Aim: Bispectral Index Score (BIS) is an objective tool to assess sedation depth. Benzodiazepines have different pharmacological profiles and diazepam may be safer than midazolam in this setting. The aim of this study was to compare BIS values observed during anxiolysis after diazepam versus sedation after midazolam.
Methods: Thirty-six patients were randomly assigned to 3 groups: group 1 was treated with i.v. diazepam, groups 2 and 3 with iv midazolam 1 and 3 mg, respectively. Sedation was monitored clinically and by means of BIS. BIS values were evaluated as area under the curve (AUC) and compared by variance analysis. The statistical comparison of other data was performed by variance analysis or, alternatively, the χ2 according to Yates. The statistical significance was indicated by P values <0.05.
Results: AUC values were significantly lower after midazolam when compared to AUC values registered in diazepam treated patients; 22.6% of the group 3 patients showed BIS values <80, versus 0.4% of group 1 patients.
Conclusion: Diazepam has a safer profile, with BIS values and clinical conditions according to the definition of minimal and/or moderate sedation. Diazepam represents the safer drug for anxiety management in dentistry, because regularly produces a state of sedation during which verbal contact with the patient is maintained and carry a margin of safety wide enough to render loss of consciousness unlikely.