Abstract 1: A Randomised Placebo Controlled Trial of Adrenaline in Cardiac Arrest - the PACA Trial
Background: Adrenaline (Epinephrine) remains the primary pharmacological agent in cardiac arrest. Despite a total absence of any experimental trials to establish efficacy, adrenaline is considered standard of care in resuscitation.
Methods: We undertook a double-blind randomised placebo controlled trial of adrenaline in out-of-hospital cardiac arrest in Perth, Western Australia between August 2006 and November 2009. Patients were randomly assigned to receive either 1 ml aliquots of adrenaline 1:1000 or Sodium Chloride (0.9%) by means of computerised random number generator. Primary outcome was survival to hospital discharge and secondary outcomes included return of spontaneous circulation (ROSC) and neurological outcome (Cerebral Performance Category Score) at hospital discharge. Odds ratios (OR) and 95% confidence intervals were derived for these outcomes and analysis was on an intention to treat basis.
Results: During the study period paramedics attended 4107 cardiac arrests of which resuscitation was commenced in 1586 (38.6%) patients. Of these 602 (37.9%) were enrolled into the study with a further 67 (11.1%) being excluded after randomisation. Of the remaining 535 patients 262 (48.9%) and 273 (51.0%) received placebo or adrenaline respectively. The percentage male (70.6% versus 74.8%); mean age (64.8 versus 65.4 years) and percentage of patients who received bystander CPR (55.7% versus 53.1%) were similar for the adrenaline and placebo groups respectively. ROSC was achieved in 83 (30.4%) patients receiving adrenaline and 29 (11.1%) receiving placebo - OR= 3.51 [95% CI 2.21 to 5.58]. Survival to hospital discharge occurred in 11 (4.1%) and 5 (1.9%) of the adrenaline and placebo patients respectively - OR= 2.16 [95% CI: 0.74 to 6.30]
Conclusions: The use of adrenaline in cardiac arrest was associated with a significant increase in the proportion of patients achieving ROSC however this improvement did not extend to survival to hospital discharge. As our results are unable to rule out a clinically meaningful benefit of adrenaline in terms of survival to hospital discharge, further investigation into the post resuscitation period for those achieving ROSC is required in order to identify management strategies to improve survival.
- © 2010 by American Heart Association, Inc.