A sensing and storage system for fluid balance during dialysis is provided. The sensing and storage system has flow sensors on either side of a dialyzer in a controlled volume dialysate flow path. The sensors are positioned so that no fluid can be added to or removed from the dialysate flow path between the sensors except for that which is added or removed by action of a control pump. The sensing and storage system can have a fluid removal line for the removal of fluid from the dialysate flow loop.

A system for calculating cardiac output (CO) of a patient undergoing veno-arterial extracorporeal oxygenation includes measuring first oxygenated blood flow rate by a pump in the extracorporeal blood oxygenation circuit as introduced into an arterial portion of the patient circulation system and a corresponding arterial oxygen saturation, then changing the pump flow rate, such as decreasing, to produce a corresponding change in arterial oxygen saturation (wherein such change is outside of normal operating variances, operating errors or drift), which change in the arterial oxygen saturation is measured. From the first flow rate and the second flow rate along with the corresponding measured arterial oxygen saturation, the CO of the patient can be calculated, without reliance upon a measure of venous oxygen saturation. Alternatively, the CO of the patient can be calculated, without reliance upon a change in flow rate by changing a gas exchange with the blood in the extracorporeal blood oxygenation circuit to impart corresponding changes in a blood parameter in the arterial portion of the patient circulation system and the blood delivered from the extracorporeal blood oxygenation circuit.

The disclosed subject matter relates to extracorporeal blood processing or other processing of fluids. Volumetric fluid balance, a required element of many such processes, may be achieved with multiple pumps or other proportioning or balancing devices which are to some extent independent of each other. This need may arise in treatments that involve multiple fluids. Safe and secure mechanisms to ensure fluid balance in such systems are described.

A method of preserving a sorbent device of a dialysis system, the method comprising—after administering a first dialysis treatment at the dialysis system and before administering a second dialysis treatment at the dialysis system—circulating a fluid through the sorbent device to prevent matter within the sorbent device from solidifying and circulating the fluid through a filter coupled to an outlet of the sorbent device to remove contaminants from the fluid.

A portable hemodialysis system is provided including a dialyzer, a closed loop blood flow path which transports blood from a patient through the dialyzer and back to the patient, and a closed loop dialysate flow path which transports dialysate through the dialyzer. Preferably, the hemodialysis system includes a sorbent filter in the dialysate flow path. Furthermore, the hemodialysis machine includes a blood pump, and a pair of dialysate pumps. A processor controls the flow of blood through the blood flow path, and the processor controls the flow of dialysate through the dialysate flow path. In addition, the processor stores a patient treatment plan wherein the flow rate of the dialysate through the dialysate flow path reduces throughout the patient's treatment to maximize the amount of urea removed by the sorbent filter.

A portable hemodialysis system is provided including a dialyzer, a closed loop blood flow path which transports blood from a patient to the dialyzer and back to the patient, and a closed loop dialysate flow path which transports dialysate through the dialyzer. In addition, the hemodialysis system includes two reservoirs which can be alternately placed in the dialysis flow path using various controllable fluid valves. The weight, and therefore the level of dialysate, of each reservoir is measured by a preferred level sensor having a lever arm, a load cell, and a tilt sensor. The load cell and tilt sensor are electrically connected to a processor for sending force and tilt measurements to the processor. The processor may analyze the tilt measurements to correct for any inaccurate measurements of the load cell caused by the tilt.

The disclosed subject matter relates to extracorporeal blood processing or other processing of fluids. Volumetric fluid balance, a required element of many such processes, may be achieved with multiple pumps or other proportioning or balancing devices which are to some extent independent of each other. This need may arise in treatments that involve multiple fluids. Safe and secure mechanisms to ensure fluid balance in such systems are described.

A system for calculating cardiac output (CO) of a patient undergoing veno-arterial extracorporeal oxygenation includes measuring first oxygenated blood flow rate by a pump in the extracorporeal blood oxygenation circuit as introduced into an arterial portion of the patient circulation system and a corresponding arterial oxygen saturation, then changing the pump flow rate, such as decreasing, to produce a corresponding change in arterial oxygen saturation (wherein such change is outside of normal operating variances, operating errors or drift), which change in the arterial oxygen saturation is measured. From the first flow rate and the second flow rate along with the corresponding measured arterial oxygen saturation, the CO of the patient can be calculated, without reliance upon a measure of venous oxygen saturation. Alternatively, the CO of the patient can be calculated, without reliance upon a change in flow rate by changing a gas exchange with the blood in the extracorporeal blood oxygenation circuit to impart corresponding changes in a blood parameter in the arterial portion of the patient circulation system and the blood delivered from the extracorporeal blood oxygenation circuit.

The disclosure relates to systems and methods for increasing the functional capabilities of a sorbent-based dialysis system. The systems and methods allow for the mode of operation of the dialysis system to be switched between single pass mode and a sorbent based multi-pass mode by controlling an amount of water added to the dialysate between 0% to 100% of the dialysate flow rate.

The disclosed subject matter relates to extracorporeal blood processing or other processing of fluids. Volumetric fluid balance, a required element of many such processes, may be achieved with multiple pumps or other proportioning or balancing devices which are to some extent independent of each other. This need may arise in treatments that involve multiple fluids. Safe and secure mechanisms to ensure fluid balance in such systems are described.