Lung ultrasound
LUS was performed using an ultrasound machine with a linear probe (10mHzmedian frequency) with a unique focus on the pleural line and a depth of 5 cm. The acquisitions were achieved by physicians having at least one year experience in pediatric LUS.Images and clips were stored and archived.
As suggested by Soldati et aleach hemithorax was divided in 7 areas:3 posterior (superior, inferior and paravertebral), 2 lateral (superior and inferior) and 2 anterior(superior and inferior).19
We evaluated the presence of pleural irregularities, subpleural consolidations, B-lines and pleural effusions. The lung pattern was classified in: score 0—normal sliding, a regular pleural line and A-lines with fewer than 2 B-lines; score 1—a pleural line indented with multiple well-defined B-lines; score 2—a broken pleural line associated with dark areas and consolidation areas; score 3—large and multiple patches of white lung. To investigate lung fields the patients were positioned in sitting position. Therefore, we summarized the lung ultrasound score in each area.