Secondary Neurologic Deterioration After Moderate Traumatic Brain Injury: Development of a Multivariable Prediction Model and Proposition of a Simple Triage Score

Abstract

BACKGROUND: Identifying patients at risk of secondary neurologic deterioration (SND) after moderate traumatic brain injury (moTBI) is a challenge, as such patients will need specific care. No simple scoring system has been evaluated to date. This study aimed to determine clinical and radiological factors associated with SND after moTBI and to propose a triage score. METHODS: All adults admitted in our academic trauma center between January 2016 and January 2019 for moTBI (Glasgow Coma Scale [GCS] score, 9–13) were eligible. SND during the first week was defined either by a decrease in GCS score of >2 points from the admission GCS in the absence of pharmacologic sedation or by a deterioration in neurologic status associated with an intervention, such as mechanical ventilation, sedation, osmotherapy, transfer to the intensive care unit (ICU), or neurosurgical intervention (for intracranial mass lesions or depressed skull fracture). Clinical, biological, and radiological independent predictors of SND were identified by logistic regression (LR). An internal validation was performed using a bootstrap technique. A weighted score was defined based on beta (β) coefficients of the LR. RESULTS: A total of 142 patients were included. Forty-six patients (32%) showed SND, and 14-day mortality rate was 18.4%. Independent variables associated with SND were age above 60 years (odds ratio [OR], 3.45 [95% confidence interval {CI}, 1.45–8.48]; P = .005), brain frontal contusion (OR, 3.22 [95% CI, 1.31–8.49]; P = .01), prehospital or admission arterial hypotension (OR, 4.86 [95% CI, 2.03–12.60]; P = .006), and a Marshall computed tomography (CT) score of 6 (OR, 3.25 [95% CI, 1.31–8.20]; P = .01). The SND score was defined with a range from 0 to 10. The score included the following variables: age >60 years (3 points), prehospital or admission arterial hypotension (3 points), frontal contusion (2 points), and Marshall CT score of 6 (2 points). The score was able to detect patients at risk of SND, with an area under the receiver operating characteristic curve (AUC) of 0.73 (95% CI, 0.65–0.82). A score of 3 had a sensitivity of 85%, a specificity of 50%, a VPN of 87%, and a VPP of 44 % to predict SND. CONCLUSIONS: In this study, we demonstrate that moTBI patients have a significant risk of SND. A simple weighted score at hospital admission could be able to detect patients at risk of SND. The use of the score may enable optimization of care resources for these patients.