Lung ultrasound as a screening tool for SARS‐CoV‐2 infection in surgical patients

Abstract

Purpose To evaluate the diagnostic performance of lung ultrasound (LUS) in screening for SARS‐CoV‐2 infection in patients requiring surgery. Methods Patients underwent a LUS protocol that included a scoring system for screening COVID‐19 pneumonia as well as RT‐PCR test for SARS‐CoV‐2. The receiver operator characteristic (ROC) curve was determined for the relationship between LUS score and PCR test results for COVID‐19. The optimal threshold for the best discrimination between non‐COVID‐19 patients and COVID‐19 patients was calculated. Results Among 203 patients enrolled (mean age 48 years; 82 males), 8.3% were COVID‐19‐positive; 4.9% were diagnosed via the initial RT‐PCR test. Of the patients diagnosed with SARS‐CoV‐2, 64.7% required in‐hospital management and 17.6% died. The most common ultrasound findings were B lines (19.7%) and a thickened pleura (19.2%). The AUC of the ROC curve of the relationship of LUS score with a cutoff value >8 versus RT‐PCR test for the assessment of SARS‐CoV‐2 pneumonia was 0.75 (95% CI 0.61–0.89; sensitivity 52.9%; specificity 91%; LR (+) 6.15, LR (−) 0.51). Conclusion The LUS score in surgical patients is not a useful tool for screening patients with potential COVID‐19 infection. LUS score shows a high specificity with a cut‐off value of 8.