Ultrasound-guided single injection infraclavicular brachial plexus block using bupivacaine alone or combined with dexmedetomidine for pain control in upper limb surgery: A prospective randomized controlled trial

Abstract

Background:Dexmedetomidine, is a selective α2-adrenoceptor agonist that is used as an adjuvant mixed with local anesthetics during regional anesthesia. This study was designed to test the efficacy of adding dexmedetomidine to bupivacaine during placement of infraclavicular brachial plexus blockade (ICB).Methods:Sixty adult patients were divided into 2 equal groups of 30 subjects each. Patients in Group I received an ICB using 30 mL of 0.33% bupivacaine and Group II patients received 30 mL of 0.33% bupivacaine mixed with 0.75 μg/kg of dexmedetomidine. The following brachial plexus nerve block parameters were assessed: block success rate, sensory onset time and duration, motor block onset time and duration, analgesic pain scores using the verbal rating scale (VRS) for pain, duration of analgesia, and amount of supplemental intravenous (IV) morphine required.Results:There was a statistically significant shorter time to onset of sensory blockade (13.2 vs 19.4 min, P=0.003), longer duration of sensory block (179.4 vs 122.7 min, P=0.002), shorter onset time to achieve motor block (15.3 vs 22.2 min, P=0.003), longer duration of motor block (155.5 vs 105.7 min, P=0.002), lower VRS pain scores, prolonged analgesia (403 vs 233 min, P=0.002), and lower morphine rescue requirements for 48 h after surgery (4.9 (0–8.0) vs 13.6 mg (4.0–16.0) mg, P=0.005). All patients recovered without evidence of sensory or motor deficit.Conclusion:Adding dexmedetomidine to bupivacaine during the placement of an ICB provides: (1) enhancement of onset of sensory and motor blockade, (2) prolonged duration of analgesia, (3) increases duration of sensory and motor block, (4) yields lower VRS pain scores, and (5) reduces supplemental opioid requirements.

Effect of dexmedetomidine as adjuvant in ropivacaine-induced supraclavicular brachial plexus block: A prospective, double-blinded and randomized controlled study

“…Dexmedetomidine is highly selective (8 time more selective than clonidine),[ 7 ] specific and potent α 2 -adrenergic agonist having analgesic, sedative, antihypertensive, and anesthetic sparing effects when used in systemic route. [ 8 ] Adding dexmedetomidine to local anesthetics during peripheral nerve blockade[ 9 ] and regional anesthesia[ 10 ] procedures may also prove efficacious for the surgical patients. In human study, dexmedetomidine has also shown to prolong the duration of the block and post-operative analgesia when added to local anesthetic in various regional blocks.…”

Supraclavicular brachial plexus block: Comparison of varying doses of dexmedetomidine combined with levobupivacaine: A double-blind randomised trial

“…[15] Similarly, Ammar and Mahmoud also found that significantly lower IV morphine (4.9 mg vs. 13.6 mg) was given as rescue analgesic in the bupivacaine plus dexmedetomidine group while comparing with plain bupivacaine group in infraclavicular brachial plexus block. [16]…”

A comparative clinical study of perineural administration of 0.75% ropivacaine with and without dexmedetomidinein upper limb surgery by ultrasound guided single injection supraclavicular brachial plexus block

“…However they did not found any consistently significant differences in blood pressures between the groups [24]. Amany S. Ammar et al in their clinical trial added dexmedetomidine to bupivacaine during placement of ultrasound guided infraclavicular block and they concluded that adding dexmedetomidine to bupivacaine enhanced onset and duration of sensory and motor block, prolonged duration of analgesia and yields lower VAS pain scores [25].…”