Intravascular Volume Status

This study aims to evaluate perioperative hemodynamic changes using the inferior vena cava (IVC) collapsibility index in patients undergoing lumbar stabilization surgery under general anesthesia. The IVC diameter and collapsibility index will be measured using ultrasonography at predefined perioperative time points. Hemodynamic parameters such as blood pressure and heart rate will also be recorded. The study seeks to determine whether the IVC collapsibility index can be used as a non-invasive indicator of intravascular volume status and hemodynamic changes during lumbar spine surgery.