Correlation between hypoxaemia and lung ultrasound score in patients presenting to an emergency department with interstitial syndrome: a prospective physiological study.

To assess for the presence of a correlation between lung ultrasound score (LUSS) and ratio between arterial partial pressure of oxygen (PaO) and the fraction of inspired oxygen (FiO) in patients presenting to an emergency department (ED) with interstitial syndrome (IS). Prospective, multicentre, physiological study. Four Belgian hospitals: one tertiary academic centre and three secondary centres.