PEGALUS: predictivity of elderly age, arterial gas analysis, and lung ultrasound. A new prognostic score for COVID-19 patients in the emergency department-an observational prospective study.

BACKGROUND: Periodic surges of COVID-19 patients seeking care in the hospital environment overwhelm systems reduce the availability of resources for treatment of non-COVID-19 cases (Zheng et al. in J Hosp Infect 106:325-329, 2020). Hospital flow and resource management could be greatly enhanced by differentiating patients who are likely at risk of adverse clinical outcomes from those who could safely be discharged after evaluation and managed outside of the hospital setting (Sun et al. in J Infect Dis 223:38-46, 2021). Herein, we propose a prognostic score named PEGALUS (Predictivity of Elderly age, arterial blood Gas Analysis and Lung UltraSound) that could potentially help clinicians properly and rapidly choose the appropriate allocation of COVID-19 patients admitted to the emergency department (ED). METHODS: This observational prospective study enrolled COVID-19 patients who were admitted to the ED of IRCCS San Raffaele Hospital (HSR). RESULTS: 230 COVID-19 patients were enrolled and 30-day follow-up data was collected. Composite outcome was death or need for oro-tracheal intubation (OTI). 50 patients (21.5%) reached the outcome during the observational period. In multivariate Cox analysis, age, PO2/FiO2 ratio, pCO2, duration of symptoms, and lung ultrasound evaluation were significantly associated with the adverse outcome. We obtained a new scorecard (PEGALUS) according to the hazard ratio of the identified predictors. PEGALUS score performed well in predicting the composite outcome (AUC 0.866, 95% IC 0.812-0.921; p < 0.001). Kaplan-Meier showed that a PEGALUS score < 7 was associated with a good 30-day prognosis (survival rate 97.5%), compared to a PEGALUS score of 7-11 (survival rate 85.9%; p log-rank 0.009) and PEGALUS score > 11 (survival rate 49.3%; p log-rank < 0.001). CONCLUSIONS: PEGALUS score performed at the admission can predict adverse outcomes in patients with COVID-19. The systematic application of this score might permit a more accurate and rapid treatment allocation in this setting.

Gas-exchange deficit and systemic hypoperfusion in COVID-19 and non-COVID-19 young adult patients with pneumonia.

BACKGROUND: Lung damage leading to gas-exchange deficit and sepsis leading to systemic hypoperfusion are well-known features of severe pneumonia. Although frequently described in COVID-19, their prognostic impact in COVID-19-related pneumonia vs COVID-19-urelated pneumonia has never been compared. This study assesses fundamental gas-exchange and hemodynamic parameters and explores their prognostic impact in COVID-19 pneumonia and non-COVID-19 pneumonia. METHODS: We prospectively evaluated arterial pO2/FiO2, alveolar to arterial O2 gradient, shock index, and serum lactate in 126 COVID-19 pneumonia patients, aged 18- 65, presenting to the emergency department with acute, non-hypercapnic respiratory failure. As a control group we identified 1:1 age-, sex-, and pO2/FiO2-matched COVID-19-urelated pneumonia patients. Univariate and multivariable predictors of 30-day survival were identified in both groups. RESULTS: COVID-19 patients showed lower arterial serum lactate concentration (p<0.001) and shock index (p<0.001) values as compared to non-COVID-19 patients. While we did not observe differences in lactate concentration or in shock index values in deceased vs surviving COVID-19 patients (respectively, p=0.7 and p=0.6), non-COVID-19 deceased patients showed significantly higher lactate and shock index than non-COVID-19 survivors (p<0.001 and p=0.03). The pO2/FiO2 was the most powerful determinant of survival by Cox regression multivariate analysis in COVID-19 patients (p=0.006), while it was lactate in non-COVID-19 patients (p=0.001). CONCLUSIONS: As compared to COVID19-unrelated pneumonia, COVID-19 pneumonia outcome seems more strictly correlated to the extent of lung damage, rather than to the systemic circulatory and metabolic derangements typical of sepsis.