No Survival Benefit for Volatile Anesthesia in Elective CABG Surgery

By Reuters Staff

March 20, 2019

NEW YORK (Reuters Health) - In a comparison of gas versus needle, a new pragmatic trial has shown that using a volatile anesthesia agent during elective coronary-artery bypass grafting (CABG) did not produce fewer deaths after one year.

The MYRIAD trial was stopped for futility after 2.8% of the 2,709 patients in the volatile anesthetics group died and 3.0% of the 2,691 in the total intravenous (IV) group didn't make it to the one-year mark (P=0.71).

The researchers had been hoping for a reduction in the death rate of one percentage point.

The findings were released Tuesday at the 39th International Symposium on Intensive Care and Emergency Medicine in Brussels and online by the New England Journal of Medicine.

The test had been undertaken because it was thought that the inhaled anesthetics might offer cell-protective effects. In animal models, volatile anesthetics have been known to reduce myocardial infarct size. Meta-analyses and various human studies have produced mixed conclusions on the question.

Thirty six centers in 13 countries were involved in the test, funded by the Italian Ministry of Health.

The volatile anesthetics were desflurane, isoflurane or sevoflurane, with the latter having been used in 83% of patients. Propofol was used in most (88%) of the IV group, followed midazolam.

The 30-day death rate was 1.4% with a volatile anesthetic versus 1.3% with IV treatment. The rates for a composite of death or nonfatal myocardial infarction within 30 days were 5.0% and 4.7% respectively.

Similarly, 10.1% of the patients in the volatile group were hospitalized within a year of discharge versus 9.8% of those who received IV anesthesia.

Side effect profiles were comparable. Secondary analyses showed no benefit for inhaled anesthetics either.

A comparison of patients who received on-pump and off-pump CABG also failed to show a preference based on the type of anesthesia.


N Engl J Med 2019.