Your doctor will diagnose ARDS based on your medical history, a physical exam, and test results.
Your doctor will ask whether you have or have recently had conditions that could lead to ARDS. For a list of these conditions, go to "Who Is at Risk for ARDS?"
Your doctor also will ask whether you have heart problems, such as heart failure. Heart failure can cause fluid to build up in your lungs.
ARDS may cause abnormal breathing sounds, such as crackling. Your doctor will listen to your lungs with a stethoscope to hear these sounds.
He or she also will listen to your heart and look for signs of extra fluid in other parts of your body. Extra fluid may mean you have heart or kidney problems.
Your doctor will look for a bluish color on your skin and lips. A bluish color means your blood has a low level of oxygen. This is a possible sign of ARDS.
You may have ARDS or another condition that causes similar symptoms. To find out, your doctor may recommend one or more of the following tests.
The first tests done are:
- An arterial blood gas test. This blood test measures the oxygen level in your blood using a sample of blood taken from an artery. A low blood oxygen level might be a sign of ARDS.
- Chest x ray. This test creates pictures of the structures in your chest, such as your heart, lungs, and blood vessels. A chest x ray can show whether you have extra fluid in your lungs.
- Blood tests, such as a complete blood count, blood chemistries, and blood cultures. These tests help find the cause of ARDS, such as an infection.
- A sputum culture. This test is used to study the spit you've coughed up from your lungs. A sputum culture can help find the cause of an infection.
Other tests used to diagnose ARDS include:
- Chest computed tomography (to-MOG-rah-fee) scan, or chest CT scan. This test uses a computer to create detailed pictures of your lungs. A chest CT scan may show lung problems, such as fluid in the lungs, signs of pneumonia, or a tumor.
- Heart tests that look for signs of heart failure. Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. This condition can cause fluid to build up in your lungs.