Altered mental status in moderate-severe traumatic brain injury in Indonesia: the clinical manifestation and EEG features of non-convulsive status epilepticus

INTRODUCTION: Moderate-to-severe traumatic brain injury (msTBI) can cause non-convulsive status epilepticus (NCSE). Electroencephalography (EEG) is employed as a diagnostic tool due to the non-specificity of clinical symptoms. This study aimed to identify clinical and EEG features related to NCSE in patients with msTBI. METHODS: This was a cross-sectional study. Suspected NCSE in msTBI was examined using EEG data collected in consecutive patients from January 2017 to December 2019 at Dr. Cipto Mangunkusumo Hospital, Jakarta. Diagnoses of NCSE were made based on clinical manifestations and EEG features using the modified Salzburg Consensus Criteria for NCSE (mSCNC). RESULTS: Of the 39 msTBI patients, 19 were diagnosed with NCSE; only two fulfilled the definitive criteria, and the remaining were possible NCSE. Delirium and perceptual impairment were only found in NCSE, while psychomotor agitation was higher (12.8% vs. 5.1% in NCSE vs. non-NCSE). The most common EEG feature was rhythmic activity (>0.5 Hz) without fluctuation, which improved with anti-epileptic drug administration. The Glasgow Coma Scale (GCS) score at onset and at hospitalisation discharge was significantly lower in patients with NCSE. The lesions in NCSE mostly originated from the temporal lobe. Injury to the temporal lobe had a significant relationship with NCSE occurrence (p = 0.036, odds ratio 11.45 [95% confidence interval 1.17–111.6]). DISCUSSION: Post-traumatic NCSE can manifest as an alteration in mental status that could lead to missed diagnosis. In this study, delirium, perceptual impairment, and psychomotor agitation were confirmed as NCSE using EEG. The most common discharge originated from the injured temporal lobe, and this site was a significant factor associated with NCSE in patients with msTBI. CONCLUSION: NCSE can be found in msTBI cases with clinical manifestations of altered mental status, psychomotor agitation, and hallucination. An injured temporal lobe was a susceptible site for the development of NCSE.