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.

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 an apparatus being modeled using a combination of adiabatic, isothermal and polytropic processes. Real time or instantaneous fluid flow measurements in a pump chamber of the 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.

A dialysis system may include a dialysis machine (e.g., a peritoneal dialysis machine) having a fluid system for delivering fluid (e.g., dialysate) to a patient. The dialysis machine may include at least one processor and a memory coupled to the at least one processor, the memory comprising instructions that, when executed by the processor, may cause the at least one processor to determine volume information for a fluid system of a dialysis machine, wherein the volume information may comprise a patient line volume and an accuracy adjustment volume, and to determine a priming volume to prime the fluid system with a fluid based on the volume information. Other embodiments are described.

A peritoneal dialysis (“PD”) system includes a housing; a dialysis fluid pump housed by the housing and including a reusable pump body that accepts PD fluid for pumping; a dialysis fluid inline heater housed by the housing and including a reusable heater body that accepts PD fluid for heating; at least one reusable PD fluid line extending from the housing; at least one disinfection connector supported by the housing and configured to accept one of the at least one reusable PD fluid line; and a control unit configured to run a disinfection sequence after a PD treatment, wherein each of the at least one reusable PD fluid line is connected to one of the at least one disinfection connectors, and wherein at least one of the dialysis fluid pump or the dialysis fluid inline heater is actuated by the control unit during the disinfection sequence.

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 solution 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.

A medical treatment system, such as a peritoneal dialysis system, may include a control and other features to enhance patient comfort and ease of use. For example, a cycler device may include a heater bag receiving section and a lid mounted to cover and uncover the heater bag receiving section, potentially enabling faster heating of a dialysate. A user interface may be moveable to be received into the receiving section and covered by the lid, if desired. The system may detect anomalous conditions, such as tilting of a housing of the system, and automatically recover without terminating a treatment. The system may include noise reduction features, such as porting pneumatic outputs to a common chamber, and others. The system may also automatically detect any one of several different solution lines connected to the system, and control operation accordingly, e.g., to mix solutions provided by two or more lines and form a needed dialysate solution. A cassette control surface may be arranged to have one or more ports that can detect a presence of a liquid, e.g., to identify if a cassette is leaking or has otherwise been compromised.

A method that includes pumping medical fluid out of or drawing medical fluid into a chamber of a medical fluid cassette, calculating a theoretical volume of fluid pumped out of or drawn into the chamber, and multiplying the theoretical volume of fluid pumped out of or drawn into the chamber by a correction factor to determine a corrected volume of fluid pumped out of or drawn into the chamber.

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.

Components for a medical infusion fluid handling system, such as an APD system, in which one or more lines (such as solution lines), spikes or other connection ports may be automatically capped and/or de-capped. This feature may provide advantages, such as a reduced likelihood of contamination since no human interaction is required to de-cap and connect the one or more lines, the spikes or the other connection ports. For example, a fluid handling cassette may include one or more caps that cover a corresponding spike and include a raised and/or recessed feature to assist in removal of the one or more caps from the cassette. A solution line cap may include a hole and a recess, a groove or other feature to engage with a spike cap and enable removal of the spike cap.

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 being modeled using a combination of adiabatic, isothermal and polytropic processes. Real time or instantaneous fluid flow measurements in a pump chamber of the 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 element. Improvements are also disclosed in an application of negative pressure during a drain phase in peritoneal dialysis therapy, and to control an amount of intraperitoneal fluid accumulation during the therapy. Improvements in efficiency are also disclosed in movement of fluid into and out of a two-pump cassette and a heater bag of the peritoneal dialysis cycler, and in synchronization of operation of two or more pumps in the peritoneal dialysis cycler or other fluid handling devices using a multi-pump arrangement.