Evaluation of the Diagnostic Role of Bedside Lung Ultrasonography in Patients with Suspected Pulmonary Embolism in the Emergency Department

Background: Despite the existence of detailed consensus guidelines, challenges remain regarding efficient, appropriate, and safe imaging methods for the diagnosis of suspected pulmonary embolism.

Aims: To investigate the role of the wedge sign, B-lines, and pleural effusion seen on bedside lung ultrasound in the diagnosis of pulmonary embolism.

Study Design: Diagnostic accuracy study.

Methods: During the first evaluation of patients with suspected pulmonary embolism, bedside lung ultrasound was performed, and the B-lines, wedge sign, and pleural effusion were investigated. Computed tomography angiography was used as a confirmatory test and was compared with the lung ultrasound findings.

Results: Pulmonary embolism was detected in 38 (38%) patients. In the comparison of bedside lung ultrasound results, statistically significant differences were found between the groups in terms of the B-lines and wedge sign (p=0.005 and p>0.001, respectively). There were no significant differences in terms of effusion (p=0.234). Comparison of these findings with computed tomography angiography of the chest showed weak negative correlations between the groups in terms of B-lines (r=-0297) and a moderately positive correlation in terms of the wedge sign (r=0.523). The sensitivity, specificity, and positive and negative predictive values of lung ultrasound findings alone were low. In the logistic regression analysis, the wedge sign (p>0.01, OR=69.45, 95% CI=6.94-695.17) and B-line (p=0.033, OR=1.96, 95% CI=0.41-8.40) were found to be effective in the diagnosis of pulmonary embolism.

Conclusion: Although the role of lung ultrasound has been increasing in the management of critically ill patients, its value is limited and cannot replace the gold standard tests in the diagnosis of pulmonary embolism.