Effect of postnatal magnesium therapy on neonatal seizure in infants with moderate to severe hypoxic ischemic encephalopathy: a post- hoc subgroup analysis

Abstract

Background: Magnesium has got both neuroprotective and anticonvulsant effect on developing human brain. A post hoc subgroup analysis was done to determine the effect of magnesium on neonatal seizures in infants with moderate-severe hypoxic ischemic encephalopathy (HIE) who received postnatal magnesium therapy for perinatal asphyxia. Methods: Term asphyxiated infants were randomly assigned to receive either magnesium sulphate infusion or placebo within 48 hours of life to maintain serum magnesium levels in neuroprotective range. Short term neurological outcome at discharge was evaluated. The post hoc analysis evaluated the effect of magnesium on neonatal seizures in infants with moderate-severe HIE. All statistical analysis was done through SPSS (version 19.0) for windows and p value <0.05 was taken as statistically significant. Results: Sixty infants were included in magnesium and 60 in placebo group. Both groups were similar in baseline characteristics. Of 36 infants in magnesium group with moderate to severe HIE, 25 (69%) had neonatal seizures vs 27 (82%) of 33 infants in placebo group (p value 0.23). Among those with seizures, seizure control was achieved with single anticonvulsant in 24 infants (96%) in magnesium group vs 20 (74%) in placebo (p value 0.02). Seizures got controlled early in magnesium group compared to placebo, 36.5 hours vs 55 hours (p value 0.02). At discharge, anticonvulsant was required for 2 infants in magnesium group and 3 in placebo group. Conclusions: Postnatal magnesium therapy as a neuroprotective agent in moderate-severe HIE may decrease the duration of clinical seizures and need for multiple anticonvulsants during the critical period of neuronal damage.