Pathophysiologic principles relevant for therapeutic procedures in persistent pulmonary hypertension of the newborn.

Though the various pathophysiologic mechanisms underlying persistent pulmonary hypertension of the newborn (PPHN) necessitate rather specific therapeutic concepts, in the majority of infants with PPHN management is mainly focused on the treatment of the symptoms respiratory failure and cardiovascular abnormalities. For the few neonates with severe PPHN who fail to respond to optimized conventional ventilatory support, high-frequency oscillatory ventilation and extracorporeal membrane oxygenation are available. Treatment of cardiovascular abnormalities should be based on knowledge of the pathophysiologic events in the heart and in the pulmonary and systemic circulation of the newborn with PPHN at least as far as these events are known or suspected based on animals studies. The primary goals of therapy in PPHN must be reduction of right ventricular afterload and support of myocardial function. In this context inhalational nitric oxide therapy may be effective as a new therapeutic strategy to decrease pulmonary vascular resistance.