Predictors of poor outcome in patients with COVID-19 associated respiratory failure: A retrospective observational study

Abstract

Background: Coronavirus disease 2019 (COVID-19) is majorly known to cause mild to moderate disease, but a small fraction of patients may develop respiratory failure due to diffuse lung injury, requiring management in the intensive care unit (ICU). This study attempts to identify factors that can predict unfavorable outcomes in moderate to severe COVID-19 patients. Methods: Hospital records of 120 COVID-19 patients admitted to the ICU were retrospectively analyzed and data pertaining to demographic, clinical, and laboratory parameters were obtained. These data were then compared with outcome parameters like survival, duration of hospital stay, and various adverse events. Results: Out of 120 patients, 70% were male, with a mean age of 54.44 years [standard deviation (SD) 14.24 years]. Presenting symptoms included breathlessness (100%), cough (94.17%), fever (82.5%), and sore throat (10.83%). Diabetes, hypertension, and chronic obstructive pulmonary disease (COPD) were the common comorbidities associated. Increased serum D-dimer, ferritin, interleukin-6 (IL-6) levels, and unvaccinated status were associated with higher mortality. Overall, 25.83% of patients survived, 24.41% of patients developed septic shock, and 10.6% of patients were discharged on oxygen. World Health Organization (WHO) clinical progression scale score ≤ 6 had 57 and 82% sensitivity and 83 and 77% specificity on days 7 and 14 after admission, respectively, for predicting mortality. A baseline National Early Warning Score 2 (NEWS 2) ≤ 9 had 48% sensitivity and 88% specificity for predicting mortality. Conclusion: Advanced age and associated comorbidities are linked to adverse outcomes in moderate to severe COVID-19. Persistently high D-dimer levels, despite standard treatment, may also contribute to increased mortality. WHO clinical progression scale and NEWS 2 have high specificity for predicting mortality.