Dyspnea mainly includes three types: 1, inspiratory dyspnea: the obstruction site is located in the upper respiratory tract, including the mouth, nose, pharynx, larynx, trachea, manifested as inspiratory effort, which will lead to the suprasternal fossa, supraclavicular fossa, inferior glabella and even the intercostal space depression, respectively, known as the three concave signs and four concave signs; 2, expiratory dyspnea: the obstruction site is in the lower respiratory tract terminal bronchus, mainly seen in lung disease, manifested as 3, mixed dyspnea: both upper and lower respiratory tract obstruction, relatively rare, mainly seen in older patients, combined with systemic diseases, not only upper respiratory tract pathology, but also combined with lower respiratory tract pathology, such as chronic obstructive pulmonary.