Correlation Between Lung Ultrasonography Score and Oxygenation Indices in Neonates with Respiratory Distress

Abstract

Introduction

Neonatal respiratory distress has long remained a significant problem in neonatal intensive care units (NICUs) worldwide. Traditional methods of assessment include chest X-ray (CXR) and blood gas analysis, with their inherent disadvantages, such as radiation exposure and delayed report generation. Lung ultrasonography score (LUSs) has emerged as a useful bedside, non-invasive tool to assess neonatal lung function.

Objectives

To assess the diagnostic value of LUSs in neonates with respiratory distress in terms of oxygenation level and correlation between LUSs and key indices of oxygenation, such as the arterial to alveolar (a/A) ratio, oxygenation index (OI), and partial pressure of oxygen (PaO₂).

Methods

A prospective observational study was carried out on neonates admitted to the NICU with respiratory distress. LUS and oxygenation indices, which included the a/A ratio, OI, and PaO₂, were documented at admission and after 12 h. Pearson’s correlation analysis was performed to find out the associations.

Results

Among the total of 75 neonates, 34 (45.3%) were term, 21 (28%) were preterm, and 20 (26.7%) were late preterm. The most common diagnosis among neonates with respiratory distress was respiratory distress syndrome (RDS) in 54 (72%), followed by transient tachypnea of the newborn (TTNB) in 16 (21.3%), meconium aspiration syndrome (MAS) in 3 (4%), and congenital pneumonia in 2 (2.7%). LUSs showed a good correlation with oxygenation indices, including significant inversion with the ratio a/A (r = −0.56, P < .001) and a positive correlation with OI (r = 0.69, P < .001). Subgroup analysis indicated a statistically significant moderate negative correlation between LUS and OI in preterm neonates (r = −0.437, P = .048), whereas such a correlation was not observed in term or late-preterm groups.

Conclusion

A strong correlation between LUSs and oxygenation indices in neonates with respiratory distress, particularly in preterm infants. LUS emerges as a reliable bedside tool as a dynamic, real-time marker of respiratory compromise and recovery.