The Effects Of Carbon Dioxide Pneumoperitoneum And Body Position On Intraocular Pressure In Laparoscopic Surgical Patients Under Intravenous Anesthesia

Objective To investigate the effects of carbon dioxide pneumoperitoneum and body position on intraocular pressure in laparoscopic surgical patients under intravenous anesthesia.Methods 18 patients undergoing laparoscopic pelvic surgeries scheduled position head-down and 18 patients undergoing laparoscopic cholecytectomies scheduled position head-up were randomly enrolled into the present study. Propofol and fentany were used for anesthesia induction, and propofol / remifentanil for anesthesia maintenance. Rocuronium was used for muscle relaxant. The IOP was measured before surgery as baseline, 5 minutes after anesthesia induction, 5 minutes after CO₂ pneumoperitoneum, 30-35 minutes after body position changed and CO₂ pneumoperitoneum, and after P_ETCO₂ regulated to normal levels.Results The IOP dropped manifestly after intravenous anesthesia induction in both groups and kept almost unchanged 5 minutes after CO₂ pneumoperitoneum. The IOP rose 5 minutes after the patients were positioned head down, and gradually increased over the baseline 30-35 minutes after the patient's position changed and CO₂ pneumoperitoneum. After respiratory parameters regulated and P_ETCO₂ decreased to normal level, the IOP gradually decreased below level of baseline, but still higher than that after anesthesia induction. However in the patients with position head up, the IOP gradually increased over the level after anesthesia induction 30-35 minutes after the patient's position changed and CO₂ pneumoperitoneum, but still less than that of baseline. After respiratory parameters regulated and P_ETCO₂ decreased to normal level, the IOP dropped a bit, but still lie between the baseline and the level after induction of anesthesia. Changes of IOP in both groups were positively correlated with PETCO₂.Conclusion Induction of anesthesia with propofol and fentanyl can lower IOP. CO₂ pneumoperitoneum and high level P_ETCO₂ can raise IOP especially in patients with position head down. If P_ETCO₂ was regulated to normal level, IOP could be controlled under baseline.