into the common pit 146, and exit from the discharge line valve seat 132a to the discharge container 124a.

[0229] The shared pit 146 simplifies the fluid path of the box 130. The discharge line valve seat 132a is positioned closest to the peristaltic tube port 142b, so that the used dialysis fluid travels the minimum distance within the pit 146 before reaching the discharge line valve seat. Figure 8 The non-operating side of the disposable cartridge 130 is shown, with an outlet port 140a, supply container ports 140b, 140c, and a last-fill container port 140d extending from the rigid body 138 on the other side of the common pit 146. Furthermore, the outlet port 140a (to which the outlet line 122a is ultrasonically welded, heat-sealed, and / or solvent-bonded) is positioned directly adjacent to the peristaltic tube port 142b to remove used dialysis fluid from the common pit 146 as quickly as possible, minimizing mixing with residual fresh dialysis fluid within the pit. The supply container lines 122b, 122c, the last-fill container line 122d, and the patient line 122e are also ultrasonically welded, heat-sealed, and / or solvent-bonded to the supply container ports 140b, 140c, the last-fill container port 140d, and the patient line port 140e, respectively.

[0230] Figure 7 and Figure 10The valve seats 132a to 132e described herein are shown to include a conical sealing surface 152 surrounded by a plurality of displacement ribs 154a to 154f, wherein the displacement ribs extend from the rigid body 138 of the disposable cartridge 130, and wherein at least some of the displacement ribs 154a to 154f are spaced apart by a gap G to prevent or mitigate undesirable clogging of the conical sealing surface 152 by the flexible sheet 136 and to allow fresh or used dialysis fluid to flow through it. The displacement ribs 154a to 154f can be completely separable from each other (see [link to documentation]). Figure 10 Examples XC to XE in the text), or extending from the common column base (see...). Figure 10 Examples XA and XB in the diagram). Displacement ribs 154a to 154f can also be separated from the conical sealing surface 152 (see examples XA and XB in the diagram). Figure 10 Examples XB, XC, and XE in the diagram, or extending from or connecting to the outer edge of the tapered sealing surface (see examples XB, XC, and XE). Figure 10 Examples XA and XD in the diagram). Displacement ribs 154a to 154f help guide the pinch valve plunger 84 toward the center of the valve seats 132a to 132e, while also providing a certain amount of clearance or play between the pinch valve plunger and the valve seats. In one embodiment, the tapered sealing surface 152 tapers to form a funnel shape leading to an opening that allows fresh or used dialysis fluid to flow into or out of the valve seats 132a to 132e. In one embodiment, the opening extends through ports 140a to 140e located on the other side of the rigid body 138 of the disposable cartridge 130. Figure 8 The conical sealing surface 152 may also include or define one or more circular sealing rings 156 that are pressed into the flexible sheet 136 when the flexible sheet is closed by the clamp valves 34a to 34e.

[0231] In one embodiment, a first or patient pressure sensing chamber 150a is located within a disposable cartridge 130, directly adjacent to the patient line valve seat 132e. When the disposable cartridge 130 is loaded, the patient pressure sensing chamber 150a abuts against a first or patient pressure sensor 36a, whose output is sent to the control unit 50 of the circulation machine. The output of the patient pressure sensor 36a can be used to control the positive and negative pumping pressures experienced by the patient to stay within safe pressure limits, such as a positive pressure of 0.21 bar (3 psig) and a negative pressure of -0.10 bar (-1.5 psig). A second or pumping pressure sensing chamber 150b is located within the disposable cartridge 130, between a common pit 146 and a second peristaltic tube port 142b. When the disposable cartridge 130 is loaded, the pumping pressure sensing chamber 150b abuts against a second or pumping pressure sensor 36b, whose output is sent to the control unit 50 of the circulation machine. The output of the pump pressure sensor 36b can be used to detect blockages in the supply and discharge lines and / or empty supply and discharge containers. For example, a positive pressure fluctuation from the pump pressure sensor 36b can indicate a blockage in the discharge line 122a or the patient line 122e. In another example, a negative pressure fluctuation from the pump pressure sensor 36b can indicate (i) a blockage in the patient line 122e or the supply lines 122b to 122d, (ii) an empty supply container 124b, 124c, or the last-fill container 124d during treatment, or (iii) an empty supply container 124b, 124c, the last-fill container 124d, or the discharge container 124a at the end of treatment, while attempting to pump out any remaining fresh or used treatment fluid.

