Cardiac arrest: increasing doses of epinephrine, increasing age, out-of-hospital arrest and a longer time to resuscitation were associated with a poor neurologic outcome

Clinical bottom line (level 2b)

  1. 85% of patients who had a cardiac arrest will had return of spontaneous circulation.
  2. Two thirds of patients who had a cardiac arrest had an unfavourable neurologic outcome.
  3. Patients who
    • received 5 mg of epinephrine or more (NNF = 22 for 6 months)
    • time of collapse to any resuscitation >2 minutes (NNF = 19 for 6 months)
    • time between initial resuscitation and return of circulation >10 minutes (NNF = 83 for 6 months)
    • increasing age (NNF = 48 for 6 months)
    • out-of-hospital cardiac arrest (NNF = 3 for 6 months)
    during a VF cardiac arrest were at increased risk of brain damage.
Behringer et al: Annals of Internal Medicine 1998; 129: 450-456
Expires October 2003

The study

Retrospective cohort study with blinded outcomes, adjusted for confounding factors, not validated in an independent set of patients.

Setting: university hospital, Austria

178 patients (aged 50 to 71; mean 61, 83% male) with witnessed, nontraumatic, normothermic VF cardiac arrest (defined as absence of spontaneous respiration and palpable pulses)

Excluded if
  • spontaneous circulation returned within 3 minutes after the initial 3 countershocks
  • additional cardiac arrest within the next 6 months
  • severe heart failure
  • poor cerebral performance



    • Factors studied:
  • epinephrine dose, age, time to initiation of CPR, time to return of spontaneous circulation, out-of-hospital cardiac arrest
  • cumulative dose of epinephrine > 5 mg total dose administered during advanced cardiac life support
  • time of collapse to any resuscitation >2 minutes
  • time between initial resuscitation and return of spontaneous circulation or termination >10 minutes
  • increasing age
  • out-of-hospital cardiac arrest




    • Logistic regression analysis performed to adjust for confounding factors (age, sex, BMI, by-stander assisted basic life support, out-of-hospital cardiac arrest, time to initiation of CPR and time to return of spontaneous circulation)

    ?100% followed for 6 months
    Outcomes studied:
  • return of spontaneous circulation return of palpable arterial pulse
  • unfavourable neurological outcome severe disability or coma

    • The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)
    return of spontaneous circulation 6 months 151/178 85%
    (80% to 90%)
    unfavourable neurological outcome 6 months 88/151 58.3%
    (50.4% to 66.1%)

    prognostic factor for
    unfavourable neurological outcome     		time to outcome control rate (%) adjusted OR
    (95% CI)    		 NNF+
    (95% CI)
    cumulative dose of epinephrine 6 months 38/110
    (34.6%)     		1.22
    (1.01 to 1.46)     		22
    (11 to 443)
    time of collapse to any resuscitation >2 minutes 6 months 29/78
    (37.3%)     		1.25
    (1.08 to 1.45)     		19
    (11 to 55)
    time between initial resuscitation and return of spontaneous circulation or termination >10 minutes 6 months 28/62
    (45.2%)     		1.05
    (1.01 to 1.10)     		83
    (42 to 406)
    increasing age 6 months 88/151
    (58.3%)     		1.09
    (1.04 to 1.13)     		48
    (34 to 105)
    out-of-hospital cardiac arrest 6 months 88/151
    (58.3%)     		12.3
    (1.23 to 122)     		3
    (2 to 20)

    • Numbers needed to follow for increasing age and out-of-hospital arrest are overestimated due to having to use the overall control rate to calculate them.

    Citation

    1. Behringer W, Kittler H, Sterz F, et al: cumulative epinephrine dose during cardiopulmonary resuscitation and neurologic outcome. Annals of Internal Medicine 1998; 129: 450-456
    Contributor: Chris Ball and Clare Wotton, October 1999
    Reviewer: Bruce Arroll

    Clinical Question.
    Patient patients with cardiac arrest
    Intervention or Exposure epinephrine dose, age, time to CPR, time to return on spontaneous circulation, out-of-hospital arrest
    Outcome neurologic outcome