Clinical hemoptysis is difficult to accurately estimate, and the actual bleeding volume often does not match the hemoptysis volume due to the presence of ineffective respiratory lumen and the fact that some of the hemoptysis is swallowed through the mouth. In general, a hemoptysis volume of more than 400mL in 24 hours or a single hemoptysis of more than 100mL, and a hemoptysis volume of more than 600mL in 48 hours are commonly known as hemoptysis. For some elderly patients and those with poor cardiopulmonary function, the volume of hemoptysis exceeding 100mL in 24 hours is commonly known as hemoptysis. Hemoptysis is one of the critical respiratory diseases, which can cause hemorrhagic shock and asphyxia and other life-threatening conditions, so patients with hemoptysis need to take timely and effective treatment to avoid serious consequences.