Clinical significance of plasma N-terminal pro- B-type natriuretic peptide in respiratory distress syndrome of the preterm neonate.

Abstract

Plasma brain-type natriuretic peptide (BNP) is secreted by cardiac myocytes in response to pressure or volume overload. Recently, an assay to measure the N-terminal segment of the pro-hormone (NT-pro-BNP) was developed.(1) To determine the plasma levels of NT-pro-BNP in premature neonates without congenital heart disease; (2) to determine the relationship between the severity of respiratory distress syndrome (RDS) and plasma levels of NT-pro-BNP.Plasma levels of NT-pro-BNP were measured in premature neonates (<34 wks gestation) at 24 hours, and days 7 and 21 of life. Levels of NT-pro-BNP were compared between neonates with and without RDS.45 neonates, 25/20 (F/M), gestational age 30 (25-33) weeks, birthweight 1290 (500-2220) g. RDS occurred in 21 (47%) neonates: RDS I (mild) = 7; RDS II (moderate) = 10; RDS III (severe) = 4. Comparative analysis revealed a significant increase in plasma level of NT pro-BNP at 24 hours (p = 0,001) and day 7 (p = 0,015) of life in patients with RDS. Plasmatic levels of NT-pro-BNP at 24 hours of age were significantly increased in patients with severe RDS than in patients with mild (p < 0,001) or moderate RDS (p < 0,002), after adjustment for gestational age and birthweight.plasma levels of NT-pro-BNP are directly related to increasing severity of RDS in neonates, suggesting a close relation to the functional impairment of pulmonary haemodynamical changes.