title: The relationship between BNP, NTproBNP and echocardiographic measurements of systemic blood flow in very preterm infants.
abstract: OBJECTIVE
  Preterm infants are at risk of circulatory compromise following birth. Functional neonatal echocardiography including superior vena cava (SVC) flow is increasingly used in neonatal medicine, and low SVC flow has been associated with adverse outcome. However, echocardiography is not readily available in many neonatal units and B-type natriuretic peptides (BNPs) may be useful in guiding further cardiovascular assessment. This study investigated the relationship between BNP, N-terminal pro-BNP (NTproBNP) and echocardiographic measurements of systemic blood flow in very preterm infants.
  
  
  METHODS
  This is a prospective observational study. Sixty preterm infants <32 weeks gestational age were included after the treating neonatologist had requested an echocardiogram for suspected cardiovascular compromise. BNP and NTproBNP were sampled just before the echocardiogram. Echocardiographic examination included fractional shortening (FS), SVC flow, left and right ventricular output (LVO and RVO). Statistical analysis included simple linear regression of BNP and NTproBNP with echocardiographic measures and multiple regression including potential confounding variables.
  
  
  RESULTS
  Mean (s.d.) gestational age at birth was 27(5) (2(1)) weeks, median (interquartile range, IQR) birth weight was 995 (845 to 1175) grams. Neither BNP nor NTproBNP correlated with SVC flow (BNP 95% confidence interval (CI) -0.0014 to 0.013, P=0.12; NTproBNP 95% CI -0.00069 to 0.01, P=0.085); LVO (BNP 95% CI -0.00078 to 0.0072, P=0.11; NTproBNP 95% CI -0.0034 to 0.0034, P=0.99); RVO (BNP 95% CI -0.00066 to 0.0058, P=0.12; NTproBNP 95% CI -0.0012 to 0.0044, P=0.25); or FS (BNP 95% CI -0.053 to 0.051, P=0.96; NTproBNP 95% CI -0.061 to 0.019, P=0.3). Multivariate linear regression did not significantly alter results.
  
  
  CONCLUSIONS
  In this cohort of very preterm infants, BNP and NTproBNP did not correlate with echocardiographic measurements of systemic blood flow within the first 72 h of life.
authors: 1] Department of Paediatrics, Mercy Hospital for Women, Melbourne, VIC, Australia [2] Neonatal and Paediatric Intensive Care Unit, Children's Hospital Lucerne, Lucerne, Switzerland.
authors: K
authors: K
authors: König
authors: Department of Paediatrics, Mercy Hospital for Women, Melbourne, VIC, Australia.
authors: K J
authors: KJ
authors: Guy
authors: Department of Paediatrics, Mercy Hospital for Women, Melbourne, VIC, Australia.
authors: G
authors: G
authors: Walsh
authors: Department of Paediatrics, Mercy Hospital for Women, Melbourne, VIC, Australia.
authors: S M
authors: SM
authors: Drew
authors: Department of Paediatrics, Mercy Hospital for Women, Melbourne, VIC, Australia.
authors: A
authors: A
authors: Watkins
authors: Department of Paediatrics, Mercy Hospital for Women, Melbourne, VIC, Australia.
authors: C P
authors: CP
authors: Barfield
mesh_terms: D001775:Blood Circulation / Q000502:physiology*; D004452:Echocardiography / Q000379:methods; D005260:Female; D006801:Humans; D062071:Infant, Extremely Premature / Q000502:physiology*; D007231:Infant, Newborn; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011446:Prospective Studies; D014683:Vena Cava, Superior / Q000000981:diagnostic imaging / Q000502:physiology; D016277:Ventricular Function, Left / Q000502:physiology
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain