Rationale:
Refractory Status Epilepticus (RSE) is a life-threatening condition often resistant to conventional antiseizure medications. Magnesium, an NMDA receptor antagonist, has been suggested as a potential therapeutic option for non-eclamptic RSE, particularly in cases unresponsive to other treatments. This study aimed to evaluate the effectiveness of magnesium treatment in RSE patients by analyzing EEG changes and identifying clinical characteristics predictive of response.
Methods:
A retrospective analysis was conducted on RSE patients treated with magnesium at Ajou University Hospital between January 2015 and December 2022. The magnesium infusion protocol included an initial 4g bolus over 15 minutes, followed by maintenance infusion at 1-2g/hr, targeting a serum magnesium level of 8.5 mg/dL. All patients underwent continuous video EEG monitoring, and the exact time of the first magnesium bolus (4g) administration was recorded to the minute. EEG power in delta, theta, alpha, and beta frequency bands was analyzed by comparing the 1-hour window before and the 1-hour window after magnesium administration. Responders were defined as those showing a reduction in delta band power after magnesium administration.
Results:
A total of 25 patients received magnesium treatment, and 15 had sufficient EEG data for analysis. Among these, 53.3% (n=8) were classified as responders, demonstrating a significant reduction in delta band power within 1 hour post-administration. In the responder group, pre-treatment EEG characteristics showed relatively higher power in the alpha and beta bands. Two patients discontinued magnesium therapy due to complications, specifically bradyarrhythmia. Other clinical characteristics, such as age, sex distribution, premorbid mRS, RSE etiology, STESS scores, were similar between responders and non-responders. Two patients discontinued magnesium treatment due to the development of bradyarrhythmia.
Conclusions:
Magnesium shows promise as a treatment option for RSE, with approximately half of the patients demonstrating a significant reduction in delta band power within 1 hour of administration. Pre-treatment EEG characteristics, specifically higher alpha and beta power, may help identify likely responders. Further studies are warranted to confirm these findings and optimize patient selection for magnesium therapy in RSE.
Funding: No specific funding was reported for this study.