title: Leukoreduction filtration of whole-blood units from sickle trait donors: effects of a metered citrate anticoagulant system.
abstract: BACKGROUND
  Polymerization of hemoglobin (Hb) S is exacerbated by acidic and hyperosmotic citrate anticoagulant solutions and often results in occlusion of leukoreduction filters by red blood cells (RBCs) from sickle cell trait (Hb AS) donors. This study evaluates a blood collection instrument that adds citrate anticoagulant in a metered fashion, thus mitigating adverse citrate effects.
  
  
  METHODS
  Collection of whole blood by a metered anticoagulant system was compared to traditional phlebotomy in 12 Hb AS and 12 non-sickle trait (Hb AA) donors. Each donated twice; on one occasion, units were filtered after 4-hour storage at 20 to 24 degrees C, and on the other, units were stored at 1 to 6 degrees C for 24 hours before filtration.
  
  
  RESULTS
  Filtration times, RBC recoveries, and residual white blood cell (WBC) counts met defined criteria more often in Hb AS units collected by a metered anticoagulant system (9 of 12, 8 of 12, and 4 of 12, respectively) compared to traditional phlebotomy (1 of 12, 2 of 12, and 0 of 12, respectively). Overall, Hb AS units filtered better after storage at 1 to 6 degrees C for 24 hours, with units collected by a metered anticoagulant system undergoing filtration most effectively (5 of 6 had >85% RBC recovery, 3 of 6 had <5 x 10(6) residual WBC). Units exhibited similar changes in RBC storage parameters.
  
  
  CONCLUSIONS
  Use of a metered anticoagulation instrument demonstrates potential for successful leukoreduction and acceptable storage of Hb AS units; however, the system needs further modifications and improvements before it can be utilized to collect and leukoreduce Hb AS blood.
authors: Department of Transfusion Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, Maryland 20892, USA. bryantb2@cc.nih.gov
authors: Barbara J
authors: BJ
authors: Bryant
authors: Maria
authors: M
authors: Bianchi
authors: Robert A
authors: RA
authors: Wesley
authors: David F
authors: DF
authors: Stroncek
authors: Susan F
authors: SF
authors: Leitman
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000494:pharmacology; D001782:Blood Donors; D001793:Blood Preservation / Q000295:instrumentation / Q000379:methods; D019343:Citric Acid / Q000494:pharmacology; D005374:Filtration / Q000379:methods; D006801:Humans; D007958:Leukocyte Count; D047589:Leukocyte Reduction Procedures / Q000295:instrumentation / Q000379:methods*; D008875:Middle Aged; D012805:Sickle Cell Trait / Q000097:blood*
chemical_list: D000925:Anticoagulants; D019343:Citric Acid