Should FFP Administration Be Weight-Based?
Yes, FFP administration should be weight-based, with the standard recommended dose of 10-15 ml/kg body weight for patients with massive bleeding or significant bleeding complicated by coagulopathy. 1, 2
Standard Weight-Based Dosing
The weight-based approach is consistently recommended across major guidelines:
- Initial dose: 10-15 ml/kg is the most frequently recommended starting dose for correction of coagulopathy with bleeding 1, 2
- For a 70 kg adult, this translates to approximately 700-1,050 ml or 3-4 units of FFP (each unit contains 250-300 ml) 2
- This dosing achieves the critical threshold of at least 30% concentration of plasma coagulation factors needed for hemostasis 2, 3
Clinical Context for Weight-Based Dosing
FFP is indicated when:
- PT > 1.5 times control or INR > 2.0 1, 3
- aPTT > 2 times control with active bleeding 1, 3
- Massive transfusion (>1 blood volume or ~70 ml/kg) with ongoing bleeding 2
Why Weight-Based Dosing Matters
Doses below 10 ml/kg are unlikely to be effective because they fail to achieve the 30% factor concentration threshold required for hemostasis 2. This is a critical pitfall—underdosing FFP wastes a scarce resource while exposing patients to transfusion risks without therapeutic benefit.
Special Dosing Scenarios
- Urgent warfarin reversal: Lower doses of 5-8 ml/kg are usually sufficient (approximately 1-2 units for most adults) 2, 3
- Factor X deficiency: Higher initial dose of 20 ml/kg followed by 3-6 ml/kg twice daily may be required 2
- Massive hemorrhage: May require doses exceeding the initial 10-15 ml/kg, with additional doses guided by repeat coagulation testing 1, 2
Monitoring and Repeat Dosing
- Recheck coagulation parameters after transfusion to determine need for additional doses 2
- Further doses may be required beyond the initial weight-based dose, particularly in ongoing massive bleeding 1
- The goal is correction of coagulopathy (PT/INR and aPTT normalization), not a fixed total volume 1, 2
Important Caveats
Do not use FFP for prophylactic correction of mild coagulopathy in non-bleeding patients—this practice is unsupported by evidence and unnecessarily exposes patients to serious risks including TRALI, circulatory overload, and infectious disease transmission 1, 2, 4. FFP should be reserved for active bleeding with documented coagulopathy or massive transfusion scenarios 1, 2.
FFP has relatively low fibrinogen content (four units contain only approximately 2 g fibrinogen), making it inefficient for isolated hypofibrinogenemia—use cryoprecipitate or fibrinogen concentrate instead when fibrinogen <1.5 g/L 2, 5.