Hemoptysis (hemoptysis) is bleeding from the respiratory organs below the larynx that is discharged from the mouth by coughing action Hemoptysis must first be differentiated from oral, pharyngeal, and nasal bleeding Oral and pharyngeal bleeding are easily observed as localized foci of bleeding. Nasal bleeding mostly flows from the anterior nostrils, and the foci of bleeding are often found in the lower part of the anterior nasal septum, which is easier to diagnose. Sometimes the bleeding from the posterior part of the nasal cavity is large and can be misdiagnosed as hemoptysis. The diagnosis can be confirmed if blood is seen to flow down the pharyngeal wall from the posterior nostril by nasopharyngoscopy. The former often has a history of tuberculosis, bronchiectasis, lung cancer, heart disease, etc. Before bleeding, there is a cough, throat itching and chest tightness, and the blood is bright red, mixed with foamy sputum, usually without tarry stools; the latter often has a history of peptic ulcer, cirrhosis, etc. Before bleeding, there is upper abdominal discomfort, nausea and vomiting, etc. The blood is brown-black or dark red, sometimes bright red, mixed with food residue and gastric juice. It is mixed with food residue and gastric juice and has tarry stools, which may persist for several days after the vomiting has stopped. There are different definitions for estimating the amount of hemoptysis. Massive hemoptysis usually refers to hemoptysis of more than 600-800 ml or more than 300 ml per hemoptysis within 24 h. Small hemoptysis refers to hemoptysis of less than 100 ml per hemoptysis; moderate hemoptysis refers to hemoptysis of 100-300 ml per hemoptysis. In patients with hemoptysis, despite the application of various tests, the cause of hemoptysis is still unknown in 5-15% of patients and is called occult hemoptysis. Some occult hemoptysis may be caused by non-specific ulcers of the trachea and bronchi, varices, early adenomas, small bronchial stones, and minor bronchial dilatation. The primary cause of hemoptysis must be identified according to the concomitant symptoms of hemoptysis: 1. with fever It can be seen in tuberculosis, pneumonia, lung abscess, pulmonary hemorrhagic leptospirosis, epidemic hemorrhagic fever, bronchial carcinoma, etc. 2.With chest pain It can be seen in lobar pneumonia, pulmonary infarction, tuberculosis, bronchial carcinoma, etc. 3.Choking cough can be seen in bronchial cancer, mycoplasma pneumonia, etc. 4, with skin and mucous membrane bleeding Leptospirosis, epidemic hemorrhagic fever, hematologic disease, connective tissue disease, etc. should be noted. 5, with jaundice should pay attention to leptospirosis, lobar pneumonia, pulmonary infarction, etc. The color of hemoptysis is of auxiliary significance to the diagnosis of clinical disease. Pink foamy sputum indicates acute left heart failure (also known as pulmonary edema); bright red hemoptysis in bronchiectasis; rusty hemoptysis in typical lobar pneumonia; thick dark red sputum in pulmonary embolism; and hemoptysis in mitral stenosis with pulmonary stasis is not bright red, but generally dark red hemoptysis is of auxiliary significance to the diagnosis of clinical disease. The color of hemoptysis can be useful in the diagnosis of clinical diseases. Pink foamy sputum indicates acute left heart failure (also called pulmonary edema); bright red hemoptysis in bronchiectasis; rusty hemoptysis in typical lobar pneumonia; mucousy dark red hemoptysis in pulmonary embolism: in mitral stenosis combined with pulmonary stasis, hemoptysis is not bright red, but generally dark red. Clinical manifestations: 1. Age: young adults – tuberculosis, bronchiectasis, bronchocardial stenosis Over 40 years old with a history of long-term heavy smoking – chronic bronchitis, bronchopulmonary cancer (manifested as persistent or intermittent blood in sputum) 2. ~Hemoptysis: daily hemoptysis of 500 ml or more, or hemoptysis of 300-500 ml at a time. See tuberculosis cavity, bronchiectasis and chronic lung abscess (caused by erosion and rupture of blood vessels). 3. Physical signs Detailed examination of the lungs should be performed. When a chest X-ray is not yet available, to clarify the site of hemorrhage as early as possible, the percussion method can be used. If hemoptysis starts with diminished breath sounds or (and) rales in one lung and good breath sounds in the contralateral lung field, it often suggests that the hemorrhage is on that side. Physical examination can also support some specific diagnosis, such as mitral valve diastolic murmur is good for the diagnosis of rheumatic heart disease; the presence of wheezing sounds in restricted lung and bronchial sites often indicates endobronchial lesions, such as lung cancer or foreign bodies; vascular murmur in the lung field supports arteriovenous malformation; pestle finger is mostly seen in lung cancer, bronchiectasis and lung abscess; enlarged supraclavicular and anterior oblique muscle lymph nodes support metastatic cancer. Examination: 1. Routine blood and urine examination, examination about coagulation mechanism, intra-sputum antacid bacilli, tumor cells, pulmonary aspiration early eggs, sputum common culture and fungal culture, etc. are of great help to clarify the etiology of hemoptysis. 2.X-ray examination: Chest X-ray fluoroscopy should be performed for each hemoptysis, and posterior anterior and lateral chest photography, resting layer and CT photography should be performed if necessary. 3.Bronchoscopy. 4.Electrocardiogram.