Brown C G, Griffith R F, Van Ligten P, Hoekstra J, Nejman G, Mitchell L, Dzwonczyk R
Department of Emergency Medicine, Ohio State University, Columbus 43210.
Ann Emerg Med. 1991 Jul;20(7):787-9. doi: 10.1016/s0196-0644(05)80843-1.
Current American Heart Association guidelines recommend immediate defibrillation of ventricular fibrillation. When this is unsuccessful, there are no guidelines to help determine the optimum time at which to defibrillate after the administration of an alpha-adrenergic agonist. Previous studies have shown that the median frequency of the ventricular fibrillation ECG signal correlates with myocardial perfusion during CPR. We hypothesized that median frequency could predict the success of defibrillation and thus accurately determine the most appropriate time at which to defibrillate during ventricular fibrillation.
Twenty-two mixed-breed swine weighing more than 15 kg were studied.
Ventricular fibrillation was induced electrically, and the ventricular fibrillation ECG signal was analyzed using fast Fourier analysis. After ten minutes of ventricular fibrillation, mechanical CPR was begun. After three minutes of CPR, the animals received one of three alpha-adrenergic agonists and CPR was continued. Defibrillation was attempted three and one-half minutes after drug administration. The average median frequency 20 seconds before defibrillation was calculated. Sensitivity and specificity of median frequency with respect to defibrillation success were determined.
A median frequency of 9.14 Hz had a sensitivity of 100% and a specificity of 92.31% in predicting the results of defibrillation in this model.
The median frequency may serve as a valuable parameter to guide defibrillation therapy during ventricular fibrillation.
美国心脏协会目前的指南推荐对心室颤动立即进行除颤。当这一方法未成功时，没有指南可帮助确定在给予α-肾上腺素能激动剂后进行除颤的最佳时间。先前的研究表明，心室颤动心电图信号的中位频率与心肺复苏期间的心肌灌注相关。我们假设中位频率可以预测除颤的成功率，从而准确确定心室颤动期间进行除颤的最合适时间。
对22只体重超过15千克的杂种猪进行了研究。
通过电刺激诱发心室颤动，并使用快速傅里叶分析对心室颤动心电图信号进行分析。心室颤动10分钟后开始机械心肺复苏。心肺复苏3分钟后，动物接受三种α-肾上腺素能激动剂中的一种，并继续进行心肺复苏。在给药3分半钟后尝试除颤。计算除颤前20秒的平均中位频率。确定中位频率对于除颤成功的敏感性和特异性。
在该模型中，9.14赫兹的中位频率在预测除颤结果时的敏感性为100%，特异性为92.31%。
中位频率可能是指导心室颤动期间除颤治疗的一个有价值的参数。
