Cardiac protection by volatile anesthetics in non-cardiac surgery? A meta-analysis of randomized controlled studies on clinically relevant endpoints

INTRODUCTION: Volatile anesthetics improve post-ischemic recovery. A meta-analysis suggested that the cardioprotective properties of desflurane and sevoflurane could reduce mortality and cardiac morbidity in cardiac surgery. Recent American College of Cardiology / American Heart Association Guidelines recommended volatile anesthetic agents during non-cardiac surgery for the maintenance of general anesthesia in patients at risk for myocardial infarction but whether these cardioprotective properties exist in non-cardiac surgery settings is controversial. We therefore performed a meta-analysis of randomized studies to investigate this issue. METHODS: Two investigators independently searched PubMed. Inclusion criteria were random allocation to treatment, comparison of a total intravenous anesthesia regimen vs an anesthesia plan including desflurane or sevoflurane, performed on adult patients undergoing non-cardiac surgery. The primary endpoints were the incidence of perioperative myocardial infarction and death. RESULTS: A total of 6219 patients from 79 randomized trials were identified. No myocardial infarctions or deaths were reported in any of the studies we examined. CONCLUSIONS: This meta-analysis highlights a weakness in the literature and the results can be used to design future studies: the cardioprotective properties of desflurane and sevoflurane have never been studied in noncardiac surgery. No randomized study, among those which compared desflurane or sevoflurane to intravenous anesthetics, has addressed major outcomes such as myocardial infarction or mortality. Large, multicentre, randomized clinical trials including patients undergoing high-risk non-cardiac surgery and reporting clinically relevant outcomes such as myocardial infarction and mortality are needed.