Pv-aCO₂ Gap-Guided Resuscitation in Adult Polytrauma Patients: A Prospective Randomized Controlled Trial

dult patients with multiple traumatic injuries admitted to the ICU from the operating room, emergency department, or hospital wards who meet the study criteria will be included after obtaining informed consent from the patient or their legal guardian. Participants will be randomly divided into two groups: one group will receive treatment guided by the difference between carbon dioxide levels in venous and arterial blood, while the other group will receive treatment based on standard resuscitation parameters commonly used in critical care. As part of routine monitoring, all patients will have a central venous catheter and an arterial line inserted to measure blood parameters. Blood samples from both lines will be taken shortly after ICU admission and at regular intervals during the first three days. These samples will be analyzed using a bedside blood gas machine, and the results will be compared between the two groups to determine whether monitoring the difference in carbon dioxide levels between venous and arterial blood improves patient outcomes compared with standard care.

All polytrauma patients admitted to the ICU from the operating theater, emergency department, or hospital wards who fulfill the inclusion criteria will be enrolled in the study after obtaining written informed consent from the patients or their legal representatives. Participants will be randomized in a 1:1 ratio using a computer-generated method into two groups: an intervention group managed with a Pv-aCO₂ gap-targeted approach and a control group managed according to standard resuscitation end-points. As part of routine hemodynamic monitoring in critical care, a central venous catheter (two- or three-lumen catheter-Arrow) and an arterial catheter (Arterial Leader Cath-Vygon or Teleflex) will be inserted in all participants before or immediately after ICU admission. After insertion, the position of the central venous catheter tip at the junction of the superior vena cava and right atrium will be confirmed by chest X-ray. Arterial and venous blood samples for blood gas analysis (ABGA and VBGA) will be obtained in the ICU using a point-of-care gas analyzer (ABL800 FLEX®, Radiometer) within 1 hour of ICU admission and subsequently at 6, 12, 24, 48, and 72 hours. The time interval between arterial and venous blood sampling will be kept under 5 minutes to minimize bias, and the measurements obtained at different time points will be compared with standard resuscitation end-points.