Jul 2026· Journal of Neurology Neurosurgery & Psychiatry· Vol 97, pp. 899 - 907· 1 citation· 27 references
Medicine
TL;DR
Improved timely EEG access, including weekends, may be a modifiable system-level target to improve SE outcomes, as prolonged waiting times for EEG for the diagnosis of SE were associated with worse neurological outcomes at discharge and higher mortality.
Abstract
Background Status epilepticus (SE) is associated with substantial mortality and morbidity that increase with seizure duration. Prompt diagnosis is essential, but access to electroencephalography (EEG) is often limited outside regular working hours. We examined whether EEG delay due to prolonged waiting times for EEG is associated with worse outcomes. Methods This retrospective cohort study comprised adults (≥18 years; n=163) with first-time, non-anoxic, EEG-verified non-convulsive SE treated at Odense University Hospital, Denmark (2008–2017). EEG delay was defined as the time from last antiseizure treatment or clinical suspicion of SE to EEG confirmation. Outcomes were new neurological deficit at discharge and 2-year all-cause mortality. External validation used two retrospective German cohorts (n=906) differing in weekend EEG availability. Results Median EEG delay was 11.7 hours (IQR 3.5–22.6) and correlated with SE duration (r=0.2, p<0.01). Longer delay was associated with new neurological deficits at discharge (p<0.001 across delay groups; ρ=0.152, p=0.03) and higher long-term mortality (log-rank p=0.007), driven mainly by delays>22.6 hours. Multivariable analyses for 1 year mortality adjusting for factors including aetiology and age supported an independent association between delay and higher mortality. Delays were longer for Friday/Saturday admissions when next-day EEG was unavailable, with lower survival. In validation, lack of weekend EEG access showed etiology-dependent weekend-weekday mortality differences (eg, +18.8% in remote symptomatic SE; p=0.01) not seen in centres with weekend EEG availability. Conclusion In this cohort, prolonged waiting times for EEG for the diagnosis of SE were associated with worse neurological outcomes at discharge and higher mortality. Improving timely EEG access, including weekends, may be a modifiable system-level target to improve SE outcomes.
BackgroundTo evaluate the use, diagnostic yield, and timing of EEG in emergency department (ED) patients receiving second-line intravenous antiseizure medication (IV ASM).MethodsWe retrospectively reviewed patients aged ≥16 years who received IV ASM at Tampere University Hospital over one year. Episodes were categorized by status epilepticus (SE) subtype and arrival time (office vs off-hours). Timing of ASM/EEG and EEG's diagnostic contribution were analyzed.ResultsWe identified 132 episodes in 116 patients (41% female; median age 66 years). Convulsive SE (CSE) was most common (n = 41), followed by nonconvulsive SE (NCSE, n = 21), comatose SE (n = 10), and focal aware SE (FASE, n = 8). Recurrent seizures (n = 32) and postictal states (n = 20) were also included to highlight diagnostic challenges. Median IV ASM timing was 55 min post-ED arrival. EEG was substantially delayed (median 13 h 34 min). 70% arrived off-hours, when EEGs were performed less frequently (63% vs 87%; p = 0.006) and later (16 h 12 min vs 2 h 41 min; p < 0.001). In 94% of off-hours cases, ASM was given before EEG. EEG was diagnostic in 86% NCSE and 80% comatose SE cases. Post-treatment, EEG revealed ongoing SE in 39% overall (15% CSE).ConclusionsEEG is essential for diagnosing NCSE and comatose SE and for assessing treatment response in all SE types. However, marked delays, particularly during off-hours, limit its clinical utility. Improving rapid EEG access in ED may enhance diagnostic accuracy and guide timely therapeutic decisions.
