A simpler cardiac arrest model in rats.
Two disadvantages of electrical induction of cardiac arrest used currently are that it is a technically complicated procedure and the consequent thermal injury, which prompts us to search for a simpler method with less adverse effect to induce ventricular fibrillation (VF) in rats. Different potential (18, 24, 30, and 36 V) of alternating current (AC) were administered to elicit VF in 15 rats via pacing electrode placed in esophagus. Four minutes after onset of VF, conventional cardiopulmonary resuscitation (CPR) was initiated. Restoration of spontaneous circulation was defined as the return of supraventricular rhythm with a mean aortic pressure of 20 mm Hg or greater for a minimum of 5 minute. Ventricular fibrillation was achieved by short interval of AC stimulation in all of the rats. After the termination of prolonged AC stimulation, electrocardiogram indicated VF occurred in 6 of 15 rats, asystole in 3 of 15 rats and pulseless electrical activity in 6 of 15 rats. Before CPR, however, electrocardiogram indicated that only 2 of 15 and 4 of 15 animals remained in VF and pulseless electrical activity, respectively, whereas 9 of 15 animals presented as asystole. After CPR, 11 of 15 animals were resuscitated. Necropsy showed that there was no gross evidence of thermal injury on the surface layer of the heart. Therefore, development of a rat cardiac arrest model by transesophageal AC stimulation is simpler and less adverse effect, which may have practical significance for facilitating experimental investigation on cardiac arrest and CPR.
Chen
Meng-Hua
MH
Institute of Cardiovascular Diseases, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, PR China.
Liu
Tang-Wei
TW
Xie
Lu
L
Song
Feng-Qing
FQ
He
Tao
T
Zeng
Zhi-yu
ZY
Mo
Shu-Rong
SR
D000818:Animals; D016887:Cardiopulmonary Resuscitation; D004195:Disease Models, Animal; D004558:Electric Stimulation / Q000379:methods*; D005260:Female; D006323:Heart Arrest / Q000209:etiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D014693:Ventricular Fibrillation / Q000209:etiology* / Q000628:therapy