Inhaled PGE1 in Neonatal Hypoxemic Respiratory Failure

This pilot study was a randomized, placebo-controlled, clinical trial to test the safety of using the intravenous form of Prostaglandin E1 (PGE1) in an inhaled form for treatment of hypoxemic respiratory failure in term newborns. The study planned to enroll 50 infants diagnosed with hypoxemic respiratory failure at nine NICHD Neonatal Research Network sites, and randomly assign them to receive one dose over a 72-hour period of either high concentration PGE1 (300 ng/kg/min), low concentration PGE1 (150 ng/kg/min), or placebo (normal saline, the diluent for the drug). In addition to determining the safety, optimal dose, and duration of the therapy, this pilot trial planned to evaluate the feasibility of conducting a larger, multi-center randomized, blinded placebo-controlled trial.

Hypoxemic respiratory failure (HRF), frequently associated with persistent pulmonary hypertension of the newborn (PPHN), is a rare, but life-threatening condition affecting approximately 2 to 9 percent of infants admitted to neonatal intensive care units and results in significant morbidity and mortality. It occurs more often in full- or post-term babies whose circulatory systems do not adapt well to breathing outside the womb. HRF may result from congenital hernia of the diaphragm, group B streptococcal infection, inhaling meconium in the womb, or respiratory distress syndrome.

Medical treatments, such as high frequency ventilation, inhaled nitric oxide, and Extracorporeal Membrane Oxygenation (ECMO, a heart and lung support machine), have significantly increased survival of children with HRF. These therapies, while successful, however, have a variety of side effects and potential long-term disabilities.

This feasibility trial was designed to test the safety of using the intravenous form of Prostaglandin E1 in an inhaled form (iPGE1) on infants born at 34 0/7ths weeks gestational age or greater diagnosed with hypoxemic respiratory failure and on assisted ventilation. The intravenous form of PGE1 was to be aerosolized and administered via a nebulizer attached to the infant's ventilator. The goal was to enroll 50 subjects within 6-9 months, in preparation for a larger, multi-center randomized control trial; however, the study was withdrawn for lack of recruitment.

Eligibility Criteria:
Inclusion Criteria:

* Infants born at 34 0/7ths weeks gestational age or greater (by best obstetrical estimate) and at a postnatal age no greater than 7 days (168 hours)
* Infants diagnosed with hypoxemic respiratory failure (HRF), including perinatal aspiration syndrome (meconium, blood, or amniotic fluid), pneumonia/ sepsis, respiratory distress syndrome, or idiopathic respiratory failure
* Infants who will receive assisted ventilation for HRF
* Infants with an oxygenation index (MAP x FiO2 x 100/PaO2)(OI) of 15-25 on two arterial gases taken between 15 minutes and 12 hours apart
* An indwelling arterial line
* Infants whose parents/legal guardians have provided consent for enrollment

Exclusion Criteria:

* Any infant in whom a decision has been made not to provide full treatment
* Known structural congenital heart disease, except patent ductus arteriosus and atrial/ventricular level shunts
* Congenital diaphragmatic hernia
* Preterm neonates less than 34 weeks
* Thrombocytopenia (platelet count \< 80,000/μl) unresponsive to platelet transfusion
* Infants receiving hypothermia for hypoxic ischemic encephalopathy
* Previous treatment with inhaled nitric oxide
* Infants already enrolled in a conflicting and/or Investigational New Drug (IND) clinical trial
* Infants whose parents/legal guardians refuse consent