title: Traumatic brain injury is not associated with coagulopathy out of proportion to injury in other body regions.
abstract: BACKGROUND
  Coagulopathy following trauma is associated with poor outcomes. Traumatic brain injury has been associated with coagulopathy out of proportion to other body regions. We hypothesized that injury severity and shock determine coagulopathy independent of body region injured.
  
  
  METHODS
  We performed a prospective, multicenter observational study at three Level 1 trauma centers. Conventional coagulation tests (CCTs) and rapid thrombelastography (r-TEG) were used. Admission vital signs, base deficit (BD), CCTs, and r-TEG data were collected. The Abbreviated Injury Scale (AIS) score and Injury Severity Score (ISS) were obtained. Severe injury was defined as AIS score greater than or equal to 3 for each body region. Patients were grouped according to their dominant AIS region of injury. Dominant region of injury was defined as the single region with the highest AIS score. Patients with two or more regions with the same greatest AIS score and patients without a region with an AIS score greater than or equal to 3 were excluded. Coagulation parameters were compared between the dominant AIS region. Significant hypoperfusion was defined as BD greater than or equal to 6.
  
  
  RESULTS
  Of the 795 patients enrolled, 462 met criteria for grouping by dominant AIS region. Patients were predominantly white (59%), were male (75%), experienced blunt trauma (71%), and had a median ISS of 25 (interquartile range, 14-29). Patients with BD greater than or equal to 6 (n = 110) were hypocoagulable by CCT and r-TEG compared with patients with BD less than 6 (n = 223). Patients grouped by dominant AIS region showed no significant differences for any r-TEG or CCT parameter. Patients with BD greater than or equal to 6 demonstrated no difference in any r-TEG or CCT parameter between dominant AIS regions.
  
  
  CONCLUSIONS
  Coagulopathy results from a combination of tissue injury and shock independent of the dominant region of injury. With the use of AIS as a measure of injury severity, traumatic brain injury was not independently associated with more profound coagulopathy.
  
  
  METHODS
  Epidemiologic study, level III.
authors: From the Division of Trauma, Critical Care and Acute Care Surgery, Department of Surgery, Oregon Health and Science University, Portland, Oregon.
authors: Tim H
authors: TH
authors: Lee
authors: David A
authors: DA
authors: Hampton
authors: Brian S
authors: BS
authors: Diggs
authors: Sean P
authors: SP
authors: McCully
authors: Matt
authors: M
authors: Kutcher
authors: Britt J
authors: BJ
authors: Redick
authors: Jeannette
authors: J
authors: Podbielski
authors: Bryan A
authors: BA
authors: Cotton
authors: Mitchell
authors: M
authors: Cohen
authors: Martin A
authors: MA
authors: Schreiber
mesh_terms: D015998:Abbreviated Injury Scale; D001778:Blood Coagulation Disorders / Q000453:epidemiology / Q000209:etiology*; D001780:Blood Coagulation Tests; D001930:Brain Injuries / Q000150:complications*; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D009104:Multiple Trauma; D011446:Prospective Studies; D012307:Risk Factors; D012769:Shock / Q000150:complications; D013916:Thrombelastography