[0232] The disposable cartridge 130 may also include one or more regions 148 that, when installed for operation, are adjacent to thermocouples or other types of temperature sensors 38 that output to the control unit 50. The temperature sensing region 148 may, for example, be positioned directly adjacent to the end of the embedded fluid heating path 144 of the patient pressure sensing chamber 150a, so that the outlet temperature of fresh dialysis fluid to the patient can be monitored and controlled to a desired temperature, such as body temperature or 37°C, and performed, for example, via a proportional, integral, derivative (“PID”) routine executed by the control unit 50 using feedback from the temperature sensor 38. A second temperature sensor and associated cartridge temperature region (not shown) may be positioned to detect the temperature at the inlet of the embedded fluid heating path 144 (if desired), which can also provide useful information for the PID routine.

[0233] Figure 6A disposable cartridge 130 is shown vertically arranged when loaded and abutting an actuating surface 30 for operation, wherein the cartridge includes several features to enhance filling and air treatment. See also... Figure 1 It should be understood that a key feature of the entire system 10 used to prevent air from reaching the patient is that the fresh dialysis fluid supply containers or bags 124b and 124c, as well as the last-fill container or bag 124d, are positioned at a height above the actuated surface behind the door 24 where the disposable cartridge 130 is loaded. Here, air tends to remain in the containers or bags 124b to 124d and is not delivered to the disposable cartridge 130. Although not shown, it is conceivable that a structure is provided within and on top of the bag holder shroud 40, which raises the rear end of each container or bag 124b to 124d relative to the front discharge end of the container. In this way, air tends to migrate toward the rear of the containers 124b to 124d, away from the connection between the bag and the corresponding conduits 122b to 122d.

[0234] It is also conceivable to place an air sensor or detector (not shown), which could be an ultrasonic sensor with a transmitter and receiver pair on either side of the hole or slot 26b to 26d, such as Figure 1 As shown in the diagram. An air sensor or detector outputs to a control unit 50, which monitors their output signals. If air is detected, the control unit 50 (i) stops the peristaltic pump actuator 60 from pumping further toward the patient, and (ii) shuts off... Figure 6 The corresponding supply valve seats 132b to 132d shown, (iii) open the discharge valve seat 132a, and (iv) reverse the peristaltic pump actuator 60 to force the air-entrained dialysis fluid into the discharge line 122a and the discharge container 124a.

[0235] Figure 6 The discharge valve seat 132a is shown to be positioned above the supply valve seats 132b to 132d in height to facilitate air migration toward the discharge valve seat. Additionally, the top of the common pit 146 is provided with a ramp 146r to guide air upward toward the discharge valve seat 132a. Figure 6 It is also shown that the pump pressure sensing chamber 150b has an inlet below the top of the ramp 146r, which facilitates air to float upward from the pump pressure sensing chamber 150b toward the discharge valve seat 132a. Figure 6 The patient pressure sensing container 150a and the pump pressure sensing container 150b are also shown with their outlets pointing upwards at a relatively high position, causing air to tend to leave the chamber, in order to help the accuracy of pressure measurements of fresh and used dialysis fluid.

