title: Intraneural injections and regional anesthesia: the known and the unknown.
abstract: Peripheral nerve injury is a rare complication of regional anesthesia. Intraneural injections were once considered harbingers of neural injury with practitioners focusing on their avoidance. With ultrasound guidance, it is now possible to visualize the difference between perineural (outside the nerve), intraneural (below the epineurium), and intrafascicular (within the perineurium) injections and to determine their association with postoperative neurological complications. We also now have a better understanding of the multifactorial nature of neurologic injury based on the nerve anatomy, site of needle insertion, bevel type, location of the needle tip, pressure achieved during injection, and underlying patient factors. Using ultrasound guidance during nerve blocks has revealed that not all intraneural injections result in injury, and its use will continue to provide insight into the mechanism of anesthetic-related nerve injury.
authors.affiliation: Department of Anesthesiology, Mount Sinai School of Medicine, New York, NY 10029-6579, USA.
authors.forename: C L
authors.initials: CL
authors.lastname: Jeng
authors.forename: M A
authors.initials: MA
authors.lastname: Rosenblatt
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage / Q000009:adverse effects*; D000818:Animals; D020516:Brachial Plexus Neuropathies / Q000209:etiology; D004285:Dogs; D004558:Electric Stimulation; D004867:Equipment Design; D006801:Humans; D009339:Needles; D016602:Needlestick Injuries / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D009407:Nerve Block / Q000009:adverse effects* / Q000295:instrumentation; D059348:Peripheral Nerve Injuries; D010525:Peripheral Nerves / Q000000981:diagnostic imaging / Q000187:drug effects / Q000648:ultrastructure; D011183:Postoperative Complications / Q000209:etiology / Q000517:prevention & control; D011817:Rabbits; D051381:Rats; D012584:Sciatic Nerve / Q000293:injuries; D014463:Ultrasonography
chemical_list: D000779:Anesthetics, Local