Chest X-ray for predicting mortality and the need for ventilatory support in COVID-19 patients presenting to the emergency department

OBJECTIVES To evaluate the inter-rater agreement of chest X-ray (CXR) findings in coronavirus disease 2019 (COVID-19) and to determine the value of initial CXR along with demographic, clinical, and laboratory data at emergency department (ED) presentation for predicting mortality and the need for ventilatory support.
METHODS A total of 340 COVID-19 patients who underwent CXR in the ED setting (March 1-13, 2020) were retrospectively included. Two reviewers independently assessed CXR abnormalities, including ground-glass opacities (GGOs) and consolidation. Two scoring systems (Brixia score and percentage of lung involvement) were applied. Inter-rater agreement was assessed by weighted Cohen's kappa (κ) or intraclass correlation coefficient (ICC). Predictors of death and respiratory support were identified by logistic or Poisson regression.
RESULTS GGO admixed with consolidation (n = 235, 69%) was the most common CXR finding. The inter-rater agreement was almost perfect for type of parenchymal opacity (κ = 0.90), Brixia score (ICC = 0.91), and percentage of lung involvement (ICC = 0.95). The Brixia score (OR: 1.19; 95% CI: 1.06, 1.34; p = 0.003), age (OR: 1.16; 95% CI: 1.11, 1.22; p<0.001), PaO 2 /FiO 2 ratio (OR: 0.99; 95% CI: 0.98, 1; p = 0.002), and cardiovascular diseases (OR: 3.21; 95% CI: 1.28, 8.39; p = 0.014) predicted death. Percentage of lung involvement (OR: 1.02; 95% CI: 1.01, 1.03; p = 0.001) and PaO 2 /FiO 2 ratio (OR: 0.99; 95% CI: 0.99, 1.00; p<0.001) were significant predictors of the need for ventilatory support.
CONCLUSIONS CXR is a reproducible tool for assessing COVID-19 and integrates with patient history, PaO 2 /FiO 2 ratio, and SpO 2 values to early predict mortality and the need for ventilatory support.
KEY POINTS • Chest X-ray is a reproducible tool for assessing COVID-19 pneumonia. • The Brixia score and percentage of lung involvement on chest X-ray integrate with patient history, PaO 2 /FIO 2 ratio, and SpO 2 values to early predict mortality and the need for ventilatory support in COVID-19 patients presenting to the emergency department.

as reported in: Eur Radiol. 2020 Oct 8 [Epub ahead of print]