Hemapheresis in pregnancy.

Hemapheresis, the removal of part of an individual’s blood with the remainder returned to the individual, is generally as safe in pregnant as in nonpregnant individuals. Three additional conditions, however, are of particular significance to the pregant patient: hemolytic disease of the newborn, increased maternal-fetal mortality in the patient with sickle cell disease; and thrombotic thrombocyopenic purpura and hemolytic uremic syndrome disorders. Topics include technology, plasma and blood volume calculations and considerations, and therapeutic hemapheresis.