The Use of Sildenafil in Persistent Pulmonary Hypertension of the Newborn

ABSTRACT

We evaluated the effectiveness of sildenafil in the treatment of neonatal pulmonary hypertension. We performed a double-blind randomized clinical trial in 51 full-term infants with persistent pulmonary hypertension confirmed by Doppler echocardiography. Patients were divided in two groups: 20 infants in group A received placebo when the oxygenation index was >20, and 31 infants in group B received 3 mg/kg of oral sildenafil every 6 hours. Arterial blood gases were taken at 1, 4, 7, 13, 19, and 25 hours after treatment was started. Main outcome measures were oxygenation changes, time on mechanical ventilation, and mortality. Both groups were comparable in general variables as well as in illness severity. We observed better oxygenation parameters after 7 hours of sildenafil treatment, but no significant changes were found in the placebo group. Mortality was higher in the placebo group (40%) than in those infants who received sildenafil (6%; p = 0.004), although no difference was found in time on mechanical ventilation between groups. Our results confirm that sildenafil may be a useful adjuvant therapy for term infants with pulmonary hypertension in centers lacking inhaled nitric oxide and extracorporeal membrane oxygenation.

Neonatal pulmonary hypertension - sildenafil - oxygenation index

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