Diltiazem improves resuscitation from experimental ventricular fibrillation in dogs.
OBJECTIVE
To determine the effect of diltiazem on survival immediately after cardiac arrest and cardiopulmonary resuscitation (CPR) in dogs.


METHODS
Prospective, double-blind, randomized trial.


METHODS
Laboratory at a large, university-affiliated medical center.


METHODS
Twenty-eight mongrel dogs, weighing 12 to 16 kg.


METHODS
After the administration of anesthesia, catheters were placed in the pulmonary artery, aortic arch, left ventricle, right ventricle, and great cardiac vein (12 dogs) for sample collection, pressure determinations, and induction of ventricular fibrillation. Dogs were randomized to receive either diltiazem, calcium chloride, or placebo (saline) either before or early during CPR. Dogs underwent 3 mins of unassisted fibrillatory arrest followed by 10 mins of standard CPR using a pneumatic device. After 13 mins of ventricular fibrillation, defibrillation was attempted repeatedly for less than or equal to 10 mins. Successful resuscitation was defined as an organized rhythm with an unassisted systolic BP of greater than 60 mm Hg for greater than or equal to 2 mins.


RESULTS
The resuscitation rate was significantly greater in diltiazem-treated animals (100%) than in those dogs receiving calcium (57%) or placebo (29%). Diltiazem-treated animals were resuscitated faster and required fewer defibrillation attempts than did dogs in the other groups. During CPR, coronary artery perfusion pressure and blood gases (arterial, venous, and myocardial) were similar among treatment groups.


CONCLUSIONS
Diltiazem improves the resuscitation from experimentally induced ventricular fibrillation when administered before or early during CPR. This response may have important clinical implications in the treatment of patients undergoing cardiac arrest and CPR.
Capparelli
E V
EV
Department of Pharmacy, Hartford Hospital, CT 06115.
Hanyok
J J
JJ
Dipersio
D M
DM
Kluger
J
J
Fieldman
A
A
Chow
M S
MS
D000704:Analysis of Variance; D000818:Animals; D001784:Blood Gas Analysis; D002122:Calcium Chloride / Q000008:administration & dosage; D006328:Cardiac Catheterization; D016887:Cardiopulmonary Resuscitation / Q000379:methods* / Q000706:statistics & numerical data; D004110:Diltiazem / Q000008:administration & dosage*; D004195:Disease Models, Animal; D004285:Dogs; D004311:Double-Blind Method; D004353:Drug Evaluation, Preclinical; D006439:Hemodynamics / Q000187:drug effects; D011897:Random Allocation; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000097:blood / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy*
D004110:Diltiazem; D002122:Calcium Chloride