HIGH ENDOTHELIN-1 IN THE AIRWAYS OF PRETERM INFANTS IS ASSOCIATED WITH LESS SEVERE RESPIRATORY-DISTRESS DURING THE EARLY POSTNATAL-PERIOD

Objective. To study the relationship between endothelin-1 (ET-1) in th e airways and respiratory distress in preterm infants. Methods. ET-1 w as determined in 60 tracheal aspirates from 11 preterm intubated infan ts (gestational age 28.0 +/- 2.5 weeks) during the first week of life. Results. The concentration of ET-1 of the aspirates was 6 to 2760 pg/ mL (median 293 pg/mL). Negative correlations existed between mean log ET-1 and mean airway pressure (R(2) =.812) and fraction of inspired ox ygen (R(2) =.591), whereas a positive correlation was found between th e arteriolar/alveolar oxygenation ratio within 3 hours of birth and me an log ET-1 on the first day (R(2) =.555). Conclusion. The association of high ET-1 in the airways with less severe respiratory distress in the early postnatal period may be attributable to effects of ET-1 on s urfactant secretion or development of airway epithelium.