血液稀释下多培沙明、多巴胺和多巴酚丁胺对血流动力学的影响

Effectsofdopexamine,dopamineanddobutamineonhemodynamicsfolowingacuteisovolemichemodi┐lutionindog

急性血液稀释犬１８只随机分为多培沙明（ＤＰＸ）、多巴胺（ＤＯＰ）和多巴酚丁胺（ＤＯＢ）三组，每组６只。观察上述三种药物对血流动力学影响。在血液稀释前后三组分别依次输入ＤＰＸ、ＤＯＰ和ＤＯＢ各１、２和７μｇ·ｋｇ－１·ｍｉｎ－１，用电磁流量计及左室插管法测定相应血流动力参数。在注药前测定并记录心排血量（ＣＯ）、左室内压上升最大速率（ＬＶｄｐ／ｄｔｍａｘ）、升主动脉收缩压（ＡＳＰ）、舒张压（ＡＤＰ）、平均动脉压（ＭＡＰ）、左室舒张末压（ＬＶＥＤＰ）。同时测定血清离子、动脉和中心静脉血气。计算出每搏量（ＳＶ）、总外周血管阻力（ＴＰＲ）、释氧量（ＤＯ２）、耗氧量（ＶＯ２）及氧摄取率（Ｏ２Ｅｘｔ）。结果显示，ＤＰＸ使ＣＯ、ＨＲ、ＬＶｄｐ／ｄｔｍａｘ呈剂量依赖性增加（Ｐ＜０．０１）和使ＴＰＲ下降（Ｐ＜０．０１），余无变化。在血液稀释后ＤＰＸ对以上各值改变不明显。在稀释前ＤＯＰ作用与ＤＰＸ相似，但大剂量可显著增加ＤＯ２和ＶＯ２（Ｐ＜０．０５），ＴＰＲ也上升至对照值水平。稀释后ＤＯＰ仍使以上各值增高（Ｐ＜０．０１），而ＤＯ２和ＶＯ２、Ｏ２Ｅｘｔ维持不变。ＤＯＢ的作用类似ＤＯＰ，但稀释后ＴＰＲ不升高，ＨＲ显著增快（Ｐ＜０．０?

Toevaluatetheefectsofdopexamin(DPX),dopamine(DOP)anddobutamine(DOB)onhemodynamicsbeforeandafterhemodilution,eighteenanesthetizeddogswererandomlydividedintothreegroups(n=6,eachgroup):DPX,DOPandDOB.Theinfuseddosesoftheabovethreedrugswere1,2and7μg·kg-1·min-1,respectively,andtheywereinfusedatintervalof15minbeforeandduringhemodilution,whichwasproducedbybloodwithdrawal(22ml/kg)andreplacementwithanequalvolumeof6%dextran.Ascendingaorticflow(CO)wasmeasuredbybloodelectromagneticflowprobe,andmeanaorticarterypressure(MAP),leftventricularend-diastolicpressure(LVEDP),LVdp/dtmax,strokevolume(SV),heartrate(HR),totalperipheralresistance(TPR),oxygendeliver(DO2),oxygenconsump-tion(VO2)andoxygenextract(O2Ext)weremeasuredorcalculated.Thehemodilutionresultedin50%decreasesinHctand50%increasesinCO,HR,SVandLVdp/dtmaxanddropsinTPR,DO2andVO2.Folowinghemodilution,increasesofCO,SVandLVdp/dtmax,AAP,DO2andVO2werenotre-mainedinDPXgroupanddidnotchangedinDOBgroup,buttheaboveparametersandTPRwerefur-therincreasedsignificantlyinDOPgroup.ItisconcludedthattheinotropicandchronotropicefectsofDPXwereinhibited,andtheefectsofDOBwerenotaffectedandtheefectsofDOPwereintensifiedfolowingacuteisovolemichemodilution.