Background Lung ultrasound (LUS) has become an important method for diagnosis and monitoring of lung disease. Advantages over chest radiography include precision, low cost, simplicity, bedisde care and specially avoids radiation.

Respiratory failure in late preterm infants (>32 weeks gestational age) and term infants is usually based on clinical and radiological (x-ray) manifestations.

However etiologic diagnosis in the early stage is difficult (respiratory distress syndrome (RDS), surfactant consumption or transient tachypnea) raising doubts in treatment (ventilation, surfactant administration, antibiotics) and short and medium term evolution.

Aims 1. Assess whether LUS is as effective as the usual clinical diagnostic methods in the neonatal respiratory distress in late pre terms infants and term infants.

2. Check if initial LUS has a prognostic value in the need for respiratory support.

Materials and methods From January through April 2014 were enrolled all late preterm infants and term infants consecutive admitted in NICU with respiratory distress (prenatal malformation diagnosis were excluded).

A blind neonatology performed LUS at adminission and through first hours income without interrupting routine neonatologist clinical management.

Results 50 patients were enrolled (53 male). Main results are shown in table 1. LUS diagnosis were made based in Lichtenstein and Coppeti standards.

Conclusions Lung ultrasound can differentiate those patients with NNT from other causes of neonatal respiratory distress may be an extremely useful tool for respiratory prognosis and can reduce the number of chest radiographs performed in these patients.