Prognostic markers in patients with COVID-19 requiring intensive care support

Several hematological and immunological markers, particularly neutrophil count, predict the severity of COVID-19. This study aimed at assessing hematological and coagulation parameters at different time points, to predict the complications or outcomes of patients with COVID-19 admitted to the intensive care unit (ICU).

We conducted a prospective observational multicenter study in ICU departments. A total of 118 patients with COVID-19 admitted to the ICU were included. Clinical data and blood samples from routine hematology and coagulation tests were collected at admission, and on days 3, 7, and 14. The main outcome measures were high-flow-O₂ requirement, thrombosis, and 30-day mortality.

The venous thromboembolism score increased from a mean of 5.10 ± 2 on day 0 to 6.40 ± 2.80 on day 14 (P = 0.0002). The disseminated intravascular coagulation (DIC) score significantly correlated with thrombosis (P = 0.031). A total of 41.20% of patients in the ICU had a DIC score ≥4, and 11.40% had a score <4. Mortality was negatively associated with patients on high-flow O₂, 9 patients (10.80%) (P = 0.040), and positively associated with patients receiving ventilation, 16 patients (27.50%) (P < 0.001). An increase in white blood cell count (subdistribution hazard ratio (SHR): 0.91; 95% CI: 0.80-1) and neutrophil count (SHR: 1; 95% CI: 1.01-1.05) was associated with greater disease severity and D-dimer level (SHR: 1.60; 95% CI: 1.10-2.5).

The venous thromboembolism score was significantly higher for patients who died than those who recovered. Furthermore, mechanical ventilation was associated with high mortality, whereas the risk of thrombosis and ICU admission correlated with high D-dimer values and DIC scores. Therefore, D-dimer levels and DIC scores are prognostic markers that may predict disease severity in patients with COVID-19.