[0236] To aid perfusion, a serpentine fluid heating path 144 is wound upwards to facilitate air exiting the disposable cartridge 130 and reaching the atmosphere via the patient line valve seat 132e and patient line 122e during perfusion. When the disposable cartridge 130 is loaded for operation, the patient line valve seat 132e is positioned at a relatively high elevation, similar to the discharge line valve seat 132a. During perfusion, the distal end of the patient line 122e is held in an perfusion retainer (not shown) located on the housing 22 of the circulation machine 20. An additional air detector or sensor (not shown) (e.g., an ultrasonic sensor) outputting to the control unit 50 can be incorporated into the perfusion retainer to detect when the patient line 122e is fully perfused with fresh dialysis fluid. It is also conceivable to place an additional air sensor or detector (not shown) for the patient line, which could also be an ultrasonic sensor, with a location... Figure 1 A transmitter and receiver pair is shown on either side of the patient line port or slot 26e. An additional air sensor or detector outputs to a control unit 50, which monitors its output signal. If air is detected in the patient line 122e, the control unit 50 executes the air purging procedures (i) to (iv) just described to push the air back through the fluid heating path 144 to the discharge container or bag 124a.

[0237] pressure sensor

[0238] Now for reference Figure 11 In one embodiment, the circulation machine 20 of system 10 mounts pressure sensors 36a, 36 to or relative to the actuation surface 30 of the circulation machine so as to reside within an aperture 30h in the actuation surface 30, and such that when the disposable cartridge 130 is loaded for operation, the cartridge sheet 136 (which may be polyvinyl chloride (“PVC”) or any other polymer listed herein) is contacted by the pressure sensors 36a, 36b and placed under tension to generate a baseline or preload force Fp measured by the pressure sensors. Figure 11 A possible diameter of the contact head for pressure sensors 36a, 36b, i.e., 10 mm, is shown, which also provides an indication of the size or diameter of the pressure chambers 150a, 150b of the disposable cassette 130. The pressure P of fresh or used dialysis fluid causes the cassette sheet 136 to further shift (or attempt to shift), thereby increasing or decreasing the reaction fluid force Fr acting on the pressure sensors 36a, 36b relative to the baseline or preload force Fp. The force difference between Fr and Fp caused by the positive or negative fluid pressure P is correlated with the actual fluid pressure value via control unit 50, which is used for pressure control as described herein, and can be displayed by user interface 58 and / or stored for evaluation by a remote server computer.

[0239] The pre-tensioning of the sheet 136 by pressure sensors 36a and 36b results in a pressure sensing mechanism with high sensitivity and resolution, but it may be susceptible to temperature sensitivity. Therefore, it is conceivable to program the control unit 50 to compensate for temperature-induced pressure readings. Here, the voltage output (or alternatively current output) from the pressure sensors 36a and 36b is modified by adding an offset component, which is a function of the measured temperature (e.g., using the temperature sensor 38 and temperature sensing area 148 discussed above) multiplied by an empirically determined temperature scaling factor, to form a compensated voltage output, which is then converted into a compensated positive or negative pressure or related to a compensated positive or negative pressure. A suitable scaling or offset algorithm stored in the control unit 50 is as follows:

[0240] V T =V0+gT, where

[0241] V0 is the output from pressure sensors 36a and 36b.

[0242] V T The modified pressure output is continued to be used by control unit 50.

[0243] g is the temperature proportionality coefficient, and

[0244] T is the sensed temperature.

[0245] Figure 12 A graph is shown to determine the temperature scaling factor g used in the scaling or offset algorithm described above. For each of the four curves, the baseline or preload Fp of pressure sensors 36a and 36b is observed during a 30-minute fluid residence period for different temperatures maintained within the range of 15°C to 40°C (typical dialysis fluid temperature). Figure 12 The equations representing each line are shown. Each equation takes the form y = mx + b, where (i)y is the V above. T (ii)b is V0 above, (iii)x is the measured temperature T above, and (iv)m is the scaling factor g above. The m values ​​of each test are averaged to form the scaling factor g used in the scaling or offset algorithm stored in the control unit 50.

[0246] In one embodiment, the control unit 50 is configured to (i) update the compensation algorithm for adjusting the temperature T each time the control unit reads the output from the pressure sensor or (ii) periodically. The control unit 50 is configured to use the modified output V from the pressure sensors 36a, 36b. TFor use in at least one of the following: (a) controlling a medical fluid pump actuator to pump within positive or negative patient pressure limits, (b) determining the status of tubing blockage, and / or (c) determining the status of a fresh or used dialysis fluid container being empty during or after treatment.

