Maintain Your Health

Every doctor will have a different strategy to monitor pulmonary fibrosis. Usually, a doctor collects a variety of types of information to help them determine if a patient's disease is stable or changing. Your doctor may use a combination of the symptoms you are experiencing, pulmonary function tests, walking tests, and high-resolution computed tomography (HRCT) scans to gather information about the state of your disease. A doctor may also need to order other tests to find out how your pulmonary fibrosis is affecting you.

One of the most important signs that something has changed in your lungs is a change in the amount of breathlessness you experience while exerting yourself. A new or worsening cough can also be a sign that something in the lungs has changed. If you experience one of these problems, your doctor will first try to determine whether your symptoms are due to progression (new scar tissue in the lungs) or something else (an infection, a blood clot, a heart problem, etc.).

Doctors routinely order one or more of the following pulmonary function tests (PFTs) to monitor your PF.

Spirometry is performed by taking a deep breath in and then blowing out as hard and fast as you can through a mouthpiece connected to a machine. Spirometry measures how much air you can blow out (called the forced vital capacity or FVC) and how fast the air comes out. For most people with PF, monitoring the FVC can tell your doctor whether your disease is stable or progressing and whether your disease is mild, moderate, or severe. It’s easiest to track your FVC expressed as a percentage of normal. Normal is between 80 and 100% of the predicted value (which is based on your age, gender, height, and ethnicity). As more scar tissue develops in your lungs, your FVC will go down.

Lung volume measurements can tell how much air your lungs can hold. Just like FVC, the results are expressed as a percentage of normal. The result that is usually tracked is called the total lung capacity (TLC). Normal is between 80 and 100% of the predicted value for age, gender, height, and ethnicity and decreases as more scar tissue develops in the lungs. This test is not performed as frequently as spirometry as it is more costly and time consuming and provides similar information as spirometry.

Diffusing capacity (DLCO) measures how easy it is for gases (like oxygen) to move from your lungs into your bloodstream. Scar tissue makes the transfer of oxygen less efficient. Just like FVC and TLC, DLCO is expressed as a percentage of the normal value and goes down as more scar tissue develops in the lungs. Do not be surprised by a DLCO that is much lower than the FVC or TLC— that is expected in people living with pulmonary fibrosis.

Doctors use a walking test to see how far you can walk (usually in six minutes) and how low your oxygen levels go when you walk. Sometimes the test is performed when you are using oxygen, and sometimes it is performed without oxygen. Doctors will compare your walking distance and your oxygen levels to your results from previous visits to determine whether your lung disease has progressed. Doctors often also use this test to determine whether or not you need to use supplemental oxygen while exerting yourself in your home and outdoors.

A doctor will use a special kind of X-ray of the chest, called a high-resolution computed tomography (HRCT) scan, so that they can see what your lung tissue looks like. HRCT scans give a close-up view of the lungs, providing more detail than routine CT scans (also known as CAT scans). An HRCT scan is a necessary test to diagnose PF. When repeated later on, comparing the change between two HRCT scans can tell your doctor if there is more scarring in the lungs. Some doctors perform multiple HRCT scans each year, some once per year, and some only when there is a change in your symptoms, spirometry, or walking test results.

There are other tests doctors sometimes use to better understand your disease and its impact on your health, including arterial blood gas testing, cardiopulmonary exercise testing, and an echocardiogram. An arterial blood gas directly measures the amount of oxygen and carbon dioxide in your bloodstream and helps your doctor understand how well or poorly your lungs are functioning. Some forms of pulmonary fibrosis may also affect your heart. To investigate this possibility, your doctor might order an echocardiogram (or ultrasound) of the heart or a cardiopulmonary exercise test.