DIAGNOSIS

The doctor diagnoses COPD based on signs and symptoms, medical and family history, and the results of some tests.

Your doctor may ask if you smoke or have been in contact with lung irritants, such as secondhand smoke, polluted air, chemical vapors or dust.

If you have a permanent cough, tell the doctor since when you had it, how much you cough and how much expelling mucus when you cough. Also tell him if there are other people with COPD in his family.

The doctor will examine you and auscultate your chest with the stethoscope for wheezing (wheezing or shrieking when you breathe) or other abnormal noises. You may also recommend one or more tests to diagnose COPD.

Lung function tests

Pulmonary function tests measure the amount of air you can inhale and exhale, how quickly you can get air out of the lungs and how well the lungs pass oxygen to the blood.

The main test to diagnose COPD is spirometry. Other lung function tests may also be performed, such as the determination of lung diffusion capacity. Read Pulmonary Function Tests for more information.

Spirometry

In this painless test a technician will ask you to breathe deeply and then blow as hard as possible through a tube that is connected to a small device. The device is called a spirometer.

The spirometer measures the amount of air you exhale or take out of the lungs and how quickly it does it.

The patient breathes deeply and then blows hard through a tube connected to the spirometer.

The spirometer measures the amount of exhaled air. It also measures the speed with which it was exhaled.

The doctor can make you inhale a medicine that clears the airways and then ask you to blow through the tube again. You can then compare the results that were obtained before and after taking the medicine.

Spirometry can detect COPD long before symptoms occur. The doctor can also use the results of this test to find out how severe the COPD you suffer and help you set the treatment goals.

The test results can also be used to find out if any other illness, such as asthma or heart failure, is causing your symptoms.

Other tests

Your doctor may recommend other tests, such as:

A chest radiograph (in English) or a CT scan of the chest. In these tests, images of structures inside the chest, such as the heart, lungs and blood vessels, are obtained. Images may show signs of COPD. They can also show if any other disease, such as heart failure, is causing the symptoms.

An analysis of arterial gases. This blood test measures the concentration of blood oxygen in a sample that is obtained from an artery. The results allow you to determine how severe COPD is and if you need oxygen therapy.