Table 1.

The eight profiles of the BLUE protocol and their clinical interpretation [30].

BLUE Protocol Profile	Profile Description	Etiology of Respiratory Failure
A-profile	Anterior lung sliding + A-lines + free veins	Exacerbated COPD or Severe acute asthma
B-profile	Anterior lung sliding + lung-rockets	Pulmonary edema
B’-profile A/B-profile C-profile A-V-PLAPS profile	B-profile + abolished lung sliding Half A-profile at one lung, half B-profile at another Anterior lung consolidation A-profile + free veins + PLAPS	Pneumonia
A-DVT profile	A-profile + DVT	Pulmonary embolism
A’-profile	A-profile + abolished lung sliding (+ lung point)	Pneumothorax

BLUE: bedside lung ultrasound in emergency; COPD: chronic obstructive pulmonary disease; PLAPS: posterolateral alveolar and/or pleural syndrome; DVT: deep venous thrombosis.