[2006] [3724.3] Oral Sildenafil Treatment as an Alternative to Inhaled NO Therapy for Persistent Pulmonary Hypertension of the Newborn

Jorge Herrea, Roberto Castillo, Elvia Concha, Amed Soliz. Neonatology, Hospital Para El Nio Poblano, Puebla, Mexico; Neonatology, Miami Children's Hospital, Miami, FL.

BACKGROUND: Inhaled nitric oxide (iNO) has been used successfully in infants with severe Persistent Pulmonary Hypertension of the Newborn (PPHN). This therapy is expensive and may not be available in developing countries. Sildenafil,(Viagra®) a type V phosphodiesterase inhibitor (PDI), has been shown to selectively reduce pulmonary vascular resistance in both animal and humans. It is unknown if Sildenafil could be as effective a therapy for PPHN as iNO.
OBJECTIVE: To compare prospectively the efficacy of oral Sildenafil therapy and conventional therapy in term neonates with PPHN in a center without iNO.
DESIGN/METHODS: 24 term neonates with a diagnosis of PPHN and oxygenation index (OI) >25 were randomly assigned to placebo (n=11) or Sildenafil at 2 mg/kg by orogastric tube every 6 h (n=13). Arterial blood gases, OI, mean airway pressure (MAP) and mean blood pressure (BP) were recorded. Clinical management included conventional ventilation, inotropes, but not iNO. Statistical analysis was done by ANOVA, Student's t-test and Fisher exact test.
RESULTS: The changes in OI were significantly lower (p<0.01) in the Sildenafil-treated patients, starting within the first hour after its administration. The PaO2 increased and the change was significant at 72 hours with Sildenafil treatment (p<0.01).MAP was significantly lower in the Sildenafil-treated patients, starting 6 hours after its administration. (p<0.01).No significant differences in PaCO2 or BP were observed.The ventilatory days were significantly lower in the Sildenafil group (p<0.01).
CONCLUSIONS: Oral Sildenafil in term/near term infants with PPHN improves oxygenation indices (OI,PaO2,MAP) without decreasing systemic blood pressure. Further studies are needed to confirm the safety and efficacy of oral Sildenafil.



E-PAS2006:59:3724.3