Basic notions of lung ultrasound in neonatology.

Lung ultrasound (LU) has gained ground in the diagnosis of most respiratory conditions present since birth. It is highly sensitive to variations in air content and pulmonary fluids and functions as a true densitometer of the lung parenchyma with a sensitivity superior to that of radiological studies. A LU is a non-invasive, fast and easy tool that can be used at the patient's bedside and, unlike conventional radiology, does not pose risks of radiation. In addition, a LU provides real-time dynamic information in a variety of neonatal settings and, like heart and brain examinations, can be performed by the neonatologist. The objective of this article is to describe the main artifacts and images that can be found in the neonatal LU, as well as the different aeration patterns, and to highlight their usefulness in the study of the most frequent respiratory disorders of neonates.