Tests Used for an Emphysema Diagnosis

Emphysema is a form of chronic obstructive pulmonary disease, or COPD, that involves damage to the alveoli, the tiny air sacs in which the exchange of oxygen and carbon dioxide takes place. When this damage occurs, it can make it more difficult to breathe.

You and your healthcare provider may be concerned if you have any signs or symptoms of emphysema, such as shortness of breath, a chronic cough (with or without sputum production), reduced exercise tolerance, or unintended weight loss.

Diagnosing emphysema often involves evaluating your lung function, as well as making sure you don’t have other causes of your symptoms. This article looks at some of the tests used to make this diagnosis.

History and Physical

Doctor checking patient's heart and breath

Darren Kemper / Corbis / VCG / Getty Images

The presenting symptoms and findings made during a physical examination provide your practitioner with the initial clues to any health problem, emphysema included.

During your office visit, your healthcare provider will ask you a number of questions related to your history. This will include asking about the most common symptoms such as:

  • A persistent cough, with or without coughing up sputum
  • Rapid breathing (tachypnea): A normal respiratory rate in adults is 12 to 18 breaths per minute.
  • Shortness of breath
  • Less ability to exercise than in the past
  • Weight loss
  • Reduced appetite
  • Wheezing
  • Poor sleep
  • Depression

They will also ask you about risk factors for emphysema, such as smoking, secondhand smoke, and home and occupational exposures to chemicals and other substances.

It’s important to note that while emphysema is often caused by smoking, people who have never smoked may develop the disease as well.

You will also be asked about your family history. Some causes of emphysema, such as alpha-1-antitrypsin deficiency, run in families. It’s especially important to let your practitioner know if any members of your family had emphysema but did not smoke.

After taking a careful history, your healthcare provider will perform a physical exam. They will listen to your lungs, but also look for other signs of emphysema, such as:

  • Abnormal breath sounds
  • A barrel chest: This refers to a rounding of the chest which may occur due to hyperinflation of the lungs.
  • Muscle wasting
  • Weight loss
  • The use of accessory muscles: When people are trying hard to breathe with lung diseases, it’s common to see a contraction of the neck muscles in an attempt to get more air.

Chest X-Ray

A chest X-ray is a radiographic examination of the lungs, heart, large arteries, ribs, and diaphragm. It can be performed in a radiology lab, healthcare provider’s office, or at your bedside if you are in the hospital.

Your healthcare provider will perform an initial chest X-ray to help them reach a diagnosis of emphysema, and then intermittently throughout your treatment to monitor your progress.

On an X-ray, emphysematous lungs look hyperlucent, with normal markings from blood vessels being less prominent. The diaphragms also appear flattened due to the hyperinflation of the lungs (which pushes down on the diaphragm). Unfortunately, changes on X-ray are not usually seen until the disease is quite extensive.

Often, a chest computed tomography (CT) scan will be performed, both to help with the diagnosis and to rule out other conditions, such as lung cancer, which may cause similar symptoms.

Pulmonary Function Tests

Pulmonary function tests are performed to assess lung function and determine the degree of damage to the lungs.

In patients with emphysema, there may be an increase in total lung capacity (the total amount of air you can breathe in after taking the deepest breath possible), but a decrease in vital capacity (the amount of air which can be inhaled or exhaled from the lungs) and forced expiratory volume (the maximum amount of air which can be exhaled, often in one second).

Diffusing capacity is another important measurement. The diffusing capacity for carbon monoxide is a measure of the conductance of gas transfer from inspired gas (carbon monoxide) to red blood cells.

Spirometry is a simple test that is often done to monitor emphysema. It measures the amount and how fast you can breathe in and breathe out.

Another test called lung plethysmography may also be done to determine your functional residual capacity—the amount of air left in your lungs after taking a normal breath. This is often used when the diagnosis is uncertain in order to distinguish obstructive vs. restrictive lung diseases.

All of these terms are confusing, but to understand your disease, it’s important for your healthcare provider to explain what they are and what they mean. Understanding where these numbers are at the time of diagnosis can help you understand if your symptoms are improving or worsening after treatment.

Arterial Blood Gases

Arterial blood gases (ABGs) are performed by taking blood from an artery, such as the radial artery in your wrist or your femoral artery in your groin.

This test measures the amount of oxygen and carbon dioxide in the blood, and also lets you and your healthcare provider know about the acidity (the pH) of your blood.

ABGs may be used to help diagnose the severity of your disease, as well as response to treatments.

Complete Blood Count

The complete blood count (CBC) is a blood test that can be used to help diagnose emphysema, as well as manage a variety of conditions.

A CBC is usually done during your initial physical examination and then periodically to monitor your condition.

A Word From Verywell

The importance of early diagnosis of emphysema cannot be overemphasized. While emphysema is not reversible by definition, early emphysema treatment and careful monitoring can help to slow the progression of the disease and improve your quality of life.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Goldklang M, Stockley R. Pathophysiology of emphysema and implicationsChronic Obstr Pulm Dis. 2016;3(1):454–458. doi:10.15326/jcopdf.3.1.2015.0175

  2. MedlinePlus. Emphysema.

  3. Sarkar M, Bhardwaz R, Madabhavi I, Modi M. Physical signs in patients with chronic obstructive pulmonary diseaseLung India. 2019;36(1):38–47. doi:10.4103/lungindia.lungindia_145_18

  4. Cleveland Clinic. Body plethysmography.

  5. Cukic V. The changes of arterial blood gases in COPD during four-year periodMed Arch. 2014;68(1):14–18. doi:10.5455/medarh.2014.68.14-18

  6. Xiong W, Xu M, Zhao Y, Wu X, Pudasaini B, Liu JM. Can we predict the prognosis of COPD with a routine blood test? Int J Chron Obstruct Pulmon Dis. 2017;12:615–625. doi:10.2147/COPD.S124041

Additional Reading

By Deborah Leader, RN
 Deborah Leader RN, PHN, is a registered nurse and medical writer who focuses on COPD.