REVIEW   Free access

Minerva Anestesiologica 2020 January;86(1):64-75

DOI: 10.23736/S0375-9393.19.13906-5

Copyright © 2019 EDIZIONI MINERVA MEDICA

lingua: Inglese

Hyperoxia and oxidative stress in anesthesia and critical care medicine

Sara OTTOLENGHI ¹ ✉, Giovanni SABBATINI ², Andrea BRIZZOLARI ^{1, 3}, Michele SAMAJA ¹, Davide CHIUMELLO ^{1, 2, 4}

¹ Department of Health Science, University of Milan, Milan, Italy; ² Department of Anesthesia and Intensive Care, San Paolo University Hospital, ASST Santi Paolo e Carlo, Milan, Italy; ³ DAN Europe Research Division, Roseto degli Abruzzi, Teramo, Italy; ⁴ Coordinated Research Center on Respiratory Failure, University of Milan, Milan, Italy

Oxygen administration is particularly relevant in patients undergoing surgery under general anesthesia and in those who suffer from acute or critical illness. Nevertheless, excess O2, or hyperoxia, is also known to be harmful. Toxicity arises from the enhanced formation of reactive oxygen species (ROS) that, exceeding the antioxidant defense, may generate oxidative stress. Oxidative stress markers are used to quantify ROS toxicity in clinical and non-clinical settings and represent a promising tool to assess the optimal FiO2 in anesthesia and critical care setting. Despite controversial, the guidelines for the regulation of FiO2 in such settings suggest the adoption of high perioperative oxygen levels. However, hyperoxia has also been shown to be an independent mortality risk factor in critically ill patients. In this literature review, we discuss the biochemical mechanisms behind oxidative stress and the available biomarkers for assessing the pro-oxidant vs antioxidant status. Then, we summarize recent knowledge on the hyperoxia-related consequences in the most common anesthesia and critical care settings, such as traumatic brain injury or cardiac arrest. To this purpose, we searched the PubMed database according to the following combination of key words: (“hyperoxia” OR “FiO2” OR “oxygen therapy”) AND (“oxidative stress” OR “ROS” OR “RNS” OR “lipid peroxidation”) AND (“anesthesia” OR “surgery” OR “intensive care”). We focused in the results from the past 20 years. Available evidence points toward a conservative monitoring and use of oxygen, unless there is solid proof of its efficacy.

KEY WORDS: Hyperoxia; Oxidative stress; Anesthesia; Critical care; Oxygen consumption