Spring and summer alternate, and it should have been a season of energy. However, some people cannot muster up their energy and feel suffocated at the slightest movement. According to incomplete statistics, from March to May each year, nearly 30% of patients in respiratory clinics seek medical attention due to breathing difficulties. As the saying goes, "one can breathe in one breath," and it is very uncomfortable to not catch a breath. This type of situation is often described by patients as "holding their breath", "shortness of breath", "chest tightness", "insufficient breath", etc. Doctors collectively refer to it as "difficulty breathing". Difficulty breathing patients are very common in daily life, but they are often at a loss due to complex causes and diverse treatment plans, and some patients delay seeking medical treatment due to mild symptoms. Today, doctors have compiled a "Guidelines for seeking medical treatment for dyspnea" based on clinical experience, hoping to help patients detect physical abnormalities as soon as possible and seek medical treatment correctly and effectively. 1. What causes dyspnea? Dyspnea is a common symptom in clinical practice, which refers to the subjective feeling of insufficient air or difficulty breathing. Objectively, it manifests as changes in respiratory frequency, rhythm, and depth, which can be caused by diseases of multiple systems such as the lungs, heart, blood, nerves, and mind. Sometimes, easily overlooked mild breathing difficulties may be related to some serious diseases, such as pulmonary embolism, myocardial infarction, pneumothorax, etc; Some seemingly severe breathing difficulties are not caused by organic diseases, but by psychological factors. Essentially, difficulty breathing is a manifestation of the body feeling insufficient oxygen. So, how is oxygen transported and utilized within the human body? The respiratory system plays a crucial role in this process. The respiratory system consists of the nose, pharynx, throat, trachea, bronchi, and lungs, responsible for providing oxygen to body cells and expelling carbon dioxide. Oxygen enters the alveoli through the respiratory system, then enters the bloodstream through the alveolar walls, and finally is transported by the bloodstream to various organs throughout the body. Therefore, any problems that arise in the process of oxygen inhalation, transportation, and utilization may cause breathing difficulties, and the underlying causes are naturally hidden within it. The main causes of dyspnea include the following four types. 1. Obstruction or narrowing of the oxygen inhalation pathway from the nasal cavity to the alveoli can cause breathing difficulties. Common diseases include upper respiratory tract infections (common cold), foreign bodies in the trachea or bronchi, chronic obstructive pulmonary disease, bronchial asthma, bronchiectasis, lung cancer, etc. 2. The end of the respiratory system is the alveolar wall, which determines whether oxygen exchange can be successful. If there are conditions such as alveolar filling, interstitial thickening, and pulmonary vascular obstruction, it can lead to oxygen exchange disorders, resulting in breathing difficulties. Common diseases include viral pneumonia, pulmonary interstitial fibrosis, pulmonary congestion or edema caused by heart failure, pulmonary thromboembolism, etc. 3. Decreased red blood cells can cause moderate to severe anemia. After oxygen enters the bloodstream, red blood cells need to be transported to various organs. When the number of red blood cells decreases or quality problems occur, insufficient oxygen transportation can also cause breathing difficulties. Common diseases are moderate to severe anemia. 4. The brain, nerves, and muscles are unable to regulate respiration properly. Every breath and inhalation of a person is commanded by the brain, which then transmits commands through the nervous system and respiratory related muscles execute commands. If any link in this information pathway is incorrect, it can lead to respiratory movement disorders, resulting in breathing difficulties. Common diseases include cerebral hemorrhage, myasthenia gravis, chest wall injury, and respiratory muscle paralysis caused by medication. In addition to the four reasons mentioned above, psychological problems such as mental tension and anxiety caused by a fast-paced and high-pressure lifestyle can also lead to breathing difficulties. 2. Beware of the hidden dangers of mild respiratory distress. The severity of respiratory distress varies greatly from mild chest tightness and shortness of breath to severe respiratory distress. The doctor suggests that once the symptoms of breathing difficulties affect the patient's daily life, they should promptly seek medical attention at a reputable hospital. If a patient is found to have severe breathing difficulties, loss of consciousness, or purple lips, the caregiver should immediately call 120 for help to prevent the condition from progressing and endangering life. However, a more challenging situation is that some elderly people with poor sensitivity and strong tolerance to hypoxia, or patients with limited mobility after trauma or surgery, are prone to ignoring this discomfort due to lack of sensation for mild breathing difficulties, thus missing the best opportunity for medical treatment. How can patients accurately identify mild breathing difficulties and seek timely medical attention? Usually, judgments can be made from the following aspects. One is that in a quiet and inactive environment, there is no difficulty breathing, but after brisk walking, mountain climbing, or doing heavy physical work, there is a feeling of rapid breathing, difficulty breathing, and a noticeable decrease in physical strength or inability to compare to peers, which is known as "frequent wheezing". The second symptom is dyspnea accompanied by a whistling sound between the throat, obvious difficulty in exhaling, and may be accompanied by cough, absence of phlegm, or insufficient phlegm. Some symptoms are seasonal, known as "chronic, recurrent wheezing and coughing.". Thirdly, one often feels fatigued, accompanied by persistent soreness in the chest, back, and between the ribs on both sides, which is more pronounced in the afternoon and at night, and alleviates after rest or in the morning. This may be due to increased respiratory frequency and amplitude, leading to respiratory muscle fatigue. The fourth is that there is no obvious discomfort during the day, but sleeping at night requires raising the pillow, otherwise you will feel chest tightness, and even uncomfortable to the point where you need to sit up to relieve it. Some patients may also have edema in both lower limbs, which is known as "wheezing when lying flat". The fifth symptom is that some elderly people with disabilities suddenly experience symptoms such as increased breathing, flapping of their nasal wings, drowsiness, decreased activity, decreased expression, poor eating habits, and urinary and fecal incontinence, and their fingertip blood oxygen saturation is less than 93%, which is known as "silent hypoxia". The above 5 situations may not necessarily be expressed as chest tightness or shortness of breath or understood as difficulty breathing when patients are in them, but in reality, these are likely warning signals for certain potential diseases that need to be taken seriously and seek timely medical attention. 