Pneumoperitoneum Duration and Bicarbonate Changes in Laparoscopic Hernia Surgery

Carbon dioxide pneumoperitoneum is routinely used during laparoscopic surgery to provide adequate visualization and working space. However, absorption of carbon dioxide and increased intra-abdominal pressure may influence acid-base balance during the perioperative period. These physiological changes may be reflected in blood gas parameters such as pH, partial pressure of carbon dioxide (pCO2), and serum bicarbonate levels. This prospective observational study aims to evaluate the relationship between pneumoperitoneum duration and perioperative changes in serum bicarbonate levels in patients undergoing laparoscopic inguinal hernia repair using the transabdominal preperitoneal (TAPP) technique. Adult patients undergoing elective laparoscopic inguinal hernia repair will be included in the study. Blood gas measurements will be obtained before surgery and at the second postoperative hour. Serum bicarbonate levels will be recorded, and the difference between preoperative and postoperative measurements (ΔHCO3-) will be calculated. The primary outcome of the study is the change in serum bicarbonate levels between the preoperative and postoperative second-hour measurements. Secondary outcomes include postoperative pain scores, postoperative acid-base parameters such as pH and pCO2, and early postoperative complications within the first 24 hours. Pneumoperitoneum duration will be recorded intraoperatively and analyzed for its association with perioperative metabolic changes. The findings of this study may contribute to a better understanding of metabolic alterations occurring during laparoscopic surgery and their potential clinical implications.