Noninvasive Neurally Adjusted Ventilation in Postextubation Stabilization of Preterm Infants: A Randomized Controlled Study.

OBJECTIVE: To compare the effects of noninvasive neurally adjusted ventilatory assist (NIV-NAVA) to nasal continuous positive airway pressure (NCPAP) in achieving successful extubation in preterm infants. STUDY DESIGN: This prospective, single-center, randomized controlled trial enrolled preterm infants born at <30 weeks of gestation who received invasive ventilation. Participants were assigned at random to either NIV-NAVA or NCPAP after their first extubation from invasive ventilation. The primary outcome of the study was extubation failure within 72 hours of extubation. Electrical activity of the diaphragm (Edi) values were collected before extubation and at 1, 4, 12, and 24 hours after extubation. RESULTS: A total of 78 infants were enrolled, including 35 infants in the NIV-NAVA group and 35 infants in the NCPAP group. Extubation failure within 72 hours of extubation was higher in the NCPAP group than in the NIV-NAVA group (28.6% vs 8.6%; P = .031). The duration of respiratory support and incidence of severe bronchopulmonary dysplasia were similar in the 2 groups. Peak and swing Edi values were comparable before and at 1 hour after extubation, but values at 4, 12, and 24 hours after extubation were lower in the NIV-NAVA group compared with the NCPAP group. CONCLUSIONS: In the present trial, NIV-NAVA was more effective than NCPAP in preventing extubation failure in preterm infants. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02590757.

Pulmonary Arterial Hypertension after Ibuprofen Treatment for Patent Ductus Arteriosus in Very Low Birth Weight Infants.

OBJECTIVE: To describe the clinical course and risk factors for pulmonary arterial hypertension (PAH) after ibuprofen treatment to close patent ductus arteriosus. STUDY DESIGN: All neonates weighing < 1500 g at birth who received ibuprofen to close patent ductus arteriosus and were admitted to Seoul National University Children's Hospital's neonatal intensive care unit in 2010-2014 were eligible for this study. The study population was divided into the PAH and non-PAH groups, and medical records were retrospectively reviewed. RESULTS: Of the 144 eligible infants, 10 developed PAH (6.9%). Relative to the non-PAH group, the PAH group exhibited greater respiratory severity and more frequent severe bronchopulmonary dysplasia or death before 36 weeks postmenstrual age. Multivariable analysis demonstrated that lower gestational age, birth weight in less than the third percentile for age, maternal hypertension of pregnancy, and oligohydramnios were risk factors for developing PAH after ibuprofen treatment. CONCLUSION: A high incidence of PAH after ibuprofen treatment was observed in the study population. Furthermore, younger gestational age and several prenatal conditions were identified as risk factors for developing PAH after ibuprofen treatment. Additional large cohort studies are necessary to confirm our results.

Randomized crossover study of neurally adjusted ventilatory assist in preterm infants.

OBJECTIVE: To determine whether neurally adjusted ventilatory assist (NAVA), a new method of mechanical ventilation that delivers pressure assistance that is proportional to the electrical activity of the diaphragm (EAdi), could lower the inspiratory pressure and respiratory muscle load in preterm infants supported with ventilators. STUDY DESIGN: Twenty-six mechanically ventilated preterm infants were randomized to crossover ventilation with NAVA and synchronized intermittent mandatory ventilation (SIMV) with pressure support (PS) for 4 hours each in a randomized order. A 1-hour interval for washout was provided between the 2 modes of ventilation. The ventilator settings were adjusted to maintain similar levels of end-tidal partial pressure of CO(2). The ventilator parameters, vital signs, and gas exchange effects under the 2 ventilatory modes were compared. RESULTS: Nineteen infants completed the 9-hour crossover comparison protocol. Peak inspiratory pressure (PIP), work of breathing, and peak EAdi with NAVA were lower than those in SIMV with PS. Calculated tidal volume to peak EAdi ratio and PIP to peak EAdi ratio were higher with NAVA. There were no significant differences in mean airway pressure, inspiratory oxygen fraction, and blood gas values. The measurements of vital signs did not differ significantly between the 2 modes. CONCLUSION: NAVA lowered PIP and reduced respiratory muscle load in preterm infants at equivalent inspiratory oxygen fraction and partial pressure of CO(2) of capillary blood in comparison with SIMV with PS.

Intrauterine inflammation as a risk factor for persistent ductus arteriosus patency after cyclooxygenase inhibition in extremely low birth weight infants.

OBJECTIVES: To test the hypothesis that intrauterine inflammation increases prostaglandin production and may be a risk factor for persistent ductus arteriosus after therapy with indomethacin, a nonselective cyclooxygenase inhibitor. STUDY DESIGN: Indomethacin therapy was started after confirming ductus arteriosus within 24 hours after birth in extremely low birth weight infants. After one cycle of therapy, infants with closed ductus were classified as responders, and those with patent ductus were classified as nonresponders. Multiple logistic regression analysis was used to determine important perinatal factors associated with persistent ductus arteriosus. Immunohistochemistry with cyclooxygenase antibodies and radioimmunoassay by 6-keto prostaglandin F(1α) kit were used to determine the relationship between intrauterine inflammation and ductal patency. RESULTS: Forty-one infants were responders, and 37 infants were nonresponders. Responders were frequently small for gestational age; nonresponders frequently had lower gestational age, respiratory distress syndrome, and intrauterine inflammation. By multiple logistic regression analysis, respiratory distress syndrome and intrauterine inflammation were more frequent in nonresponders. Cyclooxygenase-1 expression in the umbilical arteries and plasma 6-keto prostaglandin F(1α) levels were higher in nonresponders. CONCLUSIONS: Respiratory distress syndrome and intrauterine inflammation were independent risk factors for persistent ductus arteriosus after indomethacin therapy in extremely low-birth weight infants. Intrauterine inflammation may have a negative influence on ductus arteriosus closure via increased cyclooxygenase-1 activity.