BRONCHIAL HYPERREACTIVITY IN LONG TERM SURVIVORS OF THE NEONATAL RESPIRATORY DISTRESS SYNDROME (RDS)

Recent reports have shown residual bronchial hyperreactivity in long term survivors of bronchopulmonary dysplasia and Wilson Mikity syndromes. Our aim was to extend these studies to survivors of uncomplicated RDS. The study group consisted of 7 males and 7 females born between 1974 and 1976. Measurements of static and dynamic lung volumes were made and a methacholine challenge (MCH) was performed on each child. Expiratory flow rates for the total group were statistically significantly reduced (p < .01). Pulmonary function was significantly lower in the MCH positive group when compared with the MCH negative group. There was a positive correlation between duration of IPPB and log dose MCH, R = -0.78, p = 0.02. There was no significant differences between either group for age, sex, height, weight or age at onset of mechanical ventilation. The MCH positive group had received a significantly longer duration of IPPB during the course of the neonatal respiratory failure. Thus, even in survivors of RDS without major sequelae, there is evidence of residual airway hyperreactivity and abnormal pulmonary function. We consider this increased airway reactivity and reduced pulmonary function to be one of the risk factors in the development of chronic obstructive pulmonary disease later in life.