Lung Ultrasound Score Predicts the Extravascular Lung Water Content in Low-Birth-Weight Neonates with Patent Ductus Arteriosus

Abstract

BACKGROUND Patent ductus arteriosus (PDA) is a common congenital cardiac abnormality in premature infants. In low-birth-weight infants weighing less than 2500 g, if the PDA continues to open, abnormal circulation hemodynamics and pulmonary edema may occur. This study aimed to investigate the role of lung ultrasound score in the assessment of pulmonary edema in low-weight neonates with PDA. MATERIAL AND METHODS Two hundred and twenty-one neonates with low birth weight were selected as the subjects, children with PDA as the observation group, and children with closed ductus arteriosus as the control group. On the fourth postnatal day, lung ultrasound examination and 6-segment lung ultrasound scoring were performed. RESULTS All 221 infants (94 in the observation group, 127 controls) underwent ultrasound examinations of the lungs. Intergroup differences in gestational age, birth weight, length of hospital stay, and left ventricular ejection fraction were not statistically significant. There was a significant difference in lung ultrasound score (t=0.005, P=0.000) and aortic root ratio to left atrial (t=0.085, P=0.000), which was negatively correlated with gestational age (r=-0.235, P=0.000) and positively correlated with PDA diameter (r=0.261, P=0.011). CONCLUSIONS Low-birth-weight children often have PDA. Its continued opening changes the circulation hemodynamics in children. Lung ultrasound score can semi-quantitatively evaluate the extravascular lung water content, identifying the need to intervene and follow up the hemodynamic significance of PDA over time.

Figure 1

(A) Line A, ultrasound score: 0 point. (B) Irregular line B; ultrasound score: 1 point. (C) Diffuse fusion line B; ultrasound score: 2 points. (D) Local solid change, ultrasound score: 3 points.

Figure 2

ROC curve for assessing whether the pulmonary artery catheter is closed with the double lung score. The area under the ROC curve is 0.668. When the cut-off value of the lung score is 9.5, the sensitivity of the predicted PDA is 50% and the specificity is 76.4%.