Pulmonary function testing (PFT) in children plays an important role in the evaluation of the child with known or suspected respiratory disease. It allows for assessment of normal lung and airway growth, the natural history of diseases (eg, bronchopulmonary dysplasia, cystic fibrosis), the site and type of obstruction (central versus peripheral, intrathoracic versus extrathoracic, fixed versus variable), the impact of therapies (eg, bronchodilators, glucocorticoids, diuretics, mucolytics), and the degree of impairment. PFT can also be used to assess the impact of environmental factors (eg, tobacco smoke, toxic gases) and the degree of airway reactivity. In addition, PFT can aid in preoperative assessment of the child with chronic lung disease or neuromuscular weakness. Furthermore, measures of lung function (eg, forced expiratory volume in one second [FEV1]) have prognostic value with regards to mortality in some diseases like cystic fibrosis (CF).
PFT is recommended by the National Asthma Education and Prevention Program (NAEPP) and the Global Initiative for Asthma (GINA) in the assessment and long-term monitoring of patients with asthma . There is a growing need for PFT as the incidence of childhood asthma continues to rise. The development of compact and affordable instruments also enables pediatric lung function testing in the primary care setting.
A basic approach to PFT for the primary care provider is presented here. The goal is to encourage pediatricians to obtain PFT to diagnose and monitor the pathophysiologic aspects of their patients' respiratory conditions, thereby improving management.
Conventional tests that are frequently performed in the evaluation of pediatric respiratory conditions include measurements that identify: