Fig. 4.

Lung ultrasound scores and oxygenation in patients undergoing NIV. Data are from the first (Start) and last (End) examination while receiving NIV. Patients are categorized according to outcome at the end of NIV treatment; the endpoint was defined as the combination of ICU admission for invasive ventilation and/or in-hospital death (whichever occurred first). Asterisks indicate statistically significant differences at p < 0.05. ABG arterial blood gas analysis, ICU intensive care unit, NIV noninvasive ventilation