Early iNO for Oxidative Stress, Vascular Tone and Inflammation in Babies With Hypoxic Respiratory Failure

University of Florida

Overview

The investigators in this study are concerned about the harmful effects of oxygen exposure in newborn infants, particularly at high concentrations. Inhaled nitric oxide (iNO) is an FDA approved drug for the treatment of hypoxic respiratory failure (HRF) in term and late-preterm babies greater than 34 weeks gestation. Hypoxic respiratory failure occurs when a patient's lungs cannot get enough oxygen into their bloodstream. This condition is traditionally treated with high concentrations of oxygen and most often requires the patient be placed on a ventilator (breathing machine). The administration of inhaled nitric oxygen directly into the lungs often improves blood oxygen levels and allows caretakers to reduce the amount of oxygen given to the baby. The purpose of this research study is to evaluate if giving the inhaled nitric oxide earlier in the course of disease improves the effectiveness of the drug, reduces the amount of cellular injury from oxygen exposure, and decreases the total amount of time a patient requires supplemental oxygen. This study uses an FDA approved drug in a new manner.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Conditions

Persistent Fetal Circulation Syndrome Hypertension, Pulmonary, of Newborn, Persistent Persistent Pulmonary Hypertension of Newborn

Eligibility

Sex: ALLMin age: 30 MinutesMax age: 48 Hours

Medical Language ↔ Plain English

Inclusion Criteria: * Gestational age ≥ 35 weeks gestation * Age of life ≤ 48 hours * Diagnosis of hypoxic respiratory failure (HRF) as defined by a post-ductal SaO2 ≤90% in ≥50% oxygen with a PEEP of ≥ 6cm or an oxygenation index (OI) ≥ 10 but ≤ 15 when mean airway pressure and PaO2 are known. * Mothers (ages 18 - 65) of eligible subjects for additional data collection Exclusion Criteria: * Gestational age \< 35 weeks gestation. * Post-natal age \> 48 hours. * Previous treatment with 100% oxygen for longer than 4 hours. * Confirmed congenital diaphragmatic hernia. * Suspected or confirmed congenital airway or pulmonary anomaly. * Suspected or confirmed chromosomal anomaly or genetic aberration, with the exception of patients with trisomy 21 who do not have complex congenital heart disease. * Infants with pneumothorax as the primary cause of their HRF. * Infants with confirmed complex congenital heart disease.

Outcomes

Primary Outcomes

Biomarkers of oxidative injury.

Early administration of iNO to infants with HRF will result in reduced hyperoxia-mediated oxidative injury as measured by known biomarkers of oxygen free radical injury, including malondialdehyde and 8-hydroxy-2'-deoxyguanosine.

Time frame: Urine samples will be collected upon enrollment and then at specific time points within the first 48 hours of study intervention to compare the change in biomarker concentrations from baseline up to hour 48.

Secondary Outcomes

Responsiveness to study treatment.

Earlier administration of iNO to infants with HRF/PPHN (persistent pulmonary hypertension of the newborn) will lessen reactive oxygen species formation resulting in improved responsiveness to the drug as measured by the initial changes in arterial oxygen concentration after administration of the drug.

Time frame: Arterial oxygen concentration will be measured upon enrollment and at specific time points in the first 36 hours of study intervention to compare the change in arterial oxygen concentration from baseline up to hour 36.

Expression of endothelin-1.

Earlier treatment with iNO may potentiate pulmonary vasodilation by modulating endothelin-1 expression.

Time frame: Concentration of endothelin-1 will be measured upon enrollment and at specific time points in the first 36 hours of study intervention to compare the change in concentration from baseline up to hour 36.

Markers of inflammation.

Early iNO may up-regulate production of endogenous anti-inflammatory eicosanoids such as PGE2 (prostaglandin E2). Additionally, avoidance of hyperoxia in these patients may mitigate pro-inflammatory cytokines known to potentiate lung injury.

Time frame: Concentrations of pro and anti-inflammatory markers will be measured upon enrollment and at specific time points in the first 36 hours of study intervention to compare the change in concentrations from baseline up to hour 36.

Duration of oxygen treatment.

Early administration of iNO to infants with HRF will result in at least a 15% reduction in total days of oxygen therapy.

Time frame: Participants will be followed for the duration of their hospital stay, with an expected average stay of 4 weeks.

Expression of VEGF (vascular endothelial growth factor).

Earlier treatment with iNO may potentiate pulmonary vasodilation by preventing hyperoxic down regulation of VEGF.

Time frame: Concentration of VEGF will be measured upon enrollment and at specific time points in the first 36 hours of study intervention to compare the change in concentration from baseline up to hour 36.