Evaluation of Postnatal Magnesium Sulfate Therapy on Neurological Outcomes of Term Neonates with Birth Asphyxia Admitted in a Tertiary Care Hospital

Abstract

Background: Perinatal asphyxia continues to drive a disproportionate share of preventable newborn deaths and lifelong neurological morbidity across the Indian subcontinent. Magnesium, a physiological blocker of the NMDA-type glutamate receptor, has biological grounds for limiting secondary neuronal injury after a hypoxic insult.

Objective: We sought to quantify the impact of an early postnatal magnesium sulfate regimen on neurological recovery, seizure burden, and discharge readiness in asphyxiated term newborns managed at a north-east Indian referral unit.

Methods: A parallel-arm, allocation-concealed and double-masked trial was undertaken in the level-III neonatal unit of a referral hospital in southern Assam. One hundred and twenty term newborns with intrapartum asphyxia were assigned 1:1 to either three deep intramuscular doses of 50 % magnesium sulfate (250 mg/kg per administration, spaced one day apart) or volume-matched saline through the same route. The pre-specified primary endpoint was the neurological examination at the time of nursery discharge. Pre-planned secondary endpoints captured convulsion frequency and recurrence, time to first enteral feed, cranial sonographic abnormalities, length of admission, and in-hospital death.

Results: The two arms were well matched at enrolment. By the time of nursery discharge, an unremarkable neurological examination was documented in 71.7 % of magnesium recipients against 51.7 % of controls (p = 0.03). Convulsions recurring three or more times affected 13.3 % versus 48.3 % (p < 0.001); the mean count of seizure episodes per neonate fell from 3.92 ± 2.11 in the saline arm to 1.43 ± 1.58 in the intervention arm (p < 0.001). Enteral feeds were tolerated by day two in 96.7 % of the magnesium group, compared with 81.7 % of controls (p = 0.01), and the length of admission was less than half — 3.10 ± 1.05 days against 5.48 ± 1.62 days (p < 0.001). Sonographic markers of hypoxic injury were also considerably less prevalent under magnesium (26.7 % versus 48.3 %; p = 0.02). Death before discharge trended lower in the intervention arm (3.3 % versus 10.0 %) without reaching the conventional threshold of significance (p = 0.17).

Conclusion: An early postnatal course of intramuscular magnesium sulfate yielded measurable gains in early neurological recovery and a substantial fall in seizure recurrence among asphyxiated term newborns. Confirmation in adequately powered multi-site investigations with neurodevelopmental endpoints at 18–24 months is the logical next step.