Modified BLUE protocol ultrasonography can diagnose thrombotic complications of COVID-19 with normal lung ultrasound.

The BLUE protocol provides an excellent step-by-step approach for diagnosis of acute dyspnea. Adding FECHO (Focused Echocardiography) to the BLUE protocol completes the picture and helps make solid diagnoses, especially in submassive and massive PE (Pulmonary embolism). COVID-19 infection can present with thrombotic manifestations like DVT (Deep vein thrombosis) and PE with no ultrasonographic evidence of lung parenchymal affection.