ABSTRACT
Introduction: Coronavirus disease 2019 (COVID-19) patients can develop severe bilateral pneumonia leading to acute respiratory failure. Lung ultrasound (LU) might be a useful tool for the evaluation of these patients. LU Score (LUS) is a twelve-zone examination method for the assessment of lung parenchyma. Aim: To evaluate LUS as a tool for severity assessment and outcome prediction of COVID-19 patients. Methods: Observational and prospective pilot study, including patients admitted to the Intermediate Respiratory Care Unit (IMCU) of Bellvitge University Hospital (Barcelona, Spain). LUS scored from 0-36 points using a convex transducer. Patient data was collected at inclusion. A composite outcome of death or Intensive Care Unit (ICU) admission was used. Patients were followed-up until composite outcome was observed or hospital discharge. Patients were stratified in two groups using LUS>24 as the cut-off point. Results: Thirty-six patients were included. Of them, 69.4% were male. Mean age was 60.2±12.8 years. Median LUS was 23.5 points. A cut-off point for LUS>24 showed 100% sensitivity, 69.2% specificity and AUROC 0.846 for identifying patients with worse prognosis. The composite outcome was observed in 10 (55.6%) patients of the LUS>24 group but not in the LUS<24 group (p<.001). Survival at 7 days from LU was 50% (95%CI 31.5-79.4%) among patients with LUS>24 points. Significant correlations were observed between LUS and Sp02/Fi02 ratio, serum D-Dimer, C-Reactive protein, lactate dehydrogenase and lymphocyte count. Conclusion: LU is a useful tool for the assessment of COVID-19 severity in patients admitted to an IMCU. A LUS>24 points is related to worse prognosis defined as ICU admission requirement or death.