呼吸困难是指患者主观感觉空气不足、呼吸费力，主要是呼吸系统和心血管系统疾病所致。问诊应该明确呼吸困难发生的诱因、急缓、加重缓解的因素以及呼吸困难与体位和活动的关系。另外，患者的伴随症状，包括呼吸、心血管及其他系统的症状体征均有助于病因学诊断。

Dyspnea, which is an abnormal sensation of breathlessness, is commonly due to cardiovascular or pulmonary disease.The word ‘abnormal’ is important in the definition because the expected level of breathlessness experienced by healthy individuals while exercising does not qualify as dyspnea.

The physiology of dyspnea remains unclear.Multiple neural pathways can be involved in processes that lead to dyspnea.In acute dyspnea, or shortness of breath of sudden onset, the history, physical examination,and laboratory testing must first focus on potential lifethreatening conditions, including pulmonary embolism,pulmonary edema, acute airway obstruction from anaphylaxis foreign body, pneumothorax, pneumonia,or drug overdoses(e.g., salicylates).In chronic dyspnea,specific conditions to consider include chronic obstructive pulmonary diseases(COPD), asthma, interstitial lung disease, heart failure, cardiomyopathy, gastroesophageal reflux disease(GERD), other respiratory diseases, or hyperventilation syndrome.Dyspnea can also be caused by severe anemia.

D: Hello, sit down please.What’s troubling you?

P: Recently, I feel breathless.I can’t walk more than 500 meters without stopping to rest and catch my breath.

D: How old are you?

P: 50.

D: What’s your occupation?

P: I was a sprinter when young.And I have been a coach after retirement.

D: How long have you been like this?

P: Four weeks.

D: Have you noticed any other symptoms lately?

P: About 4 weeks ago, I had a cold.From then on, I get breathless.Now I feel exhausted most of the time.

D: Have you taken any medications recently?

P: No.

D: Is your breathlessness getting worse, better or staying about the same in the last 4 weeks?

P: I think it has stayed about the same, doctor.

D: Does anything make it better or worse?

P: My breathing is worse when I lie flat.

D: Do you have any cough in the recent 4 weeks?

P: Sometimes in the mornings, but it is not often.

D: Did you bring up anything with your cough?

P: Er...most of the time I coughed up frothy phlegm, but not a lot of it.

D: What color was the phlegm?

P: White.

D: Do your ankles or feet swell?

P: No, I don’t think so.

D: Do you get up at night to pass water.

P: Yes.Sometimes I urinate more than once in the night.

D: Do you have problems in sleeping?

P: Yes, I often wake up at night breathless.

D: How many pillows do you use for sleeping?

P: Two.I used to need only one, but nowadays I need two because I can’t breathe if I lie too flat.

D: Do you have any medical conditions in the past?

P: Well, 5 years ago I had a routine check-up.My doctor told me that I have a heart murmur.But it didn’t bother me and I carried on as usual.

D: Have you ever had any chest pain before?

P: No.

D: Have you had rheumatic or scarlet fever as a child?

P: Sorry, I can’t remember.

D: Have you received any treatment before coming to the hospital?

P: No.

D: Do you smoke?

P: No, never.

D: Does heart disease run in your family?

P: Yes, my father died of a heart attack, and my sister has high blood pressure.

D: May I examine you?

P: Ok.

D: Please take off your clothes except your underwear,lie on the couch.You may use this blanket to cover yourself.Please let me know when you are ready(draw the curtain).

D: I am now going to arrange for your to have a chest x-ray, ECG and echocardiography.After that, please come back so that I may advice you.

P: Doctor, is it that bad?

D: Please don’t worry at this stage.The tests are routine to help us to find out what is causing your symptoms,so that we can advice you the best treatment to make you better.

D: We have found what is causing your breathlessness.You have a narrowed heart valve.Everybody has 4 heart valves.You have narrowing in one of them,called the mitral valve.The condition is called mitral stenosis.It can make you breathless and tired, it can also cause fluid to accumulate in the lungs.

If you wish , I can arrange for you to be admitted for treatment right away.We’ll start you on medications to help remove excess water and make your heart work better, which will alleviate your symptoms.Your narrowed heart valve may or may not need to be replaced or repaired.We will perform more detailed studies of your heart to decide, we can talk more about this later.Do you have any question?

D: Hello.How may I help you?

P: My child has been breathless, coughing and wheezing for a week.He hasn’t been sleeping well at night.

D: How old is your child?

P: He is 6 years old.

D: How bad is the cough?

P: It is quite bad and he has difficulty breathing.

D: Does he bring anything up with the cough?

P: At the end of each coughing spell, he brings up some sputum.

D: What’s the color of the sputum?

P: Most of the time it’s white sticky.

D: Does he have a high temperature?

P: No.

D: Do the symptoms come on like an attack or develop more gradually?

P: Well, since he caught a cold on Tuesday, recently, the coughing and wheezing have become worse.

D: Is it worse any particular time of the year?

P: Usually in the spring and winter.

D: Can he lie flat?

P: When the attack is severe, he can’t lie flat.

D: Do his lips turn blue during an attack?

P: Yes, his lips, and nails also, turn blue.

D: Has he received any treatment before coming to the hospital?

P: Yes, he was treated for asthma, but we did’t completely believe in the treatment.Almost every two months I go to the pharmacy to buy some antibiotics which sometimes help.

D: Has he had asthmatic attacks?

P: Doctors told us he has asthmatic attacks, but all the medications he has tried in the past give only a temporary relief.He is getting worse.

D: I think he is allergic to something which is causing his asthma.He should best be assessed in an allergy clinic.There, they may perform some tests to find out what he is allergic to.For now,I’ll give you some medication to helo alleviate his symptoms.