Study objective: Determine the impact of varying doses of fibrinogen concentrate and 4-factor prothrombin complex concentrate on clotting time as measured by thromboelastometry in an in-vitro model of dilutional coagulopathy. Design: In-Vitro Study. Setting: Tertiary academic center. Patients: 31 healthy term singleton gestation patients. Interventions: Blood was analyzed and diluted 95% with crystalloid. Washed red blood cells were added to simulate red blood cell transfusion. Two levels of fibrinogen repletion were then added to samples to simulate fibrinogen repletion in massive transfusion. Finally, 4-factor prothrombin complex concentrate (10 U/kg, 15 U /kg, or 25 U/kg) adjusted for body weight and estimated blood volume was added. Measurements: Samples were analyzed by thromboelastometry, and the main outcome was a FIBTEM clotting time > 80s. Main results: FIBTEM clotting times were prolonged after dilution. After repletion with fibrinogen and prothrombin complex concentrates 7/31 (22.5%) of samples had a prolonged FIBTEM clotting time (> 80s) in the 50% fibrinogen repletion arm and 0 (0%) had a prolonged clotting time in the 100% fibrinogen repletion arm. FIBTEM clotting times approached their baseline levels at each dose of prothrombin complex concentrate. Median clotting time in the 100% fibrinogen repletion arm was under 80s prior to the administration of prothrombin complex concentrate. Conclusions: Commonly cited doses for prothrombin complex concentrates in hemorrhage might be too high for the obstetric patient. After fibrinogen correction alone, several samples required no further correction, highlighting the importance of frequent testing at the point of care. Limitations of this study include the in vitro study design and ability to directly apply findings to patient care. Further studies are needed to elucidate the ideal dose of prothrombin complex concentrate for obstetric hemorrhage. Tweetable abstract: Fibrinogen concentrate and low dose 4-factor PCC corrected coagulopathy in in-vitro obstetric hemorrhage.
- Fibrinogen concentrate
- Obstetric hemorrhage
- Prothrombin complex concentrate