[0247] As mentioned above, pre-tensioning of the cassette sheet 136 via pressure sensors 36a, 36b results in a pressure sensing mechanism with high sensitivity and high resolution, but it may also be susceptible to mechanical creep sensitivity. To combat creep sensitivity, in one embodiment, the control unit 50 is programmed to pre-treat the cassette sheet 136 prior to treatment (e.g., during a setup period) to eliminate most of the pressure signal variation due to creep before measurements from pressure sensors 36a, 36b take effect. To this end, after the disposable cassette 130 is infused for treatment, the control unit 50 closes all clamp valves 34a to 34e and then actuates the peristaltic pump actuator 60 to pressurize the interior of the cassette 130 (including the sheet at pressure chambers 150a, 150b) to stretch the cassette sheet. The control unit 50 may be programmed to cause the pump actuator 60 to periodically oscillate the cassette fluid pressure multiple times over a specified duration, and may oscillate in different directions. The upper limit pressure can be, for example, 100% to 150% of the maximum operating pressure set for treatment, where the maximum operating pressure can exceed the patient's pressure limit. For example, the pressures discussed above for perfusion or during drainage clearance can be higher, such as 0.50 bar (7.25 psig) or higher. Pretreatment of the cartridge sheet 136 helps to make the uncompensated pressure readings more accurate, while temperature compensation helps to make the final pressure readings more accurate.

[0248] Force sensor calibration

[0249] Now for reference Figure 13 In one embodiment, the system 10 and circulation machine 20 of this disclosure employ a weighing scale 100 including multiple operational force sensors 102a to 102d to monitor the amount of fresh dialysis fluid delivered to the patient, the amount of used dialysis fluid removed from the patient, and thereby enabling the control unit 50 to calculate the amount of ultrafiltration (“UF”) removed from the patient. The weighing scale and force sensors are advantageous for several reasons. First, the weighing scale 100 is relatively accurate compared to other volumetric measurement techniques. Second, the weighing scale 100 reduces pump costs because the pump actuator 60 can be a relatively simple peristaltic pump actuator, and the disposable portion of the pump can be a simple peristaltic pump tubing 126.

[0250] One disadvantage of using force sensors is calibration. Over time, force sensor readings may become inaccurate, thus requiring recalibration. This circulation machine 20 and associated system 10 provide a weighing scale 100 with multiple force sensors 102a to 102d and an onboard structure 110, and provide related methods for calibrating the weighing scale 100. In one embodiment, the weighing scale 100 includes a weighing plate 104 located at the top of the circulation machine 20, which supports the bag holder shroud 40 and the weight of each solution and discharge container 124a to 124d, as well as the associated fresh and used dialysis fluid. The weighing plate 104 and each weighed item on the weighing plate are supported by multiple (e.g., four) force sensors 102a to 102d, which collectively measure the total mass placed on the weighing plate (bag holder shroud 40, containers 124a to 124d, and fluid). In one embodiment, the airborne calibration structure 110 includes a linear actuator 112 (which may be of the same type as a pinch valve, e.g., including a motor and lead screw or a linear stepper motor) and a fifth or calibration force sensor 114 located below the linear actuator 112, wherein the linear actuator 112 includes an actuation output shaft 116 fixed to the weighing plate 104. The actuation output shaft 116 may, for example, extend through a hole formed in the weighing plate 104 and be overlaid on the upper surface of the weighing plate to enable the application of a downward force to the plate. The actuation output shaft 116 may alternatively include a flange bolted to the underside of the weighing plate 104 or slid into a groove formed on the underside of the weighing plate 104, threaded for threaded connection to the underside of the weighing plate 104, or have some alternative mechanical connection to the weighing plate 104.

[0251] In one embodiment, the linear actuator 112 is actuated to apply a pulling or downward force to the weighing plate 104. In one embodiment, this force is applied to the center of mass CM of the weighing plate 104, such as... Figure 13 As shown in the figure. In one embodiment, the force sensors 102a to 102d are each at least substantially equidistant from the center of mass CM, and are spread out to each other with equal x-coordinate distances (e.g., the distance between the contact points of force sensors 102a and 102b is the same as the distance between the contact points of force sensors 102d and 102c) and equal y-coordinate distances (e.g., the distance between the contact points of force sensors 102a and 102d is the same as the distance between the contact points of force sensors 102b and 102c).

