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Objective: To determine the accuracy of pre-extubation lung ultrasound (LUS) to predict reintubation in preterm infants born <32 weeks' gestation., Design: Prospective diagnostic accuracy study., Setting: Two neonatal intensive care units., Methods: Anterior 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)., Results: One 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., Conclusions: In 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 Number: Australian New Zealand Clinical Trials Registry: ACTRN12621001356853., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Effective lung protective ventilation requires reliable, real-time estimation of lung volume at the bedside. Neonatal clinicians lack a readily available imaging tool for this purpose., Objective: To determine the ability of lung ultrasound (LUS) of the dependent region to detect real-time changes in lung volume, identify opening and closing pressures of the lung, and detect pulmonary hysteresis., Methods: LUS was performed on preterm lambs (n=20) during in vivo mapping of the pressure-volume relationship of the respiratory system using the super-syringe method. Electrical impedance tomography was used to derive regional lung volumes. Images were blindly graded using an expanded scoring system. The scores were compared with total and regional lung volumes, and differences in LUS scores between pressure increments were calculated., Results: Changes in LUS scores correlated moderately with changes in total lung volume (r=0.56, 95% CI 0.47-0.64, p<0.0001) and fairly with right whole (r=0.41, CI 0.30-0.51, p<0.0001), ventral (r=0.39, CI 0.28-0.49, p<0.0001), central (r=0.41, CI 0.31-0.52, p<0.0001) and dorsal (r=0.38, CI 0.27-0.49, p<0.0001) regional lung volumes. The pressure-volume relationship of the lung exhibited hysteresis in all lambs. LUS was able to detect hysteresis in 17 (85%) lambs. The greatest changes in LUS scores occurred at the opening and closing pressures., Conclusion: LUS was able to detect large changes in total and regional lung volume in real time and correctly identified opening and closing pressures but lacked the precision to detect small changes in lung volume. Further work is needed to improve precision prior to translation to clinical practice., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: Lung ultrasound (LUS) has shown promise as a diagnostic tool for the evaluation of the newborn with respiratory distress. No study has described LUS during 'normal' transition. Our goal was to characterise the appearance of serial LUS in healthy newborns from the first minutes after birth until airway liquid clearance is achieved., Study Design: Prospective observational study., Setting: Single-centre tertiary perinatal centre in Australia., Patients: Of 115 infants born at ≥35 weeks gestational age, mean (SD) gestational age of 38 6/7 weeks±11 days, mean birth weight of 3380±555 g, 51 were delivered vaginally, 14 via caesarean section (CS) after labour and 50 infants via elective CS., Interventions: We obtained serial LUS videos via the right and left axillae at 1-10 min, 11-20 min and 1, 2, 4 and 24 hours after birth., Main Outcome Measures: LUS videos were graded for aeration and liquid clearance according to a previously validated system., Results: We analysed 1168 LUS video recordings. As assessed by LUS, lung aeration and airway liquid clearance occurred quickly. All infants had an established pleural line at the first examination (median=2 (1-4) min). Only 14% of infants had substantial liquid retention at 10 min after birth. 49%, 78% and 100% of infants had completed airway liquid clearance at 2, 4 and 24 hours, respectively., Conclusions: In healthy transitioning newborn infants, lung aeration and partial liquid clearance are achieved on the first minutes after birth with complete liquid clearance typically achieved within the first 4 hours of birth., Trial Registration Number: ANZCT 12615000380594., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Background: Cranial ultrasound cerebral biometric measurements have been used in preterm neonates, particularly in cases of ventriculomegaly. While cerebral biometric measures using MRI have been found to correlate with long-term outcome, the relationship between cranial ultrasound biometric measures and neurodevelopmental outcome has not been established., Objective: To assess the relationship between ventricular size at 1 month of age using cranial ultrasound and neurodevelopmental outcome at 2 years in very preterm infants., Method: Digital cranial ultrasound images taken between 25 and 35 days of age of 44 infants born at less than 30 weeks' gestation were analysed independently by two observers. Infants with significant ultrasound abnormalities were excluded. A range of ultrasound linear measures were correlated with Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) motor, language and cognitive composite scores at 2 years using linear regression., Results: Larger lateral ventricular sizes (anterior horn width, ventricular height, midbody ventricular height) and larger ventricular-brain biparietal ratios were related to poorer motor composite score at 2 years. A ventricular-brain ratio of less than 0.3 was reassuring with regard to motor outcome. Poorer language composite scores at 2 years were associated with larger midbody ventricular heights. There was little evidence of a relationship with the cognitive composite score., Conclusions: Larger lateral ventricles in the parietal region at a month of age were related to poorer motor development at 2 years. Larger ventricular measurements were also related to slower early language development. The role of cranial ultrasound biometric measures as biomarkers of later outcome in very preterm infants warrants further investigation.