Effects of pericardial administration of lidocaineon hemodynamic responses.

背景资料：对于缺血性心脏病患者，尤其是非体外循环冠状动脉旁路移植术需要控制心率时，应尽量避免麻醉期间的心动过速反应。在不改变心脏收缩力的情况下降低心率是理想的心率控制方法。为了实现这一目的，我们尝试通过向心包腔注射局麻药来阻断心神经。研究方法：为了检查局部麻醉剂注入心包腔是否影响血流动力学和促凝性，我们研究了麻醉的机械通气的狗，肺导管到位。每10只犬用1%利多卡因2.5或5ml、2%利多卡因5ml或生理盐水灌注心包腔。在心包液中加入1%利多卡因的情况下，观察静脉注射阿托品或异丙肾上腺素的心脏反应。进一步研究了人参皂甙对心律失常的抑制作用 ...更多信息 在利多卡因的基础上，设置一个电刺激器，以决定诱发心律失常或室颤的电压。还使用6只犬测量利多卡因的血清浓度。结果如下：心包内注射利多卡因后，心率（HR）迅速下降（5分钟内约为对照组的80%，p<0.05），呈剂量依赖性，且显著降低，而每搏输出量（SV）无变化。在存在心包利多卡因的情况下，对异丙肾上腺素的HR反应是显著的，但与没有心包利多卡因的情况相似。然而，心率反应阿托品完全阻断心包利多卡因。利多卡因静脉注射与心包内灌注的血药浓度变化完全不同。静脉注射利多卡因后立即升高利多卡因的血药浓度，而心包灌注利多卡因后10分钟升高利多卡因的血药浓度。心包利多卡因使心律失常和室颤阈值由1.6V提高到2.2V，P<0.01。结论：心包给药利多卡因能很好地控制HR，并能保持对异丙肾上腺素的HR反应，但能完全阻断对阿托品的HR反应。对电刺激诱发的心律失常和室颤有抑制作用。这些结果表明，心包利多卡因可能适用于控制心率在非体外循环冠状动脉旁路移植术。少

Background : Tachycardiac responses during anesthesia should be better to avoid in the patients who have ischemic heart disease, especially during off-pump coronary artery bypass grafting surgery that needs the control of heart rate. Decrease of heart rate without change of cardiac contractility is ideal control of heart rate. In order to achieve this purpose, we tried to block the cardiac nerve with injection of local anesthetics given into the pericardial space. Methods : To examine whether a local anesthetic infusion into the pericardial space affects hemodynamics and arrhythmogenicity, we studied anesthetized, mechanical ventilated dogs having pulmonary catheter in place. We perfused the pericardial space with 2.5 or 5ml of 1% lidocaine, 5mi of 2% lidocaine, or normal saline solution for each 10 dogs. In the presence of pericardial lidocaine (1%), we observed the cardiac responses to intravenous atropine or isoproterenol. Further, to examine the inhibitory action to arrhythmia of p … More ericardial lidocaine, an electrical fibrillator was installed to decide the voltage of inducing arrhythmia or ventricular fibrillation. Also six dogs were used for measurement of serum concentration of lidocaine. Results : The pericardial administration of lidocaine soon decreased heart rate (HR) (about 80% from control within 5min, p<0.05), dose-dependently and significantly without changes in stroke volume (SV). In the presence of pericardial lidocaine, HR responses to isoproterenol were significant, but similar to that without pericardial lidocaine. However, HR response to atropine was completely blocked with pericardial lidocaine. Changes of plasma lidocaine concentration were completely different between intravenous injection and pericardial infusion. Intravenous injection of lidocaine elevated plasma concentration of lidocaine immediately, whereas the pericardial infusion of lidocaine elevated it 10min after its administration. The pericardial lidocaine rose the threshold for arrhythmia and ventricular fibrillation (from 1.6V to 2.2V, p<0.01). Conclusions : Pericardial administration of lidocaine well controlled HR, and could preserve HR responses to isoproterenol, but completely blocked HR responses to atropine. And it inhibited arrhythmia and ventricular fibrillation induced by electrical fibrillator. These results suggest that pericardial lidocaine may be suitable for control of HR during off-pump coronary artery bypass grafting surgery. Less