A Multicenter Lung Ultrasound Study on Transient Tachypnea of the Neonate

Background and Aim: Discordant results that demand clarification have been published on diagnostic lung ultrasound (LUS) signs of transient tachypnea of the neonate (TTN) in previous cross-sectional, single-center studies. This work was conducted to correlate clinical and imaging data in a longitudinal and multicenter fashion. Methods: Neonates with a gestational age of 34-40 weeks and presenting with TTN underwent a first LUS scan at 60-180 min of life. LUS scans were repeated every 6-12 h if signs of respiratory distress persisted. Images were qualitatively described and a LUS aeration score was calculated. Clinical data were collected during respiratory distress. Results: We enrolled 65 TTN patients. Thirty-one (47.6%) had a sharp echogenicity increase in the lower lung fields (the " double lung point" or DLP sign). On admission, there was no significant difference between patients with and without DLP in Silverman scores (4 +/- 1.5 vs. 4 +/- 2.1; p = 0.9) or LUS scores (7.6 +/- 2.6 vs. 5.6 +/- 3.8; p = 0.12); PaO2/FiO(2) (249 +/- 93 vs. 252 +/- 125; p = 0.91). All initial LUS scans (performed at the onset of distress) and 99.5% of all scans showed a regular pleural line with no consolidation, with only 1 neonate showing consolidation in the follow-up scans. The Silverman and LUS scores were significantly correlated (rho = 0.27; p = 0.02). Conclusion: A regular pleural line with no consolidation is a consistent finding in TTN. The presence of a DLP is not essential for the LUS diagnosis of TTN. A semi-quantitative LUS score correlates well with the clinical course and could be useful in monitoring changes in lung aeration during TTN. (C) 2019 S. Karger AG, Basel