title: Electrical exposure risk associated with hands-on defibrillation.
abstract: BACKGROUND
  The use of hands-on defibrillation (HOD) to reduce interruption of chest compression after cardiac arrest has been suggested as a means of improving resuscitation outcomes. The potential dangers of this strategy in regard to exposing rescuers to electrical energy are still being debated. This study seeks to determine the plausible worst-case energy-transfer scenario that rescuers might encounter while performing routine resuscitative measures.
  
  
  METHODS
  Six cadavers were acquired and prepared for defibrillation. A custom instrumentation-amplifier circuit was built to measure differential voltages at various points on the bodies. Several skin preparations were used to determine the effects of contact resistance on our voltage measurements. Resistance and exposure voltage data were acquired for a representative number of anatomic landmarks and were used to map rescuers' voltage exposure. A formula for rescuer-received dose (RRD) was derived to represent the proportion of energy the rescuer could receive from a shock delivered to a patient. We used cadaver measurements to estimate a range of RRD.
  
  
  RESULTS
  Defibrillation resulted in rescuer exposure voltages ranging from 827V to ∼200V, depending on cadaver and anatomic location. The RRD under the test scenarios ranged from 1 to 8J, which is in excess of accepted energy exposure levels.
  
  
  CONCLUSIONS
  HOD using currently available personal protective equipment and resuscitative procedures poses a risk to rescuers. The process should be considered potentially dangerous until equipment and techniques that will protect rescuers are developed.
authors.affiliation: Department of Emergency Medicine, University of Maryland School of Medicine, Baltimore, MD, United States. Electronic address: dlemkin@em.umaryland.edu.
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Lemkin
authors.affiliation: Department of Emergency Medicine, University of Maryland School of Medicine, Baltimore, MD, United States.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Witting
authors.affiliation: Department of Emergency Medicine, University of Maryland Medical Center, Baltimore, MD, United States.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Allison
authors.affiliation: Department of Emergency Medicine, University of Maryland School of Medicine, Baltimore, MD, United States.
authors.forename: Ali
authors.initials: A
authors.lastname: Farzad
authors.affiliation: Department of Emergency Medicine, University of Maryland School of Medicine, Baltimore, MD, United States.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Bond
authors.affiliation: Linear Technology, Hayward, CA, United States.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Lemkin
mesh_terms: D002102:Cadaver; D003430:Cross-Sectional Studies; D004554:Electric Countershock / Q000009:adverse effects*; D004556:Electric Injuries / Q000209:etiology*; D004634:Emergency Medical Technicians; D006801:Humans; D060051:Occupational Injuries / Q000209:etiology*; D018570:Risk Assessment
keywords: Cardiopulmonary resuscitation; Defibrillation; Rescuer