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Coagulation Factor Replacement — Hypofibrinogenaemia Pregnancy: Use if clinically indicated — essential in obstetric haemorrhage when fibrinogen critically low; monitor closely

Fibrinogen Concentrate

Brand names: Riastap, Fibryga

Adult dose

Dose: Congenital hypofibrinogenaemia: 70 mg/kg IV. Acquired (bleeding/surgery): titrated to target fibrinogen ≥1.5–2 g/L; dose = (target − measured) × 0.035 × body weight
Route: IV injection
Frequency: As required (on-demand) or prophylactically in congenital deficiency
Max: 70 mg/kg (initial dose); adjust based on fibrinogen levels
Used for congenital afibrinogenaemia/hypofibrinogenaemia and acquired fibrinogen deficiency (massive haemorrhage, DIC, obstetric haemorrhage, liver failure). Target fibrinogen ≥1.5 g/L in bleeding patients; ≥2 g/L in obstetric haemorrhage.

Paediatric dose

Dose: 70 mg/kg mg/kg
Route: IV
Frequency: As required
Max: Per clinical response and fibrinogen target
BNFc: neonates and children — dose as per adult calculation based on target fibrinogen level and body weight

Dose adjustments

Renal

No dose adjustment required

Hepatic

Use with caution; hepatic failure may cause ongoing depletion requiring repeated dosing

Paediatric weight-based calculator

BNFc: neonates and children — dose as per adult calculation based on target fibrinogen level and body weight

Clinical pearls

  • WOMAN trial (2017): tranexamic acid is first-line haemostatic agent in PPH — fibrinogen concentrate used adjunctively when fibrinogen <2 g/L
  • Cryoprecipitate provides ~0.25 g fibrinogen per unit (in 15–30 mL) — fibrinogen concentrate is virally inactivated and more consistent in fibrinogen content
  • Obstetric haemorrhage: fibrinogen levels fall rapidly in PPH — fibrinogen <2 g/L predicts severe PPH (FIGO 2022)
  • FibPPH trial and OBS2 study: point-of-care viscoelastic testing (ROTEM/TEG) guides targeted fibrinogen replacement in PPH
  • In massive haemorrhage protocol: transfuse in 1:1:1 ratio (RBC:FFP:platelets); add fibrinogen concentrate or cryoprecipitate if fibrinogen <1.5 g/L
  • Check fibrinogen level immediately before and after administration to confirm response

Contraindications

  • Known hypersensitivity to human plasma proteins
  • Active thrombotic or thromboembolic disease (relative)

Side effects

  • Thromboembolism (rare — risk increases with high fibrinogen levels)
  • Allergic reactions
  • Fever
  • Anaphylaxis (rare)

Interactions

  • No clinically significant drug interactions

Monitoring

  • Fibrinogen level (before and after administration)
  • Clinical haemostasis
  • Thromboembolic symptoms
  • FBC

Reference: BNFc; BNF 90; BNFc; WOMAN Trial (Lancet 2017); RCOG PPH Guidelines 2022; BSH Transfusion Guidelines. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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