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Thephysiologicparadigmthatcliniciansreferenceintheirattemptstoexplainandunderstandthebiologyofbothhealthyandcriticallyil

lpatientshasbeeninevolutionformorethan100years.（临床医师尝试着阐述和了解健康和危重症患者而借助的生理学范式已经发展100多年了。）Interestingly,ourunderstandingoftheclinicalcirculat

ionhasalwaysbeenthoughtofas‘complete’,（有趣的是，人们对临床循环的理解一直被视为“很完整”，）withcreativecliniciansinvokingavarietyofreason

stoexplainawayapparentdiscrepanciesbetweencommonlyusedmentalmodelsandtherealitiesofclinicalmedicine.（而富有创新性的临床医师

则希望通过种种解释消除常用思维模式和临床医学现实之间显著的差异。）Themostprimitiveformulationofthecirculationentailssimpleconservationofmatter:（最原始的循环公式蕴含着简单的物质守恒：）CardiacOutpu

t=StrokeVolumexHeartRate=Qt=SVxHR（心输出量（CO）=每博量×心率=Qt=SV×HR）Thisstatement,whileobviouslyalwaystrue,offerssapientpract

itionerslittleinsightintowhythecirculationinaarticularpatientmightbeunacceptable,andhowtheymightrationallyinterven

e.（很显然，该表述很正确，却几乎没有为智慧的工作者深入了解为何个别患者的循环可能不稳定以及如何进行合理的干预提供帮助。）Duringthemid-20thcentury,arelativelycompleteparadigmforunder

standingtheroleoftheenousreturnincontrollingthecardiacoutputwasrefinedbyGuytonandhisco-workers,andhasbeenrepet

itivelyvalidatedsinceitwasfirstdescribed(refsJacobsohn,Magder,Guyton,Sylvester).在20世纪中叶，Guyton及其同事修订了一个相对完善、关于了解静脉回心血量在控制心输出量中的作用的范式，该范式从首次被描述就进

行了反复验证。Althoughnotcomplete,thistheorywaspowerfulinthehandsofthosewhounderstoodit.尽管该理论还不完善，却对已理解该理论的人群产生了

很大的作用。Theballoon-tipped,flowdirected,thermistorequippedpulmonaryarterycatheterheraldedthesubsequenteraoftheunderstandingofthe

clinicalcirculation.装备有末端套囊、血流导向以及热敏电阻的肺动脉导管，预示着理解临床循环时代的到来。Thisdevice,coupledwithadeepunderstandingofthemechanicsofleftventricularf

unctionheraldedtheerainwhichthecirculationandallofitspathologywereunderstoodfromtheperspectiveofthele

ft-ventricle–whichsomenowrefertoastheLVcenteredviewofthecirculation(Sagawa).对肺动脉导管及左心室力学功能的深入了解预示着从左心室的视角来理解循环以及循环病理学时代的来临。Forthose

whotrainedinthatparadigm,preload,afterload,andcontractilitywerethedeterminantsofcardiacoutput:接受该范式培训的

人群应该了解，前负荷、后负荷以及收缩力都是心输出量的决定因素：CardiacOutput=CO=MAP-RAPSVR(WhereMAP=MeanArterialPressure,RAP=RightAtrialPressureandSVR=Systemi

cVascularResistance)（MAP=平均动脉压，RAP=右心房压，SVR=体循环阻力）Somepatientshavearightheartlimitedcirculation,whichcanbef

ormulatedusingaverysimilarequation:有些患者存在右心循环受限，可以用一相似的方程式计算心输出量：__CO=PA-LAP__PVR(WherePA=MeanPulmonaryArteryPressure,LA

P=LeftAtrialPressure,andPVR=PulmonaryVascularResistance).（PA=平均肺动脉压，LAP=左心房压，PVR=肺血管阻力）。Nevertheless,theLVcenteredviewofth

ecirculationfocusedonpreload,afterload,andcontractility,andwasfrustratedbyavarietyofobstacles.然而，以左室为中心观察循环主要以前负荷、后负荷和收缩力为主要研究对象，但若遇到一些障碍，