3. The preferred visiting department varies depending on the disease. As mentioned above, there are many diseases that can cause breathing difficulties. It is a challenge to identify the characteristics of one's own breathing difficulties and accurately locate the visiting department. In clinical practice, difficulty breathing varies depending on the severity or characteristics of the condition, and the preferred department and examination content are different. Below are several common situations for your reference. Urgent breathing difficulties or distress, accompanied by cyanosis of the lips and mouth, especially accompanied by blurred consciousness, fainting, coma, etc., require emergency call 120, and the patient should be sent to the hospital for emergency treatment; Difficulty in inhaling and accompanied by a high pitched whistle between the throat may be a problem of upper respiratory tract obstruction. It is recommended that patients seek medical attention from an ear, nose, throat or respiratory department and undergo laryngoscopy or bronchoscopy examination; If one cannot feel breath, accompanied by coughing, sputum production, wheezing, or has a history of recurrent attacks for many years, smoking, pollen allergy, decreased activity tolerance, etc., it may be a chronic airway disease (such as chronic bronchitis, asthma). It is recommended that the patient seek medical attention from a respiratory department and undergo chest CT, lung function, bronchial provocation test, and other examinations; After the activity, the patient experiences chest tightness and shortness of breath, accompanied by swelling or chest pain in both lower limbs, coughing with pink phlegm, and a history of heart disease, which may be heart failure. It is recommended that the patient seek medical attention from the cardiology department and undergo echocardiography, electrocardiogram, and other examinations BNP and other inspections; Postoperative chest tightness accompanied by unilateral lower limb swelling, especially recent lower limb trauma, fractures, and surgical history, may indicate pulmonary thromboembolism. It is recommended that the patient seek medical attention from a respiratory department and undergo D-dimer, echocardiography, and pulmonary artery enhanced CT examination; Chest tightness and shortness of breath accompanied by pale complexion, lips, and conjunctiva, often accompanied by fatigue, may be caused by anemia. If black stool is also present, it is recommended that the patient seek medical attention from the digestive department. If menstrual flow increases, it is recommended to seek medical attention from the gynecological department. If there is no clear bleeding situation, it is recommended to seek medical attention from the hematology department; Respiratory rhythm disorder accompanied by dizziness, headache, unclear speech, unilateral limb numbness, and even consciousness disorders may be cerebral hemorrhage or cerebral infarction. It is recommended that the patient seek medical attention in the neurology department and undergo head CT and MRI examinations; Emotional excitement (arguments, anger) and mental stress can cause shallow and rapid breathing accompanied by limb numbness and weakness during bowel movements, while stable emotions, scattered attention, long inhaling or sighing, and relief after exercise are mostly caused by psychological factors. It is recommended that patients seek medical attention from a psychiatric department. 4. It is crucial for patients to accurately describe their condition precisely because the causes of breathing difficulties are diverse, the symptoms are diverse, and the diagnostic process may not necessarily be smooth. When seeking medical treatment, patients should first try to recall and accurately describe the causes of breathing difficulties, such as whether they are related to smelling irritating odors, seasons, activities, etc. The respiratory distress caused by different diseases varies, and accurate and specific triggers can sometimes play a decisive role in the diagnosis of diseases. Secondly, patients should pay attention to the onset and duration of dyspnea, whether it is intermittent or persistent? Is it heavy in the morning, afternoon, or evening? How long has it been since symptoms appeared and medical attention was sought? The characteristics of the disease and the length of its course can help doctors delineate the scope of the disease. At the same time, attention should also be paid to factors that exacerbate and alleviate breathing difficulties, such as whether they are related to exercise, body posture, surrounding environment, and other factors. In addition, for other symptoms related to breathing difficulties, patients should also inform their doctors, such as whether they are accompanied by symptoms such as cough, sputum, hemoptysis, chest pain, fever, lower limb edema, etc. The more comprehensive the symptom description, the more it can show the full picture of the disease. The patient's detailed medical history should not be concealed, including basic medical history, medication use, allergies, and recent tests and tests. On the one hand, it can avoid repeated examinations, and on the other hand, it is convenient for doctors to extract useful information from it and make more accurate judgments about the disease. In summary, dyspnea is a common and complex clinical symptom that involves multiple systemic diseases, and its appearance may indicate the presence of certain diseases or pathological processes within the body. This medical guide can help people better identify breathing difficulties, go to the corresponding department for targeted treatment according to different symptoms, and avoid repeated medical treatment causing delays in the condition. At the same time, accurately describing the characteristics of breathing difficulties (triggers, duration, exacerbation or relief factors, etc.) and conducting necessary examinations and tests will help doctors quickly identify the cause and develop the best diagnosis and treatment plan. (Li Jie, Deputy Chief Physician and Chief Physician of the Respiratory and Critical Care Medicine Department at Beijing Anzhen Hospital)