BRONCHOALVEOLAR OXYRADICAL INFLAMMATORY ELEMENTS HERALD BRONCHOPULMONARY DYSPLASIA

Objectives: To quantify oxyradical inflammatory markers in serial endo tracheal tube aspirates obtained from premature neonates at risk for d eveloping bronchopulmonary dysplasia, and to correlate these parameter s with clinical manifestations of the disease. Design: Prospective coh ort study. Setting: Tertiary neonatal intensive care unit. Patients: T wenty-eight intubated, premature infants, with 15 infants displaying s imple respiratory distress syndrome and 13 infants eventually developi ng bronchopulmonary dysplasia. Interventions: Endotracheal tube aspira tes were collected and clinical severity scores were calculated longit udinally from an inception cohort during the first week of life. Diagn osis of bronchopulmonary dysplasia by standard criteria was recorded a t 30 days of life. Various biochemical analyses related to pulmonary o xyradical stress were determined on endotracheal tube aspirates and we re normalized according to the magnitude of serum/aspirate urea ratios . The demographic, illness severity, and biochemical characteristics o f infants with simple respiratory distress syndrome and those characte ristics of infants developing bronchopulmonary dysplasia were evaluate d by masked comparison. Measurements and Main Results: Populations of respiratory distress syndrome and bronchopulmonary dysplasia infants c ould be differentiated during the first week of life by means of the f ollowing parameters: gestational age; birth weight; Score of Neonatal Acute Physiology; Neonatal Therapeutic Intervention Scoring System; ep ithelial lining fluid leukocytes; elastase; myeloperoxidase; xanthine oxidase and catalase enzyme activities; and total sulfhydryls. Conclus ions: Infants with simple respiratory distress syndrome could be segre gated from those infants who developed bronchopulmonary dysplasia by t he magnitude of the epithelial lining fluid oxyradical inflammation ma rkers. While infants developing bronchopulmonary dysplasia typically e xhibited increased concentrations of these markers during the first we ek of life, those infants with simple respiratory distress syndrome di splayed low, uniform, or decreasing values of these markers over this interval. Infants developing bronchopulmonary dysplasia demonstrate an early pulmonary inflammatory response, and one key aspect of this res ponse involves various oxyradical generating systems.