Diffusion function is a measurement in gas exchange function. It is used to evaluate the efficiency of gas exchange by the alveolar capillary membranes, as well as the examination of lung function. Decline should be noted as a possibility caused by respiratory diseases. What are the preventive methods of decreased gas diffusion function? 1.Keep the respiratory tract open. 2.To keep enough rest and drink enough water, especially with fever children. Diet should be given light and easy to digest high-calorie, high-protein fluid or semi-fluid food, eat more fruits and vegetables, do not eat stimulating food. 3, pay attention to keep warm, the patient himself has a disease, resistance is very poor, to avoid getting cold again. 4.The air in the living room should be new moist and circulating. Avoid smoke, dust and irritating gas stimulation. Keep the air in the room fresh, keep the temperature at 18-22 ℃, humidity at 50%-70%, avoid the stimulation of smoke and dust, smokers advised to quit smoking. 5. Ask the patient to drink more water, not less than 3000ml per day, in order to facilitate the excretion of metabolites. Assist in oral care, encourage more gargling, and apply lip oil when lips are dry. Most of the antibiotics are ineffective, and there is still a lack of effective treatment, which often shows progressive development and eventually respiratory failure and heart failure. The motherland medicine has some efficacy in the treatment of this disease. Through summarizing and analyzing the patients, we believe that the main mechanism of this disease is the deficiency of lung and kidney, stasis, phlegm, heat and other pathogenic evils, and that the treatment of tonifying the lung and kidney, activating blood circulation, softening and dispersing knots, and resolving phlegm and clearing away heat can slow down the process of the disease and alleviate the clinical symptoms, such as alleviating shortness of breath, improving the function of the lungs, and improving the partial pressure of blood oxygen, so that the patients can carry out a certain degree of physical activities, and alleviate the patients’ mental stress, thus improving the quality of life. Thus improving the quality of life. Enhancing the patient’s immunity and reducing the number of colds can prevent the condition from deteriorating due to infection. If necessary, combining with hormone can reduce the side effects of hormone and enhance the therapeutic effect. Interstitial pneumonia must first be clearly diagnosed, and then under the guidance of experienced physicians, long-term treatment, do not take it lightly. The patient’s psychological activity is also important to the treatment, optimistic and cheerful people than depressed people with a longer life. Do not be pessimistic and anxious.