Patients: What is the importance of oxygenation for patients with chronic obstructive pulmonary disease? Prof. Shen Ning: Chronic obstructive pulmonary disease is a chronic respiratory disease, and when the disease progresses to a late stage, many patients will become hypoxic. At this time, we may have to recommend oxygen to patients. However, it is important to emphasize that not all patients need oxygen, but only when the disease is severe or when the patient really shows signs of hypoxia, the doctor will recommend oxygen. Patient: What are the conditions when a patient needs oxygen? Prof. Shen Ning: From the doctor’s point of view, there are clear indicators for patients who need oxygen, which are roughly divided into three categories: first, when the patient has difficulty in breathing, oxygen can be recommended for a short period of time; second, when the patient is exercising, due to the increased oxygen consumption of the organism itself, at this time there is hypoxia, oxygen can also be absorbed; third, long-term continuous oxygen therapy, the patient has developed pulmonary heart disease, pulmonary hypertension, poor cardiac function, etc. Thirdly, if the patient has developed pulmonary heart disease, pulmonary hypertension, poor cardiac function, etc., the patient will be advised to inhale oxygen. In fact, what we usually call oxygen is long-term oxygen therapy. In general, long-term oxygen therapy is indicated when the partial pressure of oxygen on arterial blood gas analysis is below 55 mm Hg or when the peripheral oxygen saturation monitoring is below 88. Regarding the testing of these two indicators, they are usually checked twice within three weeks, which ensures that the patient does meet the indication for long-term oxygen therapy. Patient: If a patient with chronic obstructive pulmonary disease does not feel hypoxic but has difficulty breathing during exercise, is it possible to administer oxygen only during exercise? Prof. Shen Ning: This is possible. In normal people, oxygen consumption increases during exercise, but the compensatory mechanism of the body can ensure that there is no lack of oxygen. However, in patients with chronic obstructive pulmonary disease, the compensatory mechanism is very poor, and oxygen deprivation may occur during exercise. If the patient does have significantly worse dyspnea during exercise, appropriate oxygen inhalation is allowed. In addition, in addition to exercise, patients with chronic obstructive pulmonary disease are most likely to suffer from hypoxia at night. Patients: Some patients have very severe symptoms of dyspnea, is it possible to apply oxygen therapy without examination at this time? Prof. Shen Ning: The symptoms of patients with chronic obstructive pulmonary disease are not always consistent with the objective examination. Sometimes, we see patients with very severe respiratory symptoms, but after some objective examinations, we find that the situation is not that severe. For this sudden onset of respiratory distress, oxygen can be administered for a short period of time, but long-term oxygen therapy still needs to meet the indications. Patients: Is it also good for the body to inhale oxygen when the patient with chronic obstructive pulmonary disease does not meet the oxygen indications? Prof. Shen Ning: The current view is that we still don’t recommend patients to inhale oxygen at home in cases where there is no real hypoxia. Mechanistically, too much oxygen may produce oxygen free radicals, which can aggravate airway inflammation. In addition, both oxygen cylinders and oxygen concentrators have some precautions when applied at home, such as fire prevention. Meanwhile, many patients with chronic obstructive pulmonary disease smoke, which creates some potential dangers. In addition, medical costs can be saved from socio-economic factors. However, patients with financial conditions can also prepare an oxygen device at home and inhale oxygen for a short time to relieve symptoms during exercise or acute respiratory distress, but it is not recommended to inhale oxygen for a long time.