Abstract: Objective To discuss physiopathological changes in a rabbit model of asphyxia induced cardiac arrest and advantages of the model applied to the study of post-cardiopulmonary resuscitation. Methods Fifteen clean-grade adult rabbits were included in this study. Cardiac arrest was induced by asphyxia, the duration of which was 7 minutes. The changes of blood pressure and electrocardiogram were observed before and after cardiac arrest. And the time of cardiac arrestˇ˘the time to restoration of spontaneous circulation(ROSC)、the time to restoration of spontaneous breath, and the electrocardiogram when cardiac arrest occurred were recorded. The rate of restoration of spontaneous circulation and survival rate in 6 h, 12 h, 24 h, and 48 h were calculated. The arterial blood gas analysis was tested before and after cardiac arrest. Results ①MAP before closing trachea is 116.18±8.89 mmHg, at the moment of restoration of spontaneous circulation, was 121.03±16.75 mmHg, at 15 minutes since that, was 90.92±13.68 mmHg, and remained at that level thereafter. According to the electrocardiogram recorded at the moment of cardiac arrest, we found 2 cases of ventricular fibrillation, 11 cases of electromechanical dissociation, and 2 cases of asystole with a straight line. The electrocardiogram showed the progression of ST segment elevation and recovery from the restoration of spontaneous circulation to 30 minutes. ②The rate of restoration of spontaneous circulation from cardiac arrest was 100%(15/15), and the time was 147.60±22.09 s. The time to restoration of spontaneous breath was 403.33±130.18 s. The survival rate in 6h, 12h, 24h, and 48h were 93.33%(14/15), 73.33%(11/15), 53.33%(8/15) and 26.67%(4/15) separately. ③At the moment of restoration of spontaneous circulation, pH of the arterial blood gas analysis obviously decreased (P<0.05), and PaO₂、PaCO₂ and lactic acid obviously increased(P<0.05), compared with those before asphyxia. Conclusion The rabbit model of asphyxia induced cardiac arrest can simulate the characteristics of the pathophysiological changes in clinical cardiopulmonary resuscitation. The main adventages include the research needs of laboratory measurements and hemodynamic monitoring, the experimental operation is easy to grasp and without thoracotomy.

Key words: Cardiac arrest, Animal model, Asphyxia, Cardiopulmonary resuscitation