Oral clonidine pre-treatment and diazepam/meperidine sedation.

Clonidine has recently been used as a pre-operative medication and sedative/anxiolytic drug. Its extended duration of action makes it suitable for longer procedures. In this randomized, crossover, placebo-controlled clinical trial, we characterized the effects of oral clonidine pre-treatment on intravenous diazepam/meperidine sedation using the bi-spectral index (BIS) in 13 participants. Clonidine significantly increased the numbers of BIS-depressed readings and percent memory loss during sedation, while reducing total diazepam and post-operative analgesic dosages by 44% and 55%, respectively. Systolic, diastolic, and mean arterial blood pressures, as well as pulse rates, were reduced. Respiratory rate, oxygen saturation, end-tidal CO(2), and recovery from sedation were unchanged. Participants, surgeons, and sedationists preferred clonidine over the placebo. Clonidine pre-treatment increased and prolonged sedation and amnesia and stabilized vital signs while significantly decreasing diazepam and post-operative analgesic usage. These results suggest that pre-operative clonidine administration could be a useful supplement to intravenous sedation for dental procedures of long duration.