COVID-19 may predispose patients to thrombotic disease, both in venous and arterial circulation, due to excessive inflammation, endothelial dysfunction, platelet activation, and many other prothrombotic factors such as tissue injury, decrease of natural anticoagulants, and stasis.Despite the use of antiviral, anti-inflammatory drugs, anticoagulant therapy, and even invasive mech. ventilation, many patients progress to a critical stage, characterized by acute respiratory distress syndrome (ARDS) and shock.We describe here two patients, in whom thrombolysis using recombinant streptokinase was used to treat refractory hypoxemia after suspecting pulmonary micro- and macro-thrombotic disease.