Optimizing the duration of CPR prior to defibrillation improves the outcome of CPR in a rat model of prolonged cardiac arrest.
OBJECTIVE
This study was to investigate whether optimal duration of CPR prior to defibrillation could be guided by Amplitude Spectrum Analysis (AMSA) in the setting of prolonged VF on outcome of CPR.


METHODS
VF was induced in thirty Sprague-Dawley rats and untreated for 8 minutes. Animals were then randomized into 3 groups prior to CPR: The duration of CPR prior to defibrillation was guided by AMSA (CC+AMSA); guidelines-based with delayed defibrillation that simulated the AED algorithm (GL+AED); and guidelines-based with immediate shock (GL+shock ready).


RESULTS
Regardless of groups, the majority of the animals (85%) required over 5 min of CPR to achieve restoration of spontaneous circulation (ROSC). Significantly greater rate of ROSC after first defibrillation (70% vs 0%, p < 0.01), lesser CPR interruptions and the number of defibrillations were observed in the CC+AMSA group when compared to both guidelines-based groups (p < 0.001). This was associated with a significantly better post-resuscitation myocardial and neurological function and longer durations of survival.


CONCLUSIONS
After prolonged VF, optimal duration of CPR prior to defibrillation guided by AMSA improves the outcome of CPR.
Weil Institute of Critical Care Medicine, Rancho Mirage, CA 92270, USA.
Shijie
S
Sun
Yinlun
Y
Weng
Xiaobo
X
Wu
Katherine
K
Tang
Sen
S
Ye
Wei
W
Chen
Max Harry
MH
Weil
Wanchun
W
Tang
D000818:Animals; D016887:Cardiopulmonary Resuscitation / Q000379:methods* / Q000592:standards; D004195:Disease Models, Animal; D004554:Electric Countershock / Q000592:standards*; D004562:Electrocardiography; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000209:etiology / Q000628:therapy*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000150:complications / Q000503:physiopathology / Q000628:therapy