Unmasking Local Anesthetic Injection Injury in the Peripheral Nerve

• DOI: 10.1097/01.prs.0000421769.24556.1f
• Publication Date: 2013-01-02T17:40:12Z
• Authors: Scott J. Farber; Maryam Saheb-Al-Z...; Ying Yan; Dan Hunter; Philip Johnson; Susan Mackinnon
• Keywords: Ropivacaine; Nerve Injury

INTRODUCTION: Local anesthetics (LA) are frequently used for many operative procedures. A well-known complication of LA blocks is peripheral nerve injury, whether from the needle or toxicity medication used. The purpose this study was to illustrate extent damage that results inadvertent intrafascicular injection various commonly local anesthetics. METHODS: 16 Lewis rats received an saline (control) one three LAs (bupivacaine, lidocaine, ropivacaine) into sciatic (n=4). At a 2 week endpoint, nerves were harvested histomorphometric and electron microscopic analysis. RESULTS: Animals injected with showed increased severity injury as compared control. In particular, there significant loss large diameter fibers indicated by decreased counts (p<0.001 all LAs) area remaining in severely-injured versus non-injured areas nerve. There layering most severely injured closest to, furthest site (Figure 1). No difference found between different LAs. groups, fascicular transection observed. Electron microscopy confirmed injury.Figure 1: Nerve area: relative (μm2) measured using binary imaging technique. Layering severe occurring (indicated black arrow) seen adjacent diagram.CONCLUSION: Frequently at traditional concentrations toxic can injure evidenced our data. nature vary 1st 6th degree study. Any combination long-term motor and/or sensory sequelae may result due varying topography Surgical repair be necessary, depending on resulting deficit.