不同浓度异氟烷对犬心血管效应的比较

Comparison of cardiovascular effects of different concentrations of isoflurane on dogs

旨在比较不同浓度异氟烷对犬心血管系统的影响,为临床选择提供依据。将15只健康小型犬随机分为3组,分别接受2%、3%、4%浓度的异氟烷维持麻醉,对3种浓度下的心血管效应进行评估。结果显示:麻醉后各组的心率无显著差异;各组的收缩压、舒张压均低于正常范围。4%浓度组的平均动脉压、舒张压与基础值比较差异均极显著(P<0.01);Ⅱ导联下,3组的心律和心电图波形基本正常;低剂量组的乳酸脱氢酶(LDH)水平极显著下降(P<0.01),而4%组的心肌酶各项指标无显著变化。麻醉后3个试验组的眼压与基础值相比,均呈显著差异(P<0.05),且随麻醉时间延长出现极显著差异(P<0.01)。研究表明,使用不同浓度的异氟烷进行维持麻醉,犬的心血管系统受到抑制作用,且具有剂量依赖性,临床应用高达4%浓度异氟烷麻醉时应注意监测。

This study was to compare the effects of different concentrations of isoflurane on the cardiovascular system of dogs,and to pro-vide evidence for veterinary clinical selection of appropriate concentrations of isoflurane.Fifteen healthy small dogs were obtained and ran-domly divided into three groups receiving isoflurane maintenance anesthesia at concentrations of 2%,3%,and 4%,respectively,and then the cardiovascular effects of the three concentrations were evaluated.The results showed that the heart rate of all the groups was not signifi-cantly affected after anesthesia.Their systolic and diastolic blood pressures were lower than the normal range.The mean blood pressure and diastolic blood pressure of the 4%concentration group were significantly different from the basic value(P<0.01).Under theⅡlead,the rhythm and electrocardiogram waveform of the three treated groups were basically normal.The lactate dehydrogenase(LDH)decreased signif-icantly in the low dose group(P<0.01),but the myocardial enzyme index in the 4%concentration group did not change significantly.The intraocular pressure after anesthesia was significantly different from the basic value(P<0.05)and significantly different with the increase in anesthesia time(P<0.01).The present studies indicated that the cardiovascular system of dogs was similarly affected by maintenance anes-thesia with different concentrations of isoflurane,which exhibited a dose-dependent inhibition effect and should be monitored at a high con-centration of 4% isoflurane.