In automated red cell exchange, about 60% of the patient's red blood cells are exchanged via apheresis for those of the donor. We report the outcome of 83 patients with sickle cell anemia (48 women and 35 men; age range, 17-49 years) who underwent a total of 196 apheresis procedures between December 2003 and October 2006 at our institution. We found that automated red cell exchange involving a reduced citrate infusion rate may provide benefit in the prevention or treatment of vaso-occlusive complications in patients with sickle cell disease and may be associated with protean effects on biochemical dynamics.