High Central Venous Oxygen Saturation and Elevated Serum Lactate in Septic Shock: A Marker of Impaired Oxygen Utilization

Background:Septic shock is a life-threatening condition characterized by circulatory and metabolic abnormalities, where timely recognition of impaired tissue oxygenation is essential for effective resuscitation. Central venous oxygen saturation (ScvO) is commonly used as a surrogate marker of oxygen balance; however, its reliability as a standalone indicator in sepsis remains controversial. Lactate levels are often used to detect occult hypoperfusion, and the role of arterial oxygen saturation (SaO) in this context is unclear. Objectives: To evaluate the correlation between ScvO, Sa, and serum lactate levels in patients with septic shock, and assess the utility of combined monitoring for guiding resuscitation. Conclusion:Our findings demonstrated that high ScvO values in septic shock may reflect impaired oxygen extraction rather than adequate perfusion, as indicated by associated elevated serumlactate levels. SaO does not correlate with tissue perfusion markers. These findings support the use of combined ScvO andserum lactate monitoring for better evaluation of oxygenation and guide resuscitation in septic shock.