Bispectral Index in the sedation with intranasal midazolam and intravenous diazepam in dental practice.

Summary Objectives. Aim of this study was to assess by clinical evaluation and by bispectral index (BIS) the tranquillizing properties of diazepam injected intravenously, and midazolam by intranasal route according to the body weight in dental patients. Methods. A group of 34 patients undergoing implantology were divided at random in two groups of 17. They were evaluated physically, clinically and psychologically. The psychomotor activity was measured by the Newman’s test. Preoperative anxiety was treated with chlordemethyldiazepam (CHDDZ) per os, administered before induction of conscious sedation. In the first group conscious sedation was accomplished by induction with titrated doses of i.v. diazepam, and in the second group with 0.1 mg/kg of intranasal midazolam. BIS values were analysed as Area Under the Curve (AUC). Results. The AUC BIS values after CHDDZ presedation were overlapping in both groups. AUC after midazolam decreased after induction of the conscious sedation (p<0.05), during anesthesia (p<0.01) and during intervention (p<0.01) compared to the diazepam treatment. In the midazolam group the BIS values were on average lower than 90, while in the diazepam group they were on average higher then 95 (p<0.01). The psychomotor recovery was more impaired after midazolam. Discussion. The study shows that nasal route ensures the quick absorption of midazolam as revealed during the first 3 minutes from drug administration. The depressant effect of midazolam increased as a function of time, reaching the highest levels during intervention. Conclusion. The results suggest that midazolam is endowed with sedative effects which may compromise the state of consciousness of the patient and be incompatible with the definition of conscious sedation in dentistry.