Right Pulmonary Artery Measurements in Term and Preterm Neonates during the Early Newborn Period: Hemodynamic Correlation and Clinical Significance

Abstract

AbstractRight pulmonary artery (rPa) diameter was measured during the first hour of life, then during the next 23 hours, at 72 hours and at 120 hours in 62 normal term and 14 normal preterm neonates by M‐mode echocardiography via the suprasternal notch. Left atrium (LA) and aortic (Ao) diameters were likewise determined from the standard parasternal view. Comparison was also made with rPA values of 34 patients with patent ductus arteriosus (26), persistent fetal circulation (6) and cyanotic congenital heart disease (2).In normal term babies, the mean rPA size changed significantly during the 4 periods of examination with diameters of 4.6 mm, 5.5mm, 5.2mm and 4.7 mm respectively. Among preterm babies, mean rPA diameter at 24 hours was 3.8 mm, at 72 hours, 3.8 mm, and at 120 hours, 3.3 mm. unlike those in term babies, the changes in preterm babies were not significant. LA dimensions and LA/Ao ratio were more variable. Furthermore, rPA measurements reliably differentiated clinical conditions with increased or decreased pulmonary blood flow. Thus, our data confirm the significance of rPA measurement as it closely correlates with the hemodynamic changes in the early neonatal period in normal and abnormal term and preterm babies.