title: Local anesthetic systemic toxicity: update on mechanisms and treatment.
abstract: OBJECTIVE
  With increases in use of regional anesthesia, local anesthetic systemic toxicity (LAST) has been a topic of interest and debate. Despite many years of research, the exact cause and best treatment of LAST (particularly local anesthetic cardiotoxicity) remain unclear. This review will summarize what is known and what remains uncertain about LAST and its treatment, including information published in the past 12-18 months.
  
  
  RESULTS
  Several authorities, including the American Society of Regional Anesthesia and Pain Medicine, have published guidelines on prevention and treatment of LAST. Experimental data continue to add to better understanding of LAST and its treatment. The data are not entirely consistent, but themes include continued evidence to support the ideas that LAST cardiotoxicity occurs primarily at sodium channels, lipid emulsion is a reasonably well tolerated and effective treatment, and there may be qualitative differences in cardiotoxicity caused by low and high-potency local anesthetics.
  
  
  CONCLUSIONS
  Regarding mechanism(s) of LAST, the evidence remains mixed, but it is likely that local anesthetic cardiotoxicity primarily arises from a blockade of sodium channels. As for treatment, in addition to ventilation, oxygenation, and chest compressions, lipid emulsion therapy should be a primary element in the treatment of cardiovascular LAST. The use of epinephrine and vasopressin should be tailored to specifics of an episode of LAST, and doses should be kept as low as possible while still achieving the desired effects.
authors.affiliation: Department of Anesthesiology, Indiana University School of Medicine, Indianapolis, Indiana, USA. jwolfe@iupui.edu
authors.forename: John W
authors.initials: JW
authors.lastname: Wolfe
authors.forename: John F
authors.initials: JF
authors.lastname: Butterworth
mesh_terms: D000772:Anesthesia, Local / Q000009:adverse effects*; D000779:Anesthetics, Local / Q000009:adverse effects* / Q000633:toxicity; D000818:Animals; D002045:Bupivacaine / Q000009:adverse effects; D002318:Cardiovascular Diseases / Q000139:chemically induced / Q000188:drug therapy / Q000628:therapy; D004195:Disease Models, Animal; D004837:Epinephrine / Q000627:therapeutic use; D005217:Fat Emulsions, Intravenous / Q000627:therapeutic use; D006801:Humans; D008012:Lidocaine / Q000009:adverse effects; D020258:Neurotoxicity Syndromes / Q000188:drug therapy / Q000628:therapy; D014662:Vasoconstrictor Agents / Q000627:therapeutic use; D014667:Vasopressins / Q000627:therapeutic use
chemical_list: D000779:Anesthetics, Local; D005217:Fat Emulsions, Intravenous; D014662:Vasoconstrictor Agents; D014667:Vasopressins; D008012:Lidocaine; D002045:Bupivacaine; D004837:Epinephrine