Medical Tests To Detect COPD

Submitted on March 27, 2012
An ongoing smoker's cough could be a symptom of COPD. Find out which tests specialists recommend.
Medical Tests To Detect COPD

Chronic obstructive pulmonary disease (COPD) is the general term for a lung condition in which the airflow through the lungs is obstructed, resulting in coughing and breathlessness. COPD includes chronic bronchitis and emphysema.

Who should get tested for COPD?

People with the following symptoms may be at risk for COPD

  • Those with a long history of smoking
  • Those with a persistent chronic cough, with or without sputum
  • Those who experience wheezing
  • Those who experience breathlessness that seems to have worsened over time
  • Those who have suffered long-term exposure to air pollutants

Tests for COPD

Your doctor will take into account your signs and symptoms and medical history before diagnosing the condition. You may also need to undergo a physical examination, in addition to certain other tests.

Lung Function Tests

Lung function tests are done to evaluate how much air your lungs can hold and also how quickly you can breathe the air out of your lungs. Spirometry is the most common lung function, which can detect COPD before any symptoms occur.

Spirometry is a painless test in which you will be asked to breathe in deeply. A technician will then ask you to blow into a tube as hard as you can. The tube is connected to a machine called a spirometer, which measures the amount of air you breathe out and how fast you breathe out the air. Your doctor may administer certain medicines, which help to open the airways before asking you to blow into the tube again. The test results before and after taking the medication can then be compared. Spirometry helps to determine how severe the condition is and thus enables your doctor to define treatment goals.

Other conditions such as asthma or heart disease can be ruled as the cause of the symptoms with the help of Spirometry.

Other tests for COPD

In addition to Spirometry, your doctor may recommend certain other tests.

  • Chest X-ray - A chest X-ray helps to detect emphysema, which is a prime cause of COPD. An X-ray also helps your doctor to rule out other causes such as heart failure.
  • CT scan - A computed tomography or CT scan also shows emphysema. Such a scan helps your doctor determine if surgery could benefit your condition. Lung cancer tends to be more common in those with COPD and CT scans are effective in cancer screening.
  • Arterial blood gas analysis - Arterial blood gas analysis measures the ability of the lungs to provide sufficient oxygen to the body and subsequently get rid of carbon dioxide. The analysis of these blood gases gives an indication of your respiratory and metabolic status. The test is done by collecting a small sample of blood from either of three arteries in your body; the radial artery in the wrist, the brachial artery in the arm, or the femoral artery in the groin. The sample is then analysed in a laboratory. The results from this test help your doctor evaluate the severity of COPD.
  • Oximetry - This test is used to determine the level of oxygen saturation in the blood. It is less informative that arterial blood gas analysis, but is helpful in indicating whether oxygen treatment is necessary.
  • Electrocardiogram (ECG) - An ECG is used to detect heart problems that may be the cause of breathing difficulties.
  • Transfer factor for carbon monoxide - This test detects damage to the lungs and the extent of the damage.
  • Alpha-1 antitrypsin (ATT) - This is a rarely done test which measures the levels of the protein antitrypsin or ATT in the body. This protein helps to protect the lungs and people with low amounts of ATT are at risk for emphysema.