Children who always hold their breath out uttering may be associated with upper airway obstruction, respiratory diseases, cardiovascular system diseases, etc. 1. Upper respiratory tract obstruction: such as rhinitis, nasal polyps caused by nasal stenosis, congenital laryngeal cartilage dysplasia, tracheal foreign body, etc. can cause shortness of breath, breathlessness and panting. 2. Lower respiratory diseases: acute bronchitis, asthmatic bronchitis, bronchitis, bronchial asthma, pneumonia, etc. can cause phlegm, chest tightness, resulting in breathlessness and panting. 3. Cardiovascular diseases: congenital heart disease, viral myocarditis, infective endocarditis and other cardiovascular diseases can cause chest tightness, shortness of breath, palpitations, resulting in breathlessness and panting. When your child suffers from breathlessness, it is recommended that you seek medical attention in a timely manner to treat the cause of the problem under the guidance of a specialist.