Primary (Day −1 to 10): the time to oxygen saturation recovery to normal level (≥97%), the proportion of patients with normal level of oxygen saturation(≥97%)
Secondary (Day −1 to 10):
The degree of remission of symptoms of patients, including: fatigue, nausea, vomiting, chest tightness, shortness of breath, and so forth, the time to the myocardial enzyme spectrum recovery to normal after treatment, the proportion of the patients with normal myocardial enzyme spectrum after treatment, the time to the electrocardiogram recovery to normal level after treatment, the proportion of the patients with normal electrocardiogram after treatment, the time to the hemodynamics recovery to normal after treatment, the proportion of the patients with normal hemodynamics after treatment, the time to exacerbation or remission of the disease after treatment, the proportion of the patients with exacerbation or remission of disease after treatment, the proportion of patients who need other treatment (e.g., heparin, anticoagulants) due to microcirculation disorders, the all‐cause mortality rate, the proportion of patients with acidosis, the total duration of the patients in‐hospital, the total duration of oxygen inhalation during treatment, the oxygen flow rate during treatment, the oxygen concentration during treatment