Time to hospitalisation, CT pulmonary involvement and in-hospital death in COVID-19 patients in an Emergency Medicine Unit

Background: Patients with coronavirus disease 2019 (COVID- 19) are often treated at home given the limited healthcare resources. Many patients may have sudden clinical worsening and may be already compromised at hospitalisation. We investigated the burden of lung involvement according to the time to hospitalisation. Methods: In this observational cohort study, 55 consecutive COVID- 19- related pneu- monia patients were admitted to the Emergency Medicine Unit. Groups of lung in- volvement at computed tomography were classified as follows: 0 (<5%), 1 (5%- 25%), 2 (26%- 50%), 3 (51%- 75%) and 4 (>75%). We also investigated in- hospital death and the predictive value of Yan- XGBoost model and PREDI- CO scores for death. Results: The median age was 74 years and 34 were men. Time to admission increased from 2 days in group 0 to 8.5- 9 days in groups 3 and 4. A progressive increase in LDH, CRP and d- dimer was found across groups, while a decrease of lymphocytes paO2/FiO2 ratio and SpO2 was found. Ten (18.2%) patients died during the in- hospital staying. Patients who died were older, with a trend to lower lymphocytes, a higher d- dimer, creatine phosphokinase and troponin T. The Yan- XGBoost model did not ac- curately predict in- hospital death with an AUC of 0.57 (95% confidence interval [CI] 0.37- 0.76), which improved after the addition of the lung involvement groups (AUC 0.68, 95%CI 0.45- 0.90). Conversely, a good predictive value was found for the origi- nal PREDI- CO score with an AUC of 0.76 (95% CI 0.58- 0.93) which remained similar after the addition of the lung involvement (AUC 0.76, 95% CI 0.57- 0.94). Conclusion: We found that delayed hospital admission is associated with higher lung involvement. Hence, our data suggest that patients at risk for more severe disease, such as those with high LDH, CRP and d- dimer, should be promptly referred to hos- pital care.