Here is a personal checklist that will enable you to determine whether you should consult your physician.
Does COPD run in my family?
Do I smoke?
Am I short of breath more than others?
Do I cough?
When I cough, do I cough up yellow or green mucus?
A careful history, with a focus on cough, expectoration, shortness of breath, wheeze, and the duration of these symptoms is basic. A careful smoking history and an occupational history detailing possible dust and/or irritant exposures are also needed. Most patients have had some telltale symptoms for years before they come to a doctor for an evaluation. None of these symptoms is specific or diagnostic by itself. A careful family history in reference to close relatives with COPD is important because COPD runs in families. Some common questions often asked by doctors or nurses to help evaluate the patient are listed in Tables 1 and 2. It is important to talk about the patient’s duration of symptoms, lifestyle, work environment, and problems related to the illness.
A complete physical examination should be performed during your first visit to a doctor.
Table 1: Questions a doctor may ask:
How long have you had cough, shortness of breath, or wheeze?
Have you seen many doctors for it? What are you now doing to treat it?
How many days did you miss from work last year because of the lung problem?
Were you in the hospital for it? How long and how many times last year?
Describe your usual good day.
Do you have more good days than bad days in a week? What are you able to do when you are feeling your very best?
Who do you live with?
What recreation do you prefer?
Table 2: More Questions Your Doctor or Nurse May Ask:
How does the emphysema or chronic bronchitis bother you?
When does it bother you the most?
What have you learned to do that helps you to live with it?
Does it ever embarrass you to have lung trouble?
Your physician will thoroughly examine your chest, observe your breathing patterns, and perhaps monitor how hard you are working to breathe. He or she will note the degree of over-inflation by percussion (tapping over the lungs). He will listen to your chest with a stethoscope to hear the air flow in and out of your lungs. The intensity (loudness) of the sounds is helpful. Noises caused by mucus or inflammation are also noted.
The physician or nurse will also listen to your heart sounds to determine the rate and rhythm of your heart and any signs of heart strain that may accompany advanced stages of COPD. The examination itself is not very accurate in determining the severity of the abnormality, however. A physical examination may be normal even in the early stages of significant disease. This is because airflow abnormalities are usually moderately advanced before they can be detected with a stethoscope!
Chest x-rays are not very useful in assessing the patient with COPD. By the time the x-ray is clearly indicative of the disease, the neighbors usually know the diagnosis! However, the x-ray may show over-inflation of the lungs, which is common in emphysema. X-rays are also valuable in finding other abnormalities such as shadows which may indicate coexisting lung cancer. Lung cancer and COPD often occur together because both are caused by smoking. The heart and the large vessels to and from the heart can also be seen on a chest x-ray and give some indication about associated heart strain, but only in advanced stages of disease. However, the chest x-ray can be completely normal, even when the patient has a significant degree of COPD. The x-ray, though traditional, is not a good way of diagnosing or evaluating COPD.
The EKG also is not useful in evaluating patients with COPD. In very advanced disease, EKG abnormalities are usually evidence of strain in the right side of the heart, i.e., that portion of the pump that propels blood from the tissue back through the lungs to take on oxygen and get rid of carbon dioxide.
Culturing the sputum of patients with emphysema and/or chronic bronchitis is almost useless. The common bacteria are well-known, and today physicians properly prescribe antibiotics based on their knowledge of the most common organisms and will do so if sputum increases in volume and becomes colored. Yellow or greenish sputum is almost always infected and requires antibiotics.
Measuring Lung Capacity
A simple device called a spirometer measures your lung capacity. During this test you take a deep breath, as deeply as you can, and blow it out all at once into a machine that records airflow and capacity. The total amount of air blown out of fully inflated lungs is called the vital capacity. Since the air is forced out by your muscular effort, it is called forced vital capacity (FVC, newer term FEV6). This test measures the useful size of your lungs. The rate of airflow tells how open the air passages are and how well the lungs can empty, or how well their elasticity is functioning. The lungs empty somewhat like an inflated balloon. Remember how a flabby or overused balloon empties slowly and incompletely? This is a lot like the lung with emphysema. The airflow test is called the forced expiratory volume in one second, since this airflow is timed or measured over the first second of exhalation. The symbol for forced expiratory volume in one second is FEV1. These two tests, the FVC and FEV1, reveal all your doctor needs to know about your lung capacity and airflow. These two numbers are somewhat similar to systolic and diastolic numbers in blood pressure readings. We believe that knowledge of FVC and FEV1 is as valuable and important to health promotion as knowledge of blood pressure. These tests measure your lung power, which is essential to your continuation and enjoyment of life.
