文献翻译——呼吸酒精分析将标准化与水汽结合，就像血液酒精分析一样精确

第1页外文文献资料Breathalcoholanalysisincorporatingstandardizationtowatervapourisaspreciseasbloodalcoholanalysis1.IntroductionTheanalysisofalcoholinbloodandbreatharetwodifferentquantitativemethodstodetermineanindividualsdegreeofIntoxication.Bloodalcoholanalysishastraditionallybeenregardedasthegoldstandardmethod,butitisinvasive,expensiveandimpracticalcomparedwithbreathalcoholanalysis.Therefore,ontheassumptionthatthereliabilityofbreathanalysisissimilartothatofbloodanalysis,breathanalysiswouldbethepreferredmethodtouse.Indeed,manyjurisdictionsnowusebreathanalysisasastandalonetestfordrunkdrivingprosecution.However,studiesvalidatingtheprecisionofbreathalcoholanalysisagainstbloodalcoholanalysisarescarce1,2asarestudiesutilizingarterialbloodsamplesforcomparisonsofbloodandbreathalcoholconcentrations35.Sinceitisthealcoholcontentinarterial,asopposedtovenous,bloodthatreachesthebrainandaffectsthepersonsperformanceandbehave6,thearterialbloodalcoholconcentration(ABAC)representsthetoxicologicalmostrelevantquantitativemeasureofdrunkenness.Forbloodandbreathanalysistobeinterchangeablewitheachotherthereneedstobeastablerelationbetweenbloodalcoholconcentrations(BAC)andBrastallsamplingtimesafterdrinkingalcohol.However,theratioofBAC-valuestocoexistingBra-valuesisconsideredtobemorevariableduringabsorptionofalcoholfromthegutcomparedtothepost-absorptivestate6090minpost-dosing79.Oneconsequenceofthisisthatifasubjectistestedduringabsorptionofalcoholthereisariskofunequalpunishmentsdependingonwhichanalyticmethodthatwasemployed.2.SubjectsTwelvehealthyindividuals,sevenmalesandfivefemales,wereenrolledaspaidvolunteers.Agesrangedfrom18to57yearsandbodyweightsfrom62to102kg.Allsubjectsweremoderateconsumersofalcoholicbeverages.Allsubjects第2页weremoderateconsumersofalcoholicbeverages.ThestudywasapprovedbytheEthicsCommitteeofLuUniversity,Sweden.Allsubjectsgavetheirinformedconsent.ExperimentalprocedureTheexperimentsstartedeitherat09.00a.m.or01.00p.m.afteraminimumof2hourfastingafteralightmeal.Thecatheterwasconnectedtoabagofissalinecontaining0.5Eheparin.Thesalinebagwasexternallypresstoapproximately300mmHginordertocontinuouslyflushthearterialcatheterviaapressuretransducer.Twothree-waystopcocksinserieswerefittedbetweenthehosefromthesalinebagandthecatheter.Athintubewasthenswallowedandputinthestomachofeachsubject.Ourstudyprovided168duplicatearterialbloodsamplesand167duplicatebreathsamplesthatwereobtainedexactlysimultaneously.Thesampleswithineachpairofbloodandbreathsampleswereseparatedby243(meanSD)s.Oneduplicatebreathsamplewasdiscardedbecausethesubjectregurgitatedattheendofthealcoholinjectionandmouthalcoholcouldnotbeexcludedbythecomputersoftware.Thesamples(twobloodandtwobreath)wereobtainedattimedintervalsof2,5,10,15,30,45,60,75,83,91,99,105and135minaftertheendofthealcoholadministration.Eachsubjectwasthenaskedtoconsume20