Can the 'important brain injury criteria' predict neurosurgical intervention in mild traumatic brain injury? A validation study

Background There is variability in the management of patients presenting to the emergency department (ED) with mild traumatic brain injury (MTBI) and abnormal findings on their initial head computed tomography (CT). The main objective of this study was to validate the value of the Important Brain Injury (IBI) criteria, introduced by the Canadian CT-Head Rule, in predicting the need for surgical intervention. The secondary objective was to identify independent predictors for neurosurgical intervention. Methods This is a post hoc analysis of a prospective cohort of adult patients presenting to the ED of one tertiary care, academic center, between 2008 and 2012, with MTBI and an abnormal initial head CT. Neurosurgical intervention was at the discretion of the treating physician. The sensitivity and specificity of the IBI criteria were calculated with 95% confidence intervals (CI95%). A multivariate logistic regression model was used to identify independent predictors for neurosurgical intervention with the direct entry method. Results A total of 678 patients (male = 65.9%, mean age = 62.5 years) were included, of whom 114 (16.8%) required neurosurgical intervention. All patients requiring neurosurgical intervention met IBI criteria on their initial head CT (sensitivity of 100% [CI95% 96.8–100]). However, 368 (65.2%) patients with findings of IBI did not require neurosurgical intervention (specificity of 34.8% [CI95% 30.8–38.8]). Age over 65 was independently associated with neurosurgical intervention in the IBI population. Conclusion The IBI criteria for MTBI identified all patients who required neurosurgical intervention; however its specificity is low.