title: Umbilical cord blood and neonatal endothelin-1 levels in preterm newborns with and without respiratory distress syndrome.
abstract: Increased pulmonary vascular resistance in preterm newborn infants with respiratory distress syndrome is suggested, and endothelin-1 plays an important role in pulmonary vascular reactivity in newborns. We determined umbilical cord blood and neonatal (second sample) levels of endothelin-1 in 18 preterm newborns with respiratory distress syndrome who had no clinical or echocardiographic diagnosis of pulmonary hypertension and 22 without respiratory distress syndrome (gestational ages: 31.4 +/- 1.6 and 29.3 +/- 2.3 weeks, respectively). Umbilical cord blood and a second blood sample taken 18 to 40 h after birth were used for endothelin-1 determination by enzyme immunoassay. Median umbilical cord blood endothelin-1 levels were similar in both groups (control: 10.9 and respiratory distress syndrome: 11.4 pg/mL) and were significantly higher than in the second sample (control: 1.7 pg/mL and respiratory distress syndrome: 3.5 pg/mL, P < 0.001 for both groups). Median endothelin-1 levels in the second sample were significantly higher in children with respiratory distress syndrome than in control infants (P < 0.001). There were significant positive correlations between second sample endothelin-1 and Score for Neonatal Acute Physiology and Perinatal Extension II (r = 0.36, P = 0.02), and duration of mechanical ventilation (r = 0.64, P = 0.02). A slower decline of endothelin-1 from birth to 40 h of life was observed in newborns with respiratory distress syndrome when compared to controls. A significant correlation between neonatal endothelin-1 levels and some illness-severity signs suggests that endothelin-1 plays a role in the natural course of respiratory distress syndrome in preterm newborns.
authors.affiliation: Hospital de Clínicas de Porto Alegre, Departamento de Pediatria, Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: A C W
authors.initials: AC
authors.lastname: Benjamin
authors.forename: R C
authors.initials: RC
authors.lastname: Silveira
authors.forename: R S
authors.initials: RS
authors.lastname: Procianoy
mesh_terms: D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D019332:Endothelin-1 / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D012127:Respiratory Distress Syndrome, Newborn / Q000097:blood*
chemical_list: D015415:Biomarkers; D019332:Endothelin-1