[0252] An additional calibration force sensor 114 measures the total tensile or downward force applied by the linear actuator 112, while four operational force sensors 102a to 102d each measure a portion or a quarter of the total force. If the operational force sensors 102a to 102d each perform correctly, the sum of their outputs should equal the total force measured by the calibration force sensor 114. In one example, suppose the linear actuator 112 applies a tensile force of 1000 Newtons (“N”). The calibration force sensor 114 should output 1000 N, while the operational force sensors 102a to 102d should each read 250 Newtons, totaling 1000 N.

[0253] Because the calibration force sensor 114 is not frequently used, a calibration algorithm is applied under the assumption that the output of the calibration force sensor 114 is more accurate than the collective output of the operational force sensors 102a to 102d used in each treatment. Therefore, if a mismatch exists between the readings of the calibration force sensor 114 and the collective outputs of the operational force sensors 102a to 102d during calibration, the control unit 50 using the calibration algorithm scales or offsets the collective outputs of the operational force sensors 102a to 102d to match the readings of the calibration force sensor 114. In the example above, it is assumed that the operational force sensors 102a to 102d actually read a total of 995N instead of 1000N. The readings of the operational force sensors 102a to 102d are correspondingly 0.5% lower. The control unit 50 of the cycler 20 is thus configured to modify the collective outputs of the operational force sensors 102a to 102d during treatment with a calibration factor of 1000 / 995 or 1.005.

[0254] The force sensor calibration routine or algorithm of system 10 is executed on a certain expectation basis, for example, before each treatment begins. For example, control unit 50 uses the offset output pressure from operating force sensors 102a to 102d to control the duration of operation (patient filling or emptying) of pump actuator 60. Control unit 50 is configured such that linear actuator 112 does not supply any force during the duration of this operation. In another example, control unit 50 is configured to use two or more offset outputs from operating force sensors 102a to 102d to determine the mass or volumetric flow rate during treatment. In another example, control unit 50 is configured to use at least two offset outputs from operating force sensors 102a to 102d to determine the amount of fresh dialysis fluid delivered. In yet another example, control unit 50 is configured to use at least two offset outputs from operating force sensors 102a to 102d to determine the amount of used dialysis fluid delivered. In yet another example, the control unit 50 is configured to use at least two offset outputs from the operating force sensors 102a to 102d to determine the amount of fresh dialysis fluid delivered to the patient or the amount of used dialysis fluid removed from the patient.

[0255] It should also be understood that, because many weight values ​​monitored and collected during treatment are weight differences, errors in the collective output of the maneuvering force sensors 102a to 102d tend to self-cancel, assuming the errors do not change during treatment. For example, the mass associated with the patient filling volume (e.g., two liters) is monitored and controlled by the collective output of the maneuvering force sensors 102a to 102d by recording the mass decrease during the patient filling process. The volume and mass associated with patient expulsion can be preset in the control unit 50, for example, by multiplying the filling volume by a coefficient such as 1.3 to account for the patient's UF being moved into the expulsion volume. Alternatively, the volume and mass associated with patient expulsion can be open-ended and controlled by sensing a characteristic rise in negative pressure by pumping the pressure sensing chamber 150b and the associated pressure sensor 36b to indicate that the patient has been substantially expelled and that further expulsion may cause the patient discomfort. In either case, the maneuvering force sensors 102a to 102d sense an increase in weight during the patient expulsion process, which should tend to eliminate any errors in the maneuvering force sensors.

[0256] It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Therefore, these changes and modifications are intended to be covered by the appended claims. For example, while system 10 discloses peristaltic pumping, membrane pumping or volumetric pumping may be used alternatively. Furthermore, while system 10 discloses embedded heating, batch heating may be used alternatively. Additionally, while calibrated load sensing is disclosed in conjunction with supply and discharge containers, calibrated load sensing may be used alternatively with a dialysate preparation unit that pumps one or more weighing containers placed on a weighing plate.

