EEG Patterns Predicting Clobazam Response in Refractory Status Epilepticus in Adults
Article Category: Brief communication
Publicado en línea: 20 jul 2024
Páginas: 9 - 12
Recibido: 07 may 2024
Aceptado: 24 jun 2024
DOI: https://doi.org/10.2478/joepi-2024-0002
Palabras clave
© 2024 Arichena Manmatharayan et al., published by Sciendo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Background
Seizure resolution is often difficult to attain promptly in status epilepticus (SE). Clobazam (CLB) is structurally different from typical benzodiazepines with an affinity to the α2 subunit of GABA-A receptors, rendering unique efficacy in seizure termination.
Aim
To assess the response of clobazam in refractory status epilepticus (RSE) and to correlate this response with EEG patterns.
Materials and Methods
This was a single-center retrospective study conducted at a neurocritical care unit between January 2018 and June 2023. The study included fifty consecutive patients with RSE, out of which sixteen adult patients had continuous EEG monitoring both before and during treatment with clobazam until the resolution of RSE. Patients for whom clobazam was the last anti-seizure medication (ASM) used were included in the study. Thirty-four patients were excluded for various reasons, like lack of continuous EEG monitoring (cEEG), status post cardiac arrest, exclusion of clobazam due to medical issues or adverse events, or admission to the hospice floor.
Results
Out of the sixteen patients included in the study, twelve (75%) had focal nonconvulsive RSE on cEEG and four had focal convulsive RSE when clobazam was administered. Thirteen out of sixteen patients (81.25%) responded successfully to clobazam, with an average time of 23.5 hours since starting the medication. On average, three other ASMs were tried before clobazam, initiated at a mean time of 27 hours since SE onset. The study identified EEG patterns correlated with the use of clobazam :1) lateralised periodic discharges that evolved from 1–1.5 Hz to 2–3 Hz, then evolved to rhythmic theta/delta activity with embedded LPDs; 2) repetitive spikes that evolved to theta and delta frequencies (good responders to CLB), and iii) low voltage faster frequencies and evolved to theta delta frequencies (less responders to CLB).
Conclusion
Rapid pharmacoresistance to first-line benzodiazepines and ASM occurs as seizures persist during SE. Our study provides EEG correlates to the successful use of CLB in RSE based on its unique targeting of the GABA-A subtype receptors involved in postsynaptic phasic inhibition.