Flatulence of the lungs refers to emphysema, and there are many causes of emphysema, such as air factors, long-term smoking, chemical stimulation, infectious factors and so on. 1. Air factors: poor air quality, being in the air with a lot of harmful gases, such as chlorine, sulfur dioxide, etc., for the human airway will cause a certain degree of damage, triggering emphysema. 2. Long-term smoking: smoking will cause too many oxygen free radicals, which will lead to the release of excessive proteases from neutrophils, which will damage the elastic fibers of the lungs, thus inducing emphysema. 3. Chemical stimulation: patients in the long-term dust, or chemical substances, can also induce lung distension, such as industrial exhaust, indoor air pollution, etc., may induce emphysema. 4. Infectious factors: long-term infection of chronic bronchitis can cause the alveolar walls, alveoli fused with each other, thus forming emphysema. There are many causes of emphysema, it is recommended that patients go to the hospital in time to improve the examination, a clear diagnosis, do not ignore the symptoms, take it lightly.