Claims

1. A peritoneal dialysis system, comprising: A circulation machine, the circulation machine including a pump actuator; Disposable kit, the disposable kit comprising: The pumping section is capable of operating together with the pump actuator. The patient tubing is positioned in fluid communication with the pumping section, and A discharge container, which is positioned in fluid communication with the pumping section; A supply container positioned in fluid communication with the pumping portion of the disposable kit; and A control unit, which is operatively in communication with the sensor, is configured to cause the pump actuator to actuate the pumping section in order to: (i) Peritoneal dialysis treatment is performed, in which fresh dialysis fluid is pumped from the supply container to the patient through the patient tubing, and used dialysis fluid is pumped from the patient to the discharge container. (ii) At the end of the peritoneal dialysis treatment, the used dialysis fluid is pumped from the discharge container through the patient line to the house drain. The supply container is subsequently used to receive used dialysis fluid from the patient during peritoneal dialysis treatment, and The control unit is configured to use the output from the sensor to determine when one of the discharge container or the supply container which is subsequently used as the discharge container is empty or substantially empty after its used dialysis fluid has been pumped into the house drain, and thereafter switch to the other of the discharge container or the supply container which is subsequently used as the discharge container to pump its used dialysis fluid into the house drain.

2. The peritoneal dialysis system according to claim 1, wherein, The pump actuator is a peristaltic pump actuator, and the pumping portion of the disposable kit includes a peristaltic pump tube.

3. The peritoneal dialysis system according to claim 1, wherein, The peritoneal dialysis system includes an extension line configured to connect to the patient line to reach the house drain when needed.

4. The peritoneal dialysis system according to claim 3, wherein, The extension pipeline is reusable.

5. The peritoneal dialysis system according to claim 1, wherein, The peritoneal dialysis system includes a user interface that communicates with the control unit, and wherein the user interface is configured to prompt the patient to disconnect the patient tubing and move the patient tubing toward the house drain at the end of the peritoneal dialysis treatment.

6. The peritoneal dialysis system according to claim 1, wherein, The peritoneal dialysis system includes a user interface that communicates with the control unit, and wherein the user interface is configured to provide or enable a drain button at the end of the peritoneal dialysis treatment to initiate the pumping of used dialysis fluid from the drain container through the patient line to the house drain.

7. The peritoneal dialysis system according to claim 6, wherein, The user interface is also configured to require confirmation that the drain line is in fluid communication with the house drain before providing or enabling the drain button.

8. The peritoneal dialysis system according to claim 1, wherein, The circulation machine includes a patient valve actuator that operates with a patient valve seat provided by the disposable kit, and a discharge valve actuator that operates with a discharge valve seat provided by the disposable kit, wherein the control unit is configured to allow the patient valve actuator and the discharge valve actuator to flow through the patient valve seat and the discharge valve seat to pump used dialysis fluid from the discharge container through the patient line to the house drain.

9. The peritoneal dialysis system according to claim 8, wherein, At least one of the patient valve actuator or the discharge valve actuator is a pinch valve actuator.

10. The peritoneal dialysis system according to claim 1, wherein, The sensor is a weight sensor or a pressure sensor.

11. The peritoneal dialysis system according to claim 1, wherein, The control unit is also configured to cause the pump actuator to actuate the pumping portion at the end of the peritoneal dialysis treatment to pump the remaining fresh dialysis fluid from the supply container through the patient line to the house drain.

