Inhaled anesthetics of no good in improving survival in CABG

DELHI: Volatile (inhaled) anesthetics, although known to have a cardioprotective role but did not improve survival in patients undergoing coronary artery bypass grafting (CABG) compared to the use of total intravenous anesthesia, finds a recent study.

The study, published in the New England Journal of Medicine, was conducted by Giovanni Landoni, of Vita-Salute San Raffaele University, Italy, and colleagues. They wanted to see if the use of volatile anesthetics as part of a patient’s anesthesia lead to better outcomes in patients who undergo the procedure.

For the purpose, the researchers conducted a pragmatic, multicenter, single-blind, controlled trial at 36 centers in 13 countries. A total of 5400 patients scheduled to undergo CABG, were randomly assigned -- 2709 to the volatile anesthetics group and 2691 to the total intravenous anesthesia group. About two-thirds (64%) of the patients in the study underwent on-pump CABG procedures, and mean length of time of cardiopulmonary bypass was 79 minutes. The primary outcome was death of any cause at 1 year.

Key findings of the study include:

• No significant difference between the groups with respect to deaths from any cause was seen at 1 year (2.8% in the volatile anesthetics group and 3.0% in the total intravenous anesthesia group), with data available for 5353 patients (99.1%), or at 30 days, with data available for 5398 patients (99.9%).


• There were no significant differences between the groups in any of the secondary outcomes or in the incidence of prespecified adverse events, including myocardial infarction.


• The odds of death at 30 days were similar between the 2 groups, as were the adverse event profiles.

In finding no benefit to volatile anesthetics, Landoni and colleagues differed from other studies. One difference between this study and earlier research was the inclusion of off-pump CABG patients in the data. However, Landoni and colleagues wrote that a pre-specified subgroup analysis found there was no variance in outcomes in the primary outcome in on-pump versus off-pump procedures.

Another factor that might have affected the outcome is the coadministration of propofol during induction of anesthesia. There has been conflicting evidence about what effect propofol might have on patient outcomes and on the cardioprotective benefits of volatile anesthetics. Landoni said that question is worthy of further study.

"Among patients undergoing elective CABG, anesthesia with a volatile agent did not result in significantly fewer deaths at 1 year than total intravenous anesthesia," concluded the authors.

For detailed study log on to 10.1056/NEJMoa1816476