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Novel analgesic adjuncts for brachial plexus block: a systematic review
D B Murphy1, C J McCartney, V W Chan
1Department of Anaesthesia and Pain Management, Toronto Western Hospital University Health Network, Toronto, Canada.
Anesthesia and Analgesia
|April 27, 2000
Summary
Clonidine shows promise as an effective analgesic adjunct for brachial plexus blocks, offering prolonged pain relief with minimal side effects. Evidence for other adjuncts like opioids, tramadol, and neostigmine is currently insufficient for recommendation.
Area of Science:
- Anesthesiology
- Pain Management
- Pharmacology
Background:
- Brachial plexus block is a regional anesthesia technique.
- Novel analgesic adjuncts are explored to enhance block efficacy and duration.
- The aim is to improve analgesia while minimizing systemic side effects and motor block.
Purpose of the Study:
- To review current evidence on the efficacy of adding novel analgesic adjuncts to brachial plexus blocks.
- To assess the potential for prolonged analgesia, reduced local anesthetic dose, and fewer side effects.
Main Methods:
- Systematic review of 24 studies meeting specific inclusion criteria.
- Assessment of studies for peripheral versus systemic effects of adjuncts.
- Inclusion of studies with systemic control groups to evaluate peripheral efficacy.
Main Results:
- Evidence for opioid adjuncts is equivocal, requiring more research.
- Clonidine (up to 150 microg) demonstrates significant analgesic benefit with minimal adverse effects.
- Insufficient data exists for recommending tramadol or neostigmine adjuncts.
Conclusions:
- Clonidine is a potentially valuable adjunct for brachial plexus blocks.
- Routine use of opioid adjuncts is not yet recommended due to insufficient evidence.
- Further research is needed for tramadol and neostigmine to establish their role.
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