1.   Introduction
Mycoplasma pneumoniae pneumonia is a respiratory disease caused by M. pneumoniae infection, and represents a common form of community-acquired pneumonia in children. M. pneumoniae is predominantly transmitted via the respiratory tract(1). Severe cases can involve pleural effusion, atelectasis, mediastinal gas, pneumothorax, and necrotizing pneumonia(2). In a small proportion of children, the disease develops rapidly and becomes critical, often accompanied by respiratory distress. These children may require respiratory support,such as oxygen mask inhalation, intubation, ventilator support, or extracorporeal membrane oxygenation for lung support. The disease can sometimes lead to death(3, 4)Many with this form of pneumonia are affected by the formation of sputum plugs (2).Physical chest therapy, such as manual percussion,is commonly used as an adjuvant therapy to remove sputum (5), although this method is known to be inefficient. High-frequency chest wall oscillation(HFCWO) is a relatively new technique for the clearance of sputum from the chest wall. HFCWO involves an inflatable jacket that is attached to a pulse generator by hoses that enable the equipment to oscillate mechanically at variable frequencies (5–25 Hz).These oscillations are caused by the generator sending air through a hose which causes the vest to inflate and deflate rapidly(6).This technique has been widely used forthe treatment of respiratory diseases, includingpulmonary infection,chronic obstructive pulmonary disease(COPD), and pulmonary fibrosis(6-9).The application of this technique may improve function and help to reduce a decline in lung function; it may also reduce the need for oral antibiotics, reduce the need for hospitalization, and alleviate hypoxia (10). However, little is known about the efficacy of HFCWO for the treatment of children with M. pneumoniaepneumonia. In this study, we analyzed 157 children with M. pneumoniaepneumonia in our hospital. Our aim was to provide reference guidelines for clinical treatment.