Role of Interleukin 6 and C-Reactive Protein Levels in Predicting the Need for Mechanical Ventilation in COVID 19 Patients

Abstract Background COVID-19 is caused by coronavirus; first discovered in China 2019, COVID-19 infection shows symptoms ranging from influenza like symptoms; fever, sore throat, headache, cough and dyspnea to marked respiratory distress manifestations like dyspnea, hypoxia, tachypnea and disturbed conscious level lastly to death Objective As severe symptoms are related to increased inflammatory markers. So the aim is to assess the correlation between levels of IL6, CRP and other inflammatory markers as predictors and the need for mechanical ventilation. Methods A retrospective analytical cohort study was performed on twenty-five patients admitted to critical care department with COVID-19 positive reverse transcription polymerase chain reaction (PCR) over last 3 years. Patients’ data collected from the critical care department port- Fouad hospital and Ain Shams University Hospital. Labs and vital signs were collected at day 0 and day 3 of admission and patients were divided into two groups. Results The higher the levels of IL6 and CRP the more severe are the symptoms. The study showed higher IL6 levels in group II with (mean 238±169.79) as compared to group I (mean 49.18 ± 56.18) with significant p value 0.001. CRP in mechanically ventilated patients (group II) showed higher values (mean 176.54±51.69) than other patients who didn’t need mechanical ventilation (mean 69.42±23.56). with significant p value < 0.001. Variables found to be statistically significant related to outcome. The values correlate well with the need to mechanical ventilation, as the higher the CRP and IL-6 value the increased need to mechanical ventilation. It also correlates with longer length of stay in intensive care unit and increasing mortality of high-risk group. Conclusion Through studying the levels of IL-6 and CRP in patients admitted to ICU due to COVID-19 infection; who were classified to 2 groups the first needed mechanical ventilation and the other group did not, it was noticed that higher levels of IL-6 and CRP are strong predictors for the need of mechanical ventilation with cut off value 120 for CRP and 151 for IL-6. They also were a strong predictor for mortality and increased ICU -LOS, as the higher levels of circulating inflammatory markers and cytokine (cytokine storm) was associated with a higher risk of mortality and increase LOS in ICU.