Do dynamic changes in haematological and biochemical parameters predict mortality in critically ill COVID-19 patients?

Background: Critically ill COVID-19 patients are usually subjected to clinical, laboratory, and radiological diagnostic procedures resulting in numerous findings. Utilizing these findings as indicators for disease progression or outcome prediction is particularly intriguing.

Objectives: Exploring the significance of dynamic changes in haematological and biochemical parameters in predicting the mortality of critically ill COVID-19 patients.

Methods: The present study was a prospective and observational study involving mechanically ventilated 75 critically ill adult COVID-19 patients with hypoxemic respiratory failure. The collected data included baseline patient characteristics, treatment options, outcome, and laboratory findings at admission and 7 days after. The dynamics of the obtained findings were compared between survivors and non-survivors.

Results: The 28-day survival rate was 61.3%. In the group of non-survivors significant dynamic changes were found for C-reactive protein (p= 0.001), interleukin-6 (p< 0.001), lymphocyte (p= 0.003), neutrophil-lymphocyte ratio (p= 0.003), platelets (p< 0.001), haemoglobin (p< 0.001), iron (p= 0.012), and total iron-binding capacity (p< 0.001). Statistically significant changes over time were found for ferritin (p= 0.010), D-dimer (p< 0.001), hs-troponin T (p< 0.002), lactate dehydrogenase (p= 0.001), glucose (p= 0.023), unsaturated iron-binding capacity (p= 0.008), and vitamin D (p< 0.001).

Conclusion: The dynamic changes in inflammatory, haematological and biochemical parameters can predict disease severity, and outcome.