title: Prophylactic lidocaine for post resuscitation care of patients with out-of-hospital ventricular fibrillation cardiac arrest.
abstract: BACKGROUND
  Antiarrhythmic drugs like lidocaine are usually given to promote return of spontaneous circulation (ROSC) during ongoing out-of-hospital cardiac arrest (OHCA) from ventricular fibrillation/tachycardia (VF/VT). Whether administering such drugs prophylactically for post-resuscitation care after ROSC prevents re-arrest and improves outcome is unstudied.
  
  
  METHODS
  We evaluated a cohort of 1721 patients with witnessed VF/VT OHCA who did (1296) or did not receive prophylactic lidocaine (425) at first ROSC. Study endpoints included re-arrest, hospital admission and survival.
  
  
  RESULTS
  Prophylacic lidocaine recipients and non-recipients were comparable, except for shorter time to first ROSC and higher systolic blood pressure at ROSC in those receiving lidocaine. After initial ROSC, arrest from VF/VT recurred in 16.7% and from non-shockable arrhythmias in 3.2% of prophylactic lidocaine recipients, 93.5% of whom were admitted to hospital and 62.4% discharged alive, as compared with 37.4%, 7.8%, 84.9% and 44.5%, of corresponding non-recipients (all p<0.0001). Adjusted for pertinent covariates, prophylactic lidocaine was independently associated with reduced odds of re-arrest from VF/VT, odds ratio, (95% confidence interval) 0.34 (0.26-0.44) and from nonshockable arrhythmias (0.47 (0.29-0.78)); a higher hospital admission rate (1.88, (1.28-2.76)) and improved survival to discharge (1.49 (1.15-1.95)). However in a propensity score-matched sensitivity analysis, lidocaine's only beneficial association with outcome was in a lower incidence of recurrent VF/VT arrest.
  
  
  CONCLUSIONS
  Administration of prophylactic lidocaine upon ROSC after OHCA was consistently associated with less recurrent VF/VT arrest, and therapeutic equipoise for other measures. The prospect of a promising association between lidocaine prophylaxis and outcome, without evidence of harm, warrants further investigation.
authors.affiliation: Department of Medicine, Division of Cardiology, University of Washington, Seattle, WA, United States; Public Health-Seattle and King County, Emergency Medical Services Division, United States. Electronic address: kudenchu@u.washington.edu.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Kudenchuk
authors.forename: Cameron
authors.initials: C
authors.lastname: Newell
authors.forename: Lindsay
authors.initials: L
authors.lastname: White
authors.forename: Carol
authors.initials: C
authors.lastname: Fahrenbruch
authors.forename: Tom
authors.initials: T
authors.lastname: Rea
authors.forename: Mickey
authors.initials: M
authors.lastname: Eisenberg
mesh_terms: D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D004632:Emergency Medical Services; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000627:therapeutic use*; D008297:Male; D058687:Out-of-Hospital Cardiac Arrest / Q000188:drug therapy* / Q000503:physiopathology; D010343:Patient Admission / Q000706:statistics & numerical data; D012042:Registries; D012189:Retrospective Studies; D055502:Secondary Prevention; D015996:Survival Rate; D014693:Ventricular Fibrillation / Q000188:drug therapy* / Q000503:physiopathology / Q000517:prevention & control
chemical_list: D000889:Anti-Arrhythmia Agents; D008012:Lidocaine
keywords: Arrhythmia; Cardiac arrest; Lidocaine