Complications of Regional Anesthesia: Upper and Lower Extremity Blockade

  • Stephen Choi
  • Patrick B. Y. Wong
  • Kristen Gadbois
  • Colin J. L. McCartney
Chapter

Key Points

  • Nerve injury after peripheral nerve blocks can be due to needle trauma, chemical neurotoxicity, ischemia, or compression.

  • Intraneural needle placement can cause significant injury, either from direct needle trauma or pressure-related ischemia after injection. Although this probably occurred without sequelae prior to the advent of ultrasound-guided regional anesthesia, there is no evidence to support deliberate intraneural injection. On the contrary, current guidelines recommend utmost care should be taken to avoid accidental intraneural needle placement.

  • The hypothesis that performing peripheral nerve blocks under ultrasound guidance can prevent direct needle injury has not been proven. However, there is evidence to suggest that ultrasound use may decrease the incidence of local anesthetic systemic toxicity (LAST ) for peripheral nerve blocks.

  • Local anesthetics have been shown to have neurotoxic effects during in vitro studies. Although the dose and concentration used in clinical practice is generally safe, it is prudent to use the lowest concentration possible to achieve the desired effect.

  • After peripheral nerve block temporary neurologic deficits may occur in 3 % of patients with most symptoms resolving within days or weeks of surgery. Permanent injury is rare, occurring on average 2.4 instances per 10,000 blocks.

  • Practitioners must be familiar with the potential complications specific to each nerve block prior to performance.

Keywords

Intraneural Needle trauma Chemical neurotoxicity Compression Neurologic deficits 

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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Stephen Choi
    • 1
  • Patrick B. Y. Wong
    • 2
  • Kristen Gadbois
    • 2
  • Colin J. L. McCartney
    • 2
  1. 1.Department of AnesthesiaSunnybrook Health Sciences Centre, University of TorontoTorontoCanada
  2. 2.Department of Anesthesiology and Pain MedicineUniversity of OttawaOttawaCanada

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