The therapeutic effects of dexamethasone in bronchopulmonary dysplasia

ABSTRACT

We observed clinical features of 18 bronchopulmonary dysplasia (BPD) patients who were admitted to the neonatal intensive care unit in the Severance Hospital of Yonsel University College of Medicine from January 1. 1987 to June 30. 1991. Eight patients in whom ventilator settings were unchanged for more than 5 days because of lack of improvement in pulmonary function. The effects of dexamethasone in ventilator-dependent were included in the short-term dexamethasone therapy. 1) Eighteen BPD patients consisted of 15 premature infants (83%), 1 full-term infant, and 2 post-term infants, The mean gestational age of the patients were 30 weeks and the mean birth weight was 1,420gm. And there were 13 male and 5 female infants. 2) The underlying conditions which necessitated ventilatory support support were hyaline membrane disease in 13 patients (72%), apnea in 2 (11%), and meconium aspiration syndrome in 3. There patients with meconium aspiration syndrome were either full-term or post-term infants, of whom 2 had neonatal persistent pulmonary hypertension. 3) The mean age at the start of ventilator care was 8 hours and the mean PIP was 32 cm H2O. The mean duration of ventilator care of oxygen therapy and of high O2 requirement (FiO2>0.8) were 39 days, 75 days and 20 days, respectively. 4) Patent ductus arteriosus developed in 8 patients during mechanical ventilation, but they were all closed with the use of mefenamic acid, There were also 4 cases of pneumothorax, 2 cases of pulmonary parenchymal emphysema, and 1 case each of pneumomediastinum and pneumoperitoneum. 5) The mean gestational age of the dexamethasone-treated group was 30 weeks and the mean birth weight was 1,320gm, The mean age at which dexamethasone therapy was started was 39 days after birth, and in only 3.3 days 6 patients were successfully weaned from ventilator, In 5 cases the first trial of dexamethasone therapy was enough but the rest needed the 2nd trial for ventilator weaning. 6) In 6 BPD patient who were weaned from the ventilator after dexamethasone therapy, there were significant decreases in MAP (11.1 vs 8.0 cmH2O), and FiO2 (0.73 vs 0.61), but a significant increase in the urine output (2.56 vs 3.7ml/kg/hr) for the pretreatment (5 days prior to therapy) versus posttreatment period (first day of therapy). 7) The complications of dexamethasone treatment were transient hypertension and hyperglycemia in 3 patients, and systemic candidiasis and gastrointestinal bleeding in 2 patients who failed to be weaned after dexamethasone therapy. Our results suggest that the short-term dexamethasone therapy in bronchopulmonary dysplasia patients who are dependent on mechanical ventilation enables weaning in a short period of time. The inspiratory oxygen concentration and the mean airway pressure may be decreased and the urine output may be increased from the first day of medication, improves pulmonary function and decreases pulmonary interstitial edema.