Lung Assessment with Point-of-Care Ultrasound in Respiratory Coronavirus Disease (COVID-19): A Prospective Cohort Study

Abstract

Lung ultrasound (LUS) has shown promising diagnostic potential in different pulmonary conditions. We evaluated the diagnostic accuracy of LUS for pulmonary COVID-19. In this prospective cohort study at a Swiss tertiary care center, patients hospitalized with suspected COVID-19 were scanned using a 12-zone protocol. Association of a summation score (0-36 points) with the final diagnosis was tested using the area under the receiver operating characteristic curve and sensitivity and specificity at different cutoff points. Of the 49 participants, 11 (22%) were later diagnosed with COVID-19. LUS score showed excellent diagnostic performance, with an odds ratio of 1.30 per point (95% confidence interval [CI], 1.09-1.54, p = 0.003) and an area under the curve of 0.85 (95% CI, 0.71-0.99). At a cutoff of 8/36 points, 10 of 11 participants later diagnosed with COVID-19 were correctly predicted (sensitivity 91%, 95% CI, 59%-100%), and 29 of the 38 who were not diagnosed with COVID-19 were correctly ruled out (specificity 76%, 95% CI, 60%-89%). LUS demonstrated promising discriminatory potential in people hospitalized with suspected COVID-19.

Keywords: COVID-19; Coronavirus disease; Interstitial syndrome; Lung ultrasound; Pleura ultrasound; Pneumonia; Point of care ultrasound; SARS-CoV-2.

Fig. 1

Lung and pleural alterations were documented by semi-quantitative assessment of B-lines and consolidations, adapted from Manivel et al. (2020). A-lines are horizontal linear artifacts mirroring the pleural line; B-lines are vertical comet-tail-like artifacts indicating increased interstitial density that move with the pleural line during respiration; subpleural consolidations have a relatively hypoechoic heterogeneous echotexture with blurred and irregular margins. LUSS = lung ultrasound score.

Fig. 2

Flowchart of participants included for LUS examination, with primary (confirmed COVID-19) and secondary outcomes (ICU transfer and/or in-hospital death). COPD = chronic obstructive pulmonary disease; ICU = intensive care unit; LUS = lung ultrasound; LUSS = lung ultrasound score.

Fig. 3

Ultrasound presentation of B-lines, consolidations and lung ultrasound scores at different locations in patients with and without COVID-19. Boxplots around median and inter-quartile ranges, with adjacent lines for the most extreme values within 1.5 IQR of the nearer quartile. IQR = inter-quartile range; LUSS = lung ultrasound score.