Since last December, the outbreak of 2019-nCoV in Wuhan has caused ever-increasing attention and public panic all over the world. Up to February 9, 2020, 40,171 patients had been diagnosed with 2019-nCoV infection, including 6484 (16.14%) severe cases and 908 deaths (2.27%). Compared to SARS and MERS, 2019-nCoV appears to be much more contagious but less lethal, as most patients have mild symptoms and good prognosis1,2. However, according to the Chinese government’s daily report, 13.2–21.3% of patients with 2019-nCoV infection developed into severe or fatal illness (Fig. S1a), which is characterized by the rapid development to acute respiratory distress syndrome (ARDS) or septic shock. Along with an increasing number of confirmed cases, the cumulative total of severe patients with 2019-nCoV is growing (Fig. S1b). Treatment of these critically ill patients is becoming one of the major challenges we are facing.