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Abstract Timing is crucial when deciding whether a patient can be successfully weaned from mechanical ventilation or not. As both premature extubation and unnecessary delay have been associated with poor outcome (Soliman et al., 2019). There are no enough guidelines for the assessment of readiness of a newborn for extubation. Lung ultrasound can detect reduction in parenchymal aeration from respiratory, cardiac, or diaphragmatic origin. This reduction is quantified through LUS score, a scale which values range from 0 to 36 points, calculated from the sum of the grades assigned to different aeration patterns observed in every examined area of the lung (Llamas-Álvarez et al., 2017). There is increasing interest in the use of diaphragm ultrasound in adult as a tool to identify and track diaphragm dysfunction specially to follow patients who will be extubated from mechanical ventilation, and if they will remain free of invasive ventilation afterwards (Turton et al., 2019). Our study was designed to assess the value of lung ultrasound score and diaphragm ultrasound parameters as predictor of successful extubation in neonates. We recruited 39 ventilated newborn patients. They were 13 fullterms and 26 preterms. Mean birth weight was 1.94kg.Twenty two patients were males and 17 were females.The most common diagnosis was respiratory distress syndrome 51.3 % of our patients, followed by congenital pneumonia 25.6%. We divided the patients into two groups according to their extubation trial whether succeeded or not (1) Success group; this group included 25 patients (64.1%) (2) Failure group which included 14 patients (35.9%). The differences were not significant between the two groups as regards both weight and gestational age. The mortality rate was higher in patients who failed their weaning trial. Surfactant was required in 50% of the failure group which was significantly higher than success group (12% only). Only three of our patients had BPD, yet they were all in the failure group, which may indicate that BPD is a risk factor for failure. As regards initial ventilatory settings higher PIP, PEEP and MAP were needed for the patients who failed extubation later in comparison to those who had successful weaning. The pre-extubation ventilatory settings; respiratory rate, MAP and FiO2 were higher in the failure group, in comparison to success group. There was a significant difference between two groups as regards ventilation mode chosen for non- invasive ventilation post extubation, where those who required NIPPV rather than CPAP, where more likely to be in the failure group. Also those who were put on CPAP in the failure group required higher PEEP. As for those in the failure group who required post-extubation NIPPV required higher PIP, PEEP and respiratory rates in relation to success group. The failure group had higher LUS score at the time of intubation and pre- extubation and post-extubation in comparison to the successful group. The LUS score pre-extubation was specifically of interest in the aim of assessing its validity to be a predictor of extubation success to be used in clincal practice. Using ROC curve, we concluded that the best cut off value for LUS score pre-extubation to predict successful extubation was ≤10 with sensitivity 76% and specificity 64.3% (AUC 75). We found no atrophy in diaphragm thickness in the studied patients. On the contrary, there was increase in the mean thickness of right and left diaphragm in both inspiration and expiration in all the patients, although not statistically significant. Still higher left diaphragm inspiration and expiration thickness pre-extubation were found in the failure group in comparison to success group. There was a significant positive correlation between LUS score pre-extubation and both left diaphragm thickness at inspiration and expiration. Using ROC curve, the best cut off value for left diaphragm expiration thickness pre-extubation to predict successful extubation trial was ≤0.22 cm with sensitivity 70.8% and specificity 71.4% (AUC 75.6). Also regarding left diaphragm inspiration thickness, the best cut off value on initiation of ventilation to predict successful extubation trial was ≤0.28 cm with sensitivity 88% and specificity 57% (AUC 75.4). We also demonstrated that SBT can be used as a predictor of successful extubation with 63.6 % sensitivity and 84.2 % specificity. |