Hypothesis: Light general anesthesia leads to a decrease in all cause mortality at 1-year post surgery (vs. deeper anesthesia).
Methods: Eligible patients were randomized to a ‘light’ GETA group (BIS of 50+/-5, N = 3316) v a ‘deep’ GETA group (BIS 35+/-5, N = 3328), and then followed up at 1 year to assess mortality.
Results: There was no difference in all cause mortality between groups, nor were there significant differences in MI, stroke, awareness or disability-free survival.
Strengths:
Large, multicenter RCT
Patient and evaluator blinded
Diverse patient population with significant comorbidity burden
Attempted to eliminate hemodynamic confounding between groups
Relevant study question
Weaknesses:
Lack of provider blinding
Questionable/ arbitrary BIS targets (35 and 50)
Did not report on use of paralytic
Post op cognitive dysfunction not examined
Key Point: There was no difference in mortality or in any other measured secondary outcome between patients undergoing surgery with ‘light’ vs ‘deep’ levels of anesthesia.