Normal values are based on age, sex, and height. Younger and taller individuals have greater airflow and air volume than shorter or older people. Men have slightly greater airflow and air volume compared with women of the same age and height.
Self-Testing- Try It Yourself
Normal lungs have large volume, and they empty quickly because airways are open and lungs are elastic. You can do a little checking yourself with a stopwatch. Take a full breath; hold if for one second. Then, with your mouth open, blow out as hard and fast as you can. Your lungs should be completely emptied – meaning that you can blow no more air out even though you try– in no more than 4 to 6 seconds.
If one takes longer to blow out all the air, it means that airflow is obstructed or limited. Today we use the term “limited” because this airflow reduction can be due to either a loss of lung elasticity (emphysema) or problems with airways (asthmatic or chronic bronchitis). See how simple it is!
Unfortunately, routine lung function tests have been accepted all too slowly. No person would go for a complete check-up if the physician did not examine the eyes, ears, nose, throat, listen to the heart and lungs, feel the abdomen for any abnormal masses, and examine the genital, rectal, and pelvic areas. All these are routine, and to supplement them, appropriate laboratory blood and urine tests are done, plus an electrocardiogram and, usually, a chest x-ray. Unfortunately, none of these examinations or tests identifies early COPD.
Only spirometric measurements of the kind we have just described can identify the patient who is just beginning to develop a lung abnormality.
When one considers that the disease process finally resulting in disability may go on for 20 to 30 years, doesn’t it make sense to identify the problem early and to take immediate corrective action? The answer must be yes if you are to a enjoy a long happy life.
Very simple devices for measuring lung capacity are becoming popular. One such device is called a peak flow meter, which measures the greatest airflow rate you can produce. A man’s normal figure is around 600 liters per minute, and a woman’s is 370 liters per minute. Both are normal. (The lower value for women is because of their shorter stature and female sex). Some physicians instruct their patients to use peak flow meters at home to study the response to treatments designed to open up their air passages. Another new device called a spirometer accurately measures forced vital capacity. These measurements of both volume capacity (forced vital capacity) and flow can give a good estimate of the mechanical function of the lungs. (Newer, less expensive pulmonary function testing equipment is now readily available for use in primary care physician offices).
Other tests are used in more advanced stages of disease to obtain additional knowledge about the lungs’ function. One such test is the blood gas measurement. A small amount of blood is drawn from an artery by a small needle and syringe. This blood is analyzed to measure the amount of oxygen and carbon dioxide it contains. This test is used to assess more advanced stages of emphysema and chronic bronchitis and is needed when the physician is considering prescribing oxygen and in cases of serious and emergency illness.
Another simple method of measuring blood oxygen is with an instrument called an oximeter which is widely used today. It is popular because it does not require arterial blood sampling. However, it is not as accurate as arterial blood measurement, and it tells nothing about the levels of carbon dioxide or acid (pH) in the blood. The pulse oximeter measures blood oxygen by reflected light. This test is easy and painless and will be much more widely used in the future.
Additional lung function tests such as the diffusion test also measure the integrity of the air-blood interface, or alveolar capillary membrane. Numerous additional tests are used for research purposes, but they do not have any practical value at the present time.
In summary, adequate evaluation of patients with all stages of COPD is within the reach of all doctors and their patients. The approach is simple and straightforward. All patients with shortness of breath, cough, wheeze – particularly those with family history of COPD and absolutely all smokers – should insist on this crucial evaluation.
Answers from Dr. Thomas Petty, Professor of Medicine, University of Colorado.