Spirometry is one of the most common pulmonary lung function tests. It is used to test for a variety of lung problems and to determine the effectiveness of treatment. The patient takes a deep breath and breathes out with force into a spirometer to the best of their ability. The spirometer measures both the amount of air expelled and how quickly the air was expelled from the lungs.New research brings to light some common problems with a spirometry test.
It is widely assumed that accuracy is guaranteed by frequent calibrations. However, researchers say errors frequently occur during the test that can lead to inaccurate results. They say one common error happens when the machine measures the zero level or no airflow incorrectly. Another common error can occur when the sensor is obstructed by condensation of water vapor, mucus, or the subject's fingers.
Researchers say these two problems are especially dangerous because the high values they produce replace accurate but lower values recorded during testing, leading the technician to believe the patient's lung function is better than it actually is.
Thus researchers say that those who conduct spirometry need to be aware of these possible errors.