Pulmonary function in chronic respiratory failure of infancy.

We studied pulmonary function in 7 infants age 3-16 months who were dependent upon mechanical ventilation due to bronchopulmonary dysplasia (BPD). Raised lower expiratory airway resistance (RAe), low dynamic lung compliance (CL) and rapid respiratory frequency (f) characterized the breathing pattern in these infants. End-tidal carbon dioxide tension (PECO2) was elevated in spite of abnormally high minute ventilation (VE). One infant died of respiratory failure, 1 died of sepsis and 1 of an occluded tracheostomy after discharge from the hospital. Another infant still requires mechanical ventilation at age 18 months. Recovery from chronic respiratory failure in 4 infants occurred between age 1.2-2.5 years. The infants recovered concomitant with the ability to sustain a high VE in spite of persistently elevated RA and low CL. All of the surviving infants, although developmentally delayed, have the potential for home care with further growth and development.