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Updated: Aug 17, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
13:08

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Published on: September 9, 2012

The factor VII-platelet interplay: effectiveness of recombinant factor VIIa in the treatment of bleeding in severe

D M Monroe1, M Hoffman, G A Allen

  • 1Center for Thrombosis and Hemostasis, UNC School of Medicine, Chapel Hill, North Carolina, USA. dmonroe@med.unc.edu

Seminars in Thrombosis and Hemostasis
|November 25, 2000
PubMed

Recently, high-dose factor VIIa has been used to correct bleeding in patients with various thrombocytopathias including Glanzmann's thrombasthenia, Bernard-Soulier syndrome, and uremia. High-dose factor VIIa is postulated to act on platelets in the absence of tissue factor to activate factors IX and X and thus enhance thrombin generation. This enhanced thrombin generation might help provide hemostasis in patients with thrombocytopathias through several mechanisms. Enhanced thrombin generation would provide a strong signal for recruitment of other platelets. Also, enhanced fibrin deposition might provide mechanisms for bypassing the specific defect in thrombocytopathias. Thus, platelets from a patient with Bernard-Soulier syndrome might associate with fibrin by a glycoprotein IIb-IIIa-mediated mechanism. Also, platelets from a patient with Glanzmann's thrombasthenia might associate with fibrin through von Willebrand factor-mediated interactions with glycoprotein Ib-V-IX. Finally, enhanced thrombin generation on platelets would mean that fewer platelets are required for hemostasis.

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