Neonatal respiratory distress syndrome: Chest X-ray or lung ultrasound? A systematic review

Abstract

Background and aim: Neonatal respiratory distress syndrome is a leading cause of morbidity in preterm newborn babies (<37 weeks gestation age). The current diagnostic reference standard includes clinical testing and chest radiography with associated exposure to ionising radiation. The aim of this review was to compare the diagnostic accuracy of lung ultrasound against the reference standard in symptomatic neonates of 42 weeks gestation age. Methods: A systematic search of literature published between 1990 and 2016 identified 803 potentially relevant studies. Six studies met the review inclusion criteria and were retrieved for analysis. Quality assessment was performed before data extraction and meta-analysis. Results: Four prospective cohort studies and two case control studies included 480 neonates. All studies were of moderate methodological quality although heterogeneity was evident across the studies. The pooled sensitivity and specificity of lung ultrasound were 97% (95% confidence interval [CI] 94-99%) and 91% (CI: 86-95%) respectively. False positive diagnoses were made in 16 cases due to pneumonia (n ¼ 8), transient tachypnoea (n ¼ 3), pneumothorax (n ¼ 1) and meconium aspiration syndrome (n ¼ 1); the diagnoses of the remaining three false positive results were not specified. False negatives diagnoses occurred in nine cases, only two were specified as air-leak syndromes. Conclusions: Lung ultrasound was highly sensitive for the detection of neonatal respiratory distress syndrome although there is potential to miss co-morbid air-leak syndromes. Further research into lung ultrasound diagnostic accuracy for neonatal air-leak syndrome and economic modelling for service integration is required before lung ultrasound can replace chest radiography as the imaging component of the reference standard.

Diagnostic value of lung ultrasound for neonatal respiratory distress syndrome: a meta-analysis and systematic review

“…Copetti et al [11] claimed that, in comparison with the transabdominal approach, the transthoracic technique could examine all the lung fields rather than only the base. This finding is in accordance with the findings of Hiles et al [34], suggesting that the transthoracic technique may be the better diagnostic approach for avoiding false-positive diagnoses and has the clinical advantage of reducing unnecessary additional testing and interventions. Second, the subgroup analysis also indicated that studies with a detection interval between CXR and LUS of less than 6 hours had a nonsignificantly higher specificity than those with a detection interval less than 24 hours.…”

“…The clinical features of NRDS are characterized by tachypnoea, nasal flaring, expiratory grunting, chest retractions and cyanosis [1], and the risk for this syndrome increases with decreasing gestational age (GA). The incidence of NRDS was found to be 93% in extremely preterm infants (GA 28 weeks or below) [2] and 10.5%, 6%, 2.8%, 1% and 0.3% in infants born at 34,35,36,37, and ≥38 weeks gestation, respectively [3].…”

A Multicenter Lung Ultrasound Study on Transient Tachypnea of the Neonate

“…An irregular pleural-line image with significant “subpleural” consolidations is a typical sign of RDS, pneumonia, and meconium aspiration syndrome [20-23]. Consistent with previous studies, our TTN neonates showed a regular ultrasound appearance of the pleura.…”

Does lung ultrasound score predict the need for surfactant in extremely preterm neonates?

“…While the authors used low FiO2 cut‐offs (30% for ≤ 28 weeks and 40% for > 28 weeks) to administer surfactant, the FiO2 requirement constituting CPAP failure varies in the literature from 30‐75% –restricting the applicability of these results to institutions which utilise similar thresholds. Additionally, although other studies report good reliability of the LUS , a recent systemic review by Hiles, et al., found only moderate quality evidence to support its use . Thus, more research is needed prior to universal implementation, so for now this study's results are limited to NICUs with similar expertise.…”