Inhaled Nitric Oxide (iNO) is a drug approved by the Food and Drug Administration that is commonly used in term and near-term neonates who have severe respiratory failure caused by pulmonary hypertension. Over the last decade there have been multiple large studies trying to determine a clinical use for iNO in preterm neonates, but despite evidence of short-term benefit, this drug has not been shown to improve long-term outcomes in preemies. Still, the drug is commonly being used in this population, experts say.