Cardiac arrest with VF: early defibrillation by BLS providers reduced risk of mortality

Clinical bottom line (level 2a)

  1. Patients with an out-of-hospital cardiac arrest who received defibrillation by basic life support providers were less likely to die (NNT = 15 at unknown) .
Auble et al: Annals of Emergency Medicine 1995; 25 (5): 642-648
Expires November 2003

The study

Systematic review of prospective studies of
  • Patients: with an out-of-hospital cardiac arrest due to ventricular fibrillation
  • Intervention: manual or automatic external defibrillators performed by providers trained in Basic Life Support (BLS)
  • Outcome: survival to discharge


    • Articles found in English using MEDLARS, 1980 to 1994 (search terms: automatic defibrillation, out-of-hospital defibrillation, early defibrillation, out-of-hospital cardiac arrest, emergency medicine and emergency medical technician (EMT) defibrillation ) and and searching reference lists of retrieved articles and reviews.

    Selection criteria: detailed in text
    Appraisal criteria: not given
    Articles excluded if:
    • not performed in the USA
    • no control group
    • information on patients in ventricular fibrillation unavailable


    7 studies were found (3 randomised controlled trials) involving 1827 patients
    The studies were not found to be significantly heterogeneous.

    The evidence

    Outcome Time to outcome CER RR
    (95% CI)    		 NNT
    (95% CI)
    death unknown 805/1009
    (79.8%)    		 0.915
    (0.876 to 0.955)     		15
    (10 to 28)

    Comments

    1. By limiting the search strategy to only one database and the English language means potentially important studies may have been missed.
    2. Note that the 3 studies that were randomised failed to show any difference between BLS defibrillation and standard BLS care.

    Citation

    1. Auble TE, Menegazzi JJ, Paris PM, et al: Effect of out-of-hospital defibrillation by life support providers on cardiac arrest mortality: a meta-analysis. Annals of Emergency Medicine 1995; 25 (5): 642-648
    Search Terms: ?
    Contributor: Chris Ball and Musab Hayatli, November 1999
    Reviewer: Dwight Peretz

    Clinical Question.
    Patient out-of-hospital cardiac arrest
    Intervention or Exposure defibrillation by BLS providers
    Outcome death