Apheresis apparatus for separating an intermediate density component from whole blood

摘要

An apheresis apparatus for increasing the purity and yield of platelets separated from donated whole blood by centrifugation incorporates a centrifuge for separating whole blood into lower, intermediate, and higher density components. The centrifuge has inlet and outlet ports in selective fluid communication with a container for receiving lower density blood component from the outlet port. A pump is coupled to the container and the inlet port for recirculating lower density blood component from the first container through the inlet port into the centrifuge at a first, substantially constant, rate so as to widen the region of the centrifuge occupied by the intermediate density component without causing the intermediate density component to exit the centrifuge, and subsequently at a second rate, so as to displace intermediate density component from the centrifuge.