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Published on: September 8, 2011
Local Anesthetic-Induced Myotoxicity After Continuous Adductor Canal Block.
Joseph M Neal1, Francis V Salinas, Daniel S Choi
1From the *Department of Anesthesiology, Virginia Mason Medical Center; †Department of Anesthesiology, Physicians Anesthesia Service, Seattle, WA; and ‡Department of Anesthesiology, Kaiser Permanente Orange County, Southern California Permanente Medical Group, Irvine, CA.
Local anesthetic-induced myotoxicity is rare in humans but occurred in three patients after continuous adductor canal block (ACB). Symptoms included profound quadriceps weakness, with partial to full recovery over weeks to months.
Area of Science:
- Anesthesiology
- Neuromuscular Medicine
Background:
- Local anesthetic-induced myotoxicity is well-documented in animal models.
- Clinically significant myotoxicity is rarely reported in humans, particularly following non-ophthalmic surgical procedures.
Observation:
- Three patients developed progressive, profound quadriceps muscle weakness on postoperative days 1 or 2 after total knee arthroplasty.
- The anesthetic regimen included a subarachnoid block combined with a continuous adductor canal block (ACB) using lidocaine or mepivacaine followed by ropivacaine.
Findings:
- Clinical presentation, imaging, and neurophysiologic studies were consistent with myositis.
- The observed myotoxicity was linked to the continuous adductor canal block procedure.
Implications:
- These cases highlight the potential for local anesthetic-induced myotoxicity in humans, even with continuous regional anesthesia techniques like ACB.
- Awareness of this adverse event is crucial for prompt diagnosis and management in patients undergoing similar procedures.
- Further investigation may be warranted to elucidate the precise mechanisms and risk factors for ACB-associated myotoxicity.
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