Teemu Pöytäkangas, P. Basnyat, J. Saarinen et al.· Clinical EEG and Neuroscienc...· 0 citations
BACKGROUND
Convulsive status epilepticus (CSE) is a time-sensitive neurological emergency in which delayed treatment may contribute to pharmacoresistance and poor outcomes. Evidence comparing third-line antiseizure medications in children remains limited. Objective To compare intravenous lacosamide and phenytoin in pediatric refractory CSE and to determine whether treatment timing predicts seizure cessation. Methods This prospective observational cohort study included 100 children aged 1 month-16 years with refractory CSE treated with intravenous lacosamide (n = 46) or phenytoin (n = 54) after failure of benzodiazepines and levetiracetam. The primary objective was to evaluate the effect of treatment delay on seizure cessation. Secondary outcomes included treatment response, electroencephalographic findings, cardiac safety, and predictors of treatment failure. Results Seizure cessation was achieved in 56% of patients and did not differ significantly between lacosamide and phenytoin (60.9% vs. 51.9%, p = 0.365). Treatment delay was the strongest independent predictor of failure; each additional hour from seizure onset to treatment initiation increased the odds of failure by 11% (adjusted OR 1.11, 95% CI 1.03-1.19; p = 0.005). Greater baseline antiseizure medication burden was also independently associated with treatment failure (adjusted OR 2.10, 95% CI 1.05-4.17; p = 0.035). Persistent epileptiform activity on 24-hour EEG was significantly associated with poor outcome (p < 0.001). Both medications were well tolerated. Conclusions Lacosamide and phenytoin demonstrated comparable efficacy and safety. Treatment timing, rather than drug selection, was the principal determinant of seizure cessation, emphasizing the importance of rapid escalation of therapy in pediatric refractory CSE.
Michael Nabil Halim, Rasha Hussein Aly Hussein, O. El-Rashidy et al.· Epilepsy & Behavior· 0 citations
BACKGROUND
Point-of-care electroencephalography (pocEEG) may help distinguish nonconvulsive status epilepticus from postictal or nonepileptic altered mental status in children. However, its real-world clinical use is not well described.
METHODS
This single-center retrospective cohort study screened ED visits at a tertiary pediatric emergency department between August 1, 2024, and July 31, 2025. Children aged <18 years presenting with seizure or altered mental status were included if they had ongoing seizure activity, impaired consciousness, reduced responsiveness, or persistent postictal altered mental status on arrival. Factors associated with pocEEG use were evaluated using Firth-penalized multivariable logistic regression.
RESULTS
Among 163 included children, 72 (44%) underwent pocEEG. Univariable analyses showed associations between pocEEG use and prolonged seizures, ongoing seizure on arrival, reduced Glasgow Coma Scale (GCS) eye-opening response on arrival, history of intracranial disease, and longer seizure duration. In the primary five-variable multivariable model, pocEEG use was independently associated with seizures lasting ≥15 min (adjusted odds ratio [aOR]: 2.95, 95% confidence interval [CI]: 1.48-5.96) and reduced GCS eye-opening response on arrival (aOR: 3.35, 95% CI: 1.60-7.28). Children who underwent pocEEG more frequently received midazolam and phenobarbital and were more often admitted to the pediatric intensive care unit. Nonconvulsive status epilepticus was classified in 10 of 72 monitored children.
CONCLUSIONS
pocEEG was preferentially used in children with prolonged seizures and reduced GCS eye-opening response on arrival. These findings describe current clinical selection for pocEEG and support prospective studies assessing how pocEEG influences antiseizure medication decisions.
Tsuyoshi Aihara, S. Amagasa, Tatsuya Takahashi et al.· American Journal of Emergenc...· 0 citations
Nonconvulsive status epilepticus (NCSE) is difficult to recognize in the emergency department (ED), where onset is often unknown and treatment may be delayed. To what extent treatment timing and dose adequacy are associated with outcome in NCSE remains debated. In this single-center electroencephalography (EEG)-based study, adults with NCSE diagnosed in the ED were included. Timing was measured using ED arrival as a temporal anchor. Outcomes were failure to return to baseline at discharge and in-hospital mortality. Among 74 patients (mean age 66.8), 38 (51.4%) failed to return to baseline and 14 (18.9%) died. ED benzodiazepines (BDZs) were administered in 43 patients (58.1%) and anti-seizure medications (ASMs) in 71 (95.9%). Median times to BDZ and ASM administration were 184 and 223 min, respectively. After adjustment for Status Epilepticus Severity Score (STESS), potentially fatal etiology, and premorbid modified Rankin Scale score, time to ASM (odds ratio [OR]: 1.11 per hour; 95% confidence interval [CI]: 1.01-1.22; p = .037) and ASM underdosing (OR: 3.43; 95% CI: 1.10-10.68; p = .034) were independently associated with failure to return to baseline, with time to BDZ showing a non-significant trend. BDZ underdosing was not associated with functional outcome, and no treatment variable was associated with mortality. These findings support early EEG-based recognition and rapid, adequately dosed ASM treatment as key targets in ED-NCSE management.
