A randomized, prospective comparison of end-tidal CO2 pressure during laparoscopic cholecystectomy in low and high flow anesthetic system.

Background: Low flow anaesthesia has been used in anesthetic practice to prevent operation room pollution and also for econormical reasons. Since the safety of low flow technique has not been clearly determined in previous researches this study was performed to compare the end-tidal CO2 pressure during laparoscopic cholecystectomy in low flow as opposed to high flow anesthesia.

Methods: Forty patients, 30-65 years of age, ASA physical status I or II, scheduled for laparoscopic cholecystectomy under general anesthesia were randomly alloted to low flow and high flow groups. End-tidal CO2 pressure, arterial blood pressure, pulse oximetric oxygen saturation, and heart rate were measured before, during and after insufflation of CO2 into the peritoneal cavity. The data were compared between two groups.

Results: Pneumoperitoneum caused a decrease in PaO2 and oxygen saturation together with increases in PaCO2 and end-tidal CO2 pressure in both groups but the differences between two groups were not statistically significant.

Conclusions: The result of this study shows that end-tidal CO2 pressure during laparoscopic cholecystectomy using low flow anesthesia system is comparable to that with high flow system. Therefore it can be concluded that low flow anesthesia can be used with relative safety in anesthetic management of patients during laparoscopic cholecystectoy.