title: Pathophysiology and Etiology of Nerve Injury Following Peripheral Nerve Blockade.
abstract: This review synthesizes anatomical, anesthetic, surgical, and patient factors that may contribute to neurologic complications associated with peripheral nerve blockade. Peripheral nerves have anatomical features unique to a given location that may influence risk of injury. Peripheral nerve blockade-related peripheral nerve injury (PNI) is most severe with intrafascicular injection. Surgery and its associated requirements such as positioning and tourniquet have specific risks. Patients with preexisting neuropathy may be at an increased risk of postoperative neurologic dysfunction. Distinguishing potential causes of PNI require clinical assessment and investigation; a definitive diagnosis, however, is not always possible. Fortunately, most postoperative neurologic dysfunction appears to resolve with time, and the incidence of serious long-term nerve injury directly attributable to peripheral nerve blockade is relatively uncommon. Nonetheless, despite the use of ultrasound guidance, the risk of block-related PNI remains unchanged.
  Since the 2008 Practice Advisory, new information has been published, furthering our understanding of the microanatomy of peripheral nerves, mechanisms of peripheral nerve injection injury, toxicity of local anesthetics, the etiology of and monitoring methods, and technologies that may decrease the risk of nerve block-related peripheral nerve injury.
authors.affiliation: From the *Departments of Anesthesia, Toronto Western Hospital, University Health Network, and Women's College Hospital, University of Toronto, Toronto, Ontario, Canada; †Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, St Luke's and Roosevelt Hospitals, New York, NY; ‡School of Medicine, CEU San Pablo University, and Madrid Montepríncipe University Hospital, Madrid, Spain; and §Department of Anaesthesia, St Vincent's Hospital; Melbourne Medical School, The University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Richard
authors.initials: R
authors.lastname: Brull
authors.forename: Admir
authors.initials: A
authors.lastname: Hadzic
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Reina
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Barrington
mesh_terms: D001340:Autonomic Nerve Block / Q000009:adverse effects* / Q000639:trends; D006801:Humans; D059348:Peripheral Nerve Injuries / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D010525:Peripheral Nerves / Q000187:drug effects / Q000502:physiology; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology