Predicting extubation failure in preterm infants using lung ultrasound: a diagnostic accuracy study

Abstract

ObjectiveTo determine the accuracy of pre-extubation lung ultrasound (LUS) to predict reintubation in preterm infants born <32 weeks’ gestation.DesignProspective diagnostic accuracy study.SettingTwo neonatal intensive care units.MethodsAnterior and lateral LUS was performed pre-extubation. The primary outcome was the accuracy of LUS scores (range 0–24) to predict reintubation within 72 hours. Secondary outcomes were accuracy in predicting (1) reintubation within 7 days, (2) reintubation stratified by postnatal age and (3) accuracy of lateral imaging only (range 0–12). Pre-specified subgroup analyses were performed in extremely preterm infants born <28 weeks’ gestation. Cut-off scores, sensitivities and specificities were calculated using receiver operating characteristic analysis and reported as area under the curves (AUCs).ResultsOne hundred preterm infants with a mean (SD) gestational age of 27.4 (2.2) weeks and birth weight of 1059 (354) g were studied. Thirteen were subsequently reintubated. The AUC (95% CI) of the pre-extubation LUS score for predicting reintubation was 0.63 (0.45–0.80). Accuracy was greater in extremely preterm infants: AUC 0.70 (0.52–0.87) and excellent in infants who were <72 hours of age at the time of extubation: AUC 0.90 (0.77–1.00). Accuracy was poor in infants who were >7 days of age. Lateral imaging alone demonstrated similar accuracy to scanning anterior and lateral regions.ConclusionsIn contrast to previous studies, LUS was not a strong predictor of reintubation in preterm infants. Accuracy is increased in extremely preterm infants. Future research should focus on infants at highest risk of extubation failure and consider simpler imaging protocols.Trial registration numberAustralian New Zealand Clinical Trials Registry: ACTRN12621001356853.