Effect of Perioperative Oxygen Supplementation on 30-day Surgical Site Infection Rate in Abdominal, Gynecologic, and Breast Surgery The ISO 2 Randomized Controlled Trial Pascal Thibon, M.D., M.Sc.,* France Borgey, M.D., M.Sc.,* Se ´ bastien Boutreux, M.D., M.Sc.,† Jean-Luc Hanouz, M.D., Ph.D.,‡ Xavier Le Coutour, M.D., Ph.D.,§ Jean-Jacques Parienti, M.D., Ph.D. ABSTRACT Background: Benefits and limitations of supplementation with 80% fraction of inspired oxygen for preventing surgical site infections have not yet been clearly defined. Some studies have reported benefits in colorectal surgery, whereas trials in abdominal and gynecologic surgery have reported either no effect or a deleterious effect. Methods: Controlled, randomized, assessor-blind multi- center trial, the ISO 2 study, comparing the effects of hyper- oxygenation (fraction of inspired oxygen, 80%) with those of 30% oxygen on the frequency of surgical site infections in routine abdominal, gynecologic, and breast surgery on 434 patients. Patients not seen in consultation after discharge were contacted. Results: In total, 208 patients received 30% perioperative oxygen and 226 received 80%. There was no difference be- tween the two groups for baseline, intraoperative, and post- operative characteristics, except for oxygen saturation at clo- sure, higher in the 80% group (P = 0.01). The frequency of 30-day surgical site infections was 7.2% (15/208) in the 30% group and 6.6% (15/226) in the 80% group (relative risk, 0.92; 95% CI [0.46 –1.84], P = 0.81). Frequency of adverse events (nausea and vomiting, sternal pain, cough, hypoten- sion) was similar in the two groups. Desaturation and brady- cardia were more frequent in the 30% group. In an updated meta-analysis including the result of this trial and those of eight published randomized trials, the overall relative risk was 0.97; 95% CI (0.68 –1.40), I 2 (inconsistency degree) = 73%, (P = 0.88). Conclusions: The routine use of hyperoxygenation through- out abdominal, gynecologic, and breast surgery had no effect on the frequency of 30-day surgical site infections and was not accompanied by more frequent adverse effects. S URGICAL-SITE infections (SSI) are frequent, poten- tially serious, and costly. 1–3 The fight against such infec- tions is a daily concern of surgical, anesthesiology, and infec- tion control teams. The risk factors for SSI are related to the characteristics of the patients, the surgical procedures carried out, and perioperative conditions. Scientific societies have issued recommendations 4 for reducing the risk of SSI. In addition to major preoperative prevention measures (antibi- otic prophylaxis and preparation of the skin of the patient undergoing surgery), these recommendations include impor- * Staff Infection Control Physician and Epidemiologist, Antenne Re ´gionale de Lutte contre les Infections Nosocomiales de Basse- Normandie, ‡ Staff Anesthesiologist, Professor of Anesthesiology and Critical Care, Department of Anesthesiology and Intensive Care, § Staff Infection Control Physician and Epidemiologist, Antenne Re ´gionale de Lutte contre les Infections Nosocomiales de Basse- Normandie, and Staff Infection Control Physician, Professor of Pub- lic Health, Department of Infection Control,  Staff Methodologist, Associate Professor of Biostatistics, Department of Biostatistic and Clinical Research, Caen University Hospital, Caen, France. † Staff Epidemiologist, Unit of Medical Information and Public Health, Pe ´rigueux Hospital Center, Pe ´rigueux, France. Received from Antenne Régionale de Lutte contre les Infections Nosocomiales de Basse-Normandie, Centre Hospitalier Universitaire de Caen, Caen, France. Submitted for publication September 19, 2011. Accepted for publication May 14, 2012. Supported by a French government grant from the Programme Hospitalier de Recherche Clinique, as well as additional funding from Centre de Coordination de la Lutte contre les Infections Nosocomiales Ouest, Rennes, France, and AIR-LIQUIDE Sante ´, Paris, France. Address correspondence to Dr. Thibon: Antenne Régionale de Lutte contre les Infections Nosocomiales de Basse-Normandie, Cen- tre Hospitalier Universitaire de Caen, 14033 Caen Cedex 9, France. thibon-p@chu-caen.fr. Information on purchasing reprints may be found at www.anesthesiology.org or on the masthead page at the beginning of this issue. ANESTHESIOLOGY’s articles are made freely accessible to all readers, for personal use only, 6 months from the cover date of the issue. Copyright © 2012, the American Society of Anesthesiologists, Inc. Lippincott Williams & Wilkins. Anesthesiology 2012; 117:504 –11 What We Already Know about This Topic • There are conflicting results regarding the effect of high quan- tities of oxygen utilized perioperatively on preventing surgical site infections What This Article Tells Us That Is New • Routine delivery of 80% FiO 2 in abdominal, gynecologic, and breast surgery did not decrease the incidence of 30-day sur- gical site infections Anesthesiology, V 117 • No 3 September 2012 504 Downloaded from anesthesiology.pubs.asahq.org by guest on 06/05/2020