Mortality Predictors of Pre-variant SARS-CoV-2 Infected ARDS Patients Receiving Favipiravir and Tocilizumab

Objective: In this study, we investigated the risk factors affecting mortality of critically ill COVID-19-related acute respiratory distress syndrome (ARDS) patients who were followed up in the intensive care unit (ICU) and received tocilizumab and favipiravir treatments together before vaccination. Materials and Methods: The data of patients who were followed up and treated between 1, July 2020 and 5, October 2020 were retrospectively analyzed. Demographic data of the patients (age, gender), acute physiology and chronic health evaluation score II (APACHE II), sequential organ failure assessment (SOFA) score, RT-PCR of oro-nasopharyngeal swabs, the severity of ARDS on the day of tocilizumab admission, time from RT-PCR positivity to tocilizumab administration, respiratory support treatments, all other medical treatments, and ICU outcomes were recorded. Risk factors affecting mortality were evaluated with multiple regression analysis. Results: A total of 60 patients with a median age of 69.8 (24-87) years, 25 females and 35 males were included in the study. The mean APACHE II score was 18.9 ± 8.0, and the SOFA score was 4.5 ± 2.0. Fifty-two (86.7%) patients had positive oro-nasopharyngeal swabs for SARS-CoV-2 by RT-PCR; (13,3%) patients had positive IgM/Ig G rapid antibody tests for SARS-CoV-2. Tocilizumab was given on an average of 2.5th days (± 2.0 days). On the day of tocilizumab administration, 1 (1.7%) patient had mild ARDS, 30 (50.0%) had moderate ARDS, and 29 (48.3%) had severe ARDS. The PaO2/FIO2 ratio of the study group on the day of tocilizumab administration was 96.7 ± 36.6 mmHg. Thirty-four (56.7%) patients were intubated during follow-up. Forty (66.7%) patients died, while 20 (33.3%) patients were transferred to the ward. The mean length of stay in the ICU was 11.4 ± 5.5 days. Advanced age (Hazard ratio (HR) 1.8; 95% confidence interval (CI) 0.88-0.93; p < 0.001), higher APACHE II score (HR 0.81, 95% CI 0.74-0.98; p = 0.001), higher SOFA score on the day of tocilizumab administration (HR 1.47, 95% CI 0.39-0.79; p = 0.001), and lower PaO2/FIO2 ratio (HR 2.54, 95% CI 2.33-3.79; p < 0.001) were determined as independent risk factors for mortality. Conclusion: Patients administered tocilizumab and favipiravir in our ICU were mostly patients with moderate-severe ARDS and had higher inflammatory markers. The reason for the high mortality in this study was attributed to the fact that all of the patients had moderate-severe COVID-19-related ARDS, rather than severe COVID-19.