Abstract: A system is provided for weighing and monitoring flow from multiple fluid sources into a flow system wherein incoming fluid is received in a weighing bag attached to a control system for monitoring the amount of fluid passed through the weighing bag and for preventing admission of air into the flow system. An alarm attached to the weighing bag warns when fluid in the weighing bag is approaching empty, so that the fluid in the weighing bag can be replenished from the fluid source before the weighing bag runs dry. If fluid in the weighing bag is not replenished, the system automatically shuts down.The fluid pump can be absolutely calibrated using the controlled admission of known amounts of fluid into the weighing bag so that the amount of fluid introduced into the flow system through the weighing bag can be calculated automatically.

Abstract: The system includes a plasmapheresis instrument and a harness set applied to the instrument. The harness set has a single venepuncture needle and is configured, when applied to the instrument, to pump blood from a donor through a separator for collection of its constituent parts in a reservoir and a collection container, respectively. During an infusion cycle, which alternates with the collection cycle, the blood constituent from the reservoir and a replacement fluid are mixed externally of the reservoir and pumped to the donor.

Abstract: An adaptive filter concentrate flow control system and method includes a filter system, a pumping system driving feed fluid, concentrate and filtrate flowing through the filter system and a flow control system controlling the pumping system to maintain optimum filtrate flow rates along a control curve in a transmembrane pressure--feed fluid rate--filtrate flow rate three dimensional space. Actual sensed operating point data is used to locate the control curve so as to assure an optimized filtrate flow rate at which reversible blocking of the membrane has begun to occur without irreversible plugging. The system is advantageously employed to control and maximize the flow of plasma in a plasmapheresis system.