Which condition in term and near term neonates should have a trial of inhaled nitric oxide?

• A. Pneumonia
• B. Meconium aspiration
• C. Pulmonary edema
• D. Hypoxic respiratory failure

Answer: (D)

Inhaled nitric oxide is used in term and near-term neonates when hypoxemic respiratory failure is driven by persistent pulmonary hypertension of the newborn. It acts as a selective pulmonary vasodilator, lowering pulmonary vascular resistance and reducing right-to-left shunting across the foramen ovale and ductus arteriosus, which improves arterial oxygenation. This makes it the best choice for a neonate whose hypoxemia stems from PPHN. It’s not a general treatment for pneumonia or pulmonary edema, where the focus is on treating the underlying infection or fluid/volume issues rather than addressing elevated pulmonary vascular resistance. Meconium aspiration can lead to PPHN, so iNO may help if PPHN is present, but the critical factor is the presence of high PVR causing hypoxic respiratory failure.