mlofundilutedgin(40%(v/v)asquicklyaspossiblewithoutrinsingthealcoholinthemouthbeforeswallowing.Onelastduplicatebreathandbloodsamplewasobtained30minafterthealcoholingestionbymouthtoensureabsenceofmouthalcohol,correspondingto167minafterthealcoholinjectionviathetubewascompleted.Duringthe8391minintervalthesubjectsmadesomeexhalationsfromdifferentdistancesandagainstdifferentpressures(datanotshown).TheBraweredeterminedwithaprototypeanalyzer(ServoAB,Sweden),constructedtoallowcontactfree(nomouthpiece)exhalations.Theknownalveolarwaterpourconcentrationat378C(43.95mg/L)11isusedbytheanalyzertocompensateforthedilutionofthebreathsamplebyambientair.Theinstrumentutilizesinfraredspecbythreedifferentwavelengthsforalcoholdiscriminationandquantification.ThreeadditionalwavelengthsareusedtodeterminetheCO2andwaterpourconcentrationsandserveasareference.Thealtogethersixbandfiltersaremountedonadisc,rotatingatrateof33Hz.Thealcohol-,CO2-andwaterpourconcentrationsarethusdetermined33timesper.第3页AriseintheCO2concentrationtoapresetlevelidentifiesadeliveredbreathsampleandtriggersthestartofameasurement.AdecreaseintheCO2concentrationtoapresetleveldenotestheendofthesample.Alldatapointsobtainedfrom2sbeforethetimeofthetriggeruntil3saftertheendwillbeincludedintheactualbreathsamplebythecomputersoftware.Thealcoholconcentrationsfromthebreathsamplearesubsequentlyplottedasafunctionofthesimultaneouslydeterminedwaterconcentrations.Thesoftwarethenfitsabeststraightlineinthescatterplotofalcoholandwaterconcentrationsbytheleastsquaremethod.Thestraightline,whichstartsatthepositionoftheambientwaterconcentrationandambientalcoholconcentration(zero),isextendedtotheknownalveolarwaterconcentrationat378C(43.95mg/L).ThealcoholconcentrationthatcorrespondstothiswaterconcentrationisreportedastheactualBraofthebreathsample.3.ResultsTheprecisionofbreathalcoholanalysiswasasgoodastheprecisionofbloodalcoholanalysis(CV2.40%vs.2.38%;p=0.43)(Table1).A95%confidenceintervalforthedifferencebetweentheCV-valueswasto0.33%.Therewasonlyasmallvariationbetweenthefirstandthesecondoftheduplicatedeterminationsasindicatedbytheminimalmeandifferencebetweenthebloodalcoholdeterminations(0.0028mg/g;95%CIto0.0002mg/g)andthebreathalcoholdeterminations(0.00045mg/L;95%CIto0.00196mg/L)(Table1).AlltheindividualABAC/Braratiotimeprofilesshowedthesametendency,namelyagradualdecreasefrom2minpostdosinguntilastabilizationoccurred,around30minpostdosing,afterwhichtheratiowasstable(Fig.2).ThevariationoftheABAC/Braratiosbetweensubjectsalsoconsistentlydecreasedbetween2and30minpostdosingasindicatedbydecreasingCV-valuesforeachtimepoint(42%,17%,9.7%,6.2%and4.6%at2,5,10,15and30minpostdosing,respectively).From30to167minpostdosingthevariationoftheABAC/Bra第4页ratiosbetweensubjectsseemedtobestable(Fig.2)withameanCVof4.7%.TheABACtimeprofilesshowedgreatdifferencesbetweenindividualsubjects.AtthetimetheABAC/Braratioswerestabilized(30min)halfofthesubjectswerestillintheabsorptivestate(Fig.2).TheABAC/Braratiosimmediatelypriortothealcoholingestionof20mlgin(135min)werenotstatisticallydifferentfromtheratiosat167min(2088130vs.207976;p=0.95).4.DiscussionThemainfindingofthisstudyisthatbreathalcoholanalysisbasedonstandardizationofbreathalcoholtowaterhasequallygoodprecisionasthedeterminationofbloodalcoholatanaccreditedforensiclaboratory.Thiscontraststopreviousstudiesshowingbetterprecisionofbloodthanbreathalcoholanalysis1,2.TheprecisionofduplicateBra-determinationsinthosestudiesweresomewhatworse(3.774.8%)comparedtothepresentstudy(2.40%).Althoughitisdifficulttocomparetheresultsofdifferentstudiessincetheprotocolsofthestudiesmaydiffersignificantly,itispossiblethatthebetterprecisioninthisstudyinpartmaybeexplainedbythemethodologyutilizedbytheanalyzer.Bystandardizingthealcoholconcentrationtofullysaturatedwaterconcentrationat378C(43.95mg/L),theinfluencefromvariationsinbreathtemperatureandexhaledvolumeisreduced1315.Theprecisionoftheanalyzerusedherewassomewhatbetter(1.7%)inapreviousstudy3.Thisispossiblyexplainedbydifferencesinthedesignofthestudyprotocols.Theprotocolinthepresentstudyprescribedarelativeabundanceofmeasurementsintheearlyabsorptionphase,inwhichthevariabilitycouldbeassumedtobeparticularlyhigh.Infact,limitingthecalculationoftheprecisionofduplicatebreathmeasurementsmadebetween30and167minpostdosingwouldyieldaCVof1.76%inthisstudy.Theagreementbetweenthefirstandseconddeterminationofduplicatebloodandbreathsampleswereverygoodshowingameandifferenceofonlymg/gand0.00045mg/L,respectively(Table1).The95%CIofthemeandifferencesincludedzeroforbothbloodandbreathanalyses,suggestingnosignificantsystematicerrorbetweenthefirstandseconddetermination第5页(Table1).BloodandbreathasdifferentspecimensforalcoholanalyseswerecomparedbyBlandAltmanplots(Fig.1).Thesedisplayedasimilarmeandifferenceand%LOAforduplicatebloodandbreathdeterminations,indicatingasimilarprecisionofbothmethodsforalcoholquantification.Inaddition,thestudyshowsthatfrom30minandonwardsaftertheintakeofanalcoholbolusastableABAC/Braratioispresent,enablingareliablepredictionoftheABACfromaBra.Duringthefirst15minpostdosingtheBratendedtounderestimatethecoexistingABACwithahighlyvariableABAC/Braratio.Thisisinkeepingwiththeresultsfrompreviousstudiesusingarterialbloodsamples3,4butinstarkcontrasttostudiessamplingvenousbloodwheretheratiorisescontinuouslypostalcoholdosingandastablerelationbetweenbloodandbreathneverisestablished3,4,9,17.Althoughitmaybearguedthatarterialbloodsamplingisnotasreadilyavailableasvenoussampling,itisscientificallymorerelevanttoevaluatebreathsamplesagainstarterialbloodsincetheABACisthecauseofthetoxiceffectsofalcohol6.ThelargevariationofearlyABAC/Braratiosbetweenthesubjectsislikelyexplainedbythefactthateventinyabsolutechangestoasmalldenominator,inthiscasetheBra,causelargechangestoacalculatedratio18,19.TherewasacleartendencyfortheBra-valuesbetween2and15minpostdosingtounderestimatethecoexistingABACcomparedtotheBra-valuesbetween30and167min.Thiscanbeexplainedbyanexchangebetweenbreathalcoholandtheairwayduringexhalation20,21.Assumingthattheairwayintheearlyabsorptionphaseisrelativelydevoidofalcohol,completionofalcoholbetweeninhaledairandbloodwilltakeplaceinthe.Subsequently,thealveolarairwilldepositsomeoftherelativebreathalcoholsurplustotheairwayduringexhalation.However,asthealcoholconcentrationwillriseduetothedistributionofalcoholfromthebronchialarterialblood,lessalcoholinbreathairwillbedepositedtotheairwayduringexhalationandtheBrawillincreaseinrelationtothecoexistingABAC.ItneedstobestressedthatanongoingabsorptionofalcoholfromthegutdoesnotexcludethepresenceofastableABAC/Braratio.AtthetimeofstabilizationoftheABAC/Braratio(30min)halfoftheABACtimeprofileswerestillrising.Thus,astablerelationshipbetweenABACandBradoesnotseemtobedependent第6页onthatapost-absorptivestatehasbeenreached,whichhasbeenproposedasanecessaryprerequisiteforasafeuseofbreathtesting7.Thisisfurthersupportedbythefactthatanadditionalintakeof20mlgin(6.3galcohol)inalreadyintoxicatedsubjectsdidnotsignificantlyaltertheABAC/Braratio30minlater.ThekineticconditionofastableABAC/Braratiomaynotberelatedprimarilytotheattainmentofastatebutinsteadtotheofasignificantconcentrationgradientofalcoholbetweenarterialbloodandairway.ItisacknowledgedthatthestudyingoftheABAC/Braratioduringthefirst30minafteralcoholintakemostlyisoftheoreticalinterest.Becauseoftherequestforawaitingperiodtoruleoutmouthalcoholandotherpracticalreasons,anevidentbreathtestisunlikelytobeundertakenbeforeastablerelationbetweenBraandABACisestablished.Shoulditoccurthough,itwouldworkinoftheallegedoffender.Whilethishypotheticallycouldfreetheguilty,moreimportantlyitcreatesasafeguardagainstwrongfulconviction.4.MaterialsandmethodsDuringathreemonthperiod(1stSeptember30thNovember2011)positiveroadsidebreath-alcoholtestsweremadein1900motoristsfromwhomasampleofvenousbloodwasalsotakenandanalyzedbygas.Beforeanalyzingthedata,caseswithbothBACandBrabelowtheanalyticcut-offof0.10g/kg(N=25)wereexcluded.Thesecasesoftenrepresenteddriverswhowereimpairedbydrugsotherthanalcoholandnotcaseswherethepolicesuspecteddrivingundertheinfluenceofalcohol.Themean(median)andlongesttimebetweentheroadsidebreath-alcoholtestandthesamplingofvenousbloodwas0.71h(0.58h)and6.08h,respectively.Becauseoftheunavoidabletimedelaybetweenmakingtheroadsidebreathalcoholtestandsamplingblood,theresultswereadjustedfortheamountofalcohollostthroughmetabolism.ThisadjustmentassumesallsuspectsareinthepostabsorptivephaseoftheBACcurve,althoughweareawarethatthismightnotbethecase.Inthecalculationsbothlowandhighratesofalcoholeliminationfrombloodof0.10g/kg/hand0.25g/kg/h,respectivelywereused15.Thisrangeofeliminationratesshouldapplytothevastmajorityofpeopleprovidedtheyhaveenteredthedecliningphaseoftheblood-alcoholcurvewhentested.Thepoliceuseroadsidebreath-alcoholtestsinconnectionwithroutinecontrolofdriversobriety,afteramovingtrafficofforwhenaroad-trafficcrashisinvestigated.Thevarious第7页typesofhand-heldinstrumentscurrentlyusedbytheFinnishpoliceincorporatechemical(fuelcell)oxidationtodeterminetheconcentrationofethanolinbreathandareprovidedbyseveralmanufacturers;AlcolmeterS-D2andLionAlcolmeter500(LionLaboratories,UK),Alcotest(Drager,Germany)andAlcoSensor(IntoximetersInc.,USA)14.Mostoftheinstruments(88%ofthetests)wereAlcolmeterS-D2andthesearepre-calibrated(BBR2260:1)togiveanestimateofthepersonsBAC.ThenewerinstrumentsreportresultsasBra(mg/L),whichwasconvertedintoBACusingthesameBBRof2260:1.Venousbloodsamplesfromapprehendeddriverswerecollectedbyaphysicianorphlebotomistinevacuatedplastictubes(10ml)thatcontainedamixtureofsodiumfluorideandpotassiumoxalateaspreservativeandanticoagulant.VenousBACwasdeterminedinduplicatebyheadspacegaschromatographyandflameionizationdetector.Forthepresentstudy,themeanBACwasreportedwithoutmakinganydeductionforanalyticuncertainty16.Duringthisstudy,anopportunityarosetoestimatetherateofalcoholeliminationfrombloodbasedontwoconsecutivebloodsamplestaken24hapart.ThechangeinBACovertimeintervalbetweensamplingwasusedtoestimatetheeliminationrateofalcoholfromblood.Thesecondsamplewastakenbecausesomesuspectsclaimedortherewasreasontobelievetheywouldclaimconsumptionofalcoholafterdriving,so-calleddrinking-aftertheoffence.BecauseBACisgenerallyconsideredthegoldstandardandreferencemethodinconnectionwithforensicalcoholtesting,thiswasusedastheindependent(xvariable)inalinearregressionanalysis.Thebreath-alcoholscreeningtestsresultswereplottedasthedependenty-variable.Theleast-squaresregressionwasdoneontheresultsbeforeandaftermakingacorrectionforeliminationofalcoholfrombloodbetweenthetimesofsamplingbloodandbreath.Thiscalculationwasdoneusingaslow(0.10g/kg/h)andrapid(0.25g/kg/h)rateofethanoleliminationandnecessarilythisassumesthatallsuspectswereinthepost-absorptivephaseofthealcoholcurvewhenbreathtested.Roadsidebreath-alcoholtestsareusuallydonewiththedriversittingbehindthewheelofthevehicleandonlyasingleanalysisisthenorm.Noneofthehand-heldbreath-analyzersarefittedwithtechnologytodetectmouth-alcohol,suchasbymeansofaslopedetector18.Thelargenumberofdifferentbreathinstrumentsinuseanduncertaintyabout第8页calibrationproceduresandalsothefactbreathsamplingwasdonemanually,probablyexplainsthelargeresidualSDof0.40g/kg,whichisanindicationofrandomvariation.Forcomparison,theresidualSDwas0.15g/kgwhenanevidentialbreathanalyser(Intoxilyzer5000S)wasusedtotestdrunkendriversandwhenthecalibrationwascontrolledwitheverysubjecttest19.第9页中文翻译稿1.介绍血液和呼吸的酒精测试是两个不同的定量的方法来确定一个人的中毒程度。血液酒精测试历来是视为“金标准”的方法，但它与呼气酒精测试相比，是有侵入性的，昂贵的和不切实际的。因此，假设呼吸测试的可靠性与血液测试是相似的，呼吸测试将是优选的使用方法。