Lung ultrasound in children with pneumonia: interoperator agreement on specific thoracic regions

The objective of this study was to evaluate the interoperator agreement of lung ultrasonography (LUS) on specific thoracic regions in children diagnosed with pneumonia and to compare the findings of the LUS with the chest X-ray. Participants admitted to the ward or PICU underwent LUS examinations performed by an expert and a novice operator. A total of 261 thoracic regions in 23 patients were evaluated. Median age and weight of participants were 30 months and 11.6 kg, respectively. A substantial overall agreement between operators was found for normal lung tissue (κ = 0.615, 95% confidence interval (95% CI) = 0.516-0.715) and for consolidations (κ = 0.635, 95% CI = 0.532-0.738). For B-lines, a moderate agreement was observed (κ = 0.573, 95% CI = 0.475-0.671). An almost perfect agreement was found for pleural effusion (κ = 0.868, 95% CI = 0.754-0.982). The diagnosis of consolidations by LUS showed a high sensitivity (93% for both operators) but a low specificity (14% for expert and 25% for novice operator). While intubated patients presented significantly more consolidations, nonintubated patients presented more normal ultrasound patterns.Conclusion: Even when performed by operators with very distinct degrees of experience, LUS had a good interoperator reliability for detecting sonographic patterns on specific thoracic regions. What is Known: • Lung ultrasound is feasible, safe, and highly accurate for the diagnosis of pneumonia in children; however, it does not allow global visualization of the thorax in a single moment as in chest X-rays, and, similar to the stethoscope, partial thorax assessments must be performed sequentially. What is New: • This is the first study evaluating the agreement of LUS on specific thoracic regions between operators with distinct degrees of experience performing the sonograms. • There is a good agreement between an expert operator and a novice operator who underwent a brief theoretical-practical training program on LUS.