A blood based solute monitoring system for measuring at least one blood solute species that has a first recirculation flow path in fluid communication with a dialyzer. The first recirculation flow path is configured to allow a fluid to recirculate through a dialyzer such that the concentration of at least one solute species in the fluid becomes equilibrated to the solute species concentration of the blood in a blood compartment of the dialyzer. The blood solute monitoring system has at least one sensor to measure a fluid characteristic.

Systems and methods for controlling fluid movement and volumes of fluid between a subject and a controlled compliant flow path. The controlled compliant flow path has a means for selectively metering in and metering out fluid from the controlled compliant flow path. An extracorporeal flow path is in fluid communication with the controlled compliant flow path across a semi-permeable membrane where the extracorporeal flow path has a first terminal end and a second terminal end.

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 blood based solute monitoring system for measuring at least one blood solute species that has a first recirculation flow path in fluid communication with a dialyzer. The first recirculation flow path is configured to allow a fluid to recirculate through a dialyzer such that the concentration of at least one solute species in the fluid becomes equilibrated to the solute species concentration of the blood in a blood compartment of the dialyzer. The blood solute monitoring system has at least one sensor to measure a fluid characteristic.

Systems and methods for controlling fluid movement and volumes of fluid between a subject and a controlled compliant flow path. The controlled compliant flow path has a means for selectively metering in and metering out fluid from the controlled compliant flow path. An extracorporeal flow path is in fluid communication with the controlled compliant flow path across a semi-permeable membrane where the extracorporeal flow path has a first terminal end and a second terminal end.

A cassette is provided for installation in a dialysis monitor to pump a treatment solution through a dialyzer. The cassette is a unitary component with a hydraulic manifold (53) and a pneumatic manifold (54) integrated into a body (52). The body (52) has connectors for connecting the hydraulic manifold (53) to the dialyzer and the pneumatic manifold (54) to a pneumatic pressure source. A set of solution pumps is integrated in the cassette, and each solution pump includes a pump cavity inside the body. The solution pumps are operable to displace the treatment solution through the hydraulic manifold (53) to and/or from the dialyzer by action of a reciprocating gas-liquid interface in the pump cavity (30) of the respective solution pump. The gas-liquid interface is formed directly between a gaseous substance and the treatment solution. A valve arrangement (58) is attached to the body (52) and operable to control admission of the gaseous substance and the treatment solution to the pump cavity (30) so as to reciprocate the gas-liquid interface and thereby pump the treatment solution through the hydraulic manifold (53). The cassette is configured to pump the treatment solution without moving parts inside the body (52).

A dialysate-extracting apparatus is provided in which scattering of dialysate that may occur when an opening-and-closing device is detached from a collecting port can be prevented and the cleanliness of the collecting port can be assuredly maintained. The dialysate-extracting apparatus includes a dialysate-extracting device connected to a dialysate flow route and having a collecting port from which dialysate flowing in the dialysate flow route is collectable, and an opening-and-closing device detachable from and attachable to the dialysate-extracting device in such a manner as to open and close the collecting port and including a seal portion that seals the collecting port in a closed state. When the opening-and-closing device is detached from the dialysate-extracting device, a part of the opening-and-closing device that is on an inner side with respect to the seal portion is bendable and displaceable toward the collecting port.

The present invention relates to a device and method for conveying fluids into the treatment unit of a medical treatment apparatus. The device and method according to the present invention are based on the fact that the fluid with which the treatment unit is supplied, circulates in a fluid circuit including the treatment unit. To balance fresh and used fluid fed to the treatment unit or conveyed from the treatment unit, a balancing unit with a balancing chamber is used, which can be incorporated into the fluid circuit including the treatment unit. It is thus possible to supply the fluid circuit continuously with fresh fluid or to carry away used fluid continuously from the fluid circuit. The supply and discharge of fresh and used fluid can take place at a different flow rate from the flow rate at which the fluid circulates in the fluid circuit via the treatment unit.

A blood treatment machine, module device and recirculation determination method feature a dialyser. A sensor is connected downstream of the dialyser and connected to a control unit that determines recirculation without blood-side bolus administration. The control unit: acquires the signal of a variable of consumed dialysis liquid measured by the sensor; switches the machine from a base mode into an interim mode, in which a dialysis liquid amount is confined in the dialyser on the dialysis liquid membrane side while blood flows in the blood circuit; changes into the base mode to supply the previously confined dialysis liquid amount as a first or second dialysis liquid bolus to the sensor to measure a signal change relative to a base signal as a corresponding first or second bolus signal; and deduces a recirculation from a deviation of the second bolus signal compared to the first bolus signal.

A dialysis fluid connection method is disclosed herein. In an example, the method includes providing a double lumen tube including a first tube lumen and a second tube lumen. The method also includes providing a connector device having a first end connected to the double lumen tube. The connector device includes a first device lumen positioned and arranged to fluidly communicate with the first tube lumen and a second device lumen positioned and arranged to fluidly communicate with the second tube lumen. The method further includes enabling a filter unit to be connected to the connector device such that a first medium flowing through the first tube lumen and the first device lumen to the filter unit is different than a second medium flowing from the filter unit, through the second tube lumen and the second device lumen.