12. A peritoneal dialysis system (10), comprising: A circulation machine (20) includes a pump actuator (60); A disposable kit (120), the disposable kit (120) comprising: The pumping section (126) is capable of operating together with the pump actuator (60). The patient tubing (122e) is positioned in fluid communication with the pumping section (126), and A first discharge container (124a) is positioned in fluid communication with the pumping section (126); A control unit (50) is configured to actuate the pumping portion of the pump actuator (60) to (i) perform peritoneal dialysis treatment in which fresh dialysis fluid is pumped to the patient through the patient line (122e) and used dialysis fluid is pumped from the patient to the first discharge container (124a), and (ii) at the end of the peritoneal dialysis treatment, used dialysis fluid is pumped from the first discharge container (124a) to the house drain through the patient line (122e). The disposable kit includes a second discharge container (124b) positioned in fluid communication with the pumping portion (126) of the disposable kit (120), wherein the circulation machine (20) includes a sensor operatively communicating with the control unit (50), and wherein the control unit (50) is configured to use the output from the sensor to determine when the first discharge container (124a) is empty or substantially empty after pumping its used dialysate to the house drain, and thereafter switch to the second discharge container (124b) to pump its used dialysate to the house drain.

13. The peritoneal dialysis system (10) according to claim 12, wherein, The sensor is a weight sensor (102a to 102d) or a pressure sensor (36a, 36b).

14. The peritoneal dialysis system (10) according to claim 1, wherein, The discharge container (124a) is a first discharge container, and the peritoneal dialysis system includes a second discharge container (124b) positioned in fluid communication with the pumping portion (126) of the disposable kit (120), wherein the control unit (50) is configured to discharge the first discharge container (124a) and the second discharge container (124b) simultaneously.

15. A peritoneal dialysis system, comprising: A circulation machine, the circulation machine including a pump actuator; Disposable kit, the disposable kit comprising: The pumping section is capable of operating together with the pump actuator. The patient tubing is positioned in fluid communication with the pumping section, and Discharge line, the discharge line being positioned in fluid communication with the pumping section; and The control unit is configured to cause the pump actuator to actuate the pumping section in order to: (i) Peritoneal dialysis treatment is performed, in which fresh dialysis fluid is pumped to the patient through the patient tubing, and used dialysis fluid is pumped from the patient to at least two containers through the discharge tubing, and (ii) At the end of the peritoneal dialysis treatment, the used dialysis fluid is pumped from the container through the drain line and the patient line to the house drain. The patient tubing and the drain tubing are separated by a disposable cartridge of the disposable kit, and at the end of the peritoneal dialysis treatment, the used dialysis fluid is pumped to the house drain via the drain tubing, the disposable cartridge, and the patient tubing. The disposable cartridge includes a pressure sensing chamber positioned to detect pressure changes in a container indicating fluid communication with an empty drain line, and wherein the control unit subsequently causes a switch to drain used dialysis fluid from another container into the house drain at the end of the peritoneal dialysis treatment.

16. The peritoneal dialysis system according to claim 15, wherein, The container is a discharge container, and wherein the discharge container is initially provided as a discharge container or a supply container filled with fresh dialysis fluid.

17. The peritoneal dialysis system according to claim 15, wherein, The circulation machine includes a weighing scale, wherein the discharge container of the at least two containers in fluid communication with the discharge line is positioned to be weighed by the weighing scale, and wherein the control unit uses an output from the weighing scale indicating that the discharge container is empty to induce a switch to discharge used dialysis fluid from a different source to the house drain at the end of the peritoneal dialysis treatment.

18. A peritoneal dialysis system, comprising: A circulation machine, the circulation machine including a pump actuator; Disposable kit, the disposable kit comprising: The pumping section is capable of operating together with the pump actuator. The patient tubing is positioned in fluid communication with the pumping section, and A discharge container, which is positioned in fluid communication with the pumping section; as well as The control unit is configured to cause the pump actuator to actuate the pumping section in order to: (i) Peritoneal dialysis treatment is performed, in which fresh dialysis fluid is pumped to the patient through the patient tubing, and used dialysis fluid is pumped from the patient to the discharge container, and (ii) At the end of the peritoneal dialysis treatment, the used dialysis fluid is pumped from the discharge container to another container through the patient line at least by actuating the pumping portion in a first direction to at least partially fill the patient line with the used dialysis fluid, and then actuating the pumping portion in a second direction to remove the used dialysis fluid from the patient line to the other container.

19. The peritoneal dialysis system according to claim 18, wherein, The other container includes a container positioned in fluid communication with the pumping section.

Images