The effect of dexmedetomidine as an adjuvant to ropivacaine on the bispectral index for supraclavicular brachial plexus block

Abstract

BackgroundThe aim of this study was to evaluate the sedative effect of dexmedetomidine (DEX) added to ropivacaine for supraclavicular brachial plexus block (BPB) using the bispectral index (BIS).MethodsSixty patients (American Society of Anesthesiologists physical status 1 or 2, aged 20-65 years) undergoing wrist and hand surgery under supraclavicular BPB were randomly allocated to two groups. Ultrasound-guided supraclavicular BPB was performed with 40 ml of ropivacaine 0.5% and 1 µg/kg of DEX (Group RD) or 0.01 ml/kg of normal saline (Group R). The primary endpoint was the BIS change during 60 min after block. The secondary endpoint was the change in the mean arterial blood pressure (MAP), heart rate (HR), and SpO2 and the onset time and duration of the sensory and motor block.ResultsIn Group RD, the BIS decreased significantly until 30 min after the block (69.2 ± 13.7), but remained relatively constant to 60 min (63.8 ± 15.3). The MAP, HR and BIS were significantly decreased compared with Group R. The onset time of the sensory and motor block were significantly faster in Group RD than in Group R. The duration of the sensory and motor block were significantly increased in Group RD.ConclusionsDEX added to ropivacaine for brachial plexus block induced sedation that corresponds to a BIS value of 60 from which patients are easily awakened in a lucid state. In addition, perineural DEX shortened the onset time and prolonged the duration of the sensory and motor blocks.

Investigating the Efficacy of Dexmedetomidine as an Adjuvant to Local Anesthesia in Brachial Plexus Block

“…In regard to the type of brachial plexus block used, a total of 10 studies utilized a supraclavicular block, 4,15,18,19,[22][23][24][25]27,30 3 used an axillary block, 20,26,29 3 used an interscalene block, 14,17,21 and 2 used an infraclavicular block. 16,28 Dexmedetomidine was used as an adjuvant to several different local anesthetics, which included levobupivacaine, 17,18,20,25,28 ropivacaine, 14,19,21,23,24,27,29,30 bupivacaine, 4,15,16,22 and mepivacaine. 28 Across the studies, the dose of dexmedetomidine ranged from 0.5 μg/kg to a total of 150 μg.…”

“…Studies were grouped according to dosage of dexmedetomidine. Doses greater than 50 μg 4,14,16,19,20,[25][26][27] led to a significant reduction in sensory block onset time (MD, −2.61 minutes; 95% CI, −3.93 to −1.30 minutes; I 2 = 94%; P < 0.0001); however, no significance was observed at doses 50 μg or less 17,[22][23][24]29 (MD, −5.07 minutes; 95% CI, −11.93 to 1.78 minutes; I 2 = 96%; P = 0.15). The data were also stratified according to location of the overall block.…”

“…The data were also stratified according to location of the overall block. Dexmedetomidine, when given as an adjuvant for supraclavicular 4,15,19,[22][23][24][25]27 (MD, −3.20 minutes; 95% CI, −5.13 to −1.27 minutes; I 2 = 96%; P =0.001), infraclavicular 16 (MD, −6.20 minutes; 95% CI, −7.45 to −4.95 minutes; I 2 = N/A; …”

“…The addition of dexmedetomidine significantly prolonged duration of sensory blockade irrespective of the dosage (≤50 μg [22][23][24]29 or >50 μg 4,15,16,18-20,25-28 ), location of block (eg, supraclavicular, 4,15,18,19,[22][23][24][25]27 infraclavicular, 16,28 or axillary 20,26,29 ), or the local anesthetic given (eg, ropivacaine, 19,23,24,27,29 bupivacaine, 4,15,16,22 levobupivacaine, 18,20,25,26 or mepivacaine 28 ).…”

Physiological Responses and Gene Expression in Ultrasound-Guided Supraclavicular Brachial Plexus Block: a Comparative Study

“…Several adjuvants have been co-administered with bupivacaine, but the results have been either unconvincing or associated with untoward complications [4]. Several researchers have attempted to combine bupivacaine with other anesthetics such as ketamine [5], clonidine [6], midazolam [1], and neostigmine [7] with various success rates.…”