D-dimer as a predictor of progressive hemorrhagic injury in patients with traumatic brain injury: analysis of 194 cases

This study sought to describe and evaluate any relationship between D-dimer values and progressive hemorrhagic injury (PHI) after traumatic brain injury (TBI). In patients with TBI, plasma D-dimer was measured while a computed tomography (CT) scan was conducted as soon as the patient was admitted to the emergency department. A series of other clinical and laboratory parameters were also measured and recorded. A logistic multiple regression analysis was used to identify risk factors for PHI. A cohort of 194 patients with TBI was evaluated in this clinical study. Eighty-one (41.8%) patients suffered PHI as determined by a second CT scan. The plasma D-dimer level was higher in patients who demonstrated PHI compared with those who did not (P < 0.001. Using a receiver–operator characteristic curve to predict the possibility by measuring the D-dimer level, a value of 5.00 mg/L was considered the cutoff point, with a sensitivity of 72.8% and a specificity of 78.8%. Eight-four patients had D-dimer levels higher than the cut point value (5.0 mg/L); PHI was seen in 71.4% of these patients and in 19.1% of the other patients (P < 0.01). Factors with P < 0.2 on bivariate analysis were included in a stepwise logistic regression analysis to identify independent risk factors for TBI coagulopathy. Logistic regression analysis showed that the D-dimer value was a predictor of PHI, and the odds ratio (OR) was 1.341 with per milligram per liter (P = 0.020). The stepwise logistic regression also identified that time from injury to the first CT shorter than 2 h (OR = 2.118, P = 0.047), PLT counts lesser than 100 × 109/L (OR = 7.853, P = 0.018), and Fg lower than 2.0 g/L (OR = 3.001, P = 0.012) were risk factors for the development of PHI. When D-dimer values were dichotomized at 5 mg/L, time from injury to the first CT scan was no longer a risk factor statistically while the OR value of D-dimer to the occurrence of PHI elevated to 11.850(P < 0.001). The level of plasma D-dimer after TBI can be a useful prognostic factor for PHI and should be considered in the clinical management of patients in combination with neuroimaging and other data.