Utility of a Pulmonary Oedema Score for Predicting the Need for Mechanical Ventilation in COVID-19 Patients in a General Hospital

Abstract

BackgroundThe Radiographic Assessment of Lung Edema (RALE) score has been used to estimate the extent of pulmonary damage in patients with acute respiratory distress syndrome and might be useful in patients with COVID-19.Aim of the studyTo examine factors associated with the need for mechanical ventilation in hospitalized patients with a clinical diagnosis of COVID-19, and to estimate the predictive value of the RALE score.MethodsIn a series of patients admitted between April 14 and August 28, 2020, with a clinical diagnosis of COVID-19, we assessed lung involvement on the chest radiograph using the RALE score. We examined factors associated with the need for mechanical ventilation in bivariate and multivariate analysis. The area under the receiver operating curve (AUC) indicated the predictive value of the RALE score for need for mechanical ventilation.ResultsAmong 189 patients, 90 (48%) were judged to need mechanical ventilation, although only 60 were placed on a ventilator. The factors associated with the need for mechanical ventilation were a RALE score >6 points, age >50 years, and presence of chronic kidney disease. The AUC for the RALE score was 60.9% (95% CI 52.9–68.9), indicating it was an acceptable predictor of needing mechanical ventilation.ConclusionsA score for extent of pulmonary oedema on the plain chest radiograph was a useful predictor of the need for mechanical ventilation of hospitalized patients with COVID-19.