[The effects of propofol anesthesia with or without the use of nitrous oxide on the intraoperative involuntary movement, the postoperative awareness and vomiting].

The authors investigated the effect of anesthesia with nitrous oxide and propofol on intraoperative involuntary movement, muscle relaxant usage, postoperative nausea and vomiting, the total amount of propofol used, and recovery time from anesthesia. Eighty-eight patients for gynecological surgery were randomly divided into group PE: propofol/epidural (n = 44), and group PEG: propofol/epidural/nitrous oxide (n = 44). The frequency of postoperative nausea and vomiting were assessed at 24-h postoperatively by blinded observers. There were significant decreases of the mean amounts of propofol and muscle relaxant used between group PEG and group PE. The authors found no correlation between the use of nitrous oxide and intraoperative involuntary movement, subsequent development of postoperative quality of awareness, recovery time, nausea and vomiting. We recommend PEG method for gynecological surgery rather than PE from an economical viewpoint because it is associated with the reduction of mean propofol and muscle relaxant used.