title: A principal component analysis of coagulation after trauma.
abstract: BACKGROUND
  Clotting factor abnormalities underlying acute traumatic coagulopathy are poorly understood, with application of traditional regression techniques confounded by colinearity. We hypothesized that principal components analysis (PCA), a pattern-finding and data reduction technique, would identify clinically predictive patterns in the complex clotting factor milieu after trauma.
  
  
  METHODS
  Plasma was prospectively collected from 163 critically injured trauma patients. Prothrombin; factors V, VII, VIII, IX, X; D-dimer; activated and native protein C; and antithrombin III levels were assayed and subjected to nonlinear PCA to identify principal components (PCs).
  
  
  RESULTS
  Of 163 patients, 19.0% were coagulopathic on admission. PCA identified 3 significant PCs, accounting for 67.5% of overall variance. PC1 identified global clotting factor depletion; PC2 the activation of protein C and fibrinolysis; and PC3 factor VII elevation and VIII depletion. PC1 score correlated with penetrating injury and injury severity, predicting coagulopathy (odds ratio [OR], 4.67; p < 0.001) and mortality (OR, 1.47; p = 0.032). PC2 score correlated with injury severity, acidosis, and shock, and significantly predicted ventilator-associated pneumonia (OR, 1.59; p = 0.008), acute lung injury (OR, 2.24; p < 0.001), multiorgan failure (OR, 1.83; p = 0.002), and mortality (OR, 1.62; p = 0.006) but was not associated with international normalized ratio (INR)-based or partial thromboplastin time (PTT)-based coagulopathy (p > 0.200). PC3 did not significantly predict outcomes.
  
  
  CONCLUSIONS
  PCA identifies distinct patterns of coagulopathy: depletion coagulopathy predicts mortality and INR/PTT elevation, while fibrinolytic coagulopathy predicts infection, end-organ failure, and mortality, without detectable differences in INR or PTT. While depletion coagulopathy is intuitive, fibrinolytic coagulopathy may be a distinct but often overlapping entity with differential effects on outcomes.
authors.affiliation: Department of Surgery, San Francisco General Hospital, San Francisco, California 94110, USA.
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Kutcher
authors.forename: Adam R
authors.initials: AR
authors.lastname: Ferguson
authors.forename: Mitchell J
authors.initials: MJ
authors.lastname: Cohen
mesh_terms: D000328:Adult; D000990:Antithrombin III / Q000032:analysis; D001778:Blood Coagulation Disorders / Q000097:blood / Q000209:etiology*; D001930:Brain Injuries / Q000097:blood / Q000150:complications; D005164:Factor IX / Q000032:analysis; D005165:Factor V / Q000032:analysis; D005167:Factor VII / Q000032:analysis; D005169:Factor VIII / Q000032:analysis; D005170:Factor X / Q000032:analysis; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis; D006801:Humans; D015601:Injury Severity Score; D025341:Principal Component Analysis; D011446:Prospective Studies; D011486:Protein C / Q000032:analysis; D011516:Prothrombin / Q000032:analysis; D014947:Wounds and Injuries / Q000097:blood / Q000150:complications*; D014950:Wounds, Penetrating / Q000097:blood / Q000150:complications
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; D011486:Protein C; C036309:fibrin fragment D; D000990:Antithrombin III; D005165:Factor V; D005167:Factor VII; D011516:Prothrombin; D005169:Factor VIII; D005164:Factor IX; D005170:Factor X