Supplemental oxygen does not prevent postoperative nausea and vomiting after gynecological laparoscopy

Postoperative nausea and vomiting are among the most common and distressing side effects of general anesthesia. Supplemental intraoperative 80% oxygen reduces postoperative nausea and vomiting following open and laparoscopic abdominal surgery. However, this benefit has not been observed in other patient populations. We undertook this study to evaluate the effect of 80% supplemental intraoperative oxygen on the incidence of postoperative nausea and vomiting following ambulatory surgery for laparoscopic tubal ligation.

Following Research Ethics Board approval, 304 subjects were enrolled into one of two arms of a randomized prospective controlled study. The intervention group (n = 147) breathed 80% oxygen and the control group (n = 145) breathed routine 30% oxygen (balance medical air) while both groups were receiving a standardized general anesthetic. Nausea was assessed as: none, mild, moderate, or severe; vomiting was any emetic episode or retching. Any assessment either greater than none (nausea) or greater than zero (vomiting) was considered positive.

The incidence of postoperative nausea and vomiting up to 24 hr following surgery was 69% in the 80% oxygen intervention group and 65% in the 30% oxygen control group (P = 0.62). There were no differences in nausea alone, vomiting, or antiemetic use in the postoperative anesthetic care unit or at any time (pre- or post-discharge) up to 24 hr after surgery.

This trial of 304 women did not demonstrate that administering intraoperative supplemental 80% oxygen during ambulatory surgery for laparoscopic tubal ligation prevented postoperative nausea or vomiting during the initial postoperative 24 hr compared with women who received routine 30% oxygen.