Related Experiment Video
Updated: Oct 23, 2025

Author Spotlight: Deciphering Coagulation Disorders in Traumatic Brain Injury Patients
Published on: August 4, 2023
Time course of coagulation and fibrinolytic parameters in pediatric traumatic brain injury
Ryuta Nakae1, Yu Fujiki2, Yasuhiro Takayama1
111Department of Emergency and Critical Care Medicine, Nippon Medical School, Sendagi, Bunkyo-ku, Tokyo; and.
Insights
Pediatric traumatic brain injury (TBI) patients show prolonged clotting times and lower fibrinogen levels compared to adults. However, elevated D-dimer levels independently predict worse outcomes in children with TBI.
Area of Science:
- Neurotrauma
- Coagulation Science
- Pediatric Critical Care
Background:
- Coagulopathy is a known predictor of poor outcomes in traumatic brain injury (TBI).
- Distinct temporal patterns of coagulation and fibrinolysis in pediatric versus adult TBI patients remain undefined.
- Understanding these differences is crucial for targeted management strategies.
Purpose of the Study:
- To compare the time courses of coagulation and fibrinolytic parameters in pediatric and adult patients following TBI.
- To identify prognostic factors for outcomes in pediatric TBI patients.
Main Methods:
- Retrospective analysis of 468 TBI patients (head AIS score ≥ 3).
- Measurement of prothrombin time (PT)-international normalized ratio (INR), activated partial thromboplastin time (APTT), fibrinogen, and D-dimer at multiple time points post-injury.
- Propensity score matching to compare pediatric (<16 years) and adult (≥16 years) cohorts.
Main Results:
- Pediatric TBI patients exhibited higher PT-INR and APTT, and lower fibrinogen levels within 1-12 hours post-injury compared to adults.
- Elevated D-dimer levels were observed in both groups, with no significant inter-group differences.
- In pediatric TBI, elevated D-dimer was an independent negative prognostic factor for the Glasgow Outcome Scale.
Conclusions:
- Pediatric TBI patients present with distinct acute-phase coagulation profiles (prolonged PT-INR/APTT, lower fibrinogen) compared to adults.
- These coagulation parameter differences did not correlate with outcomes in the pediatric group.
- Elevated D-dimer levels are a significant independent predictor of poor outcomes in pediatric TBI.
Objective:
Coagulopathy is a well-recognized risk factor for poor outcomes in patients with traumatic brain injury (TBI). Differences in the time courses of coagulation and fibrinolytic parameters between pediatric and adult patients with TBI have not been defined.
Methods:
Patients with TBI and an Abbreviated Injury Scale of the head score ≥ 3, in whom the prothrombin time (PT)-international normalized ratio (INR), activated partial thromboplastin time (APTT), fibrinogen concentration, and plasma D-dimer levels were measured on arrival and at 3, 6, and 12 hours after injury, were retrospectively analyzed. Propensity score-matched analyses were performed to adjust baseline characteristics between pediatric patients (aged < 16 years) and adult patients (aged ≥ 16 years).
Results:
A total of 468 patients (46 children and 422 adults) were included. Propensity score matching resulted in a matched cohort of 46 pairs. Higher PT-INR and APTT values at 1 to 12 hours after injury and lower fibrinogen concentrations at 1 to 6 hours after injury were observed in the pediatric group compared with the adult group. Plasma levels of D-dimer were elevated in both groups at 1 to 12 hours after injury, but no significant differences were seen between the groups. Multivariate logistic regression analysis of the initial coagulation and fibrinolytic parameters in the pediatric group revealed no prognostic significance of the coagulation parameter values, but elevation of the fibrinolytic parameter D-dimer was an independent negative prognostic factor.
Conclusions:
In the acute phase of TBI, pediatric patients were characterized by prolongation of PT-INR and APTT and lower fibrinogen concentrations compared with adult patients, but these did not correlate with outcome. D-dimer was an independent prognostic outcome factor in terms of the Glasgow Outcome Scale in pediatric patients with TBI.
Related Concept Videos
Coagulation
During the coagulation phase, clotting factors, or procoagulants, play a vital role in initiating and progressing the coagulation cascade. This cascade is a series of reactions...
Extrinsic and Intrinsic Pathways of Hemostasis
The Extrinsic Pathway
The extrinsic pathway of coagulation is typically initiated by tissue damage that exposes blood to tissue factor (TF), a protein released by the damaged tissue cells outside the blood vessels—this interaction with TF triggers biochemical reactions involving specific clotting factors. The key player here is Factor VII, which...
Clot Retraction and Fibrinolysis

