title: Abnormal coagulation tests are associated with progression of traumatic intracranial hemorrhage.
abstract: BACKGROUND
  Intracranial hemorrhage (ICH) is common in traumatic brain injury (TBI) and a major determinant of death and disability. ICH commonly increases in size and coagulopathy has been implicated in such progression. We investigated the association between coagulopathy diagnosed by routine laboratory tests and ICH progression.
  
  
  METHODS
  Subgroup post hoc analysis from a randomized controlled trial including adult patients with blunt severe TBI (Glasgow Coma Scale score <or=8) and repeat computerized tomography scans in 48 hours. Coagulopathy was defined as international normalized ratio >or=1.3, activated partial thromboplastin time >or=35, or platelet count (PLT) <or=100 x 10/L any time in the first 24 hours. Progression was any size increase or new ICH. TBI-associated coagulopathy was investigated measuring soluble tissue factor (TF) and d-dimer.
  
  
  RESULTS
  The ICH progressed in 37 of 72 patients (51%), in 80% if any abnormal laboratory test (coagulopathic patients) versus 36% in noncoagulopathic (p = 0.0004). Abnormal international normalized ratio (odds ratio [OR] = 4.09; 95% confidence interval [CI] = 1.29-12.95; p = 0.017), PLT (OR = 12.59; 95% CI = 1.52-108.57; p = 0.019), head Abbreviated Injury Scale (AIS) (OR = 1.82; 95% CI = 1.15-2.88; p = 0.011) were significantly associated with progression (univariate analysis). In a multiple logistic regression, only head AIS (OR = 1.81; 95% CI 1.10-2.98; p = 0.0198) and PLT (OR = 11.8; 95% CI = 1.38-101.23; p = 0.024) correlated with progression. All patients with abnormal partial thromboplastin time experienced progression. ICH progression carried a 5-fold higher odds of death; 32% with progression died versus 8.6% without. Age, head AIS, Injury Severity Score, and d-dimer were also associated with mortality. Tissue factor was not associated with progression or mortality.
  
  
  CONCLUSIONS
  This study demonstrates an association between coagulopathy, diagnosed by routine laboratorial tests in the first 24 hours, with ICH progression; and ICH progression with mortality in patients with severe TBI. The causal relationship between coagulopathy and ICH progression will require further studies.
authors.affiliation: Department of Surgery and/or Critical Care Medicine, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Allard
authors.forename: Sandro
authors.initials: S
authors.lastname: Scarpelini
authors.forename: Shawn G
authors.initials: SG
authors.lastname: Rhind
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Baker
authors.forename: Pang N
authors.initials: PN
authors.lastname: Shek
authors.forename: Homer
authors.initials: H
authors.lastname: Tien
authors.forename: Michael
authors.initials: M
authors.lastname: Fernando
authors.forename: Lorraine
authors.initials: L
authors.lastname: Tremblay
authors.forename: Laurie J
authors.initials: LJ
authors.lastname: Morrison
authors.forename: Ruxandra
authors.initials: R
authors.lastname: Pinto
authors.forename: Sandro B
authors.initials: SB
authors.lastname: Rizoli
mesh_terms: D000328:Adult; D001778:Blood Coagulation Disorders / Q000209:etiology / Q000503:physiopathology*; D001780:Blood Coagulation Tests; D018450:Disease Progression; D005260:Female; D016489:Head Injuries, Closed / Q000097:blood*; D006801:Humans; D020198:Intracranial Hemorrhage, Traumatic / Q000097:blood* / Q000150:complications; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010314:Partial Thromboplastin Time; D055815:Young Adult