RESUMO
BACKGROUND: Acute symptomatic epileptic seizures are frequently seen in neurocritical care. To prevent subsequent unprovoked seizures, long-term treatments with antiseizure medications are often initiated although supporting evidence is lacking. This study aimed at prospectively assessing the risk of unprovoked seizure relapse with respect to the use of antiseizure medications. It was hypothesized that after a first acute symptomatic seizure of structural etiology, the cumulative 12-month risk of unprovoked seizure relapse is ≤ 25%. METHODS: Inclusion criteria were age ≥ 18 and acute symptomatic first-ever epileptic seizure; patients with status epilepticus were excluded. Using telephone and mail interviews, participants were followed for 12 months after the acute symptomatic first seizure. Primary endpoint was the occurrence and timing of a first unprovoked seizure relapse. In addition, neuro-intensivists in Germany were interviewed about their antiseizure treatment strategies through an anonymous online survey. RESULTS: Eleven of 122 participants with structural etiology had an unprovoked seizure relapse, resulting in a cumulative 12-month risk of 10.7% (95%CI, 4.7%-16.7%). None of 19 participants with a non-structural etiology had a subsequent unprovoked seizure. Compared to structural etiology alone, combined infectious and structural etiology was independently associated with unprovoked seizure relapse (OR 11.1; 95%CI, 1.8-69.7). Median duration of antiseizure treatment was 3.4 months (IQR 0-9.3). Seven out of 11 participants had their unprovoked seizure relapse while taking antiseizure medication; longer treatment durations were not associated with decreased risk of unprovoked seizure relapse. Following the non-representative online survey, most neuro-intensivists consider 3 months or less of antiseizure medication to be adequate. CONCLUSIONS: Even in case of structural etiology, acute symptomatic seizures bear a low risk of subsequent unprovoked seizures. There is still no evidence favoring long-term treatments with antiseizure medications. Hence, individual constellations with an increased risk of unprovoked seizure relapse should be identified, such as central nervous system infections causing structural brain damage. However, in the absence of high-risk features, antiseizure medications should be discontinued early to avoid overtreatment.
RESUMO
OBJECTIVE: Super-refractory status epilepticus (SRSE) is an enduring or recurring SE after 24 h or more of general anesthesia. This study aimed to evaluate the efficacy and safety of phenobarbital (PB) for the treatment of SRSE. METHODS: This retrospective, multicenter study included neurointensive care unit (NICU) patients with SRSE treated with PB between September 2015 and September 2020 from six participating centers of the Initiative of German NeuroIntensive Trial Engagement (IGNITE) to evaluate the efficacy and safety of PB treatment for SRSE. The primary outcome measure was seizure termination. In addition, we evaluated maximum reached serum levels, treatment duration, and clinical complications using a multivariate generalized linear model. RESULTS: Ninety-one patients were included (45.1% female). Seizure termination was achieved in 54 patients (59.3%). Increasing serum levels of PB were associated with successful seizure control (per µg/mL: adjusted odds ratio [adj.OR] = 1.1, 95% confidence interval [CI] 1.0-1.2, p < .01). The median length of treatment in the NICU was 33.7 [23.2-56.6] days across groups. Clinical complications occurred in 89% (n = 81) of patients and included ICU-acquired infections, hypotension requiring catecholamine therapy, and anaphylactic shock. There was no association between clinical complications and treatment outcome or in-hospital mortality. The overall average modified Rankin scale (mRS) at discharge from the NICU was 5 ± 1. Six patients (6.6%) reached mRS ≤3, of whom five were successfully treated with PB. In-hospital mortality was significantly higher in patients in whom seizure control could not be achieved. SIGNIFICANCE: We observed a high rate in attainment of seizure control in patients treated with PB. Success of treatment correlated with higher dosing and serum levels. However, as one would expect in a cohort of critically ill patients with prolonged NICU treatment, the rate of favorable clinical outcome at discharge from the NICU remained extremely low. Further prospective studies evaluating long-term clinical outcome of PB treatment as well as an earlier use of PB at higher doses would be of value.
