Summary: | Abstract Background Cardiac Arrest (CA) is one of the leading causes of mortality worldwide. The present study aimed to establish a simple and stable rat model of CA induced by transesophageal cardiac pacing for the investigation of cerebral resuscitation. Materials and Methods A total of 26 healthy adult male Sprague-Dawley rats were randomly allocated into two groups: Sham-operated (n = 6) and experimental (n = 20) groups. High-frequency cardiac pacing (50 Hz, 2 ms and 30 V) was maintained for 3 min to induce CA. Providing CA was not achieved, an additional 2 min of pacing was performed 30 min later. After 4 min following the onset of CA, Cardiopulmonary Resuscitation (CPR) was initiated. Results CA was successfully induced in all 20 rats by this setting of high-frequency cardiac pacing. Among them, CA was induced in six rats after 2 min of pacing; the remaining 14 rats underwent CA after 3 min of pacing. When electrical stimulation was terminated the rate of Pulseless Electrical Activity (PEA) was 85% (17/20), the rate of Ventricular Fibrillation (VF) was 15% (3/20) and no asystole occurred. Of the 17 PEA rats, 16 were successfully resuscitated and the average duration of CPR was 106.75 ± 30.81 s. A total of three rats succumbed within 24 h, and one rat succumbed between 24 and 48 h following successful resuscitation; 12 rats survived to <72 h. In addition, three rats with VF were successfully resuscitated and the average duration of CPR was 264.33 ± 130.40 s; one rat succumbed between 24 and 48 h following successful resuscitation, and two rats survived to <72 h. The 72 h-survival rate was 74%. No notable injury the esophagus was observed in the rats. Compared with the Sham group, the neurological function of the CA group was significantly impaired (p < 0.05); cells in the hippocampal CA1 region of the CA group were significantly damaged (p < 0.05). Conclusion The model of CA induced by transesophageal cardiac pacing in the present study is easy and replicable. Therefore, this model may be used for experimental research into cerebral resuscitation.
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