Objective: To determine the effect of adenosine for the management of persistent pulmonary hypertension of the newborn.
Design: Prospective, observational case series report.
Setting: A single, tertiary referral neonatal intensive care unit.
Patients: Nine neonates with persistent pulmonary hypertension of the newborn requiring mechanical ventilation and inhaled nitric oxide at 20 parts per million.
Interventions: A continuous intravenous infusion of adenosine at 50 microg/kg/min.
Measurements and main results: Peripheral arterial oxygen saturation, arterial oxygen tension, invasive systemic arterial blood pressure, and pulmonary arterial pressure, estimated using echocardiography, were recorded. There was a significant improvement in arterial oxygenation tension in six of nine neonates who responded to adenosine: PaO2 increased from 66.8 (range, 47-70.5) torr (8.8 kPa) to 73.5 (range, 58.5-94.2) (p=.02) and pulmonary arterial pressure decreased significantly from 63 (range, 42.5-64.0) to 43.5 (range, 32.75-49) mm Hg (p=.002). The pulmonary to systemic mean artery pressure ratio fell from 1.27 (range, 0.88-1.5) to 0.81 (range, 0.64-0.84) (p=.002). Three neonates did not respond to adenosine infusion.
Conclusions: The use of adenosine infusion in combination with inhaled nitric oxide may be a potentially valuable therapeutic option for the treatment of pulmonary hypertension of the newborn. Neonates with irreversible lung pathology may not respond to adenosine infusion.