Blood in a separation chamber is separated into a red blood cell layer, a plasma constituent, and a mononuclear cell-containing layer. A portion of the plasma constituent exits the chamber via a plasma outlet, while a first portion of the red blood cell layer exits via a red blood cell outlet. A second portion of the red blood cell layer exits the chamber via the red blood cell outlet and is collected. At least a portion of the collected red blood cell layer may then be conveyed to the chamber via the red blood cell outlet to convey at least a portion of the mononuclear cell-containing layer out of the chamber via the plasma outlet for collection. A second portion of the plasma constituent may be conveyed out of the chamber via the plasma outlet to more fully collect the mononuclear cell-containing layer without the use of collected plasma.

Described are embodiments that include methods and devices for separating components from multi-component fluids. Embodiments may involve use of separation vessels and movement of components into and out of separation vessels through ports. Embodiments may involve the separation of plasma from whole blood. Also described are embodiments that include methods and devices for positioning portions, e.g., loops, of disposables in medical devices. Embodiments may involve use of surfaces for automatically guiding loops to position them into a predetermined position.

Described are embodiments that include methods and devices for separating components from multi-component fluids. Embodiments may involve use of separation vessels and movement of components into and out of separation vessels through ports. Embodiments may involve the separation of plasma from whole blood. Also described are embodiments that include methods and devices for positioning portions, e.g., loops, of disposables in medical devices. Embodiments may involve use of surfaces for automatically guiding loops to position them into a predetermined position.

Dialysis systems are disclosed comprising new fluid flow circuits. Systems may include blood and dialysate flow paths, where the dialysate flow path includes balancing, mixing, and/or directing circuits. Dialysate preparation may be decoupled from patient dialysis. Circuits may be defined within one or more cassettes. The fluid circuit fluid flow paths may be isolated from electrical components. A gas supply in fluid communication with the dialysate flow path and/or the dialyzer able to urge dialysate through the dialyzer and urge blood back to the patient may be included for certain emergency situations. Fluid handling devices, such as pumps, valves, and mixers that can be actuated using a control fluid may be included. Control fluid may be delivered by an external pump or other device, which may be detachable and/or generally rigid, optionally with a diaphragm dividing the device into first and second compartments.

An extracorporeal blood processing system comprises a plastic molded compact manifold that supports a plurality of molded blood and dialysate fluidic pathways along with a plurality of relevant sensors, valves and pumps. A disposable dialyzer is connected to the molded manifold to complete the blood circuit of the system. The compact manifold is also disposable in one embodiment and can be detachably installed in the dialysis machine.

Methods and systems for maintaining patient fluid balance during an extracorporeal cell treatment are disclosed. The method includes minimizing the amount of saline or other fluid that is returned to the donor. Saline used during priming of the fluid circuit may be used to increase the volume of the collected cells to arrive at a treatment-ready product with a suitable hematocrit.

A blood component collection system, which is one form of a biological component collection system, is equipped with a centrifugal separation device and a biological component collection device. The biological component collection device comprises a pressed soft portion pressed by a load detecting unit. The centrifugal separation device includes a collection and returning pump, and a control unit having an internal pressure computation unit which calculates a circuit internal pressure of the biological component collection device on the basis of a detection value of the load detecting unit. The internal pressure computation unit performs a zero reset process of setting a pressure value corresponding to the detection value of the load detecting unit, so as to become zero at each instance of a predetermined timing at which the collection and returning pump is stopped.

A method for priming an extracorporeal blood circuit of an apparatus for extracorporeal treatment of blood comprises: feeding a priming fluid in the extracorporeal blood circuit and into a blood side of a membrane gas exchanger (18); generating a transitory pressurization step or a plurality of transitory pressurization steps in the priming fluid flowing in the blood circuit and in the blood side of the membrane gas exchanger (18).

A hemodialysis system is disclosed. The hemodialysis system includes a dialyzer, a saline container including saline, and a disposable set comprising a blood pumping tube fluidly connected to a first end of the dialyzer, an arterial line fluidly connected to a first end of the blood pumping tube, a venous line fluidly connected to a second end of the dialyzer, a saline line fluidly connected to the blood pumping tube and the saline container, and a dialyzer line fluidly connected to a second end of the blood pumping tube and a second end of the dialyzer. The hemodialysis system also includes a dialysis instrument comprising an arterial line clamp, a venous line clamp, and a saline valve. The saline rinses blood out of the arterial line when the venous line clamp is closed, the arterial line clamp is opened, and the saline value is opened.

Blood in a separation chamber is separated into a red blood cell layer, a plasma constituent, and a mononuclear cell-containing layer. A portion of the plasma constituent exits the chamber via a plasma outlet, while a first portion of the red blood cell layer exits via a red blood cell outlet. A second portion of the red blood cell layer exits the chamber via the red blood cell outlet and is collected. At least a portion of the collected red blood cell layer may then be conveyed to the chamber via the red blood cell outlet to convey at least a portion of the mononuclear cell-containing layer out of the chamber via the plasma outlet for collection. A second portion of the plasma constituent may be conveyed out of the chamber via the plasma outlet to more fully collect the mononuclear cell-containing layer without the use of collected plasma.