Lung Consolidation Locations for Optimal Lung Ultrasound Scanning in Diagnosing Pediatric Pneumonia

Objectives: Lung ultrasound (US) has been shown to be accurate in diagnosing pneumonia in children. Evidence to inform an optimal scanning protocol is limited. Our objective is to describe an optimized lung US scanning protocol for pediatric pneumonia based on the anatomic location and transducer orientation.

Methods: We performed a secondary analysis of data and images from 2 prospective lung US studies for the emergency department diagnosis of pneumonia in children (0-21 years). The anatomic location of each lung consolidation was mapped to 1 or more of 6 anatomic zones on the chest, noting the transducer orientation (sagittal or transverse) in which it was identified.

Results: Seventy-eight patients were included; 51% were female, and the median age was 3 years (interquartile range, 1-7 years). Overall, 46.5% (95% CI confidence interval [CI], 37.9%-55.1%) of lung zones with a visible consolidation were posterior; 31.0% (95% CI, 23.0%-39.0%) were anterior; and 22.5% (95% CI, 15.3%-29.1%) were axillary. A total of 54.3% (95% CI, 45.7%-62.9%) of affected lung zones were in the lower lung compared to the upper lung (8.5%; 95% CI, 3.7%-13.3%) and middle lung (37.2%; 95% CI, 28.9%-45.5%). Most lung consolidations were seen in both transducer orientations: 96.2% (95% CI, 92.0%-100%) of patients had a visible consolidation on the transverse view, whereas 85.9% (95% CI, 78.2%-93.6% had a consolidation on the sagittal view.

Conclusions: Efficient lung US scanning may start with the posterior, anterior, and then lateral chest zones if no pneumonia is identified. A transverse transducer orientation detects more pneumonia than a sagittal orientation. Omission of either orientation or any lung zone may miss pneumonia.