Overview of therapeutic apheresis
This chapter gives an overview of therapeutic apheresis (TA). Therapeutic apheresis involves the removal of whole blood from a patient, separation of the whole blood into one or more fractions, followed by the removal of the indicated fraction which will be discarded and the infusion of a fluid to replace the lost volume. TA can be performed manually as well as by automated cell separators or apheresis machines. Current apheresis medical devices allow the separation of whole blood into component fractions with the removal of the desired fraction, and return of the remaining components by in-line automated technology. These systems require the use of an anticoagulant solution in order to maintain flow through plastic tubing and the blood-containing centrifuge elements of the devices. Separation of blood components can occur through centrifugation or filtration and operation is with either continuous or intermittent flow. Filtration devices separate component fractions based on the size of the blood component, while plasma flows freely through the filter/membrane.
