Elsevier

Archives de Pédiatrie

Volume 26, Issue 8, November 2019, Pages 459-465
Archives de Pédiatrie

Research paper
Thoracic ultrasound accuracy for the investigation of initial neonatal respiratory distress

https://doi.org/10.1016/j.arcped.2019.09.009Get rights and content

Abstract

Thoracic ultrasound (TUS) is increasingly studied in neonatal respiratory distress but chest x-ray (CXR) remains the first-line exam. We aimed to evaluate its diagnostic performance for the investigation of unselected causes of neonatal respiratory distress in daily practice. We conducted a descriptive, prospective, and single-center diagnostic accuracy study in a tertiary hospital, including term and preterm newborns who needed a CXR because of respiratory conditions occurring at birth or during the first 24 h of life. TUS was compared to the reference diagnosis, which was the association between the CXR results, the clinical initial context, and the patient's outcome. Fifty-two newborns were included and 104 hemi-thorax ultrasounds were analyzed. Sensitivity, specificity, positive and negative predictive values (PPV, NPV), diagnosis accuracy, as well as the positive and negative likelihood ratio of TUSs were 100% for respiratory distress syndrome (RDS), transient tachypnea of newborn (TTN), pneumomediastinum, meconium aspiration syndrome, and absence of pulmonary disease. TUS also showed 100% sensitivity and NPV for pneumothorax, but specificity was 97% and PPV was 50%. Kappa concordance between TUS and either CXR alone or the radiological/clinical gold standard was 0.79 and 0.95, respectively.

Conclusion

TUS at the newborn's bedside is efficient for investigating the main neonatal respiratory diseases, especially for the confirmation of RDS or TTN and for the exclusion of differential diagnosis or complications.

Introduction

Acute respiratory distress is the main cause of disease in the newborn, especially in premature infants. Its management is first based on clinical symptoms, but has to be completed by lung imaging.

Currently, chest x-ray (CXR) is the primary exam in daily practice in pediatric and adult intensive care units, although it has limited diagnostic performance at the patient's bedside. Thoracic ultrasound (TUS) is increasingly used for acute respiratory distress in adults, based on standardized signs [1]. It has shown better diagnostic performance than CXR, sometimes close to those of CT [2], [3]. In pediatric emergency departments, TUS is also suggested to help the diagnosis of respiratory conditions such as bronchiolitis or pneumonia in children [4], [5]. In neonatal units, in spite of a growing literature, TUS is not commonly used to investigate neonatal respiratory symptoms and CXR remains the first-choice exam. The repetition of CXR could increase the risk of malignant diseases in children, and has to be as limited as possible, whereas TUS is easy to perform and can be repeated without any risk of irradiation. Several studies have already confirmed that ultrasound allows diagnosis for specific neonatal conditions [5], [6], [7], [8], [9]. Usefulness and the possible impact of TUS in daily practice in neonatal intensive care must be evaluated.

Our purpose was to perform a pilot study in our neonatal intensive care unit to analyze the diagnostic TUS performance compared to CXR and clinical course, applied to our global population of unselected newborns so as to evaluate the value of TUS and develop it in our daily practice. We hypothesized that TUS diagnostic performance would be equal or higher than CXR performance in determining the causes of respiratory distress, and that TUS could replace CXR in some situations.

Section snippets

Design and settings

We conducted a descriptive, prospective, and single-center diagnostic accuracy study, following STARD (Standards for the Reporting of Diagnostic Accuracy Studies) guidelines. This study took place between 1st January and 31 May 2014, in a tertiary neonatal hospital.

Inclusion criteria

We consecutively included term and preterm newborns who needed a CXR because of respiratory conditions occurring at birth or during the first 24 h of life, and for whom we could perform a TUS less than 3 h before or after the CXR. Only

Patient and exam characteristics

Among the 288 CXRs performed during the study period, 124 were performed on eligible newborns with initial respiratory symptoms. Sixty-six newborns were not included because no trained neonatologist was available to perform the TUS. We were able to perform TUS within 3 h for 58 newborns (46.8%). Six were excluded because of low TUS quality (n = 2) or prenatal suspicion of a malformation (n = 4). Finally, 52 newborns were included and each of the 104 lungs was independently analyzed.

Table 1 shows the

Discussion

This study found excellent diagnostic performance of TUS for the most frequent causes of immediate neonatal respiratory symptoms: RDS, TTN, pneumothorax, pneumomediastinum, and MAS.

Contrary to the present study, most neonatal studies focused on specific conditions in selected newborns. Only one recent study determined ultrasonography performance to identify the etiology of respiratory distress in 63 neonates, using a radiological and clinical gold standard similar to ours, without selecting

Conclusion

TUS has excellent performance for the diagnosis of the main neonatal respiratory diseases and its results are concordant with CXR and clinical progression. This suggests that TUS might replace CXR as the first-choice method, to identify suspected RDS or TTN in newborns and to eliminate differential diagnoses such as pneumothorax and pneumomediastinum. Further studies will be necessary to prove the safety of this practice and determine the impact of TUS in reducing irradiation and improving

Manuscript edition

The American Manuscript Editors edited this manuscript (certificate verification key: 781-132-506-436-208).

Disclosure of interest

The authors declare that they have no competing interest.

References (30)

  • M. Guerra et al.

    Ultrasound detection of pneumonia in febrile children with respiratory distress: a prospective study

    Eur J Pediatr

    (2016)
  • M. Vergine et al.

    Lung ultrasound accuracy in respiratory distress syndrome and transient Tachypnea of the newborn

    Neonatology

    (2014)
  • S.-W. Chen et al.

    Routine application of lung ultrasonography in the neonatal intensive care unit

    Medicine (Baltimore)

    (2017)
  • P. Tomà et al.

    Chest ultrasound in children: critical appraisal

    Pediatr Radiol

    (2013)
  • J. Liu et al.

    Diagnosis of neonatal transient tachypnea and its differentiation from respiratory distress syndrome using lung ultrasound

    Medicine (Baltimore)

    (2014)
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