Blood tests in patients with novel coronavirus usually include routine blood tests, C-reactive protein, liver function, kidney function, coagulation picture, blood gas analysis, calcitoninogen, etc. In the early stage, routine blood tests usually show normal or reduced white blood cells and neutrophils, and low lymphocyte count, which is one of the diagnostic bases of novel coronavirus pneumonia. C-reactive protein may be increased in patients with new coronavirus pneumonia, and liver function, renal function, and coagulation picture may not be significantly abnormal in early patients. However, in heavy and critically ill patients, liver and kidney function as well as coagulation images are tested to see if liver injury, renal failure, and coagulation dysfunction are present. In patients with respiratory distress and hypoxemia, blood gas analysis is checked for respiratory failure, and if necessary, tracheal intubation and invasive ventilator application are performed on the patient based on the blood gas analysis results.