Improvements in fluid volume measurement systems are disclosed for a pneumatically actuated diaphragm pump in general, and a peritoneal dialysis cycler using a pump cassette in particular. Pump fluid volume measurements are based on pressure measurements in a pump control chamber and a reference chamber in a two-chamber model, with different sections of the apparatus being modeled using a combination of adiabatic, isothermal and polytropic processes. Real time or instantaneous fluid flow measurements in a pump chamber of a diaphragm pump are also disclosed, in this case using a one-chamber ideal gas model and using a high speed processor to obtain and process pump control chamber pressures during fluid flow into or out of the pump chamber. Improved heater control circuitry is also disclosed, to provide added or redundant safety measures, or to reduce current leakage from a heater element during pulse width modulation control of the heater. Improvements are also disclosed in the application of negative pressure during a drain phase in peritoneal dialysis therapy, and to control the amount of intraperitoneal fluid accumulation during a therapy. Improvements in efficiency are also disclosed in the movement of fluid into and out of a two-pump cassette and heater bag of a peritoneal dialysis cycler, and in the synchronization of the operation of two or more pumps in a peritoneal dialysis cycler or other fluid handling devices using a multi-pump arrangement.

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 hybrid hemodialysis (HD)/peritoneal dialysis (PD) system includes: a reservoir; a weigh scale operably coupled with the reservoir; and at least one controller programmed to run (i) an HD treatment in which blood is pumped to a blood compartment of a dialyzer, fresh HD dialysis fluid is pumped to a dialysis fluid compartment of the dialyzer, and used HD dialysis fluid is pumped from the dialysis fluid compartment of the dialyzer to the reservoir, and at a different time (ii) a PD treatment in which fresh PD dialysis fluid is pumped to a patient and used PD dialysis fluid is pumped from the patient to the reservoir.

Devices, systems, and methods can be used to deliver temperature-controlled medical fluids to patients. For example, this disclosure provides devices, systems, and methods for controlling the temperature of dialysate delivered to a patient during a peritoneal dialysis treatment.

A dialysis system includes a fluid line fluidly communicating with a fluid source, a peritoneal dialysis configured to be placed in fluid communication with the fluid line, the peritoneal dialysis including a first user interface and a first control unit, the first user interface configured to receive first user inputs related to a peritoneal dialysis treatment, the first control configured to operate the peritoneal dialysis in accordance with the first user inputs to perform the peritoneal dialysis treatment, and a blood treatment configured to be placed in fluid communication with the fluid line, the blood treatment including a second user interface and a second control unit, the second user interface configured to receive second user inputs related to a blood treatment, the second control configured to operate the blood treatment in accordance with the second user inputs to perform the blood treatment.

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 hemodialysis system configured to purge air from a blood circuit comprising: a dialyzer; a dialysis fluid circuit operable with the dialyzer via dialysis fluid inlet and outlet lines; the blood circuit operable with the dialyzer and including an arterial line, a venous line, a blood pump operable with the arterial line upstream of the dialyzer, and a physiologically acceptable fluid source in fluid communication with the arterial line upstream of the blood pump; and an air purging scheme wherein, with the dialysis fluid inlet and outlet lines connected to the dialyzer, air is purged using dialysis fluid or other physiologically acceptable fluid pumped by at least one of the fresh or used dialysis fluid pumps from the dialysis fluid circuit, through the dialyzer, into the blood circuit, in combination with dialysis fluid or other physiologically acceptable fluid from the source introduced directly into the blood circuit.

A peritoneal dialysis (PD) fluid line set includes a fluid line configured to carry spent dialysate to a drain receptacle and a chemical testing device disposed along the fluid line. The chemical testing device is configured to detect a presence of a substance in the spent dialysate as the spent dialysate flows past the chemical testing device, and the chemical testing device is configured to provide a visual indicator of the presence of the substance in the spent dialysate.

A dialysis system including a disposable fluid pumping cassette including at least one flexible membrane attached to a housing and at least one port extending from the housing, the at least one port including a spike; at least one dialysis fluid supply in fluid communication with at least one tubing and tubing connector; an autoconnection device including a shuttle for moving the at least one tubing and tubing connector towards the spike of the at least one port, the autoconnection device including at least one lead screw in mechanical communication with the shuttle, a motor and power transmission equipment to transmit power from the motor to the at least one lead screw; and a controller programmed to operate the motor to move the at least one tubing and tubing connector towards the spike of the at least one port of the disposable fluid pumping cassette.

A hemodialysis system is disclosed. The hemodialysis system includes a dialyzer, a saline container including saline, and a disposable set comprising a blood pumping tube fluidly connected to a first end of the dialyzer, an arterial line fluidly connected to a first end of the blood pumping tube, a venous line fluidly connected to a second end of the dialyzer, a saline line fluidly connected to the blood pumping tube and the saline container, and a dialyzer line fluidly connected to a second end of the blood pumping tube and a second end of the dialyzer. The hemodialysis system also includes a dialysis instrument comprising an arterial line clamp, a venous line clamp, and a saline valve. The saline rinses blood out of the arterial line when the venous line clamp is closed, the arterial line clamp is opened, and the saline value is opened.