Factors Associated with Mortality among COVID-19 Patients Admitted in an Intensive Care Unit at a Tertiary Care Setting: A Retrospective Study from Mizoram, India

Introduction: Characteristics of Coronavirus Disease-2019 (COVID-19) patients from different tertiary centres in India are beginning to be enumerated with limited data on critically ill patients admitted in Intensive Care Units (ICU), with low SpO2 levels.

Aim: To describe clinical profile and identify the factors associated with mortality among COVID-19 positive patients admitted in ICU at a tertiary care setting in Mizoram, India.

Materials and Methods: A retrospective study was conducted in Zoram Medical College, Mizoram, India, among 55 confirmed COVID-19 patients admitted in ICU between March 2020 and March 2021. All the patients admitted in ICU during the period was included in the study. Demographic data, symptoms, co-morbidity, investigations, ventilation required, treatment given, duration of ICU stay, and outcomes were recorded from case sheets. The primary outcome was inpatient mortality. Secondary outcomes included length of ICU stays, SpO2 levels, need for oxygen support. The p-value was set at <0.05 analysed using coGuide software.

Results: The mean age was 56.47±15.24 years, and 38 (69.1%) participants were males. Most of 45 (81.8%) participants survived, and 10 (18.2%) patients died in ICU. The mean length of ICU stay was 7 (4 to 13) days in the survival group and 13 (7.5 to 17) for non survivors. The mean SpO2 levels at the time of admission were 95% (90 to 97) in survivors and 80% (72.25 to 95.50) among non survivors. Following admission to ICU, 16 (29.1%) patients required intubation, High Flow Nasal Cannula (HFNC) was given to 2 (3.6%), and oxygen support (non rebreather mask) was required in all 55 (100%) patients. Pharmacological treatment included empiric antibiotics in 51 (92.73%), antiviral in 30 (54.55%), steroids in 45 (81.8%), Ivermectin in 21 (38.2%), and low molecular weight heparin in 36 (65.5%) patients. Binary logistic regression analysis found low SpO2 levels at the time of admission (CI:0.85-0.97, p-value=0.008), hypotension (p-value <0.001), tachycardia (p-value=0.001), use of remdesivir (odds ratio 14.82, 95% CI:1.72 to 127.52), use of tocilizumab (odds ratio 14.33, 95% CI: 2.14 to 95.85) and use of meropenem (odds ratio 8.00, 95% CI: 1.51 to 42.45) were significantly associated with in-hospital mortality.

Conclusion: Oxygen saturation below 90%, hypotension, and tachycardia, at the time of admission in ICU were considered as predictors of in-hospital ICU mortality in COVID-19 patients. The reason for low mortality among patients admitted in ICU can be attributed to early admission to ICU and care when SpO2 reading has reached 94%.