Accuracy of Bedside Lung Ultrasound as a Rapid Triage Tool for Suspected Covid-19 Cases

The novel coronavirus disease 2019 (Covid-19) outbreak began in China. The characteristic of the disease is development of pneumonia. We aimed to investigate the accuracy of bedside lung ultrasound (BLUS) for diagnosing Covid-19 pneumonia, and its effectiveness for the correct triage of patients with suspected Covid-19 in the emergency department (ED).

This study was a prospective, cross-sectional cohort study. During their shifts, 3 accredited and certificated emergency physicians performed BLUS using BLUE protocol at the triage area of the ED on patients with suspected Covid-19. All of the patients underwent chest computed tomography. The BLUS findings were statistically compared with formal radiology reports of computed tomographies as the criterion standard for the diagnosis of Covid-19 pneumonia. Kolmogorov-Smirnov analysis, Shapiro-Wilk test, and Q-Q plots were performed with 95% confidence intervals (CIs) for statistical analysis.

A total of 72 patients were included in the study. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of BLUS were 96.9% (95% CI, 84.2%-99.9%), 92.3% (95% CI, 79.1%-98.3%), 84.3% (95% CI, 64.5%-94.1%), 98.6% (95% CI, 91.1%-99.8%), and 93.7% (95% CI, 85.3%-98.0%), respectively. The positive and negative predictive values were 84.3% (95% CI, 64.5%-94.1%) and 98.6% (95% CI, 91.1%-99.8%), respectively. The area under curve was found to be 0.946 (95% CI, 0.866-0.986; P < 0.0001).

Bedside lung ultrasound can be used to detect the presence of pulmonary involvement in suspected cases of Covid-19 for the effective triage of patients in the ED.