Automated control mechanisms and methods for controlling fluid flow in a hemodialysis apparatus are described. The methods can involve a controller receiving information from a pressure sensor in a control chamber of a reciprocating diaphragm-based blood pump and causing the application of a time-varying pressure waveform on a diaphragm of the blood pump during a fill-stroke of the blood pump. The controller can be configured and programmed to monitor a pressure variation in the control chamber measured by the pressure sensor and to compare the measured pressure variation to a pre-determined value. Based on such comparison, the controller can initiate a procedure to pause or stop a dialysate pump of the hemodialysis apparatus if the magnitude of the measured pressure variation deviates from the pre-determined value.

A method of preserving a sorbent device of a dialysis system, the method comprising—after administering a first dialysis treatment at the dialysis system and before administering a second dialysis treatment at the dialysis system—circulating a fluid through the sorbent device to prevent matter within the sorbent device from solidifying and circulating the fluid through a filter coupled to an outlet of the sorbent device to remove contaminants from the fluid.

A peritoneal dialysis machine that includes a preparator as well as a cycler to form the peritoneal dialysis system. The system delivers purified water into one or more containers with different powders to create a concentrate and then moves this concentrate to a mixing bag to create the peritoneal dialysis fluid (PDF). The cycler then delivers fresh PDF to the patient and removes waste fluid via the drain outlet. A volumetric approach controls the hydraulic flow paths that introduce purified water to the powder concentrates, provide mixing of the concentrate to form the PDF and delivery of the freshly made PDF to the patient. Different configurations of hydraulic flow/pressure generators are provided in the fluid paths to provide optimization of the flow of water through the fluid system to create the correct powder concentrates and subsequent peritoneal dialysis fluid for cycling, for example being provided in a disposable cassette.

A method and a system comprising an integrated water purifying apparatus with a pre-filter circuit including a particle filter and an activated carbon filter arranged to produce pre-treated water; a fluid circuit arranged to receive pre-treated water from the pre-filter circuit, the fluid circuit including an RO-pump and a Reverse Osmosis (RO) device arranged to produce purified water; a heating device arranged to heat purified water from the RO device to a temperature above 65°0 C.; the water purifying apparatus further arranged to heat disinfect the fluid circuit using the heated purified water. The system further comprises a line set connected to the purified water outlet connector at a water line connector of the line set, wherein the line set includes at least one sterile sterilizing grade filter arranged to further filter the purified water.

A peritoneal dialysis system includes first and second concentrate sources in selective fluid communication with a medical fluid pumping cassette, the first and second concentrate sources holding first and second peritoneal dialysis concentrates, respectively; a pump actuator configured to cause the medical fluid pumping cassette to pump the first and second concentrates; and a processor and memory configured to (i) determine a cumulative volume of at least one of the first or second peritoneal dialysis concentrates pumped from the medical fluid pumping cassette by the pump actuator, (ii) compare the cumulative volume to a threshold, and (iii) if the cumulative volume is outside of the threshold, modify a subsequent stroke volume of at least one of the first or second pump chambers actuated by the pump actuator in an attempt to cause an updated cumulative volume for the at least one peritoneal dialysis concentrate to be within the threshold.

A dialysis machine (e.g., a peritoneal dialysis (PD) machine) can include a control unit configured to operate in a hybrid automated mode during a PD treatment. A processor in the control unit is configured to engage a pump during a fill phase of the PD cycle. The volume of fluid (e.g., dialysate) transferred to a patient line during the fill phase is monitored. After a dwell period, the pump is disengaged at the start of a drain phase of the PD cycle. Disengaging the pump can include: configuring valves of a disposable cassette to bypass the pump chambers of a disposable cassette; activating a bypass valve to shunt the patient line to a drain line; or moving a roller assembly of a peristaltic pump. The fluid transferred from the patient line to the drain line is monitored during the drain phase of the PD cycle.

A water purification apparatus (300) capable of being cleaned at a point of care, and methods for cleaning the water purification apparatus (300) at the point of care. The water purification apparatus (300) and the methods provide an efficient use of a heater (302) for heat disinfection the water purification apparatus (300), e.g. by recirculating heated fluid to further heat the fluid. Several different cleaning programs are provided that may be utilized for cleaning different parts of the water purification apparatus (300).

A dialysis machine (e.g., a peritoneal dialysis (PD) machine) can include a safety feature that is used to isolate individual fluid lines attached to a disposable cassette. The PD machine can include an interface for a disposable cassette, a plurality of safety mechanisms, and a processor. A plurality of fluid lines are connected to the disposable cassette, and each safety mechanism corresponds to a particular fluid line in the plurality of fluid lines. The processor is configured to detect a hazard condition, such as a loss of power to the PD machine or leak in the disposable cassette, and activate one or more safety mechanisms to isolate corresponding fluid lines connected to the disposable cassette. In one embodiment, the safety mechanisms are spring-loaded clamping mechanisms configured to compress a distensible tube connected to the fluid line. In another embodiment, the safety mechanisms include relay solenoids and/or check valves.

Dialysis systems are disclosed comprising new fluid flow circuits. Systems may include blood and dialysate flow paths, where the dialysate flow path includes balancing, mixing, and/or directing circuits. Dialysate preparation may be decoupled from patient dialysis. Circuits may be defined within one or more cassettes. The fluid circuit fluid flow paths may be isolated from electrical components. A gas supply in fluid communication with the dialysate flow path and/or the dialyzer able to urge dialysate through the dialyzer and urge blood back to the patient may be included for certain emergency situations. Fluid handling devices, such as pumps, valves, and mixers that to can be actuated using a control fluid may be included. Control fluid may be delivered by an external pump or other device, which may be detachable and/or generally rigid, optionally with a diaphragm dividing the device into first and second compartments.

A method and apparatus for evaluating a condition of a water purification system (40, 110) comprising a water purification apparatus (110) arranged to output purified water through an outlet (128) and through at least one sterilizing grade filter (70a, 70b) of a line set (40) fluidly connected to the outlet (128), the method comprises: monitoring a flow rate (S1) correlated with the flow rate of the purified water flowing through the at least one sterilizing grade filter (70a, 70b); monitoring a pressure (S2) correlated with the pressure of the purified water flowing to the at least one sterilizing grade filter (70a, 70b); and evaluating (S3) a condition of the water purification system based on a relationship between the monitored flow rate and the monitored pressure.