Association of Lung Ultrasound Scores With Different Modes of Respiratory Support and Clinical Outcomes: An Observational Study in a Tertiary Care Neonatal Unit.

BACKGROUND

Lung ultrasound (LUS) is an evolving point-of-care tool in the neonatal intensive care unit. LUS score has been evaluated in adults as well as in neonates to characterize and diagnose various respiratory conditions. Recently, the LUS score has been evaluated for predicting clinical respiratory outcomes in neonates.

OBJECTIVE

To assess the association between LUS score and various modes of respiratory support and clinical outcomes among neonates presenting with respiratory distress.

METHODS

In this prospective, cross-sectional, observational study done in a tertiary care neonatal unit, the LUS score was calculated within three hours of receiving respiratory support. Subsequently, the LUS score was assigned with each escalation and de-escalation of respiratory support. Maximum LUS scores for each clinical outcome were also recorded. Inter-rater agreement was determined with the intraclass correlation coefficient.

RESULT

A total of 162 LUS scans were performed in 65 babies with a mean gestation of 32.4 ± 3.7 weeks and median (IQR) birth weight of 1480 (1130-2000) grams. The LUS scores (median (IQR)) of babies on continuous positive airway pressure (CPAP), noninvasive positive pressure ventilation (NIPPV), and mechanical ventilation (MV) were 4 (3-6.5), 9 (8-11), and 12 (11-13.5), respectively (p-value < 0.001). The difference in maximum median LUS scores between different clinical outcomes was statistically significant, with a p-value < 0.001. LUS score had an excellent inter-rater agreement (intraclass correlation coefficient = 0.998; p-value < 0.001).

CONCLUSION

There is an association between LUS score and different modes of respiratory support with scores increasing as the level of support increased. LUS score was also found to be related with clinical outcomes like death, extubation failure, and recovery, which could help in predicting the prognosis.