HFCC is an FDA (1988 under Class II 510K) approved device/modality of chest physiotherapy which has been utilized in patients with mucus hypersecretion, atelectasis and pneumonia. There is a paucity of pediatric studies. A comparative retrospective/prospective data analysis on exacerbations and hospitalizations in medically fragile (profoundly disabled) children using outpatient HFCC showed that use of this therapy reduced days of hospitalization for pulmonary exacerbations. Long term use in quadriplegic children reduced pulmonary secretions, incidence of pneumonia, and number of hospitalizations. In the pediatric cystic fibrosis population, there was improvement of lung function during hospitalization and long term decrease in progression of lung disease. Furthermore, in patients with mild to moderate asthma, there was no decline in lung function with the use of beta agonist and HFCC versus beta agonist alone indicating good tolerance and safety.