Abstract:
A machine for controlling a medical fluid includes a base (80) and an actuator (82) comprising an electroactive polymer and disposed on the base. The actuator is configured for movement between an extended position and a contracted position. A valve head (84) is disposed on the actuator and adapted to engage a flexible.membrane (59) of a cassette (23) against a valve seat (72) of the cassette when the actuator is extended to perform a valving function to control the flow of a fluid within the cassette.
Abstract:
A dialysate testing method in one embodiment includes placing electrical contacts in a dialysate flow path, measuring an electrical property of the dialysate as it flows through the flow path and past the contacts, and determining whether the dialysate has been mixed properly from the detected electrical property. A dialysate testing method in another embodiment includes flowing dialysate past a pair of electrical contacts, calculating a conductivity of the dialysate using an algorithm that takes into account a geometry of the contacts, and using the calculated conductivity to determine if the dialysate has been removed properly.
Abstract:
A dialysis fluid cassette includes a rigid portion defining at least one valve chamber, the rigid portion further defining an air separation chamber, the air separation chamber when in an operating position including a first sidewall and a second sidewall, a first fluid opening, a second fluid opening, and a separation wall extending from the first sidewall to the second sidewall, the separation wall having a free edge residing within the air separation chamber, the separation wall forcing the dialysis fluid to flow from one of the fluid openings around the free edge of the separation wall to the other of the openings.
Abstract:
A system and method for balancing flows of renal replacement fluid is disclosed. The method uses pressure controls and pressure sensing devices to more precisely meter and balance the flow of fresh dialysate and spent dialysate. The balancing system may use one or two balancing devices, such as a balance tube, a tortuous path, or a balance chamber.
Abstract:
A dialysis system instrument includes a dialysis instrument (10), a disposable pumping and valving cassette apparatus (30) operable with pumping and valving actuators of the dialysis instrument, the disposable cassette (50) including an electronic cell (100c) and electronics associated with the electronic cell, the electronics configured to determine an electrical property of a solution flowing through the electronic cell of the disposable apparatus.
Abstract:
A dialysis fluid cassette includes a rigid portion defining at least one valve chamber, the rigid portion further defining an air separation chamber, the air separation chamber when in an operating position including a first sidewall and a second sidewall, a first fluid opening, a second fluid opening, and a separation wall extending from the first sidewall to the second sidewall, the separation wall having a free edge residing within the air separation chamber, the separation wall forcing the dialysis fluid to flow from one of the fluid openings around the free edge of the separation wall to the other of the openings.
Abstract:
A dialysate testing method in one embodiment includes placing electrical contacts in a dialysate flow path, measuring an electrical property of the dialysate as it flows through the flow path and past the contacts, and determining whether the dialysate has been mixed properly from the detected electrical property. A dialysate testing method in another embodiment includes flowing dialysate past a pair of electrical contacts, calculating a conductivity of the dialysate using an algorithm that takes into account a geometry of the contacts, and using the calculated conductivity to determine if the dialysate has been removed properly.
Abstract:
A dialysis system instrument includes a dialysis instrument (10), a disposable pumping and valving cassette apparatus (30) operable with pumping and valving actuators of the dialysis instrument, the disposable cassette (50) including an electronic cell (100c) and electronics associated with the electronic cell, the electronics configured to determine an electrical property of a solution flowing through the electronic cell of the disposable apparatus.
Abstract:
A dialysis fluid heating system includes a plurality of conductive tubes; first and second end caps located at first and second ends of the tubes, respectively, the first end cap including a dialysis fluid inlet and a dialysis fluid outlet, the end caps and the tubes configured such that dialysis fluid can flow from the fluid inlet of the first end cap, through at least one first tube to the second end cap, and through at least one second tube back to the first end cap; a conductive wire wound around an outside of the conductive tubes; and electronics configured to supply power to the conductive wire, the wire forming a primary coil of a transformer, the tubes forming a secondary coil of the transformer.
Abstract:
A system and method for bal-ancing flows of renal replacement fluid is dis-closed. The method uses pressure controls and pressure sensing devices to more precisely me-ter and balance the flow of fresh dialysate and spent dialysate. The balancing system may use one or two balancing devices, such as a balance tube, a tortuous path, or a balance chamber.