Clinical characteristics and mortality in mechanically ventilated COVID-19 patients: prospective cohort study

Abstract

Introduction: Factors associated with mortality among mechanically ventilated COVID-19 patients have been scarcely studied in Latin America. Objective: To identify factors associated with mortality in mechanically ventilated COVID-19 patients. Methods: This prospective study was undertaken in a single center between April and October 2020, recruiting COVID-19 patients managed with mechanical ventilation. We excluded patients who died within the first 24 hours after endotracheal intubation. Clinical characteristics, laboratory results, ventilation interventions, and outcomes were collected and compared between the deceased and surviving groups. The association between these factors and hospital death was examined, and relevant covariates were included in a multivariate logistic regression model. Results: A total of 273 patients were included (72.5% male), the mortality rate was 37% (95% CI 31% - 43%), and the median age was 63 years (IQR 52-72). The most frequent comorbidity was hypertension (45%). Factors associated with mortality were: older age (OR 1.08; 95% CI 1.05-1.11), male gender (OR 2.79; 95% CI 1.30-6.01), immunosuppression (OR 3.98; 95% CI 1.57-10.06), thrombocytopenia (OR 3.84; CI 95% 1.47-10.01), driving pressure (OR 1.20; 95% CI 1.07-1.34) and the use of dialysis (OR 4.94; 95% CI 2.56-9.51). Chronic hypertension (OR 0.35; 95% CI 0.17-0.71) and fever on admission (OR 0.51; 95% CI 0.27-0.98) were found to have a protective effect. Conclusions: Older age, male sex, immunosuppression, thrombocytopenia, increased driving pressure, use of dialysis, absence of fever, or arterial hypertension were associated with an increased risk of mortality among mechanically ventilated COVID-19 patients.