Standard and higher doses of atropine in a canine model of pulseless electrical activity.
OBJECTIVE
To determine whether standard or increased doses of atropine improve the return of spontaneous circulation (ROSC) rate in a canine model of pulseless electrical activity (PEA).


METHODS
A prospective, controlled, blinded laboratory investigation was performed using an asphyxial canine cardiac arrest model. After the production of asphyxial PEA, 75 dogs remained in untreated PEA for 10 minutes and then were randomized to receive placebo (group 1) or one of four doses of atropine (group 2, 0.04 mg/kg; group 3, 0.1 mg/kg; group 4, 0.2 mg/kg; group 5, 0.4 mg/kg). All the animals received mechanical external CPR and epinephrine (0.02 mg/kg every 3 minutes) throughout resuscitation.


RESULTS
The ROSC rates were not significantly different between the groups (group 1, 73%; group 2, 67%; group 3, 40%; group 4, 47%; group 5, 27%; p = 0.06). The heart rates and hemodynamics during resuscitation were not significantly different between the groups.


CONCLUSIONS
In this canine model of asphyxial PEA cardiac arrest, standard-dose atropine did not improve ROSC rates, compared with placebo. Increasing doses of atropine tended to decrease ROSC rates, compared with placebo and standard-dose atropine.
DeBehnke
D J
DJ
Department of Emergency Medicine, Medical College of Wisconsin, Milwaukee 53226, USA.
Swart
G L
GL
Spreng
D
D
Aufderheide
T P
TP
D000704:Analysis of Variance; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D001237:Asphyxia / Q000503:physiopathology; D001285:Atropine / Q000008:administration & dosage* / Q000627:therapeutic use; D016887:Cardiopulmonary Resuscitation / Q000379:methods; D004195:Disease Models, Animal; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004562:Electrocardiography; D005260:Female; D006323:Heart Arrest / Q000188:drug therapy* / Q000503:physiopathology; D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology; D008297:Male; D011446:Prospective Studies; D011897:Random Allocation
D000889:Anti-Arrhythmia Agents; D001285:Atropine