title: Asphyxiation due to dry ice in a walk-in freezer.
abstract: BACKGROUND
  Exposure to a high concentration of environmental carbon dioxide (CO2) can result in poisoning through direct toxicity and by displacing atmospheric oxygen (O2). Dry ice undergoes sublimation to a gaseous state at -78.5 degrees C (-109.3 degrees F), which is heavier than air and can accumulate in dependent areas.
  
  
  METHODS
  We report the case of a 59-year-old man found in cardiac arrest shortly after entering a recently repaired walk-in freezer that contained dry ice. First responders and bystanders did not recognize the proximate hazardous environment but were fortunately uninjured. A careful Emergency Department history coupled with rapid case investigation by the Medical Examiner's Office led to the determination of the cause of death and the elimination of the ongoing hazard.
  
  
  CONCLUSIONS
  This case illustrates the lethal consequences of improper storage of dry ice and the need to consider toxic environmental exposure as a cause of sudden cardiac arrest.
authors.affiliation: Department of Emergency Medicine, University of California, San Diego Medical Center, San Diego, California 92103-8676, USA.
authors.forename: James V
authors.initials: JV
authors.lastname: Dunford
authors.forename: Jon
authors.initials: J
authors.lastname: Lucas
authors.forename: Nick
authors.initials: N
authors.lastname: Vent
authors.forename: Richard F
authors.initials: RF
authors.lastname: Clark
authors.forename: F Lee
authors.initials: FL
authors.lastname: Cantrell
mesh_terms: D001237:Asphyxia / Q000209:etiology*; D004367:Dry Ice / Q000009:adverse effects*; D017809:Fatal Outcome; D005615:Freezing; D006801:Humans; D008297:Male; D008875:Middle Aged; D016272:Occupational Health; D017132:Workplace / Q000523:psychology*
chemical_list: D004367:Dry Ice