title: The duration of cardiopulmonary resuscitation in emergency departments after out-of-hospital cardiac arrest is associated with the outcome: A nationwide observational study.
abstract: OBJECTIVE
  The appropriate duration of cardiopulmonary resuscitation (CPR) for patients who experience out-of-hospital cardiac arrest (OHCA) remains unknown. This study aimed to evaluate the duration of CPR in emergency departments (EDs) and to determine whether the institutions' median duration of CPR was associated with survival-to-discharge rate.
  
  
  METHODS
  A cohort of adult patients from a nationwide OHCA registry was retrospectively evaluated. The main variable was the median duration of CPR for each ED (institutional duration), and the main outcome was survival to discharge. Multivariable logistic regression analysis was performed to adjust for individual and aggregated confounders.
  
  
  RESULTS
  Among the 107,736 patients who experienced OHCA between 2006 and 2010, 30,716 (28.5%) were selected for analysis. The median age was 65 years, and 67.1% were men. The median duration of CPR for all EDs was 28 min, ranging from 11 to 45 min. EDs were categorized into 3 groups according to their institutional duration of CPR: groups A (< 20 min), B (20-29 min), C (≥ 30 min). The observed survival rates of the 3 groups were 2.11%, 5.20%, and 5.62%, respectively. Compared with group B, the adjusted difference (95% confidence interval) for survival to discharge was 3.01% (1.90-4.11, P<0.001) for group A, and 0.33% (-0.64 to 1.30, P=0.51) for group C.
  
  
  CONCLUSIONS
  The duration of CPR varied widely among hospitals. The institutional duration of CPR less than 20 min was significantly associated with lower survival-to-discharge rate.
authors.affiliation: Department of Emergency Medicine, Samsung Medical Center, Republic of Korea.
authors.forename: Won Chul
authors.initials: WC
authors.lastname: Cha
authors.affiliation: Department of Emergency Medicine, Seoul National University College of Medicine, Republic of Korea.
authors.forename: Eui Jung
authors.initials: EJ
authors.lastname: Lee
authors.affiliation: Department of Social and Preventive Medicine, Inha University School of Medicine, 7-206, 3-ga, Shinheung-dong, Jung-gu, Incheon, 400-712, Republic of Korea. Electronic address: cyberdoc@inha.ac.kr.
authors.forename: Seung-Sik
authors.initials: SS
authors.lastname: Hwang
mesh_terms: D000328:Adult; D000368:Aged; D016887:Cardiopulmonary Resuscitation / Q000379:methods* / Q000592:standards; D004632:Emergency Medical Services / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality / Q000628:therapy*; D012042:Registries; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D016896:Treatment Outcome
keywords: CPR; OHCA; Resuscitation