A peritoneal dialysis system includes a control unit configured to cause (i) a fluid inlet valve and a fluid outlet valve to occlude a fluid inlet line and a fluid outlet line, respectively, while a linear actuator moves a piston to create a positive pressure within a pump housing, the positive pressure measured by a pressure sensor, and (ii) the fluid inlet valve to occlude the fluid inlet line and the fluid outlet valve to open the fluid outlet line, while the linear actuator moves the piston so as to maintain the positive pressure within the pump housing while fluid is pumped out of the fluid pump chamber via the opened fluid outlet line.

A dialysis machine (e.g., a peritoneal dialysis (PD) machine) can include a pressure sensor mounted at a proximal end of a patient line made of a distensible material that provides PD solution to a patient through a catheter. During treatment, an occlusion can occur at different locations in the patient line and/or the catheter. When an incremental volume of additional solution is provided to the patient line while the occlusion is present, a change in pressure results. The change in pressure depends on dimensions and a distensibility of a non-occluded portion of the patient line. If the change in pressure, the incremental volume, properties related to the distensibility of the patient line, and some of the dimensions of the patient line are known, a location of the occlusion can be inferred. An occlusion type can be inferred based on the location of the occlusion.

A fluid pumping system may comprise a pump and a fluid line state detector having, a receptacle, at sensor, and an illuminator. The system may further comprise a fluid transfer set including an output line for mating into the receptacle. The system may further comprise a controller in data communication with the fluid line state detector configured to power the illuminator and monitor an output signal of the sensor when the outlet line is in the receptacle to determine a dry tube light intensity value. The controller may be further configured to govern operation of the pump to prime the output line with fluid. The controller may be further configured to power the illuminator, monitor the output signal, and halt operation of the pump when the output signal indicates the light intensity value has dropped below a primed line threshold which is dependent upon the dry tube intensity value.

A fluid handling cassette, such as that useable with an automated peritoneal dialysis (APD) cycler device or other infusion apparatus, may include a generally planar body having at least one pump chamber formed as a depression in a first side of the body and a plurality of flowpaths for a fluid that includes a channel. A patient line port may be arranged for connection to a patient line and be in fluid communication with the at least one pump chamber via at least a first one of said flowpaths, and an optional membrane may be attached to the first side of the body over the at least one pump chamber. In one embodiment, the membrane may have a pump chamber portion with an unstressed shape that generally conforms to the depression of the at least one pump chamber in the body and is arranged to be movable for movement of the fluid in a useable space of the at least one pump chamber. One or more spacers may be provided in the at least one pump chamber to prevent the membrane from contacting an inner wall of the at least one pump chamber. The patient line, a drain line, and/or a heater bag line may be positioned to be separately occludable in relation to one or more solution lines that are connectable to the cassette.

A hemodialysis machine comprising a dialysate flow path for delivering a flow of dialysate solution through a dialyser, the flow path including a flow balancer for achieving a balance in the dialysate solution flow volume observed between an inlet and an outlet of the dialyser over the course of a treatment, the flow balancer comprising a first flow balance pump having an inlet valve and an outlet valve and a second flow balance pump having an inlet valve and an outlet valve, wherein the flow path further includes a flow restrictor means downstream of the flow balance pumps to reduce the pressure difference across the valves in the dialysate flow path.

A dialysis method to enable a patient to undergo both peritoneal dialysis and extracorporeal blood treatments is disclosed. The method includes determining, via a base unit controller, whether a peritoneal dialysis treatment or an extracorporeal blood treatment is to be performed. If the peritoneal dialysis treatment is to be performed, the method includes operating first software instructions that cause a base unit to use a first fluid stored in a fluid container. If the extracorporeal blood treatment is to be performed, the method includes operating second software instructions that cause the base unit to use a second, different fluid from an online source and selectively move the second, different fluid to a blood treatment unit for use in the extracorporeal blood treatment. The blood treatment unit is operable with the base unit to perform the extracorporeal blood treatment on a patient.

A capacitive priming sensor for a medical fluid delivery system is disclosed. In an example embodiment, a priming sensor includes a housing including a recessed section configured to accept a portion of a tube. The recessed section of the housing includes a first side including a first conductive plate and a member including a second conductive plate. The member is moveably connected to a second side of the recessed section for detecting insertion of the portion of the tube into the housing of the priming sensor. The recessed section also includes a third side opposing the first side. The third side includes a third conductive plate disposed across from a top portion of the first conductive plate, and a fourth conductive plate disposed across from a bottom portion of the first conductive plate. The priming sensor also includes capacitive sensors or detectors for measuring capacitances between the conductive plates.

A renal therapy machine includes a blood filter including a plurality of porous fibers; a blood circuit in communication with the blood filter; and a dialysate circuit in communication with the blood filter and operable with at least one pump, wherein the renal therapy machine is configured to perform a priming sequence in which a physiologically compatible solution, other than dialysate, primes the blood circuit and is flowed within the fibers and through pores in the fibers of the blood filter, and the pump of the dialysate circuit vents air from the blood filter into the dialysate circuit.

Dialysis systems comprising actuators that cooperate to perform dialysis functions and sensors that cooperate to monitor dialysis functions are disclosed. According to one aspect, such a hemodialysis system comprises a user interface model layer, a therapy layer, below the user interface model layer, and a machine layer below the therapy layer. The user interface model layer is configured to manage the state of a graphical user interface and receive inputs from a graphical user interface. The therapy layer is configured to run state machines that generate therapy commands based at least in part on the inputs from the graphical user interface. The machine layer is configured to provide commands for the actuators based on the therapy commands.

A method is provided for detecting leaks in a disposable medical fluid cassette that includes a base and a flexible membrane attached to the base in such a way that the base and the flexible membrane cooperate to at least partially form a fluid passageway. The method includes applying a first force to the flexible membrane, measuring a first physical property of a system that includes the medical fluid cassette a medical fluid pumping machine, removing the first force from the flexible membrane, applying a second force to the flexible membrane, measuring a second physical property of the system, and determining whether the medical fluid cassette leaks based on a comparison of the first physical property and the second physical property.