[Efficacy of magnesium in a case of neonatal pulmonary hypertension refractory to the usual therapies].

We describe a premature baby with X pentasomy, having a severe pulmonary hypertension secondary to perinatal asphyxia and hyaline membrane disease which appeared to be refractory to conventional treatments (hyperventilation, tolazoline, prostacyclin). Oxygenation and pulmonary hypertension rapidly improved after starting magnesium sulphate infusion (loading dose: 20 mg/kg e.v. of elementary Mg, followed by continuous infusion of 2-4 mg/kg/hr during 6 days). The therapy was associated with hypermagnesemia (5-7 mg/100 ml) and transitory side effects (hypocalcemia, muscular and bladder paresis, bradycardia without hemodynamic decompensation). We suggest that magnesium therapy might be considered in newborns with severe and persistent pulmonary hypertension.