Electro-clinical efficacy and safety of midazolam in neonatal seizures: a systematic review with individual level exploratory analysis of gestational age-related treatment response.

Neonatal seizures are the most common neurological emergency during the neonatal period and are associated with increased mortality and adverse neurodevelopmental outcomes. Despite current recommendations supporting phenobarbital as first-line therapy, seizure control remains suboptimal in a large proportion of neonates, prompting the use of second-line antiseizure medications. Midazolam is increasingly administered in refractory neonatal seizures but evidence regarding its electro-clinical efficacy and safety remains limited and heterogeneous. To systematically review the available evidence on the electro-clinical efficacy and safety of midazolam in neonatal seizures and to perform an exploratory individual-level analysis investigating the association between gestational age and treatment response. A systematic review was conducted according to PRISMA 2020 guidelines. Studies including neonates with EEG- or aEEG-confirmed seizures treated with midazolam were included. Binary logistic regression was performed to assess the individual-level association between gestational age and treatment response. Eleven studies involving 146 neonates treated with midazolam were included. Electro-clinical response was observed in 101/146 neonates (69.2%), while seizure cessation was achieved in 61/146 neonates (41.8%). In an exploratory complete-case logistic regression analysis, higher gestational age appeared to be associated with a greater probability of electro-clinical response. The predicted probability curve crossed the 50% response probability at approximately 36.5 weeks of gestation. Hypotension was the most frequently reported adverse event, while respiratory depression, sedation-related effects, and transient EEG/aEEG suppression were reported less frequently.

conclusionsMidazolam may have a role as an add-on antiseizure medication in neonatal seizures, particularly in refractory cases. However, the evidence remains limited by heterogeneity in study design, EEG monitoring strategies, outcome definitions, and incomplete individual-level data. The observed association between gestational age and response is hypothesis-generating and requires prospective validation. WHAT IS KNOWN: • Phenobarbital often provides incomplete seizure control in neonates, making second-line antiseizure therapies necessary in refractory cases. • Evidence supporting midazolam for neonatal seizures remains limited and heterogeneous. WHAT IS NEW: • This systematic review summarizes the electro-clinical efficacy and safety of midazolam and includes an exploratory patient-level analysis suggesting that higher gestational age may be associated with improved treatment response. • These findings support further prospective studies on developmental determinants of response to GABAergic therapy.