This disclosure relates to a method for determining a fluid balance between a first volume flow in a first section of a fluid circuit and a second volume flow of a second section of the fluid circuit. The method may also include adjusting, assuming or detecting a first temperature in the first section of the fluid circuit and a second temperature in the second section of the fluid circuit, or detecting a temperature difference between the first and the second sections. The method may also include detecting a second volume flow in a second section of the fluid circuit and forming a balance from at least the first volume flow and a corrected value of the second volume flow. The corrected value is determined from the detected second volume flow and the second temperature and/or the temperature difference.

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 device and method are used for monitoring an extracorporeal blood treatment device, such as a dialysis machine, which includes an extracorporeal blood circuit having an arterial blood line with an arterial patient port and/or at least one venous blood line with a venous patient port, and a dialysis fluid system which has a dialysis fluid supply line and a dialysis fluid drain line. The monitoring device selects and senses a measured value during operation of the extracorporeal blood treatment device which is suitable for monitoring the blood treatment device to compare a time-related actual course of the measured value with a target course of the measured value stored in a memory, and to determine that there is a defect if, at least in sections, the actual course of the measured value deviates from the target course by more than a defined tolerance.

A dialysis system includes a dialysis instrument including a blood pump, a dialysate inlet pump, a dialysate outlet pump, and at least one fluid velocity sensor, each sensor including an emitter and a receiver, a dialyzer arranged (i) to receive blood pumped by the blood pump, (ii) to receive fresh dialysate pumped by the dialysate inlet pump and (iii) such that used dialysate is pumped from the dialyzer by the dialysate outlet pump, and a disposable cassette including a to-dialyzer dialysate pathway carrying dialysate pumped by the dialysate inlet pump and a from-dialyzer dialysate pathway carrying used dialysate pumped by the dialysate outlet pump, wherein at least one of the to-dialyzer dialysate pathway or the from-dialyzer dialysate pathway includes at least one sensing area so positioned and arranged such that when the disposable cassette is mounted to the instrument, the sensing area is coupled operably with both the emitter and the receiver of the at least one fluid velocity sensor.

A blood circuit and a dialysate circuit bidirectionally circulate a fluid through a blood purification membrane of a blood purifier, and include a first flow route that causes a dialysate to flow from the dialysate circuit into the blood circuit through a connection flow route connecting the dialysate circuit to the blood circuit while bypassing the blood purifier, and a second flow route that causes the dialysate to flow from the dialysate circuit into the blood circuit through the blood purification membrane. The controller performs control such that blood in the blood circuit is returned to the body by feeding the dialysate to one of these flow routes, determine if a flow amount of the dialysate reaches a predetermined flow amount, and control such that the blood in the blood circuit is returned to the body by feeding the dialysate to the other one of these flow routes.

A system for controlling a fluid procedure comprising a reusable separation apparatus controlled by a microprocessing controller. A sterile circuit is configured to associate with the reusable separation apparatus and provide a first fluid flow path in association with a pressure sensor in communication with the controller and a first pump configured to transmit pulsatile pressure signals to the pressure sensor during operation in association with the first fluid flow path. The reusable apparatus and the controller are configured to receive from the pressure sensor pressure signals comprising the pulsatile pressure signals, perform a frequency analysis of the pressure signals received by the pressure sensor over a time duration, derive a first rotation rate of the first pump or a first fluid flow rate at the first pump from the frequency analysis, and provide a response action based on the first rotation rate or the first fluid flow rate.

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 dialysis system includes a sorbent device positioned along a fluid circuit for regenerating dialysate during a dialysis treatment carried out at the dialysis system, a filter coupled to an outlet of the sorbent device such the any fluid flowing through the sorbent device must first flow through the filter before reentering the fluid circuit, and a pump positioned downstream of the filter along the fluid circuit. The pump is operable between first and second dialysis treatments carried out at the dialysis system to circulate a fluid through the sorbent device to prevent matter within the sorbent device from solidifying and circulate the fluid through the filter to remove contaminants from the fluid.

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.

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.