事实上，许多司法管辖区现在使用呼吸测试作为一个独立的测试醉驾起诉。然而，研究证实精密的呼气酒精测试相对于血液酒精测试是比较稀少的1,2因为是利用动脉血样品研究比较血液和呼气酒精浓度3-5。因为它是在动脉中的酒精含量，如反对静脉，血液到达脑部，并影响人的性能和行为6，动脉血酒精浓度（ABAC）代表毒理学最相关的定量醉酒测量。对于血液和呼吸测量是可以相互转换的，但需要饮用酒精后在血液酒精浓度（BAC）和布拉奇失速采样时间之间有一个稳定的关系。然而，BAC值和BRAC值的比值在吸收酒精的过程中被认为是更有价值的，相比于药后肠道吸收后状态60-90分钟7-9。这样做的一个后果是，受试者在测试酒精的吸收的过程中存在一个不平等处罚的风险，取决于采用哪个测量方法。2.测试人员12名健康人，7男5女，被纳入支付志愿者。年龄从18到57岁，体重从62到102公斤不等。所有受试者适度的饮用酒精饮料。这项研究由瑞典隆德大学的伦理委员会批准。所有受试者会给他们知情同意书。实验开始是在上午九时或下午1时,餐后至少禁食2小时。将导管连接到一个袋含有0.5肝素/毫升等渗盐水。盐水袋外部加压到约300mmHg，以便通过压力换能器，以连续地冲洗动脉导管。两个三通旋塞串联拟合从盐水袋软管和动脉导管之间。一根细管，然后咽下去，摆在每个主题的胃。我们的研究提供了168重复动脉的血液样本和167重复被同时精确地获得呼气样本。内的样本每对血液和呼气样本都是由24分开？3（意思？SD）秒。一重复呼吸样品被丢弃，因为受试者在反刍的端醇注射口醇不能排除由计算机软件。样品（2血液和两个呼吸）分别以一定的时间间隔得到的醇结束后2，5，10，15，30，45，60，75，83，91，99，105和135分钟管理。每个受试者又问消耗20毫升稀释杜松子酒（40（V/V），尽可能快地未经漂洗醇在口腔中之前吞咽。得到最后一个重复的呼吸和血液试样30分钟后的酒精摄入口，以确保没有嘴的酒精，相当于酒精注射液通过胃管后167分钟完成。在83-91分钟-区间的主题作了不同距离的一些呼气和针对不同的压第10页力（数据未示出）。该Bra确定与原型分析仪（AB，瑞典），构造允许自由接触（无口片）呼气。已知的肺泡水蒸汽浓度在37（43.95mg/L）的11所使用的分析仪补偿所述呼吸试样的稀释由环境空气中。该仪器由三个不同的波长为酒精判别利用红外光谱和定量。三个附加的波长来确定的二氧化碳和水蒸汽的浓度，并作为一个参考。在总共6过滤器被安装在盘上，旋转以33Hz的频率。在酒精，CO2-和水蒸气浓度从而确定每个第33次。上升在theCO2集中到预设级别标识递送呼吸样品，并触发一个测量开始。一减少在CO2浓度为预设电平表示样品的末端。所有结束后，从2秒获得的数据点触发的时间点前3秒会被包括在计算机软件的实际呼吸试样中。酒精从呼气样品浓度随后绘制成的一个功能同时测定水蒸汽的浓度。然后，该软件适合一个“在酒精和水蒸汽浓度的散点图”最佳直线最少。的直线，其开始于在环境中的位置水蒸气浓度和环境酒精浓度（零），延伸到已知的肺泡水蒸汽浓度在37（43.95mg/L）。酒精对应于这种水蒸汽浓度的浓度被报告为呼气样本的实际BRAC。3.结果呼吸酒精含量分析的精度是不如精密的血液酒精含量分析（CV2.40和2.38，P=0.43）（表1）。对于之间的差别A95置信区间CV值是？0.38至0.33。有在第一和之间只有小的变化重复测定的第二如由表示血液中的酒精测定之间的最小平均差（？0.0028毫克/克;95CI为0.0057至0.0002毫克/克）并在呼气酒精测定（0.00045毫克/升;95CI0.00106什么？0.00196毫克/升）所有的个体ABAC/布拉奇比-时间曲线显示相同的趋势，从2分钟后给药，即逐渐减少直到一个稳定的发生，约30分钟后加药，后该比率是稳定的。在ABAC/BRAC的变化学科之间的比率也持续2之间下降通过为每个减小CV值所指示的30分钟给药后时间点（42，17，9.7，6.2和24.6，5，10，15和30分钟给药后，分别）。从30到167分钟后加药的ABAC的变化/主体之间BRAC比率似乎稳定（图2）为4.7，平均CV。在ABAC-时间曲线之间表现出很大的差异个别科目。当时的ABAC/BRAC率分别为受试者的稳定（30分钟）的一半人还在吸收状态。在ABAC/布拉奇比紧接酒精的20毫升杜松子酒（135分钟）摄入均无统计学差异从167分。这项研究的主要发现是，呼吸酒精含量分析基于呼气酒精标准化水蒸气具有同样出色的精度为血液酒精以确定认可的法医实验室。与此相反，以先前的研究显示出较好的血液精度比呼吸酒精含量分析1,2。重复BRAC-测定的那些精度研究是稍差（3.77-4.8），相比于本研究（2.40）。虽然很难比较由第11页于研究的协议，不同的研究结果可能显著不同，它有可能在该较好的精度研究中的部分可以通过由所利用的方法进行说明分析仪。通过标准化的酒精浓度，充分饱和水蒸汽浓度在37（43.95毫克/升），在从变化呼吸的温度和呼出的影响体积减小13-15。该分析仪这里使用的精度是有所好转（1.7），在先前的研究中3。这可能是由解释差异的研究方案的设计。在该协议本研究中规定的测量相对丰富初期吸收阶段，其中，所述可变性可能是假定为特别高。实际上，限制的计算重复呼吸测量30之间所做的精度和167分钟给药后会产生1.76简历这项研究。在第一和第二测定之间的协议重复的血液和呼吸样品很好呈现出分别指的仅0.0028？毫克/克和0.00045毫克/升，差（表1）。的平均差异的95CI包括零为血液和呼吸分析，提示找不到显著在第一和第二判定之间的系统误差（表1）。血液和呼吸，不同的标本进行酒精分析由布兰德-Altman图（图1）进行了比较。这些显示了类似的平均差和LOA重复的血液和呼吸测定，说明两者的相似精度方法酒精定量分析。此外，研究表明，从30分钟，并起酒精的摄入量后，弹丸稳定ABAC/布拉奇比目前，从BRAC使ABAC的可靠预测。在第一个15分钟后加药布拉奇往往低估共存的ABAC有高度可变ABAC/BRAC比例。这是符合从先前的研究结果，采用动脉血液样本3,4，但形成鲜明对比的研究采样静脉血，其中的比例持续上升后酒精的剂量和血液和呼吸之间的关系稳定从来没有成立3,4,9,17。虽然它可能会争辩说，动脉血采样并不如容易作为静脉采样，这在科学上是更相关的评估呼吸对自ABAC动脉血液样本是的原因醇的毒性作用6。之间的早期ABAC/布拉奇比率大的变化主题很可能是由事实解释说，即使是微小的绝对变为一个小分母，在这种情况下，BRAC，造成大改变为计算出的比率18,19。有2之间的BRAC-值明显的趋势15分钟后加药低估并存ABAC相比于30和167分钟之间的BRAC值。这可以经呼气