title: Effect of location of out-of-hospital cardiac arrest on survival outcomes.
abstract: BACKGROUND
  This study aims to study how the effect of the location of patient collapses from cardiac arrest, in the residential and non-residential areas within Singapore, relates to certain survival outcomes.
  
  
  METHODS
  A retrospective cohort study of data were done from the Cardiac Arrest and Resuscitation Epidemiology (CARE) project. Out-of- hospital cardiac arrest (OHCA) data from October 2001 to October 2004 (CARE) were used. All patients with OHCA as confirmed by the absence of a pulse, unresponsiveness and apnoea were included. All events had occurred in Singapore. Analysis was performed and expressed in terms of the odds ratio (OR) and the corresponding 95% confidence interval (CI).
  
  
  RESULTS
  A total of 2375 cases were used for this analysis. Outcomes for OHCA in residential areas were poorer than in non-residential areas-1638 (68.9%) patients collapsed in residential areas, and 14 (0.9%) survived to discharge. This was significantly less than the 2.7% of patients who survived after collapsing in a non-residential area (OR 0.31 [0.16 - 0.62]). Multivariate logistic regression analysis showed that location alone had no independent effect on survival (adjusted OR 1.13 [0.32 - 4.05]); instead, underlying factors such as bystander CPR (OR 3.67 [1.13 - 11.97]) and initial shockable rhythms (OR 6.78 [1.95 - 23.53]) gave rise to better outcomes.
  
  
  CONCLUSIONS
  Efforts to improve survival from OHCA in residential areas should include increasing CPR by family members, and reducing ambulance response times.
authors.affiliation: Department of Acute Care and Emergency, Khoo Teck Puat Hospital, Singapore.
authors.forename: E Shaun
authors.initials: ES
authors.lastname: Goh
authors.forename: Benjamin
authors.initials: B
authors.lastname: Liang
authors.forename: Stephanie
authors.initials: S
authors.lastname: Fook-Chong
authors.forename: Nur
authors.initials: N
authors.lastname: Shahidah
authors.forename: Swee Sung
authors.initials: SS
authors.lastname: Soon
authors.forename: Susan
authors.initials: S
authors.lastname: Yap
authors.forename: Benjamin
authors.initials: B
authors.lastname: Leong
authors.forename: Han Nee
authors.initials: HN
authors.lastname: Gan
authors.forename: David
authors.initials: D
authors.lastname: Foo
authors.forename: Lai Peng
authors.initials: LP
authors.lastname: Tham
authors.forename: Rabind
authors.initials: R
authors.lastname: Charles
authors.forename: Marcus E H
authors.initials: ME
authors.lastname: Ong
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000552:Ambulances; D016887:Cardiopulmonary Resuscitation / Q000706:statistics & numerical data*; D015331:Cohort Studies; D004632:Emergency Medical Services / Q000706:statistics & numerical data*; D005260:Female; D005843:Geography; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality*; D012111:Residence Characteristics / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012846:Singapore / Q000453:epidemiology; D061665:Time-to-Treatment / Q000706:statistics & numerical data*; D016896:Treatment Outcome