The effect of time to defibrillation and targeted temperature management on functional survival after out-of-hospital cardiac arrest

Resuscitation. 2014 Nov;85(11):1623-8. doi: 10.1016/j.resuscitation.2014.07.010. Epub 2014 Aug 12.


Background: Cardiac arrest physiology has been proposed to occur in three distinct phases: electrical, circulatory and metabolic. There is limited research evaluating the relationship of the 3-phase model of cardiac arrest to functional survival at hospital discharge. Furthermore, the effect of post-cardiac arrest targeted temperature management (TTM) on functional survival during each phase is unknown.

Objective: To determine the effect of TTM on the relationship between the time of initial defibrillation during each phase of cardiac arrest and functional survival at hospital discharge.

Methods: This was a retrospective observational study of consecutive adult (≥18 years) out-of-hospital cardiac arrest (OHCA) patients with initial shockable rhythms. Included patients obtained a return of spontaneous circulation (ROSC) and were eligible for TTM. Multivariable logistic regression was used to determine predictors of functional survival at hospital discharge.

Results: There were 20,165 OHCA treated by EMS and 871 patients were eligible for TTM. Of these patients, 622 (71.4%) survived to hospital discharge and 487 (55.9%) had good functional survival. Good functional survival was associated with younger age (OR 0.94; 95% CI 0.93-0.95), shorter times from collapse to initial defibrillation (OR 0.73; 95% CI 0.65-0.82), and use of post-cardiac arrest TTM (OR 1.49; 95% CI 1.07-2.30). Functional survival decreased during each phase of the model (65.3% vs. 61.7% vs. 50.2%, P<0.001).

Conclusion: Functional survival at hospital discharge was associated with shorter times to initial defibrillation and was decreased during each successive phase of the 3-phase model. Post-cardiac arrest TTM was associated with improved functional survival.

Keywords: Neurological outcome; Out-of-hospital cardiac arrest; Post-cardiac arrest care; Targeted temperature management.

Publication types

  • Observational Study

MeSH terms

  • Adult
  • Aged
  • Body Temperature Regulation
  • Continuity of Patient Care
  • Databases, Factual
  • Electric Countershock / methods*
  • Electric Countershock / mortality
  • Emergency Medical Services / methods
  • Female
  • Follow-Up Studies
  • Hospital Mortality*
  • Hospitalization / statistics & numerical data
  • Humans
  • Hypothermia, Induced / methods*
  • Hypothermia, Induced / mortality
  • Logistic Models
  • Male
  • Middle Aged
  • Ontario
  • Out-of-Hospital Cardiac Arrest / mortality*
  • Out-of-Hospital Cardiac Arrest / therapy*
  • Patient Discharge / statistics & numerical data
  • Retrospective Studies
  • Risk Assessment
  • Survival Rate
  • Survivors
  • Time-to-Treatment / standards*
  • Time-to-Treatment / trends