Changes in arterial blood gases and arterial pressure during laparoscopic cholecystectomy under the general anesthesia (enflurane in N2O/O2 50%) were investigated in 30 patients, who were divided into two groups according to control of minute
ventilation.
During surgery, Minute ventilation was set 100㎖/kg in group I and 150㎖/kg in group II, and intraabdominal pressure was maintained at 15mmHg by CO2 insufflation. In both groups. Variables were measured before CO2 gas insufflation. 15 and 30
minutes
after insufflation, just after exsufflation, 15 and 30 minutes after exsufflation and in recovery room.
1. PaCO2 was increased significantly during Co2 gas insufflation and just after exsufflation in both group, and degree of increase (PaCO2) was significantly greater in group I compared to group II.
2. Changes of PaO2 were not statistically significant in comparison to control value and between two groups during CO2 gas insufflation and exsufflation.
3. Blood pH in both groups were lowered significantly compared to control value during CO2 gas insufflation and exsufflation, and group II (increased minute ventilation group), represents lower risk of acidosis compared to group I.
4. Mean arterial pressure and airway pressure were significantly increased compared to control value during CO2 gas insufflation, but there was no significant difference between two groups.
These results suggest that minute ventilation during laparoscopic cholecystectomy should be increased up to maintaining normal PaCO2 for prevention of hemodynamic and blood gas changes due to CO2 retention.
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