The effect of dexmedetomidine sedation on brachial plexus block in patients with end-stage renal disease.

BACKGROUND AND OBJECTIVE: The study investigated the effect of intravenous dexmedetomidine on brachial plexus block in patients with end-stage renal disease sedated with dexmedetomidine or midazolam for the formation of arteriovenous fistula.

METHODS: A supraclavicular brachial plexus block was performed in 68 patients scheduled for an arteriovenous fistula formation. A successful block was achieved in 64 patients (94%). Sixty-four patients received either dexmedetomidine (loading dose 1 microg kg 10 min followed by infusion of 0.2-0.7 microg kg h) or midazolam (bolus dose 0.04 mg kg followed by infusion of 0.04-0.08 mg kg h). Three patients were excluded during the study. Finally, 61 patients were analysed, 32 in the dexmedetomidine group and 29 in the midazolam group. Administration of the study drug was started after achievement of a complete block. The duration of the motor and sensory block was assessed.

RESULTS: The motor and sensory block was longer in the dexmedetomidine group (11.9 +/- 3.8 vs. 9.4 +/- 3.4 h, P = 0.0085 and 9.4 +/- 3.4 vs. 7.3 +/- 2.8 h, P = 0.030, respectively).

CONCLUSION: A systemic administration of dexmedetomidine prolongs the duration of brachial plexus block.