title: A principal component analysis of postinjury viscoelastic assays: clotting factor depletion versus fibrinolysis.
abstract: BACKGROUND
  The mechanisms driving trauma-induced coagulopathy (TIC) remain to be defined, and its therapy demands an orchestrated replacement of specific blood products. Thrombelastography (TEG) is a tool to guide the TIC multicomponent therapy. Principal component analysis (PCA) is a statistical approach that identifies variable clusters; thus, we hypothesize that PCA can identify specific combinations of TEG-generated values that reflect TIC mechanisms.
  
  
  METHODS
  Adult trauma patients admitted from September 2010 to October 2013 for whom a massive transfusion protocol was activated were included. Rapid TEG values obtained within the first 6 hours after injury were included in the PCA. PCA components with an eigenvalue >1 were retained, and, within components, variable loadings (equivalent to correlation coefficients) >|60| were considered significant. Component scorings for each patient were calculated and clinical characteristics of patients with high and low scores were compared.
  
  
  RESULTS
  Of 98 enrolled patients, 67% were male and 70% suffered blunt trauma. Median age was 41 years (interquartile range 28-55) and median Injury Severity Score was 31.5 (interquartile range 24-43). PCA identified three principal components (PCs) that together explained 93% of the overall variance. PC1 reflected global coagulopathy with depletion of platelets and fibrinogen whereas PC3 indicated hyperfibrinolysis. PC2 may represent endogenous anticoagulants such as the activation of protein C.
  
  
  CONCLUSIONS
  PCA suggests depletion coagulopathy is independent from fibrinolytic coagulopathy. Furthermore, the distribution of mortality suggests that low levels of fibrinolysis may be beneficial in a select group of injured patients. These data underscore the potential of risk for concurrent presumptive treatment for preserved depletion coagulopathy and possible fibrinolysis.
authors: University of Colorado Denver, Denver, CO.
authors: Theresa L
authors: TL
authors: Chin
authors: University of Colorado Denver, Denver, CO; Denver Health Medical Center, Denver, CO. Electronic address: ernest.moore@dhha.org.
authors: Ernest E
authors: EE
authors: Moore
authors: University of Colorado Denver, Denver, CO.
authors: Hunter B
authors: HB
authors: Moore
authors: University of Colorado Denver, Denver, CO.
authors: Eduardo
authors: E
authors: Gonzalez
authors: University of Colorado Denver, Denver, CO.
authors: Michael P
authors: MP
authors: Chapman
authors: University of Colorado Denver, Denver, CO.
authors: John R
authors: JR
authors: Stringham
authors: University of Colorado Denver, Denver, CO.
authors: Christopher R
authors: CR
authors: Ramos
authors: University of Colorado Denver, Denver, CO.
authors: Anirban
authors: A
authors: Banerjee
authors: University of Colorado Denver, Denver, CO.
authors: Angela
authors: A
authors: Sauaia
mesh_terms: D000328:Adult; D001778:Blood Coagulation Disorders / Q000097:blood* / Q000209:etiology* / Q000628:therapy; D001779:Blood Coagulation Factors / Q000378:metabolism*; D016913:Blood Component Transfusion; D005260:Female; D005342:Fibrinolysis; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D025341:Principal Component Analysis; D012151:Resuscitation; D013916:Thrombelastography / Q000379:methods* / Q000706:statistics & numerical data; D014947:Wounds and Injuries / Q000097:blood* / Q000150:complications*
chemical_list: D001779:Blood Coagulation Factors