The role of point-of-care ultrasound in pediatric acute respiratory distress syndrome: emerging evidence for its use

Abstract

Pediatric acute respiratory distress syndrome (PARDS) remains an important cause of significant morbidity and mortality. The 2015 PALICC definition of PARDS requires chest imaging to diagnose the presence of new pulmonary infiltrate(s). Traditionally chest radiography or computerised tomography have been used. However, these carry the limitations of exposure to ionizing radiation, need to transfer the critically unwell child, lag-time with clinical correlation and lack of immediate results. The use of point of care ultrasound (POCUS) has been well established in adult emergency medicine and critical care. Furthermore, the adult literature clearly demonstrates that lung POCUS is a safe and validated tool, which is highly sensitive and specific when compared to chest radiography for differentiating the causes of respiratory failure, including ARDS. Whilst pediatric specific data is limited, it has been shown that the signs seen in adults are reproducible in critically ill neonates and children. Furthermore, the numerous benefits of POCUS in the paediatric setting are compelling and include lack of ionizing radiation, immediate feedback, promoting time at the bedside of the critically unwell child, and ease of serial assessments. This review article presents the emerging evidence demonstrating that lung POCUS can be used not only to support the diagnosis of pediatric ARDS, but also to assess for complications, monitor progression and thus guide management. We hope it will stimulate much needed collaborative research into this exciting field of imaging and its applications to PARDS and beyond.

Keywords: Point of care testing; respiratory distress syndrome; ultrasound imaging.

Figure 1

Classification on the basis of lung ultrasound and blood gas analysis in dyspnoeic critically ill patients (4).

Figure 2

Imaging diagnostic criteria for acute respiratory distress syndrome (ARDS) in children and adults.

Figure 3

Normal lung point of care ultrasound (POCUS) anatomy on an infant with a linear probe.

Figure 4

Normal M-mode trace of sliding pleura producing the ‘sea-shore’ sign in an infant with a linear probe.

Figure 5

Cases of pediatric acute respiratory distress syndrome (PARDS) as seen with point of care ultrasound (POCUS). (A) Example lung POCUS findings in PARDS (infant with linear probe); (B) example lung POCUS findings in PARDS (teenager with curvi-linear probe); (C) example lung POCUS findings in PARDS (teenager with curvi-linear probe).

Figure 6

Abnormal M-mode trace of no pleural sliding; producing the ‘barcode’ (also called ‘stratosphere’ sign) in an infant with a linear probe.

Figure 7

Summary of features found on lung point of care ultrasound.

Figure 8

Ultrasound reaeration score (23).