Related Experiment Video
Updated: Aug 9, 2026

Tail Vein Transection Bleeding Model in Fully Anesthetized Hemophilia A Mice
Published on: September 30, 2021
A critical appraisal of the use of recombinant factor VIIa in acquired bleeding conditions
Sajjan Mittal1, Henry G Watson
1Department of Haematology, Aberdeen Royal Infirmary, Foresterhill, Aberdeen, UK.
Recombinant activated factor VII (rVIIa) was initially used for the treatment of inhibitors in patients with haemophilia. However, its localised mode of action at sites of damage to the vessel combined with dramatic clinical observations in exsanguinating patients have resulted in huge interest in its use as a global haemostatic agent. Although it appears safe, with no obvious excess of thrombotic events, its use in assorted acquired bleeding disorders, especially those associated with the development of complex coagulopathies, such as in the post-trauma state, has proved to be less dramatic than hoped.
Recombinant activated factor VII (rVIIa) was initially used for the treatment of inhibitors in patients with haemophilia. However, its localised mode of action at sites of damage to the vessel combined with dramatic clinical observations in exsanguinating patients have resulted in huge interest in its use as a global haemostatic agent. Although it appears safe, with no obvious excess of thrombotic events, its use in assorted acquired bleeding disorders, especially those associated with the development of complex coagulopathies, such as in the post-trauma state, has proved to be less dramatic than hoped.
Related Concept Videos
Venous Thrombosis III: Interprofessional Care
Anticoagulant Drugs: Low-Molecular-Weight Heparins
Disorders of Hemostasis
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Extrinsic and Intrinsic Pathways of Hemostasis
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which forms a...
