In patients with sepsis who are treated in the intensive care unit under invasive mechanical ventilation, the combined evaluation of ScvO₂ and PcvCO₂ may provide a comprehensive insight into tissue oxygenation and metabolic stress, allowing a more precise hemodynamic assessment in critically ill patients. The aim of this study is to evaluate the monitoring of ScvO₂, PcvCO₂, and EtCO₂ in intensive care patients in order to predict hemodynamic instability, 28-day mortality, and length of ICU stay, as well as to investigate their effects on cardiac output, tissue oxygenation, and hypoperfusion.