title: Fresh frozen plasma: red blood cells (1:2) coagulation effect is equivalent to 1:1 and whole blood.
abstract: BACKGROUND
  Preemptive treatment of trauma-associated coagulopathy involves transfusion of fresh frozen plasma (FFP) at 1:1 ratio with red blood cells (RBCs), but the optimal ratio remains controversial. In combat theaters, fresh whole blood (FWB) is also an option. The objective of this study was to determine the effect of FFP:RBC ratios 1:1, 1:2, 1:3 and FWB on coagulation during resuscitation.
  
  
  METHODS
  Thirty-six rats were randomized in the following six groups: Group 1: sham; Group 2: hemorrhage followed by sole lactated Ringer (LR) infusion; Group 3: FFP:RBC (1:1); Group 4: FFP:RBC (1:2); Group 5: FFP:RBC (1:3); Group 6: FWB transfusion. Another 25 animals were used for blood harvesting. Hemorrhage was induced by withdrawing 40% of total blood volume, mean arterial pressure (MAP) decreased to 45% of baseline, and laparotomy. Animals underwent LR infusion followed by blood product transfusion preset for each group. Blood samples were obtained at baseline and in the 105th minute for thromboelastometry and lactate.
  
  
  RESULTS
  Hemorrhage caused a significant decrease in MAP and increase in lactate (P < 0.05). MAP was persistently low in group 2 despite fluid infusion (P < 0.05), but not in the other groups after 20 min of resuscitation. Mean clot formation time, alpha angle, and maximum clot firmness decreased significantly (P < 0.05) in group 2 (LR) and group 5 (1:3) compared with other groups.
  
  
  CONCLUSIONS
  FFP:RBC in a 1:2 ratio optimally harnessed hemostatic resuscitation and prudent use of blood products compared with 1:1 and 1:3 ratios and to FWB transfusion.
authors.affiliation: Division of General Surgery, Department of Surgery, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada. Electronic address: rezendenetoj@smh.ca.
authors.forename: Joao B
authors.initials: JB
authors.lastname: Rezende-Neto
authors.affiliation: Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Gilberto P
authors.initials: GP
authors.lastname: Rodrigues
authors.affiliation: Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Thiago A
authors.initials: TA
authors.lastname: Lisboa
authors.affiliation: Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Mario
authors.initials: M
authors.lastname: Carvalho-Junior
authors.affiliation: Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Maria Julia
authors.initials: MJ
authors.lastname: Silva
authors.affiliation: Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Marcus V
authors.initials: MV
authors.lastname: Andrade
authors.affiliation: Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Sandro B
authors.initials: SB
authors.lastname: Rizoli
authors.affiliation: Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Jose R
authors.initials: JR
authors.lastname: Cunha-Melo
mesh_terms: D000818:Animals; D017707:Erythrocyte Transfusion / Q000379:methods*; D006439:Hemodynamics; D008297:Male; D010949:Plasma; D011897:Random Allocation; D017208:Rats, Wistar; D012151:Resuscitation / Q000379:methods*; D012771:Shock, Hemorrhagic / Q000628:therapy*
keywords: Coagulopathy; Hemorrhage; Plasma; Shock; Transfusion; Trauma