[Intravenous dexmedetomidine for sedation does not interfere with sensory and motor block duration during spinal...

The association among local and regional anesthesia is a very useful and common practice. However, some patients may become anxious and require sedation. Benzodiazepines, opioids and propofol are widely used for this aim. Alpha2-adrenergic agonists have hypnotic and sedative properties and represent an alternative to promote hemodynamic stability and minor respiratory depression. This study aimed at evaluating the safety and the interference of intravenous dexmedetomidine or midazolam on sensory and motor block duration spinal anesthesia.

Thirty five adult female patients, physical status ASA I and II, were submitted to spinal anesthesia with hyperbaric 0.5% bupivacaine (15 mg) for elective gynecologic surgery. The patients were randomized and distributed in two groups: Group M (n = 17) - sedation with 0.25 microg.kg-1.min-1 midazolam continuous infusion and Group D (n = 18) sedation with 0.5 microg.kg-1.min-1 dexmedetomidine continuous infusion. Infusion rate was adjusted to maintain BIS between 60 and 80. The following parameters were evaluated: SBP, DBP, HR, SpO2, BIS sensory and motor block extension and duration (Bromage scale).

There were no statistically significant differences between groups in age, weight, sensory block level, blood pressure and heart rate variation and sensory and motor block duration.

Intravenous dexmedetomidine for sedation has not interfered with hemodynamic parameters, spinal anesthesia sensory and motor block duration or extension and it is a good option for sedation during local/regional anesthesia.