Abstract:
Blood separation systems and methods utilize a membrane separation device (52) comprising a gap (60) between a microporous membrane (64) and a surface (56) facing the microporous membrane (64), one of the microporous membranes (64) and the surface (56) being rotatable relative to the other to cause separation of whole blood in the gap (60) into plasma and concentrated red blood cells. The systems and methods include an inlet pump element (20) and a drive element (46) coupled to the membrane separation device (52) and the steps of commanding the inlet pump element (20) and the drive element (46) as a function of the known beginning hematocrit value to obtain concentrated red blood cells having a high end hematocrit value that remains substantially constant despite variances in the known beginning hematocrit value.
Abstract:
Blood separation systems (200) and methods operate a pump (230) in the inlet line to convey a volume of whole blood from a donor (210) at a commanded flow rate for processing into plasma constituent (228) and concentrated red blood cells (204). The systems (200) and methods set the commanded flow rate to vary the volume of whole blood conveyed over time as a function of known hematocrit value of the selected donor (244), a targeted collection time (246) and a targeted volume of concentrated red blood cells (248). The systems and methods obtain, after processing of whole blood volume, a targeted volume of concentrated red blood cells, which is substantially constant for the population of blood donors despite variances in known hematocrit values among the donors.
Abstract:
A method and apparatus for priming an extracorporeal blood circuit, in which the patient end of an arterial line (79) is connected to a first discharge port (61), and the patient end of a venous line (87) is connected to a second discharge port (62). The two discharge ports are connected to a used dialysate line which connects a dialyser (33) to a drain. The arterial and venous lines are filled with a priming fluid, while the air contained in the arterial and venous lines is evacuated partly through the first discharge port and partly through the second discharge port. Two check valves (65, 66) prevent flow from the used dialysate line towards the two discharge ports. The invention reduces the risk of errors on the part of an operator readying the priming configuration, as well as the risk of contamination of the extracorporeal circuit during the priming phase.
Abstract:
A fluid flow control apparatus for use in separation and filtration is described which has a removable sterilisable/disposable element (27) which is engageable with a fixed portion (26). When engaged the flow of fluid around a fluid circuit is controlled to optimise separation. The removable element (27) may be combined with a filter unit (16) to form a unitary disposable cassette (90). Sensors (38, 40; 165, 167) can be incorporated in the apparatus for measuring fluid parameters such as pressure, viscosity and pH. Pressure sensors (165, 167; 226, 228) disposed at the filter inlet and outlet, are used to control the transmembrane pressure (TMP) to optimise filtration or separation and in one application this is used in controlling donor plasma separation.