title: Out-of-hospital cardiac arrest in denver, colorado: epidemiology and outcomes.
abstract: OBJECTIVE
  The annual incidence of out-of-hospital cardiac arrest (OOHCA) in the United States is approximately 6 per 10,000 population and survival remains low. Relatively little is known about the performance characteristics of a two-tiered emergency medical services (EMS) system split between fire-based basic life support (BLS) dispersed from fixed locations and hospital-based advanced life support (ALS) dispersed from nonfixed locations. The objectives of this study were to describe the incidence of OOHCA in Denver, Colorado, and to define the prevalence of survival with good neurologic function in the context of this particular EMS system.
  
  
  METHODS
  This was a retrospective cohort study using standardized abstraction methodology. A two-tiered hospital-based EMS system for the County of Denver and 10 receiving hospitals were studied. Consecutive adult patients who experienced nontraumatic OOHCA from January 1, 2003, through December 31, 2004, were enrolled. Demographic, prehospital arrest characteristics, treatment data, and survival data using the Utstein template were collected. Good neurologic survival was defined by a Cerebral Performance Categories (CPC) score of 1 or 2.
  
  
  RESULTS
  During the study period, 1,985 arrests occurred. Of these, 715 (36%) had attempted resuscitation by paramedics and constitute our study sample. The median age was 65 years (interquartile range = 52-78 years), 69% were male, 41% had witnessed arrest, 25% had bystander cardiopulmonary resuscitation (CPR) performed, and 30% had ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) as their initial rhythm. Of the 715 patients, 545 (76%) were transported to a hospital, 223 (31%) had return of spontaneous circulation (ROSC), 175 (25%) survived to hospital admission, 58 (8%) survived to hospital discharge, and 42 (6%, 95% confidence interval [CI] = 4% to 8%) had a good neurologic outcome.
  
  
  CONCLUSIONS
  Out-of-hospital cardiac arrest survival in Denver, Colorado, is similar to that of other United States communities. This finding provides the basis for future epidemiologic and health services research in the out-of-hospital and ED settings in our community.
authors.affiliation: Department of Emergency Medicine, Denver Health Medical Center, Denver, CO, USA. jason.haukoos@dhha.org
authors.forename: Jason S
authors.initials: JS
authors.lastname: Haukoos
authors.forename: Gary
authors.initials: G
authors.lastname: Witt
authors.forename: Craig
authors.initials: C
authors.lastname: Gravitz
authors.forename: Julianne
authors.initials: J
authors.lastname: Dean
authors.forename: David M
authors.initials: DM
authors.lastname: Jackson
authors.forename: Thomas
authors.initials: T
authors.lastname: Candlin
authors.forename: Peter
authors.initials: P
authors.lastname: Vellman
authors.forename: John
authors.initials: J
authors.lastname: Riccio
authors.forename: Kennon
authors.initials: K
authors.lastname: Heard
authors.forename: Tom
authors.initials: T
authors.lastname: Kazutomi
authors.forename: Dylan
authors.initials: D
authors.lastname: Luyten
authors.forename: Gilbert
authors.initials: G
authors.lastname: Pineda
authors.forename: Jeff
authors.initials: J
authors.lastname: Gunter
authors.forename: Jennifer
authors.initials: J
authors.lastname: Biltoft
authors.forename: Christopher
authors.initials: C
authors.lastname: Colwell
mesh_terms: D017677:Age Distribution; D000368:Aged; D016887:Cardiopulmonary Resuscitation / Q000379:methods; D002423:Cause of Death; D015331:Cohort Studies; D003120:Colorado / Q000453:epidemiology; D016001:Confidence Intervals; D004632:Emergency Medical Services / Q000379:methods / Q000592:standards*; D005260:Female; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination; D016017:Odds Ratio; D010351:Patient Discharge / Q000706:statistics & numerical data; D011336:Probability; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D017678:Sex Distribution; D016019:Survival Analysis; D014505:Urban Population