title: Rediscovering the wound hematoma as a site of hemostasis during major arterial hemorrhage.
abstract: BACKGROUND
  Treatments for major internal bleeding after injury include permissive hypotension to decrease the rate of blood loss, intravenous infusion of plasma or clotting factors to improve clot formation, and rapid surgical hemostasis or arterial embolization to control bleeding vessels. Yet, little is known regarding major internal arterial hemostasis, or how these commonly used treatments might influence hemostasis.
  
  
  OBJECTIVE
  (i) To use a swine model of femoral artery bleeding to understand the perivascular hemostatic response to contained arterial hemorrhage. (ii) To directly confirm the association between hemodynamics and bleeding velocity. (iii) To observe the feasibility of delivering an activated clotting factor directly to internal sites of bleeding using a simplified angiographic approach.
  
  
  METHODS
  Ultrasound was used to measure bleeding velocity and in vivo clot formation by elastography in a swine model of contained femoral artery bleeding with fluid resuscitation. A swine model of internal pelvic and axillary artery hemorrhage was also used to demonstrate the feasibility of local delivery of an activated clotting factor.
  
  
  RESULTS
  In this model, clots formed slowly within the peri-wound hematoma, but eventually contained the bleeding. Central hemodynamics correlated positively with bleeding velocity. Infusion of recombinant human activated factor VII into the injured artery near the site of major internal hemorrhage in the pelvis and axillae was feasible.
  
  
  CONCLUSIONS
  We rediscovered that clot formation within the peri-wound hematoma is an integral component of hemostasis and a feasible target for the treatment of major internal bleeding using activated clotting factors delivered using a simplified angiographic approach.
authors.affiliation: Division of Emergency Medicine, University of Washington, Seattle, WA, USA.
authors.forename: N J
authors.initials: NJ
authors.lastname: White
authors.affiliation: Department of Neurological Surgery, University of Washington, Seattle, WA, USA.
authors.forename: E
authors.initials: E
authors.lastname: Mehic
authors.affiliation: Division of Emergency Medicine, University of Washington, Seattle, WA, USA.
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.affiliation: Division of Emergency Medicine, University of Washington, Seattle, WA, USA.
authors.forename: D
authors.initials: D
authors.lastname: Chien
authors.affiliation: Division of Emergency Medicine, University of Washington, Seattle, WA, USA.
authors.forename: E
authors.initials: E
authors.lastname: Lim
authors.affiliation: Division of Emergency Medicine, University of Washington, Seattle, WA, USA.
authors.forename: A E
authors.initials: AE
authors.lastname: St John
authors.affiliation: Division of Emergency Medicine, University of Washington, Seattle, WA, USA.
authors.forename: S A
authors.initials: SA
authors.lastname: Stern
authors.affiliation: Department of Neurological Surgery, University of Washington, Seattle, WA, USA.|Division of Engineering and Mathematics, University of Washington, Bothell, WA, USA.
authors.forename: P D
authors.initials: PD
authors.lastname: Mourad
authors.affiliation: Department of Diagnostic & Interventional Radiology, Medical Clinic Innsbruck, Innsbruck, Austria.
authors.forename: M
authors.initials: M
authors.lastname: Rieger
authors.affiliation: Clinical Department for General and Surgical Intensive Care Medicine of the Clinic for Anaesthesia and General Intensive Care Medicine, Medical Clinic Innsbruck, Innsbruck, Austria.
authors.forename: D
authors.initials: D
authors.lastname: Fries
authors.affiliation: Department for Hematology, TelHashomer University Hospital, Telaviv, Israel.
authors.forename: U
authors.initials: U
authors.lastname: Martinowitz
mesh_terms: D000818:Animals; D001366:Axillary Artery / Q000000981:diagnostic imaging / Q000187:drug effects / Q000503:physiopathology*; D001777:Blood Coagulation; D003029:Coagulants / Q000008:administration & dosage; D004195:Disease Models, Animal; D054459:Elasticity Imaging Techniques; D015942:Factor VIIa / Q000008:administration & dosage; D005240:Feasibility Studies; D005260:Female; D005263:Femoral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006406:Hematoma / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology; D006439:Hemodynamics; D006470:Hemorrhage / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology; D006487:Hemostasis / Q000187:drug effects; D034421:Sus scrofa; D013997:Time Factors; D018608:Ultrasonography, Doppler
chemical_list: D003029:Coagulants; D015942:Factor VIIa
keywords: angiography; coagulopathy; hemorrhage; hemostasis; trauma; ultrasound