We evaluated eight infants with bronchopulmonary dysplasia (BPD) at ages from 2 to 13 months who had repeated episodes of clinical respiratory deterioration associated with agitation. These episodes limited further weaning from ventilation or necessitated recurrent intubation and reinstitution of ventilation. All infants underwent spirometric evaluation and six also had endoscopic examination during simulated agitation episodes (elicited by toe pinching). All babies were found to have a very prolonged near zero expiratory airflow pattern, accompanied by vigorous diaphragmatic and abdominal muscle activity and rapid development of hypoxia. Six patients had endoscopically documented tracheal collapse under the same simulated circumstances. The episodes ceased with calming or sedation of the infants.