Effects of perioperative oxygen concentration on oxidative stress in adult surgical patients: a systematic review

Abstract

Background: The fraction of inspired oxygen (FiO 2) administered during general anaesthesia varies widely despite international recommendations to administer FiO 2 0.8 to all anaesthetised patients to reduce surgical site infections (SSIs). Anaesthetists remain concerned that high FiO 2 administration intraoperatively may increase harm, possibly through increased oxidative damage and inflammation, resulting in more complications and worse outcomes. In previous systematic reviews associations between FiO 2 and SSIs have been inconsistent, but none have examined how FiO 2 affects perioperative oxidative stress. We aimed to address this uncertainty by reviewing the available literature. Methods: EMBASE, MEDLINE, and Cochrane databases were searched from inception to March 9, 2020 for RCTs comparing higher with lower perioperative FiO 2 and quantifying oxidative stress in adults undergoing noncardiac surgery. Candidate studies were independently screened by two reviewers and references hand-searched. Methodological quality was assessed using the Cochrane Collaboration Risk of Bias tool. Results: From 19 438 initial results, seven trials (n¼422) were included. Four studies reported markers of oxidative stress during Caesarean section (n¼328) and three reported oxidative stress during elective colon surgery (n¼94). Risk of bias was low (four studies) to moderate (three studies). Pooled results suggested high FiO 2 was associated with greater malondialdehyde, protein-carbonyl concentrations and reduced xanthine oxidase concentrations, together with reduced antioxidant markers such as superoxide dismutase and total sulfhydryl levels although total antioxidant status was unchanged. Conclusions: Higher FiO 2 may be associated with elevated oxidative stress during surgery. However, limited studies have specifically reported biomarkers of oxidation. Given the current clinical controversy concerning perioperative oxygen therapy, further research is urgently needed in this area.

Midazolam Ameliorates Acute Liver Injury Induced by Carbon Tetrachloride via Enhancing Nrf2 Signaling Pathway

“…More and more attention has been paid to the methods of reducing perioperative oxidative stress, such as endoscopic surgery (Arsalani-Zadeh et al, 2011), reducing the concentration of inhaled oxygen (Oldman et al, 2021) and giving antioxidant drugs (Ali-Hasan-Al-Saegh et al, 2016) and other methods. However, due to the limitations of surgical methods and patients' own conditions, the clinical application of the first and second method are limited.…”

Postoperative Supplemental Oxygen in Liver Transplantation (PSOLT) does not reduce the rate of infections: results of a randomized controlled trial

“…Hyperoxygenation was reported to aggravate oxidative stress [26,43,44]. This seems to be responsible for the observed clinical outcomes, such as increased longterm mortality of cancer patients, shorter cancer-free survival, and increased mortality of acutely ill patients [45][46][47].…”

“…Considering the previously reported benefits of high FiO 2 in patients undergoing higher risk colorectal procedures and complete lack of data regarding patients undergoing LT, the latter seem of particular interest in evaluating the effects of perioperative hyperoxygenation. Further, increased formation of reactive oxygen species (ROS) secondary to hyperoxia may not only facilitate elimination of pathogens, but may also exacerbate the process of oxidative stress [ 26 ]. In LT, this may translate into higher degree of ischemia-reperfusion injury with potential negative effects on clinical outcomes [ 27 , 28 ].…”

Hydrogen-oxygen therapy improves postoperative pulmonary functions and accelerates recovery through attenuating inflammatory reactions and oxidative stress in patients undergoing lung surgery

“…Postoperatively, these patients frequently receive oxygen therapy. However, although oxygen therapy can provide oxygen to the patients, it may also induce detrimental outcomes, such as increased oxidative stress [7].…”