Pilot Study to Evaluate a New Method for Endotracheal Administration of Surfactant in Neonatal Respiratory Distress Syndrome: Fiberscope Assisted Surfactant Therapy (FAST).

INTRODUCTION: Currently, INSURE (Intubation-Surfactant-Extubation) and LISA (Less Invasive Surfactant Administration) are two recommended techniques for surfactant delivery to newborns with respiratory distress syndrome. The aim of this study was to evaluate the feasibility, safety, tolerability of a new technique of surfactant administration in newborns without anesthesia or laryngoscopy: Fiberscope Assisted Surfactant Therapy (FAST). METHODS: This monocentric, prospective, nonrandomized, pilot feasibility study was conducted from January to December 2021. Spontaneously breathing infants born ≥28 weeks gestational age with respiratory distress syndrome received surfactant by a 1.5 French catheter inserted in the trachea using a flexible endoscope without anesthesia, while maintaining a continuous positive expiratory pressure. The learning curve of this new technique by caregivers was studied during training sessions on high fidelity mannequins. RESULTS: Eight infants born ≥28 weeks of gestation with a birth weight of 1,000 g-2,685 g were included in the study. FAST was successfully performed in each case without anesthesia, second dose of surfactant or mechanical ventilation. One hour after FAST, a decrease of FiO2 and PCO2 and an increase of arterial pressure and pH were recorded with medians of individual differences of -0.9, -4 mm Hg, 6.5 mm Hg, and 0.06, respectively. The learning curves of 13 physicians showed a rapid mastery of FAST from the third attempt onwards (mean duration of 113, 66, and 50 s for 1st, 2nd, and 3rd attempts, respectively, 29-37 s for further attempts). CONCLUSION: FAST may be considered as a possible new minimally invasive surfactant therapy technique for neonates ≥28 weeks with mild respiratory distress syndrome.

Lower Distending Pressure Improves Respiratory Mechanics in Congenital Diaphragmatic Hernia Complicated by Persistent Pulmonary Hypertension.

OBJECTIVE: To investigate the effects of distending pressures on respiratory mechanics and pulmonary circulation in newborn infants with congenital diaphragmatic hernia (CDH) and persistent pulmonary hypertension (PPHN). STUDY DESIGN: In total, 17 consecutive infants of ≥37 weeks of gestational age with CDH and PPHN were included in this prospective, randomized, crossover pilot study. Infants were assigned randomly to receive 2 or 5 cmH2O of positive end-expiratory pressure (PEEP) for 1 hour in a crossover design. The difference between peak inspiratory pressure and PEEP was kept constant. Respiratory mechanics, lung function, and hemodynamic variables assessed by Doppler echocardiography were measured after each study period. RESULTS: At 2 cmH2O of PEEP, tidal volume and minute ventilation were greater (P < .05), and respiratory system compliance was 30% greater (P < .05) than at 5 cmH2O. PaCO2 and ventilation index were lower at 2 cmH2O than at 5 cmH2O (P < .05). Although preductal peripheral oxygen saturation was similar at both PEEP levels, postductal peripheral oxygen saturation was lower (median [range]: 81% [65-95] vs 91% [71-100]) and fraction of inspired oxygen was greater (35% [21-70] vs 25% [21-60]) at 5 cmH2O. End-diastolic left ventricle diameter, left atrium/aortic root ratio, and pulmonary blood flow velocities in the left pulmonary artery were lower at 5 cmH2O. CONCLUSIONS: After surgical repair, lower distending pressures result in better respiratory mechanics in infants with mild-to-moderate CDH. We speculate that hypoplastic lungs in CDH are prone to overdistension, with poor tolerance to elevation of distending pressure.