Volatile Anesthetics Versus Total Intravenous Anesthesia in Patients Undergoing Coronary Artery Bypass Grafting: An Updated Meta-analysis and Trial Sequential Analysis of Randomized Controlled Trials

Background: The benefits of volatile anesthetics in coronary artery bypass grafting (CABG) patients remain controversial. We aimed to conduct an updated meta-analysis to assess whether the use of volatile anesthetics during CABG could reduce mortality and other outcomes.

Methods: We searched eight databases from inception to June 2019 and included randomized controlled trials (RCTs) comparing the effects of volatile anesthetics versus total intravenous anesthesia (TIVA) in CABG patients. The primary outcomes were operative mortality and one-year mortality. The secondary outcomes included the length of stay in the intensive care unit (ICU) and hospital and postoperative safety outcomes (myocardial infarction, heart failure, arrhythmia, stroke, delirium, postoperative cognitive impairment, acute kidney injury, and the use of intra-aortic balloon pump (IABP) or other mechanical circulatory support). Trial sequential analysis (TSA) was performed to control for random errors.

Results: A total of 89 RCTs comprising 14,387 patients were included. There were no significant differences between the volatile anesthetics and TIVA groups in operative mortality (relative risk (RR) = 0.92, 95% confidence interval (CI): 0.68-1.24, p = 0.59, I2 = 0%), one-year mortality (RR = 0.64, 95% CI: 0.32-1.26, p = 0.19, I2 = 51%), or any of the postoperative safety outcomes. The lengths of stay in the ICU and hospital were shorter in the volatile anesthetics group than in the TIVA group. TSA revealed that the results for operative mortality, one-year mortality, length of stay in the ICU, heart failure, stroke, and the use of IABP were inconclusive.

Conclusions: Conventional meta-analysis suggests that the use of volatile anesthetics during CABG is not associated with reduced risk of mortality or other postoperative safety outcomes when compared with TIVA. TSA shows that the current evidence is insufficient and inconclusive. Thus, future large RCTs are required to clarify this issue.