Magnesium therapy in persistent pulmonary hypertension of the newborn: a scoping review.

OBJECTIVE: To map evidence on magnesium sulfate (MgSO₄) therapy for PPHN, focusing on efficacy, safety, mechanisms, and knowledge gaps. STUDY DESIGN: Scoping review following JBI methodology and PRISMA-ScR. MEDLINE, Embase, Cochrane Reviews, and CENTRAL were searched without date restrictions. RESULTS: Thirteen publications were included: 11 primary clinical reports, including three randomized trials, and two evidence syntheses. The primary reports included 253 neonates but differed in populations, severity, comparators, and outcomes. Intravenous MgSO₄ usually comprised a 200 mg/kg loading dose followed by continuous infusion. Small, mostly uncontrolled studies reported improved oxygenation but could not establish efficacy. Comparative studies showed slower or less consistent responses than inhaled nitric oxide or sildenafil. Adverse effects included hypotension, bradycardia, and increased inotropic requirements; long-term safety data were limited. CONCLUSION: Evidence remains insufficient to support routine MgSO₄ use for PPHN.