Gastric Aspirate Phosphatidylcholine Species in Preterm Neonates Receiving Aerosolized Surfactant.

OBJECTIVE: To characterize phosphatidylcholine (PC) molecular species in serial gastric aspirates as biomarkers for lung maturity, delivery of aerosolized surfactant (AS), and need for intubation. METHODS: In a phase II clinical trial of aerosolized surfactant in preterm neonates with respiratory distress syndrome receiving noninvasive ventilation, infants received a maximum of 2 doses of nebulized beractant. Gastric aspirates were collected before and after each dose and were analyzed for PCs using liquid chromatography mass spectrometry. RESULTS: Of 149 infants enrolled, gastric aspirates were obtained before (n = 91) and after (n = 94) dose 1, and before (n = 56) and after (n = 57) dose 2 of nebulized beractant. The mean ± SD values of birthweight, gestational age, and age at collection of baseline gastric aspirate were 1.7 ± 0.6 kg, 31.7 ± 2.8 weeks, and 5.5 ± 1.7 hours, respectively. The most abundant PC in beractant and gastric aspirates was PC(16:0/16:0). Advancing gestational age and number of antenatal corticosteroid doses predicted increased gastric aspirate PC(16:0/16:0), whereas maternal diabetes predicted a decrease. Several PCs increased significantly (P < .05) after nebulized beractant, consistent with effective aerosol delivery. Infants who received intubation within 72 hours of birth were more likely to have lower PC(16:0/16:0) levels in baseline gastric aspirates compared with those who did not (P = .024). CONCLUSIONS: PC molecular species in gastric aspirates of preterm neonates are potentially novel and precise biomarkers to assess lung maturity, aerosol delivery, and need for endotracheal intubation.

Pulmonary Hypertension Associated with Hypoxic-Ischemic Encephalopathy-Antecedent Characteristics and Comorbidities.

OBJECTIVE: To determine the characteristics of term infants with persistent pulmonary hypertension of the newborn (PPHN) associated with moderate or severe hypoxic ischemic encephalopathy (HIE). METHODS: We compared infants with and without PPHN enrolled in 2 randomized trials of therapeutic hypothermia: the induced hypothermia trial of cooling to 33.5°C for 72 hours vs normothermia, and the "usual-care" arm (33.5°C for 72 hours) of the optimizing cooling trial. RESULTS: Among 303 infants with HIE from these 2 studies, 67 (22%) had PPHN and 236 (78%) did not. We compared infants with PPHN with those without PPHN. The proportion of patients treated with therapeutic hypothermia was similar in PPHN and no-PPHN groups (66% vs 65%). Medication use during resuscitation (58% vs 44%), acidosis after birth (pH: 7.0 ± 0.2 vs 7.1 ± 0.2), severe HIE (43% vs 28%), meconium aspiration syndrome (39% vs 7%), pulmonary hemorrhage (12% vs 3%), culture-positive sepsis (12% vs 3%), systemic hypotension (65% vs 28%), inhaled nitric oxide therapy (64% vs 3%), and extracorporeal membrane oxygenation (12% vs 0%) were more common in the PPHN group. Length of stay (26 ± 21 vs 16 ± 14 days) and mortality (27% vs 16%) were higher in the PPHN group. CONCLUSIONS: PPHN is common among infants with moderate/severe HIE and is associated with severe encephalopathy, lung disease, sepsis, systemic hypotension, and increased mortality. The prevalence of PPHN was not different between those infants receiving therapeutic hypothermia at 33.5°C in these 2 trials (44/197 = 22%) compared with infants receiving normothermia in the induced hypothermia trial (23/106 = 22%).