Relative importance of predictors of survival in OHCA

Al-Dury N, Ravn-Fischer A, Hollenberg J, et al. Identifying the relative importance of predictors of survival in out of hospital cardiac arrest: a machine learning study. Scand J Trauma Resusc Emerg Med. 2020;28(1):60. Published 2020 Jun 25. doi:10.1186/s13049-020-00742-9

Overall population

The top five factors to predict survival in order of importance were:

  1. initial rhythm
  2. age
  3. early CPR (time to CPR and CPR before the arrival of EMS)
  4. time from EMS dispatch until EMS arrival (EMS response time)
  5. place of cardiac arrest

The largest difference in importance was noted between the initial rhythm and the remaining predictors.

The five factors that were of least importance were: sex, time during the day when OHCA took place, time from emergency call to EMS dispatch (procedure time at the dispatch center), region where and calendar year when OHCA took place.

Shockable rhythm

The five most important predictors were:

  1. time to defibrillation
  2. age
  3. defibrillation (yes/no)
  4. place of cardiac arrest
  5. time from cardiac arrest to CPR

The largest difference in importance was noted between time from cardiac arrest to defibrillation and age.

The five least important predictors were the same as for the overall population.

Non-shockable rhythms

The most important predictors were

  1. age
  2. defibrillation before EMS arrival
  3. time to EMS arrival
  4. place of cardiac arrest
  5. cause of cardiac arrest
,