The effect of nitrous oxide and carbon dioxide pneumoperitoneum on operative and postoperative pain during laparoscopic sterilization under local anesthesia.

Study Objective: To compare carbon dioxide and nitrous oxide pneumoperitoneum with respect to intraoperative and postoperative pain during laparoscopic sterilization under local anesthesia.
Design: Randomized, double-blind study of pain during surgery and at 15 minutes, 1 hour, and 24 hours postoperatively.
Setting: Regional Medical Center, Memphis, Tennessee.
Patients: Women scheduled for laparoscopic sterilization under local anesthesia. Interventions. Forty-nine patients were randomized to carbon dioxide and 56 to nitrous oxide pneumoperitoneum.
Measurements and Main Results: Pain was assessed using a modified McGill pain questionnaire. Intraoperative pain was measured by the amount of supplemental narcotic required. Analgesic use in the recovery room and during the first 24 hours postoperatively was compared. Demographics for both groups were similar. The groups had no statistical differences in pain during surgery or at any of the postoperative time periods. Recovery room analgesia requirement was similar, but the nitrous oxide group used fewer pain tables (0.98 vs 0.42 tablets) in the first 24 hours.
Conclusions: There is no difference in intraoperative and postoperative pain between nitrous oxide and carbon dioxide pneumoperitoneum for laparoscopic sterilization when used in conjunction with a protocol such as ours.