Spirometry is perhaps the most technically and physically demanding.
The patient is required to inhale as fully as possible, exhale with as much force as possible, and continue their expiratory effort until they empty their lungs as completely as possible or are unable to continue.
The forced expiratory flow at any given lung volume is reduced.
Airway obstruction is the most common cause of reduction in FEV does not indicate the patient will not benefit clinically from bronchodilator therapy.
A significant increase in the inspiratory capacity (IC) and/or vital capacity (VC) after bronchodilator therapy can occur even when the FEV Spirometry is used to establish baseline lung function, evaluate dyspnea, detect pulmonary disease, monitor effects of therapies used to treat respiratory disease, evaluate respiratory impairment, evaluate operative risk, and perform surveillance for occupational-related lung disease.
Readers are directed to Spirometry Quality Assurance: Common Errors and Their Impact on Test Results.
A booklet can also be obtained from the Department of Health and Human Services.
Example of an acceptable spirometry testing session showing evidence 3 efforts that show evidence of an explosive start of forced exhalation that continues until empty and good repeatability of forced vital capacity (FVC) and forced expiratory volume in the first second of the forceful exhalation (FEV1), which usually indicates all efforts started from full inflation.
Comprehensive treatment of technical acceptability of spirometry test results is beyond the scope of this review.
The performance standards for spirometry are summarized below.
The comments of the technologist administering the test can assist the interpreting physician in determining if results of a testing session that fail to meet some of the standards can still provide clinically useful data.
Two choices are available with respect to bronchodilator and medication use prior to testing.