An extracellular fluid volume calculator may include: a first acquirement unit configured to acquire a pre-hemodialysis plasma uric acid concentration, a post-hemodialysis plasma uric acid concentration, a removal amount of uric acid by hemodialysis, and a removal volume of water during hemodialysis; and a first processor configured to calculate an extracellular fluid volume based on a difference between a pre-hemodialysis amount of uric acid and a post-hemodialysis amount of uric acid, the difference being determined based on the pre-hemodialysis plasma uric acid concentration, the post-hemodialysis plasma uric acid concentration, the removal amount of uric acid, and the removal volume of water acquired by the first acquirement unit.

A control device for a blood treatment machine performs a connection test (50) by causing the blood treatment machine to switch (51, 53) between a first and a second operating state by reversing a blood pump so as to change a flow direction of blood through both a dialyzer and access devices connected to a patient. Based on an output signal of at least one sensor in the blood treatment machine (52, 54), the control device computes (55) an efficiency change parameter that represents a change in in-vivo clearance of the blood treatment machine during the switch of the blood treatment machine between the first and second operating states. The control device evaluates (56) the efficiency change parameter to jointly detect connection errors at the dialyzer, resulting in co-current flow of treatment fluid and blood through the dialyzer, and at the access devices, resulting in access recirculation of blood.

Systems, devices, and methods are provided for removing carbon dioxide from a target fluid, such as, for example, blood, to treat hypercarbic respiratory failure or another condition. A device is provided including first and second membrane components for removing dissolved gaseous carbon dioxide and bicarbonate from the fluid, which can be done simultaneously. The device can be in the form of a cartridge configured for use in a dialysis system. A method of treatment is also provided, involving drawing blood from a patient and bringing the patient's blood in contact with a first membrane component having a sweep gas passing therethrough, and a second membrane component having a dialysate passing therethrough. The dialysate's composition can be selected such that charge neutrality is maintained.

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.

A cassette module (19, 29, 319, 419, 59, 69) for a differential flowmeter is disclosed, wherein the cassette module (19, 29, 319, 419, 59, 69) forms a first fluid-carrying channel (16, 216, 316, 611, 615) and the second fluid-carrying channel (17, 217, 317, 610, 616) during operation of the differential flowmeter. The cassette module is specific in the regard that a geometric deformation of the channels due to a temperature difference between the channels (16, 216, 316, 611, 615, 17, 217, 317, 610, 616) is minimized or prevented. In addition a differential flowmeter containing the cassette module (19, 29, 319, 419, 59, 69) disclosed here is also described.

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.

Hemodialysis is used to remove fluid from a patient suffering from end-stage renal kidney disease. An optimization-based approach including a design of an individualized ultrafiltration rate profile may be used to prevent hematocrit levels from exceeding a threshold, thereby preventing adverse effects in the patient. The individualized ultrafiltration rate profile may be based on previously obtained clinical data for the patient, a volume of fluid to be removed from the patient, a specified period of time for removal of the fluid, or a patient-specific fluid volume model. The ultrafiltration rate profile may be time-variant over the specified period of time.

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.

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 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.