B-Type Natriuretic Peptide: Biomarker of Persistent Pulmonary Hypertension of the Newborn?

Objective We assessed the utility of plasma B-type natriuretic peptide (BNP) in infants with persistent pulmonary hypertension of the newborn (PPHN) in the prediction of inhaled nitric oxide (iNO) requirement. Methods This prospective study involved neonates (gestational age ≥ 34 weeks) with PPHN and confirmatory echocardiographic findings. Plasma BNP was assayed once within 12 hours of meeting criteria for iNO requirements and twice every 24 to 48 hours thereafter. Results Infants requiring iNO (n = 14) had higher first BNP levels compared with others (n = 5) (455.5 ± 350.6 vs. 30.1 ± 25.3 ng/dL, p < 0.003). The sensitivity, specificity, positive and negative predictive values, and 95% confidence intervals (CI) for plasma BNP greater than 30 ng/dL to predict iNO requirement were 100 (85-100), 80 (37-80), 94 (80-94), and 100 (46-100)%, respectively. Corresponding values at a cut-off plasma BNP concentration greater than 85 ng/dL were 79 (62-79), 100 (53-100), 100 (79-100), and 63 (33-63)%, respectively. Conclusion BNP had excellent sensitivity and negative predictive value for iNO requirement and above 30 ng/dl maybe a useful prognostic biomarker in PPHN.