Sonographic evaluation of lungs and diaphragm as a predictor for extubation failure in early preterm neonates: a prospective diagnostic accuracy study.

Lung and diaphragm ultrasound has been shown to reliably predict extubation failure (EF) in adults and children; however, its role in preterm infants remains unclear. This study aimed to evaluate the diagnostic accuracy of lung ultrasound (LUS) aeration score and diaphragmatic indices for predicting EF in early preterm neonates. In this prospective diagnostic accuracy study, preterm infants < 34 weeks intubated for more than 24 h were enrolled. Lung and diaphragm ultrasound was done 1 h prior to extubation. LUS scoring was performed by two independent blinded assessors. The primary outcome was the diagnostic accuracy of lung and diaphragm ultrasound for predicting EF within 72 h. We enrolled 45 infants, of whom 20 (44%) had EF. Gestation and birth weight were significantly lower in the EF group. The median (IQR) LUS aeration score was significantly higher in the EF group, compared to the success group [8.75 (5-12) vs. 4 (0-7); p < 0.001]. There were no significant differences in diaphragmatic excursion or diaphragmatic thickness fraction between the two groups. On logistic regression, LUS remained an independent predictor of EF (odds ratio 5.40, 95% CI 1.57-18.50; p = 0.007). The area under the ROC curve was 0.97 (95% CI 0.94-1.00) for LUS aeration score, with an optimal cut-off score of ≥ 7 having 80% sensitivity and 96% specificity in predicting EF.

conclusionsIn preterm infants < 34 weeks, LUS demonstrated reliable accuracy in predicting EF within 72 h. Measurements of diaphragmatic indices were feasible but did not prove to be good predictors of EF. WHAT IS KNOWN: • The incidence of extubation failure in preterm infants remains substantial, with reported rates varying between 10% and 80%. • There are no reliable tools currently that can predict extubation failure accurately in preterm neonates. WHAT IS NEW: • In preterm infants 34 weeks, lung ultrasound demonstrated reliable accuracy in predicting extubation failure within 72 hours. • Measurements of diaphragmatic indices were feasible on ultrasound but did not prove good predictors of extubation failure.