Hemostatic effects of fresh frozen plasma may be maximal at red cell ratios of 1:2

J Trauma. 2011 Jan;70(1):90-5; discussion 95-6. doi: 10.1097/TA.0b013e318202e486.


Background: Damage control resuscitation targets acute traumatic coagulopathy with the early administration of high-dose fresh frozen plasma (FFP). FFP is administered empirically and as a ratio with the number of packed red blood cells (PRBC). There is controversy over the optimal FFP:PRBC ratio with respect to outcomes, and their hemostatic effects have not been studied. We report preliminary findings on the effects of different FFP:PRBC ratios on coagulation.

Methods: This is a prospective observational cohort study of trauma patients requiring >4 U of PRBCs. Blood was drawn before and after each 4-U PRBC interval for prothrombin time and analysis by rotational thromboelastometry. Interval change in coagulation parameters were compared with the FFP:PRBC ratio received during each interval.

Results: Sixty 4-U PRBC intervals from 50 patients were available for analysis. All measures of coagulation deteriorated with low FFP:PRBC ratios (<1:2). Maximal hemostatic effect was observed in the 1:2 to 3:4 group: 12% decrease in prothrombin time (p=0.006), 56% decrease in clotting time (p=0.047), and 38% increase in maximum clot firmness (p=0.024). Transfusion with ≥1:1 ratio did not confer any additional improvement. There was a marked variability in response to FFP, and hemostatic function deteriorated in some patients exposed to 1:1 ratios. The beneficial effects of plasma were confined to patients with coagulopathy.

Conclusions: Interim results from this prospective study suggest that FFP:PRBC ratios of ≥1:1 do not confer any additional advantage over ratios of 1:2 to 3:4. Hemostatic benefits of plasma therapy are limited to patients with coagulopathy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Blood Coagulation / physiology
  • Blood Transfusion / methods
  • Blood Transfusion / standards
  • Erythrocyte Count*
  • Female
  • Hemorrhage / therapy
  • Hemostasis / physiology*
  • Humans
  • Male
  • Middle Aged
  • Plasma / physiology*
  • Prothrombin Time
  • Thrombelastography
  • Treatment Outcome
  • Wounds and Injuries / therapy*