title: Multiple levels of degradation diminish hemostatic potential of thawed plasma.
abstract: BACKGROUND
  Severe bleeding after injury requires transfusion of blood products, including fresh frozen plasma (FFP). Many centers are keeping thawed plasma (TP) ready for massively transfused patients. According to the American Association of Blood Banks Standards, TP is approved for transfusion up to 5 days after thawing, when stored at 1°C to 6°C. However, there are no clinical data analyzing the effects of the approved 5-day storage on plasma. We hypothesize that the hemostatic potential (HP) of freshly thawed (FFP-0) was superior to plasma stored for 5 days (FFP-5).
  
  
  METHODS
  FFP from 30 single donors were thawed at 37°C and kept at 1°C to 6°C for 5 days. HP was evaluated at day 0 and 5 by measuring kinetics of thrombin generation (TG), kinetics of clot formation by thromboelastography, clotting factors and inhibitors, and cell-derived microparticles (MPs) by flow cytometry.
  
  
  RESULTS
  When comparing FFP-5 to FFP-0, FFP-5 exhibited only 40% of the potential of FFP-0 for TG (6.2 nM/min vs. 14.3 nM/min, p<0.0001), a slower clotting response via thromboelastography (reaction time: 4.3 minutes vs. 3.2 minutes, p<0.0001) and a longer delay in reaching maximum thrombus generation (5.7 minutes vs. 4.6 minutes, p<0.01). Diminished HP was accompanied by a significant decline in multiple coagulation proteins, including FV, VII, VIII, von Willebrand factor, and free Protein S, by up to 30%, and a decrease of 50% in MP counts.
  
  
  CONCLUSIONS
  The HP and clot forming ability of TP significantly declined with storage. Hence, freshly TP may have a greater ability to restore hemostasis and correct coagulopathy compared with FFP-5. The clinical consequences for transfused patients deserve further exploration.
authors.affiliation: Department of Surgery and Center for Translational Injury Research, University of Texas Health Science Center-Houston, Houston, Texas 77030, USA. nevenka.matijevic-aleksic@uth.tmc.edu
authors.forename: Nena
authors.initials: N
authors.lastname: Matijevic
authors.forename: Vadim
authors.initials: V
authors.lastname: Kostousov
authors.forename: Yao-Wei W
authors.initials: YW
authors.lastname: Wang
authors.forename: Charles E
authors.initials: CE
authors.lastname: Wade
authors.forename: Weiwei
authors.initials: W
authors.lastname: Wang
authors.forename: Phillip
authors.initials: P
authors.lastname: Letourneau
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hartwell
authors.forename: Rosemary
authors.initials: R
authors.lastname: Kozar
authors.forename: Tien
authors.initials: T
authors.lastname: Ko
authors.forename: John B
authors.initials: JB
authors.lastname: Holcomb
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001777:Blood Coagulation / Q000502:physiology; D001779:Blood Coagulation Factors / Q000032:analysis; D005260:Female; D005434:Flow Cytometry; D006470:Hemorrhage / Q000097:blood / Q000628:therapy; D006487:Hemostasis / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010314:Partial Thromboplastin Time; D010949:Plasma / Q000502:physiology*; D011517:Prothrombin Time; D013916:Thrombelastography; D013997:Time Factors; D055815:Young Adult
chemical_list: D001779:Blood Coagulation Factors