Pulmonary reopening is literally the reopening of the lungs and medically refers to the reappearance of inflation within the lung tissue. Under normal conditions the lung tissue, including the respiratory bronchi and alveoli, contains gas and is connected to the fine bronchi, bronchioles, trachea and the outside world. With respiratory movements the gas can move freely in and out and the lung tissue shows alternating movements of diastole and contraction. However, when lung lesions occur, compression, obstruction and pulling of lung tissues can cause pulmonary atelectasis, which means that the gas content of lung tissues disappears, the localized atelectasis is not able to perform diastolic and contractile movements, and the ventilation and ventilation functions of the lungs are impaired. For example, the common causes of pulmonary atelectasis include spontaneous pneumothorax and pleural effusion, etc. Through treatment, the gas or fluid in the chest cavity is expelled and the compression of the lung tissue is released, thus allowing the lung to reopen and restore its function.