Oxygen markers for predicting COVID-19 - related pneumonia mortality

Abstract

Introduction: the value of oxygen as a prognostic maker of mortality due to COVID-19 pneumonia has not been evaluated at the Hospital General Docente "Dr. Agostinho Neto". Objective: to identify the values of oxygenation markers for prognosing mortality caused by COVID-19 pneumonia at the Hospital General Docente "Dr. Agostinho Neto" de Guantánamo, Cuba, throughout period 2020-2021. Method: a cohort of 276 patients with COVID-19 pneumonia was studied. Peripheral oxygen saturation (SpO2), arterial oxygen saturation (SaO2), the difference between the oxygen concentration in the alveoli and arterial system (DA-aO2), arterial oxygen pressure ratio (PaO2) and inspired oxygen fraction (FiO2) [PaO2/FiO2] were studied. The association between variables and deceased discharge was determined using the Chi-square technique and the Odds Ratio (OR) calculation. Results: the variable with the highest positive predictive value was SpO2 (87.3 %) with a value lower than 90 mmHg at admission. The highest negative predictive value was recorded for the DA-aO2 variable (95.6%), less than 20 mmHg at 48 hours after admission. Attributable risk was higher for PaO2/FiO2 ratio, less than 300 mmHg (0.59), at admission (0.52). Attributable risk percent was higher for the variable DA-aO2 20 mmHg at admission (95.8 %) and at 48 hours after admission (95.3 %). Conclusions: abnormal DA-aO2, PaO2/FiO2 ratio, SaO2 and SpO2, at admission and 48 hours after admission, are predictive markers of mortality in patients with COVID-19.

Keywords

• covid-19
• marcadores de oxigenación
• neumonía causada por la covid-19
• mortalidad
• factores predictivos