The association of coagulopathy and traumatic brain injury in patients with isolated head injury

SummaryThe emergence of prothrombotic agents (e.g. activated factor VII) to treat traumatic brain injury (TBI) requires a better understanding of the association of coagulopathy with isolated head injury (IHI).ObjectiveTo investigate the association of IHI and coagulopathy.MethodsProspective, observational study in an urban level I trauma center. Inclusion criteria: Adult (≥13 years of age) patients with IHI. Exclusion criteria: patients with known coagulopathies or on anticoagulant therapy. Predictor Variables: TBI (head abbreviated injury severity score >2, or brain hematoma on CT scan), age, gender, mechanism of injury, Glasgow Coma Score (GCS), and loss of consciousness (LOC). Outcome variables: coagulopathy defined as elevated International Normalized Ratio (INR > 1.3) or activated partial thromboplastin time (PTT) greater than 34 s. We divided IHI subjects into two groups of patients with and without TBI. Statistical Analysis: Fisher's exact test and Mann–Whitney U were used to compare data where appropriate (alpha: 0.05, two-tailed).ResultsFrom July 2005 to December 2006, 276 patients with IHI were studied. The median age was 35 years (interquartile range: 25–52) with a 79% male predominance and 88% blunt trauma. Eight percent (95% CI, 5–12%) of patients had coagulopathy. The rate of coagulopathy in TBI patients (17%) was significantly higher than non-TBI patients (6%) (11% difference, 95% CI, 3–20%]. The relative risk of coagulopathy in TBI patients was 2.9 (95% CI, 1.3–6.6).ConclusionCoagulopathy as defined by elevated INR and/or PTT is associated with TBI after isolated head injury.