Abstract 39: Atropine for Patients with Out-Of-Hospital Cardiac Arrest

Abstract

BACKGROUND AHA guidelines for cardiopulmonary resuscitation (CPR) have recommended that administration of atropine can be considered for asystole or pulseless electrical activity (PEA), because atropine has improved survival to hospital admission in a retrospective review (Ann Emerg Med, 1984), and is inexpensive, easy to administer, and has few side effects. However, there are insufficient data in humans. METHODS We assessed the effects of atropine in 7,443 adults patients with asystole or PEA arrest from the SOS-KANTO study: a prospective, multicenter, observational trial. The medications for asystole or PEA arrest were managed according to the advanced cardiovascular life support algorithm of the CPR guidelines (i.e. a 1-mg dose of epinephrine was administered intravenously every 3 to 5 minutes and a1-mg dose of atropine was administered intravenously every 3 to 5 minutes; maximum total of 3 doses). The primary endpoint was a favorable neurological outcome 30 days after cardiac arrest. RESULTS Of the 7,443 adult patients who had out-of-hospital cardiac arrest with asystole or PEA, I,708(23%) were treated with epinephrine and atropine and 5,735(77%) were treated with epinephrine. At baseline, the epinephrine and atropine group had significantly higher proportions of cardiac cause, witnessed arrest, and bystander CPR attempt than the epinephrine group. However, the two groups had a similar frequency of the favorable neurological outcome (0.3% in each group, p=0.805). Multiple logistic-regression analysis showed that the adjusted odds ratio for the favorable neurological outcome was 0.6 (95% CI 0.2–1.7, p=0.37) after epinephrine and atropine (compared with epinephrine). On the other hand, the epinephrine and atropine group had significantly higher rate of return of spontaneous circulation (ROSC) than the epinephrine group (35% vs. 23%, p<0.0001), and the adjusted odds ratio for ROSC was 1.6 (95% CI 1.4 –1.7, p<0.0001) after epinephrine and atropine (compared with epinephrine). CONCLUSIONS We demonstrated that administration of atropine during management of asystole or PEA arrest did not increase the frequency of favorable neurological outcome, although the atropine favored initial ROSC.