Lung Function Testing, also referred to as Pulmonary Function Testing, is measured routinely at SEC Lung using Total Body Plethysmography, the most accurate method for measuring common lung functions. Several different aspects of lung function are measured:
- Spirometry: You are instructed to take a full deep breath, then exhale as forcefully and quickly as possible into a tube until your airflow stops, generally 6-12 seconds. The volume of air exhaled is measured over time, and the two primary values we examine are (a) volume of air expelled in the first second of the exhalation, called the Forced Expiratory Volume 1 second [FEV1], and (b) volume of air expelled over the entire maneuver [Forced Vital Capacity]. This portion of Lung Function testing is especially important in evaluation of individuals with known or suspected COPD and asthma.
- Lung Volumes: This portion of the lung function testing measures the volume of your lungs at different phases of breathing. The two most important measurements are (a) Total Lung Capacity, the volume of air in the lungs after taking the deepest breath possible, and (b) Residual Volume, the amount of air remaining in the lungs after blowing out all the air possible with a long forceful expiration. These values are particularly important for the evaluation of lung conditions that can cause limits in lung expansion, such as Pulmonary Fibrosis.
- DLCO: The letters are an abbreviation for Diffusion in Lung of CO [carbon monoxide]. In this test, you take a full breath of a medical gas containing a trace amount of carbon monoxide, your breath held for 10 seconds, then quickly exhaled into a bag from which the amount of carbon monoxide is measured. Our instruments can measure the amount of carbon monoxide that passes into the bloodstream which approximates the passage of oxygen. In this way, we can determine the efficiency of oxygen transfer from lungs into the blood.
- 6 Minute Walk Test: This test does not measure lung function with a machine, but as the name implies, measures the distance you can walk in 6 minutes – and we also measure your vital signs including blood oxygen level at the start and end of the walking. This simple test provides valuable information about exercise capacity, and whether limitations are caused by a drop in oxygen levels.