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.

The specification discloses a portable dialysis machine having a detachable controller unit and base unit with an improved reservoir heating system. The controller unit includes a door having an interior face, a housing with a panel, where the housing and panel define a recessed region configured to receive the interior face of the door, and a manifold receiver fixedly attached to the panel. The base unit has a reservoir with an internal pan and external pan, separated by a space that holds a heating element. The heating element is electrically coupled to electrical contacts attached to the external surface of the external pan.

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.

A medical fluid delivery machine includes a pump interface having an actuation area for delivering positive or negative pressure to a medical fluid handling device; a pressure sensor positioned to measure pressure within the actuation area; a valve positioned to selectively vent the actuation area to atmosphere; and a control unit in signal communication with the pressure sensor and control communication with the valve, the control unit performing a sequence during pumping, wherein (i) application of positive pressure or negative pressure to the actuation area is stopped, the valve is switched to vent the actuation area to atmosphere, then switched to close the actuation area to atmosphere, and at least one pressure signal reading is taken via the pressure sensor, and (ii) a determination is made whether positive pressure or negative pressure to the chamber should be resumed based on the at least one pressure signal reading.

A peritoneal dialysis device includes a disposable tubing set that includes a fill line with a patient access connector at one end and a dialysis fluid receiving end opposite the patient access connector end. The device also includes a fill-side pressure measuring sensor attached at the fill end and forming a disposable component of the tubing set and a patient-side pressure measuring sensor located at the fluid receiving end. The patient-side and fill-side pressure measuring sensors are adapted for measuring pressure in the fill line at the respective ends thereof. The device also includes a controller configured to regulate a rate of flow in the fill line responsively to a signal from the at least the patient-side pressure measuring sensor.

A spectroscopic detection system includes a sensor configured to reflect light of a first wavelength associated with a presence of a reference substance on the sensor and configured to reflect light of a second wavelength associated with a presence of a monitored substance on the sensor, wherein the monitored substance flows to the sensor from a circulating fluid. The spectroscopic detection system further includes a detector that has first and second channels for respectively receiving the light of the first and second wavelengths reflected from the sensor and one or more processors in electrical communication with the detector and configured to identify an excess condition of the monitored substance with respect to the circulating fluid based on a ratio of a second amount of the light of the second wavelength received at the detector to a first amount of the light of the first wavelength received at the detector.