Surgical Position and Hemodynamics in PCNL

This prospective clinical trial investigates the hemodynamic effects of different surgical positions-supine, lithotomy, and prone-in patients undergoing percutaneous nephrolithotomy (PCNL). The study evaluates hemodynamic variables both in the awake state and under general anesthesia to distinguish the individual and combined impacts of anesthesia and patient positioning on cardiovascular function. Hemodynamic measurements are performed using the Pressure Recording Analytical Method (PRAM), a minimally invasive technique that allows continuous assessment of parameters such as mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), pulse pressure variation (PPV), stroke volume variation (SVV), stroke volume index (SVI), cardiac contractility parameters (dP/dtmax), arterial elastance (Ea), cardiac power index (CPI), and cardiac cycle efficiency (CCE). Each patient is sequentially positioned in the three surgical positions while awake, and the same measurements are repeated after the induction of general anesthesia in the corresponding positions. The primary aim is to determine how surgical positioning under general anesthesia alters key cardiovascular parameters. Secondary objectives include comparing hemodynamic changes across positions in both conscious and anesthetized states, identifying potential risks associated with specific positions, and guiding intraoperative patient management to improve safety and outcomes in PCNL procedures. The study is conducted at a single center and includes adult patients with ASA physical status I-II scheduled for elective PCNL surgery. The findings are expected to provide valuable data for anesthesiologists and surgeons to optimize perioperative cardiovascular stability, particularly during position changes in urological surgeries.