An assembly includes first and second assemblies, the first assembly including a frame defining a recess, a first plate disposed within the recess, and a bellows disposed between the first plate and an inner surface of the frame. The second assembly includes a second plate configured to be opposite the first plate when the first assembly is in a closed position relative to the second assembly. The first assembly is configured to move relative to the second assembly between an open position and the closed position, and a latch assembly configured to hold the first assembly to the second assembly in the closed position. The bellows is configured to inflate to apply a force to the first plate towards the second plate when the first assembly is in the closed position.

A method of sanitizing liquid for use in a medical device, the method comprising the steps of providing a medical device defining a water circuit with a volume of liquid, sensing the temperature of the volume of liquid with a sensor, heating the volume of liquid from an initial temperature to exceed a threshold temperature, maintaining the volume of liquid above the threshold temperature, determining a time-temperature value for the volume of liquid periodically once the threshold temperature has been exceeded, calculating a cumulative time-temperature value and providing an output signal once the cumulative time-temperature value has reached a level indicative of a sanitizing dose. A medical device and a liquid sanitizer are also disclosed.

Systems, methods, and devices directed to a peritoneal dialysis cassette and an interface between the cassette and a peritoneal dialysis system is provided. The peritoneal dialysis cassette can include one or more fluid flow paths connecting a plurality of inlet/outlet ports, one or more rotary valves for selectively directing fluid through the peritoneal dialysis cassette, and a pump.

In one aspect, a valve actuation system includes a drive unit including an actuator configured to engage and move multiple valves disposed within a fluid cassette to selectively open and close each valve of the multiple valves and a positioning frame disposed adjacent the fluid cassette and along which the drive unit can be moved in three dimensions to align the actuator with a selected valve of the multiple valves.

A pneumatic system for a medical fluid machine operating a medical fluid cassette, the pneumatic system including an interface for supplying positive pneumatic pressure and negative pneumatic pressure to the medical fluid cassette; a source of positive pneumatic pressure; a source of negative pneumatic pressure; and a pneumatic pump including a first head and a second head, wherein the first head is dedicated to supplying positive pneumatic pressure to the positive pneumatic pressure source and the second head is dedicated to supplying negative pneumatic pressure to the negative pneumatic pressure source.

In one aspect, a valve actuation system includes a drive unit including an actuator configured to engage and move multiple valves disposed within a fluid cassette to selectively open and close each valve of the multiple valves and a positioning frame disposed adjacent the fluid cassette and along which the drive unit can be moved in three dimensions to align the actuator with a selected valve of the multiple valves.

A peritoneal dialysis system for detecting peritonitis is disclosed herein. In one example, an impedance measurement system includes an impedance monitor configured to sense an impedance of peritoneal dialysis (“PD”) fluid residing within a fluid line. The impedance monitor includes a first conductive lead disposed within a first port along the fluid line and a second conductive lead disposed within a second port along the fluid line. The impedance measurement system also includes a control unit electrically coupled to the impedance monitor. The control unit uses the sensed impedance from the impedance monitor to detect white blood cells to form a patient peritonitis determination. The control unit may communicate the peritonitis determination to alert a clinician.

An inductive inline dialysis fluid heater is disclosed. In an example, a dialysis fluid heater includes a cylindrical tube including an inner diameter that is between 4.00 millimeters (“mm”) and 12.7 mm. The dialysis fluid heater also includes a susceptor located within the cylindrical tube and an inductive coil extending around the cylindrical tube in a non-contacting arrangement. The dialysis fluid heater further includes power electronics in electrical communication with the inductive coil and configured to supply an electrical current to the inductive coil, causing the susceptor to heat.

A fluid purification unit is disclosed. In an example, a fluid purification unit includes a heater configured to boil a fluid. The heater includes first and second electrodes positioned and arranged to contact the fluid. The first and second electrodes are configured to receive electrical power, heat resistively due to the electrical power, and transfer the heat to the fluid to boil the fluid to form water vapor. The fluid purification unit also includes a condenser including (i) a thermally conductive flowpath configured to conductively cool the water vapor, and (ii) a cooling source configured to direct a cooling medium past the thermally conductive flowpath to convectively cool the water vapor. The conductive and convective cooling combines to condense the water vapor into purified water.

This disclosure relates to medical fluid cassettes and related systems and methods. In certain aspects, a medical fluid cassette includes a base having a first region and a second region, a first membrane overlying the first region of the base, and a second membrane overlying the second region of the base. The second membrane is configured to rebound away from the base when a force used to press the second membrane toward the base is released.