Use of lung ultrasound and and aEEG patterns to predict the need for mechanical ventilation and the readiness for extubation in neonates with respiratory distress

Abstract

Objective. The aim of the study was to establish if lung ultrasound findings could anticipate the need for intubation and mechanical ventilation in neonates with respiratory distress and if lung ultrasound and aEEG criteria could be used in appreciation of the readiness for extubation of the neonatal patients resulting in a decrease of the rate of extubation failure. Material and method. There were analyzed the cases of 50 late preterm and early term neonates presenting with respiratory distress. Lung ultrasound was performed during the first 4 hours after delivery in all the neonates and then as clinically indicated in the case of ventilated patients. A lung ultrasound was performed in all the ventilated patients before extubation. 12 of the 25 ventilated patients were also monitored by aEEG. The decisions regarding the intubation and mechanical ventilation and the moment of extubation of the patients were taken by the clinicians in accordance with the local and international guidelines. The extubation failure was defined as the need to re-intubate the patient in the first 24 hours after the extubation. The lung ultrasound pattern was considered as normal if the image was consisting of A lines with rare B lines or ”double lung point” as in the case of the delayed absorption of fetal lung fluid and abnormal in the case of “white lung” appearance (coalescent B lines) or an image of consolidation. A normal aEEG was defined as the presence of a continuous normal voltage pattern with sleep-wake cycles present and an abnormal aEEG as either discontinuous normal voltage, burst-suppression, low voltage or flat background patterns. The lung ultrasound patterns in the first hours of life were compared between patients that needed intubation and those that did not need mechanical ventilation. The lung ultrasound and aEEG patterns before extubation were compared between the patients that did not need re-intubation and those with extubation failure. Results. An abnormal image on lung ultrasound was significantly associated with the risk of intubation (p < 0.001) (sensitivity 84%, specificity 100%, positive predictive value 100% and negative predictive value 86.2%) An abnormal lung ultrasound pattern before extubation was associated with a significant risk of extubation failure (p < 0.049) (sensitivity 75%, specificity 85%, positive predictive value 50%, negative predictive value 94.7%). In the case of the subset of patients in which aEEG was performed, an abnormal aEEG pattern was significantly associated with extubation failure (p < 0.034) (sensitivity 100%, specificity 88%, positive predictive value 75%, negative predictive value 100%). In the case of association of the two parameters (lung ultrasound and aEEG pattern) there was again a statistically significant association between the abnormal patterns and extubation failure. Conclusions. An abnormal lung ultrasound during the first hours of life is a strong predictor for the need of intubation and mechanical ventilation in the neonates with respiratory distress. The normal lung ultrasound pattern just before extubation is predictive of a good evolution without the need for re-intubation of the patient. A normal aEEG pattern at the same time is associated also with a decreased risk of extubation failure.

Accuracy of lung ultrasound in predicting extubation failure in neonates: A systematic review and meta‐analysis

“…20,21 Moreover, recent studies have indicated that LU is a promising tool for prediction of extubation outcomes (success or failure) in neonates. [22][23][24][25][26][27][28][29] These recent findings in neonates are consistent with recent systematic review in adults which concluded that LU can assist in determining the ideal time for extubation. 30 To the best of our knowledge, there has been no systematic evaluation of the diagnostic accuracy of neonatal LU score (LUS) in predicting extubation failure.…”

“…Out of the eight included studies, radiologists conducted LU scans in three studies, 22,23,28 while pediatricians/neonatologists performed the scans in the remaining studies. Quantitative assessment of LU scans, in which a score was given, was conducted in seven studies, whereas one study performed a qualitative assessment 25 . The quantitative scores varied across studies, with a total of 18 points in two studies, 23,24 24 points in one study, 29 36 points in three studies, 22,26,27 and 70 points in one study 28 .…”

“…Additionally, the cut‐off points for selected sensitivity and specificity were variable. Four studies limited the scan to anterior and lateral lung zones, 23–25,29 and the time window for defining extubation failure ranged from 1 to 7 days.…”

“…Prespecified subgroup analysis was performed for studies using LUS of anterior and lateral six zones (four studies, N = 198), 23–25,29 which showed pooled sensitivity of 0.83 (95% CI: 0.67−0.92), specificity of 0.82 (95% CI: 0.77−0.88), pooled diagnostic odds ratio of 19.32 (95% CI: 7.83−47.68), and AUC 0.91 (95% CI: 0.76−1.0). We observed low statistical heterogeneity (Higgins' I 2 0%, Cochran's Q p value .52).…”

“…Other modified scoring systems were later published 39 . Four studies limited their scans to the anterior and lateral lung zones in each lung 23–25,29 . Louis et al found that LUS was higher in the dependent lung zones when scans were performed immediately after changing infants' position 40 .…”