Effect Of Sufentanil On Bispectral Index In The Elderly

We examined the impact of adding sufentanil during anaesthesia induction with propofol on bispectral index values in elderly patients (>= 65 years). Patients were randomly assigned to receive a target-controlled sufentanil infusion (effect-site concentration of 0.3 ng.ml(-1)) or matching placebo, followed by a target-controlled propofol induction (initial effect-site concentration of 0.5 mu g.ml(-1); step-wise increase of 0.5 mu g.ml(-1)) until loss of consciousness defined as an Observer's Assessment of Alertness/Sedation score < 2. Seventy-one patients (sufentanil 35, placebo 36) completed the study. Mean (SD) age was 72.3 (5.8) years; 41% were women. At loss of consciousness, mean (SD) bispectral index value was 75.0 (8.6) with sufentanil and 70.0 (8.0) with placebo; mean difference -5.0 (95% confidence interval -8.9 to -1.1), p = 0.013. Post-hoc analyses suggest that the difference was significant in men only (mean difference -7.3 (-11.8 to -2.6), p = 0.003). Sufentanil co-induction with propofol results in higher bispectral index values at loss of consciousness in elderly patients.