Viana J da S, Morais J, Castro G, Figueiredo F, Godinho A M, Fonseca P, Freitas M, Providência L A
Laboratório de Experimentação Animal dos Hospitais, Universidade de Coimbra, HUC.
Rev Port Cardiol. 1994 Sep;13(9):671-5, 640.
Several studies suggest that anaesthetic drugs influence the haemodynamic effects of the antiarrhythmic drugs. The aim of this study was to compare the haemodynamic effects of a standard dose of propafenone (1.5 mg/kg) on dogs anaesthetized with halothane or with isoflurane.
Randomized laboratory animal study.
Six dogs were anaesthetized with 1% of halothane-Group I, and six dogs with an equianaesthetic dosage of isoflurane (1.5%)-Group II. Dogs breathed in spontaneous ventilation. Haemodynamic monitoring was performed with a femural arterial catheter and a flow-directed pulmonary artery catheter and cardiac output was measured by thermodilution. After a haemodynamic assessment considered as initial a bolus of 1.5 mg/kg of propafenone was given during a period of 30 seconds and similar assessments were made 5, 15, 30 and 60 minutes after.
Before propafenone, heart rate was significantly higher in Group II-isoflurane (p < 0.05). After propafenone we found: In both Groups, a decrease in the cardiac output (p < 0.05) with the mean arterial pressure maintained; in Group I (halothane) a decrease in the stroke volume (p < 0.05) which was not found in Group II (p = ns); In Group II (isoflurane) a decrease in heart rate (p < 0.05) not found in Group I (p = ns). All the changes were higher at the 5th minute values. 30th minute and 60th minute values were not significantly different from initial values.
In dogs anaesthetized with halothane 1.2 MAC a reduction in the stroke volume, resulting in a cardiac output decrease, was observed, suggesting that propafenone increases the negative inotropic action of halothane. In dogs anaesthetized with isoflurane 1.2 MAC the decrease in cardiac output was similar to the decrease in heart rate, and therefore no reduction in the stroke volume was observed. The decrease in the heart rate found in this group but not in the halothane group was probably related with the beta-blocker action of the propafenone. Looking to the systemic vascular resistances, our study suggested that propafenone didn't have any vasodilator effect during halogenated anaesthesia.
多项研究表明麻醉药物会影响抗心律失常药物的血流动力学效应。本研究旨在比较标准剂量的普罗帕酮（1.5毫克/千克）对用氟烷或异氟烷麻醉的犬的血流动力学效应。
随机实验室动物研究。
6只犬用1%氟烷麻醉——第一组，6只犬用等效麻醉剂量的异氟烷（1.5%）麻醉——第二组。犬自主呼吸。用股动脉导管和漂浮导管进行血流动力学监测，通过热稀释法测量心输出量。在进行了一次被视为初始评估的血流动力学评估后，在30秒内给予1.5毫克/千克的普罗帕酮推注，在给药后5、15、30和60分钟进行类似评估。
在给予普罗帕酮之前，第二组（异氟烷）的心率显著更高（p < 0.05）。给予普罗帕酮后我们发现：在两组中，心输出量均下降（p < 0.05），平均动脉压维持不变；在第一组（氟烷）中，每搏量下降（p < 0.05），而在第二组中未发现此现象（p = 无显著性差异）；在第二组（异氟烷）中，心率下降（p < 0.05），在第一组中未发现此现象（p = 无显著性差异）。所有变化在第5分钟时最为明显。第30分钟和第60分钟的值与初始值无显著差异。
在用1.2倍最低肺泡有效浓度氟烷麻醉的犬中，观察到每搏量降低，导致心输出量下降，这表明普罗帕酮增强了氟烷的负性肌力作用。在用1.2倍最低肺泡有效浓度异氟烷麻醉的犬中，心输出量的下降与心率的下降相似，因此未观察到每搏量降低。在该组中发现但在氟烷组中未发现的心率下降可能与普罗帕酮的β受体阻滞作用有关。从全身血管阻力来看，我们的研究表明普罗帕酮在卤代麻醉期间没有任何血管舒张作用。
