The Utility of Lung Ultrasound Scoring in Predicting Post-Extubation Respiratory Support after Congenital Heart Surgery.

Abstract

Objectives: Lung ultrasound (LU) is effective in diagnosing the accumulation of extravascular lung water and assessing real-time fluid status in infants following congenital cardiac surgery with cardiopulmonary bypass. This study evaluated whether LU can be used as a prognostic marker for changes in noninvasive respiratory support after extubation.

Methods: Infants with congenital heart disease (CHD) <1 year of age requiring mechanical ventilation for more than 24 hours postoperatively were included. Using a linear probe, 3 scan fields from each hemithorax were assessed for B-lines and consolidations, with scores ranging from 0 to 3 assigned per area. LU scores were rated then by 4 independent operators. After extubation, patients were monitored for respiratory support modifications over the following 48 hours and were divided into 3 subgroups: steady state, escalation, and de-escalation, accordingly.

Results: In this single-center observational pilot study, a total of 30 patients with a median age of 116 (interquartile range: 17-196) days were included in the prospective analysis between July 2022 and December 2023. LU scores differed significantly among groups: 3.47 ± 2.3 (steady state), 6.14 ± 2.55 (escalation), and 1.63 ± 1.41 (de-escalation), P = .002. ROC analysis identified a cut-off score of ≥5 as predictive of escalation risk with a sensitivity of 86% and specificity of 83%. A score <2 suggested potential for de-escalation within 48 hours, with a sensitivity of 75% and specificity of 73%.

Conclusions: LU scoring may be a valuable tool for optimizing ventilator weaning and post-extubation respiratory strategies in infants undergoing congenital cardiac surgery. Further studies are warranted to validate these findings.