The relative effectiveness of five antiepileptic drugs in treatment of benzodiazepine-resistant convulsive status epilepticus: a meta-analysis of published studies.

Objective: Systematic evaluation of published evidence-base of the efficacy of five antiepileptic drugs - lacosamide, levetiracetam, valproate, phenytoin and phenobarbital - in convulsive benzodiazepine-resistant status epilepticus.

Methods: Data sources included electronic databases, personal communication, and back tracing of references in pertinent studies. These were prospective and retrospective human studies presenting original data for participants with convulsive benzodiazepine-resistant status epilepticus. Interventions were intravenous lacosamide, levetiracetam, phenobarbital, phenytoin and valproate. Outcome measured is clinically detectable cessation of seizure activity. Level-of-evidence was assessed according to Oxford Centre of Evidence-Based Medicine and The Cochrane Collaboration's Tool for Assessment of Risk. Twenty seven studies (798 cases of convulsive status epilepticus) were identified and 22 included in a meta-analysis. Random-effects analysis of dichotomous outcome of a single group estimate (proportion), with inverse variance weighting, was implemented. Several sources of clinical and methodological heterogeneity were identified.

Results: Efficacy of levetiracetam was 68.5% (95% CI: 56.2-78.7%), phenobarbital 73.6% (95% CI: 58.3-84.8%), phenytoin 50.2% (95% CI: 34.2-66.1%) and valproate 75.7% (95% CI: 63.7-84.8%). Lacosamide studies were excluded from the meta-analysis due to insufficient data.

Conclusions: Valproate, levetiracetam and phenobarbital can all be used as first line therapy in benzodiazepine-resistant status epilepticus. The evidence does not support the first-line use of phenytoin. There is not enough evidence to support the routine use of lacosamide. Randomized controlled trials are urgently needed.