A dialysis system has a module with a dialyzer configured to remove one or more substances from a dialysis solution as it passes through a dialyzer. The module has a fluid line, a sorbent cartridge, and a sodium control system adapted to actively alter a sodium concentration of dialysis solution passing through the fluid line as the dialysis solution exits the sorbent cartridge. The sodium control system has a conductivity sensor that sends a signal indicating the conductivity of the dialysis solution as the dialysis solution exits the sorbent cartridge, the conductivity meter being in communication with the sodium control system, a processor configured to receive the signal from the conductivity sensor, compare the conductivity signal to a threshold value lower than a prescription value, and cause the sodium control system to stop actively altering the sodium concentration if the signal is greater than the threshold value.

A dialysis machine (e.g., a peritoneal dialysis (PD) machine) can include a control unit configured to monitor an amount of fluid withdrawn from a heater bag line during a PD treatment. A processor in the control unit is configured to operate a first pump to draw fluid into a first pump chamber and measure a first fluid volume in the first pump chamber. The processor is further configured to operate the first pump and a second pump to transfer fluid from the first pump chamber to a second pump chamber, measure a second fluid volume in the second pump chamber, and determine a measured fluid volume for a single pump cycle based on the first fluid volume and the second fluid volume. The first fluid volume is correlated to the second fluid volume and, therefore, the multiple independent measurements increase an accuracy of the fluid volume measurement.

A medical infusion fluid handling system, such as an automated peritoneal dialysis system, may be arranged to de-cap and connect one or more lines (such as solution lines) with one or more spikes or other connection ports on a fluid handling cassette. This feature may reduce a likelihood of contamination since no human interaction is required to de-cap and connect the one or more lines and the one or more spikes. For example, the automated peritoneal dialysis system may include a carriage arranged to receive the one or more lines each having a connector end and a cap. The carriage may move along a first direction so as to move the connector ends of the one or more lines along the first direction, and a cap stripper may be arranged to engage with the caps on the the one or more lines on the carriage. The cap stripper may move in a second direction transverse to the first direction, as well as to move with the carriage along the first direction.

The present invention generally relates to hemodialysis and similar dialysis systems, including a variety of systems and methods that would make hemodialysis more efficient, easier, and/or more affordable. One aspect of the invention is generally directed to new fluid circuits for fluid flow. According to one aspect, a blood pump is configured to pump blood to a dialyzer of a hemodialysis apparatus, the blood pump comprising a pneumatically actuated or controlled reciprocating diaphragm pump. In an embodiment, the diaphragm of the pump comprises a flexible membrane formed or molded to generally conform to a curved inner wall of a pumping chamber or control chamber of the pump, wherein the diaphragm is pre-formed or molded to have a control side taking a convex shape, so that any elastic tension on the diaphragm is minimized when fully extended into a control chamber of the pump. In another aspect, a system for monitoring the adequacy of blood flow in a blood line of the hemodialysis apparatus allows a controller to suspend dialysate pumping operations if the adequacy of blood flow in the blood line is sub-optimal, and to present information on a display on the quality of blood flow in the blood line.

A pump cassette comprising an outer flexible membrane covering flowpaths, valve chambers and pump chambers of the cassette is designed to be actuated by a control gasket on a base unit arranged to move designated valve and pump portions of the cassette membrane. The performance of a cassette valve may improved by optimizing the configuration of the valve control region of the control gasket overlying the cassette valve. This may improve both fluid flow through the valve and reduce the amount of vibratory noise associated with opening the valve. The gasket valve control or actuation region is at least partially bounded by a vacuum channel facing the outside of the gasket so that a constant vacuum can be applied between the gasket valve control or actuation region and the adjacent portion of the cassette membrane. An improved version of the vacuum channel comprises a flexible inner wall (contiguous with the valve control region) so that the inner wall flexes or partially collapses away from the cassette valve seat, while still maintaining patency of the vacuum channel during the application of negative pressure on the gasket valve actuation region to open the cassette valve.

A peritoneal dialysis system includes a cycler including a pump actuator, a heater and a heating pan operable with the heater, and a disposable set operable with the cycler. The heating pan includes a sidewall forming a slot. The disposable set includes a pumping cassette and a heater/mixing container. The pumping cassette includes a pump chamber configured to be actuated by the pump actuator. Additionally, the heater/mixing container is in fluid communication with the pumping cassette and is sized to be received at the heating pan. The heater/mixing container includes a port configured such that when the port is slid into the slot of the heater pan sidewall, the port is prevented from rotating about an axis transverse to a direction of flow through the port.

A regenerative peritoneal dialysis system includes a dialysis fluid loop; a filter located in the dialysis fluid loop, a first portion of the dialysis fluid sent to the filter rejected by the filter and returned upstream of the filter, a second portion of the dialysis fluid sent to the filter forming permeate, the permeate being rich in urea; and a urea removing apparatus located in the dialysis fluid loop downstream from the filter to receive the permeate and absorb urea from the permeate.

A disposable cartridge for use in a hemodialysis machine has a blood flow path for carrying a volume of blood to be treated in a dialyser and a dialysate flow path, isolated from the blood flow path, for delivering a flow of dialysate solution through the dialyser. The cartridge is received in an engine section of the machine. The engine section has first and second platens which close when the cartridge is inserted to retain the cartridge. Actuators and sensors arranged on the second platen control operation of the cartridge.

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 servicing regime for a disposable set of a medical fluid therapy machine is disclosed. In an example, a medical fluid delivery system includes a medical fluid therapy machine operating with a disposable set over multiple treatments to mix for each treatment at least one concentrate with purified water to form a medical fluid. The medical fluid delivery system also includes a sensor configured to measure an accuracy of the medical fluid mixed by the medical fluid therapy machine. The sensor is configured to produce a mixing accuracy output. The medical fluid delivery system further includes a computer programmed to analyze the mixing accuracy output provided by the sensor to determine whether the disposable set needs to be replaced.