Effect of Intraoperative High Inspired Oxygen Fraction on Surgical Site Infection, Postoperative Nausea and Vomiting, and Pulmonary Function Systematic Review and Meta-analysis of Randomized Controlled Trials

Background: Intraoperative high inspired oxygen fraction (Fio(2)) is thought to reduce the incidence of surgical site infection (SSI) and postoperative nausea and vomiting, and to promote postoperative atelectasis. Methods: The authors searched for randomized trials (till September 2012) comparing intraoperative high with normal Fio(2) in adults undergoing surgery with general anesthesia and reporting on SSI, nausea or vomiting, or pulmonary outcomes. Results: The authors included 22 trials (7,001 patients) published in 26 reports. High Fio(2) ranged from 80 to 100% (median, 80%); normal Fio(2) ranged from 30 to 40% (median, 30%). In nine trials (5,103 patients, most received prophylactic antibiotics), the incidence of SSI decreased from 14.1% with normal Fio(2) to 11.4% with high Fio(2); risk ratio, 0.77 (95% CI, 0.59-1.00). After colorectal surgery, the incidence of SSI decreased from 19.3 to 15.2%; risk ratio, 0.78 (95% CI, 0.60-1.02). In 11 trials (2,293 patients), the incidence of nausea decreased from 24.8% with normal Fio(2) to 19.5% with high Fio(2); risk ratio, 0.79 (95% CI, 0.660.93). In patients receiving inhalational anesthetics without prophylactic antiemetics, high Fio(2) provided a significant protective effect against both nausea and vomiting. Nine trials (3,698 patients) reported on pulmonary outcomes. The risk of atelectasis was not increased with high Fio(2). Conclusions: Intraoperative high Fio(2) further decreases the risk of SSI in surgical patients receiving prophylactic antibiotics, has a weak beneficial effect on nausea, and does not increase the risk of postoperative atelectasis.