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Updated: Mar 5, 2026
Author Spotlight: Deciphering Coagulation Disorders in Traumatic Brain Injury Patients
Published on: August 4, 2023
Characterization of distinct coagulopathic phenotypes in injury: Pathway-specific drivers and implications for
S Ariane Christie1, Lucy Z Kornblith, Benjamin M Howard
1From the Department of Surgery (S.A.C., L.Z.K., B.M.H., A.S.C., R.C.K., M.F.N., C.M.H., C.S.C., R.A.C.), San Francisco General Hospital and the University of California, San Francisco, California; and Denver Health Medical Center and the University of Colorado (M.J.C.), Denver, Colorado.
Background:
International normalized ratio (INR) and partial thromboplastin time (PTT) are used interchangeably to diagnose acute traumatic coagulopathy but reflect disparate activation pathways. In this study, we identified injury/patient characteristics and coagulation factors that drive contact pathway, tissue factor pathway (TF), and common pathway dysfunction by examining injured patients with discordant coagulopathies. We hypothesized that patients with INR/PTT discordance reflect differing phenotypes representing contact versus tissue factor pathway perturbations and that characterization will provide targets to guide individualized resuscitation.
Methods:
Plasma samples were prospectively collected from 1,262 critically injured patients at a single Level I trauma center. Standard coagulation measures and an extensive panel of procoagulant and anticoagulant factors were assayed and analyzed with demographic and outcome data.
Results:
Fourteen percent of patients were coagulopathic on admission. Among these, 48% had abnormal INR and PTT (BOTH), 43% had isolated prolonged PTT (PTT-CONTACT), and 9% had isolated elevated INR (INR-TF). PTT-CONTACT and BOTH had lower Glasgow Coma Scale score than INR-TF (p < 0.001). INR-TF had decreased factor VII activity compared with PTT-CONTACT, whereas PTT-CONTACT had decreased factor VIII activity compared with INR-TF. All coagulopathic patients had factor V deficits, but activity was lowest in BOTH, suggesting an additive downstream effect of disordered activation pathways. Patients with PTT-CONTACT received half as much packed red blood cell and fresh frozen plasma as did the other groups (p < 0.001). Despite resuscitation, mortality was higher for coagulopathic patients; mortality was highest in BOTH and higher in PTT-CONTACT than in INR-TF (71%, 60%, 41%; p = 0.04).
Conclusions:
Discordant phenotypes demonstrate differential factor deficiencies consistent with dysfunction of contact versus tissue factor pathways with additive effects from common pathway dysfunction. Recognition and treatment of pathway-specific factor deficiencies driving different coagulopathic phenotypes in injured patients may individualize resuscitation and improve outcomes.
Level Of Evidence:
Prognostic/epidemiological study, level II.
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