title: Mechanism of injury affects acute coagulopathy of trauma in combat casualties.
abstract: BACKGROUND
  Recent evidence suggests trauma involving total body tissue damage increases the acute coagulopathy of trauma (ACOT) by various mechanisms, especially in massive transfusion (MT). Our hypothesis was that MT patients injured by explosion will have a higher international normalization ratio (INR) at admission than MT patients injured by gunshot wound (GSW).
  
  
  METHODS
  A retrospective review was performed on US military injured in Operation Iraqi Freedom/Operation Enduring Freedom from March 2003 to September 2008, who received MT (≥ 10 red blood cells in 24 hours) and had an INR on admission. Two cohorts were created based on mechanism. Admission vital signs, labs, transfusion, and mortality data were compared.
  
  
  RESULTS
  Seven hundred fifty-one MT patients were identified. Four hundred fifty patients had admission INR and were injured by either GSW or explosion. Patients demonstrated similar injury severity scale and Glasgow Coma Scale. Patients injured by explosion presented with higher INR, greater base deficit, and more tachycardic than patients injured by GSW. Transfusion of blood products was similar between both groups.
  
  
  CONCLUSIONS
  The primary finding of this study is that patients injured by explosion presented with a higher INR than those injured by GSW, even with similar injury severity scale. In addition, patients injured by explosion presented more tachycardic and with a greater base deficit. These findings support the theory that ACOT is affected by the amount of tissue injured. Further research is needed into the pathophysiology of ACOT because this may impact care of patients with total body tissue damage/hypoxia and improve the treatment of their coagulopathy while minimizing the attendant complications.
authors.affiliation: United States Army Institute of Surgical Research, San Antonio, Texas 78234, USA.
authors.forename: John W
authors.initials: JW
authors.lastname: Simmons
authors.forename: Christopher E
authors.initials: CE
authors.lastname: White
authors.forename: John D
authors.initials: JD
authors.lastname: Ritchie
authors.forename: Mark O
authors.initials: MO
authors.lastname: Hardin
authors.forename: Michael A
authors.initials: MA
authors.lastname: Dubick
authors.forename: Lorne H
authors.initials: LH
authors.lastname: Blackbourne
mesh_terms: D000208:Acute Disease; D000328:Adult; D055826:Afghan Campaign 2001-; D001777:Blood Coagulation; D001778:Blood Coagulation Disorders / Q000097:blood / Q000209:etiology*; D001803:Blood Transfusion; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D019934:International Normalized Ratio; D054542:Iraq War, 2003-2011; D008297:Male; D012189:Retrospective Studies; D014947:Wounds and Injuries / Q000097:blood* / Q000209:etiology; D055815:Young Adult