CovHos score for predicting severe respiratory failure in COVID-19 patients presenting at the emergency department.

Hospitalization of COVID-19 patients in low-intensity wards may put patients at risk in case of clinical deterioration. We tested CovHos score in predicting severe respiratory failure (SFR) at emergency department (ED) admission. This is a monocentric observational prospective study enrolling adult COVID-19 patients admitted to the ED of IRCCS AOU di Bologna Policlinico S.Orsola in October 2020, both discharged and hospitalized. Patients were then dichotomized based on days from symptoms onset. Main outcome was the occurrence of SRF. Receiver operating characteristic (ROC) analysis was used to identify cut-off and corresponding accuracy. A CovHos cut-off of 22 yielded a sensitivity of 84.7% and specificity of 75.3% in predicting SRF (AUROC 0.856; CI 95% 0.813-0.898). In patients with symptoms onset up to 8 days, a CovHos cut-off of 22 was able to predict SRF with a sensitivity of 91.7% and a specificity of 78.6% (AUROC 0.901; CI 95% 0.861-0.941). Negative predictive value (NPV) was 97.1%. A CovHos score lower than 22, in patients with COVID-19 symptoms onset dated 8 or less days prior to the ED admittance, had a NPV of 97.1% for the development of SRF, meaning that almost none of those patients will evolve into SRF and could be therefore suitable for a lower intensity of care.