不同剂量的肾上腺素在犬心肺复苏中所起作用的比较研究

目的：寻找肾上腺素用于心肺复苏的最佳剂量。方法：选择成年杂种犬６０条，随机分为６组，造成心梗模型后致颤，分别给予０．０２、０．０５、０．０７５、０．１、０．２、０．３ｍｇ／ｋｇ体重的肾上腺素进行心肺复苏，比较心肺复苏的成功率，恢复自主循环的时间及自主循环恢复１ｍｉｎ后血流动力学指标的变化；并以电镜技术观察肾上腺素对心肌组织的影响。结果：０．０７５ｍｇ／ｋｇ和０．１ｍｇ／ｋｇ体重组复苏的成功率明显高于其他各组（Ｐ＜０．０５），且此两组自主循环的恢复时间明显短于其他各组（Ｐ＜０．０５）；各组复苏１ｍｉｎ后血流动力学指标的变化：随着剂量的增加，收缩压、舒张压、左室收缩末压逐渐增加，但心输出量和冠脉血流量却在０．０７５ｍｇ／ｋｇ体重组达最高，与其他各组比较Ｐ值均＜０．０５，超过０．１ｍｇ／ｋｇ心输出量和冠脉血流量不再继续增加；电镜所见：各组非梗塞区的心肌组织只有轻微改变，与所用的肾上腺素的剂量无关。结论：犬心肺复苏过程中应用０．０７５ｍｇ／ｋｇ和０．１ｍｇ／ｋｇ体重的肾上腺素为最佳剂量

Comparison of different doses of epinephrine in theresuscitation of cardiac arrest in dogs

Objective:In order to evaluate the efficacy of different doses of epinephrine on cardiac arrest in dogs.Methods:Sixty adult dogs were anaesthetized and monitored by central venous catheter,intra arterial catheter,and ECG.A left lateral thoracotomy was performed and the proximal left an terior descending artery was ligated.After myocardial ischemia 24 min,ventricular fibrillation was abtained by application of 6-V AC.Mechanical ventilation was stopped.Total arrest time was three min.All animals were randomly divided into six groups,and received epinephrine in doses of 0.02,0.05,0.075,0.1,0.2,0.3 ρB/ mg·kg-1by central vein respectively.Results:The results showed that the return rates of spontaneous circulation (RSC) in groups of 0.075 ρB/ mg·kg-1 and 0.1 ρB/ mg·kg-1 were significantly higher than those in other groups (P<005).The SBP,DBP and LVSP increased with doses increasing after one minutes of RSC,but the CO and HMBF in groups of 0.075 ρB/ mg·kg-1 and 0.1 ρB/ mg·kg-1 were signficantly higher than those in other groups (P<005).No histopathological changes in normal cardiac muscle cells were observed under electron microscope.Conclusion:These data suggest that the most suitable doses in cardiopulmonary resuscitation (CPR) of cardiac arrest are 0.075￣0.1 ρB/ mg·kg-1.