Central Venous to Arterial Partial Pressure of Carbon Dioxide (pCO2) gradient as A Complementary Tool to Serum Lactate as A Marker for Improvement of Sepsis

Background: Severe organ failure due to an uncontrolled immune response to infection is known as sepsis. Sepsis is becoming more common and poses a challenge for emergency physicians due to its complex pathophysiology, genetics, and clinical manifestations. It is a substantial global burden. Aim: In order to find out how useful the pCO2 gradient from the central veins to the arterial blood is for treating sepsis, in addition to serum lactate. Subjects and methods: From September 2024 through June 2025, 42 patients were enrolled in this prospective cohort study situated in the medical intensive care unit of the Al-Hussein University Hospital of Al-Azhar University in Cairo, Egypt. Results: Because MAP is lower in the high-gap group, a statistically significant relationship between MAP and the partial pressure of carbon dioxide gap was observed immediately after the first day of admission and continued throughout the length of the investigation. By the end of the sixth hour following enrollment, the usual gap group had significantly lower lactate levels. Central venous oxygen saturation and partial pressure of carbon dioxide gap were shown to have a non-significant association among the cases analyzed, which is an interesting finding. Conclusion: The current study found that monitoring improvement in septic patients may require more than just aiming for a central venous oxygen saturation level above 70%. Having a high central venous to arterial partial CO2 pressure during early resuscitation is linked to worse outcomes, higher lactate concentrations, lower mean arterial pressure, and more multi-organ dysfunction. Therefore, it may be helpful to combine the partial pressure of carbon dioxide gap with central venous oxygen saturation to gain more insight into hemodynamics and the ability to clear lactate.