Predisposing Factors of Progression from Refractory Status Epilepticus to Super-Refractory Status Epilepticus in ICU-Admitted Patients: Multicenter Retrospective Cohort Study in a Resource-Limited Setting

Background: Super-refractory status epilepticus (SRSE) is an extremely serious neurological emergency. Risk factors and mechanisms involved in transition from refractory status epilepticus (RSE) to SRSE are insufficiently studied. Methods: This was a multicenter retrospective cohort study of consecutive patients diagnosed and treated for RSE at two reference hospital over 5 years in Ecuador. A total of 140 patients were included. Potential demographic, clinical, and treatment variables that may predict progression from refractory to SRSE were analyzed. Results: Super-refractory status epilepticus was identified in 67/140 (48%) of patients. In univariate analyses, level of consciousness on hospital admission (Glasgow Coma Score < 12, odds ratio [OR] 2.9, p < 0.01), traumatic brain injury (OR 2.3, p = 0.05), acute etiology (OR 3.0, p = 0.04), higher Status Epilepticus Severity Score (STESS) (OR 1.7, p < 0.01), and new clinical or electrographic seizure within 6 h (OR 4.2, p < 0.01) of starting anesthetic infusion were important factors related to super-refractory disease. The best independents predictors of SRSE when the presence of other potential factors were considered for multivariate analysis. Two models were calculated to avoid interactions between similar variables. Glasgow Coma Score on hospital admission < 12 (OR 3.1 [95% confidence interval {CI} 1.16–8.29], p = 0.02) and new clinical or electroencephalography (EEG) seizure after first 6 h of starting anesthetic infusion (OR 3.1 [95% CI 1.36–7.09], p = 0.01) were associated with higher risk of progression to SRSE in model 1. In contrast, model 2 indicated that patients with STESS ≥ 3 points (OR 2.9 [95% CI 1.24–6.65], p = 0.01) and new clinical or EEG seizure after 6 h starting anesthetic infusion (OR 3.0 [95% CI 1.32–6.97], p = 0.01) were the factors independently related to super-refractory disease. Conclusions: The rate of patients with RSE admitted to intensive care units developing SRSE was high. Low level of consciousness on admission, higher STESS scores, and patients who did not achieve total control of clinical or EEG seizure in the first 6 h of starting intravenous anesthetic infusion may be early indicators of SRSE.