Differentiating A- and B-Line Artifacts on a Lung Sonogram: A Feasibility Study Based on Point-of-Care Ultrasonography Users

Abstract

Objective:

It is unknown whether novice point-of-care ultrasonography (POCUS) users can interpret a lung sonogram (LS) for the presence of pulmonary edema. The aim was to evaluate novice POCUS users’ ability to differentiate between A- and B-line artifacts that could indicate pathology on a LS.

Materials and Methods:

A survey featuring 40 LS videos taken from an emergency medicine department’s sample of patients that contained either normal lungs or pulmonary edema and those were distributed to POCUS experts and novice POCUS users. Responses were analyzed for primary outcomes of accuracy, sensitivity, and specificity, compared with the diagnostic gold standard and inter-rater agreement within groups.

Results:

Twenty-five novice POCUS users and 25 expert surveys were included in analysis. Compared with the diagnostic gold standard, novices yielded a sensitivity of 86.8% and a specificity of 81.8%. Experts yielded a sensitivity of 98.4 and a specificity of 99.2. There was a significant difference between experts and novices for median accuracy 90% versus 100% (p < .001). Fleiss’ kappa revealed a near-perfect agreement in the expert group and moderate agreement in the novice POCUS users’ group.

Conclusion:

In this study, the POCUS experts’ interpretation of LS findings was more accurate than that of the novices for the presence or absence of B-lines, although both groups performed well. The high performance of this group of novice POCUS users rivaled previously published results. This would suggest that it may be feasible for novice POCUS users to provide some level of LS interpretation.