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Liposphere local anesthetic timed-release for perineural site application
1Department of Anesthesiology, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA. Masters.David@Mayo.Edu
Pharmaceutical Research
|August 4, 1998
Summary
Lipospheres effectively deliver local anesthetics for sustained peripheral nerve blocks in vivo. This drug delivery system shows dose-dependent effects and potential for neural tissue pharmacotherapy.
Area of Science:
- Biomaterials Science
- Pharmacology
- Neuroscience
Background:
- Lipospheres are triglyceride-based vesicles with phospholipid coatings.
- These vesicles are designed for controlled drug delivery applications.
Purpose of the Study:
- To evaluate Lipospheres for in vitro local anesthetic release.
- To determine the efficacy of Lipospheres in producing sustained peripheral nerve block in vivo.
Main Methods:
- Bupivacaine was loaded into Lipospheres and characterized for in vitro release.
- Lipospheres were administered around the sciatic nerve in rats to assess sensory and motor block.
Main Results:
- Lipospheres released bupivacaine over two days with particle sizes between 5-15 microm.
- Dose-dependent, reversible peripheral nerve block was achieved in vivo, lasting 1-3 days.
- Sensory blockade duration equaled or exceeded motor blockade across all tested Liposphere dosages.
Conclusions:
- Liposphere technology shows promise for site-specific pharmacotherapy of neural tissue.
- The sustained local anesthetic block (SLAB) achieved suggests potential for long-term pain management.
- Dose-dependent effects indicate lipophilic tissue storage may influence drug action duration.
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