Francesco Misirocchi, Alice Ballabeni, Maddalena Frapporti et al.· Epilepsia· 0 citations
Objective: The EEG (electroencephalogram) plays a crucial role in prognosticating outcomes for comatose patients after cardiac arrest (CA), but the precise probability of poor outcome (PPO) associated with specific EEG patterns and how it changes over time is not well understood. We aimed to quantify the PPO for individual EEG patterns, assess its precision, and evaluate time-dependent changes after CA. Methods: We retrospectively analyzed continuous EEGs from comatose adults treated at three Boston hospitals for CA (2010–2023). We evaluated the prognostic significance of 22 ACNS-standard patterns, and one additional pattern, “flat EEG (<2μV)”, using PPO (i.e., positive predictive value for poor outcome) with 95 % Wilson confidence intervals as the primary metric; sensitivity, and false-positive rate (FPR) were secondary. Temporal variabilities were assessed in four epochs (0–24, 24–48, 48–72, >72 h) using linear regression. Poor and favorable outcomes were defined as death and survival to discharge, respectively. Results: Among 1,000 patients, the mean age was 58 years for survivors and 60 years for non-survivors; 59% of patients were male. Flat EEG demonstrated PPO of 1.00 across epochs, but CIs ranged from 0.89–1.00 at 24 hours and widened to 0.54–1.00 beyond 72 hours. Status epilepticus (SE) showed PPO of 0.80 (0.44–0.97) at 24 hours, 1.00 (0.74–1.00) at 48 hours, and 0.67 (0.09–0.99) after 72 hours. Suppression (< 10 μV), the most common historically termed highly “malignant” pattern (prevalence 50–65%), had a PPO of 0.76–0.83 and sensitivity of up to 0.80, with 17–24% of patients experiencing a favorable outcome. Time-dependent analysis further demonstrated that PPO for suppression increased over time, while sensitivity declined for burst-suppression and flat EEG. Conclusion: The prognostic uncertainty of EEG patterns post-CA is highly variable, and evolves within the first 72 hours. Flat EEG, and SE are highly specific prognosticators of poor outcome, but, importantly, they are rare and not infallible. Suppression identifies the most patients with poor outcomes but has moderately high FPRs and variable prognostic certainty over time. Future large-scale prospective studies that incorporate long-term outcomes are needed to validate these findings.
Rajib Kanti Dey, A. Yaramış, Niels Turley et al.· Neurology open access· 0 citations
PURPOSE
To evaluate clinical determinants of refractoriness and outcome in status epilepticus (SE) in a prospective low- and middle-income country (LMIC) cohort.
METHODS
In this single-centre prospective cohort study, 97 consecutive SE patients were classified as non-refractory status (NRSE, n = 50), refractory (RSE, n = 31), or super-refractory SE (SRSE, n = 16). A single 21 channel video-EEG was done within 24 h of presentation to the hospital. Clinical context, preexisting epilepsy history, etiology, Status Epilepticus Severity Score (STESS) and EEG findings were recorded, and outcome was assessed through in-hospital mortality.
RESULTS
The median age of our cohort was 32 years; most common etiologies were remote symptomatic (68%), acute symptomatic (19%) and progressive symptomatic (5%). Patients with drug-sensitive epilepsy (DSE) showed low refractoriness and mortality (29%, 6%), whereas drug-resistant epilepsy and new-onset status epilepticus (NOSE) were more likely to be refractory (68% and 70% respectively) and had higher mortality (26% and 30% respectively). Overall mortality was 16.5%, increasing stepwise from 4% (NRSE) to 13% (RSE) to 63% (SRSE; p < 0.001). STESS discriminated between non-survivors and survivors (median 3 vs 0; p < 0.001). Among 85 patients with available EEG, periodic discharges (PDs) were associated with 71% mortality (p < 0.001).
CONCLUSION
Status Epilepticus in the setting of DSE carries a favourable prognosis, while DRE and NOSE confer refractoriness. A short-term early EEG performed in the first 24 h is associated with refractoriness and its exact role warrants further studies.
S. Lodha, Babu Rao Challepalle, Shubho Acharya et al.· Epilepsy & Behavior· 0 citations
We use cookies to run the site and, with your consent, for analytics and to show ads.
See our Cookie Policy.
