PUBLIC LOCATIONS OF CARDIAC-ARREST - IMPLICATIONS FOR PUBLIC-ACCESS DEFIBRILLATION

Background-The purpose of this study was to describe the public locati ons of cardiac arrest and to estimate the annual incidence of cardiac arrest per site to determine optimal placement of automatic external d efibrillators (AEDs), This was a retrospective cohort study. Methods a nd Results-Locations of cardiac arrest were abstracted from data colle cted by emergency medical service programs in Seattle and King County, Washington, from January 1, 1990, through December 31, 1994. Types of commercial and civic establishments were tallied and grouped into 23 location categories consistent with Standard Industrial Codes, and the number of sites within each location category was determined. With th e addition of ''public outdoors'' and ''automobiles'' as categories, t here were 25 location categories. During the study period, 7185 arrest s occurred, 1130 (16%) of which were in public locations. An annual in cidence of cardiac arrest per site was calculated. Ten location catego ries with 172 sites were identified as having a higher incidence of ca rdiac arrest (greater than or equal to.03 per year per site). Thirteen location categories had a lower incidence of arrest (less than or equ al to.01 per year per site). There were approximate to 71 000 sites wi thin these categories. Conclusions-Placement of 276 AEDs in the 172 hi gher-incidence sites would have provided treatment for 134 cardiac arr est patients in a 5-year period, 60% of whom were in ventricular fibri llation. We estimate between 8 and 32 lives could be saved in 5 years. To cover the remaining 347 arrests occurring in public in a fi-year p eriod, defibrillators would have to be placed in 71 000 sites, not inc luding outdoors and automobiles. Placement of AEDs in public locations can be guided by the site-specific incidence of arrest.