则结果就相形见绌了。Themostimportantwasthepoorcorrelationbetweenmeasuredfillingpressuresandleftventricularend-diastolicvol

umesasassessedbyechocardiography(refsKumar,Hofer,Kramer).最重要的是，通过超声心动图进行评估发现，充盈压和左心室舒张末容积之间的相关性较差。Ech

ocardiographyhasdocumentedthatLVcomplianceisfarmoredynamicthananyonebelievedpriortoitswidespreadclinicaluse(Coriat).通过超声心动图

证实，左心室顺应性比之前认为已广泛应用于临床的任一参数更优越。Theother,moreinsidiousproblemwiththeLVcenteredworld-viewisthatadherentstendtoregardRAPal

mostexclusivelyasanindexofcirculatoryvolume,forgettingthatitisthedownstreamhydrostaticresistancetovenousreturninthemodelofGuyton:另一方面，

以左心室为中心观察循环存在的潜在问题为，支持者更趋向于认为，RAP几乎为循环容量唯一的指标，而遗忘了在Guyton模型中，RAP为下游流体静力学阻力：VR=CO=Pms–RAPRVR(WhereVR=VenousRet

urn,RAP=RightAtrialPressure,andRVR=ResistancetoVenousReturn)（VR=静脉回心血量，RAP=右心房压，RVR=静脉回心阻力）Thecirculationinanypatientatanymomen

tintimeistheproductoftheinteractionofthevenouscircuitwiththeheart(thepump).TheRAPisaproductofthatinteraction

.对于任一患者的任一时刻，循环都是心脏（泵）和静脉回路相互作用的产物。RAP即为该相互作用的产物。Allofthishasproducedthepresentunderstandingofclinicalhemodynamics,whichispredicate

donasynthesisofvenousreturnandcardiacphysiology(Sylvester,Jacobsohn).当前对临床血流动力学的理解综合了静脉回心量和心脏生理学。Thismodelcanbeusedtogene

rateaseriesofquestionsthatcanguidetheassessmentofapatientinshock.该模型可以解释一系列问题以指导休克患者的评估。WhatisShock？Shockisglo

ballyinadequateperfusionoftissuessufficienttoproducebothtissuehypoxiaandorgandysfunction.休克为全身组织灌注不足导致组织缺氧和器官功能失调。W

hileshockisclassicallyassociatedwithhypotension,thereisincreasingacceptanceofthecontentionthathypotensionisarelatively‘late’indicatorofs

hock,andthatcliniciansshouldbemoreattunedtoorgansystemdysfunctionasevidenceofshock.虽然休克通常与低血压有关，然而有越来越多的观点认为，低血压已是休克相对“晚期”的指标，临床医师更应习惯于以器官系统功能失调

作为休克的证据（表1）。SignsofShock:-alteredmentation-oliguria-decreasedmixedvenousorcentralvenoussaturation-hypotension,abnormalheartrate-lacticacidosi

s-peripheralcyanosis(variable)Inboththecriticalcareandtraumaliterature,theendpointsforresuscitationhavealsoevolved.Whiletradition

alendpointssuchasmeanarterialpressureandcentralvenouspressurearestillregardedasimportant,increasinge

mphasisisbeingplacedonthemixed/centralvenousoxygensaturation(Ladakis)andlactatelevelsintheblood.在重症监护和创伤医学文献

中，复苏终点也已不断演变。虽然传统的复苏终点（如，平均动脉压和中心静脉压）仍然很重要，但越来越强调混合/中心静脉氧饱和度和血乳酸水平。Thecombinationofinexpensiveandrea

dilyavailableserumlactatesandincreasingappreciationoftheprevalenceofhyperchloremicacidosisinthesettingoflargevolumeresuscitationhasledtoth

enearabandonmentofthebaseexcess/deficitasaguidetotheadequacyofresuscitation.在大容量复苏的过程中，作为复苏适度的风向标，方便快捷的血清乳酸测定结合日益受宠的高氯血症酸中毒已经逐渐取代碱过量/缺失。Se

veralpublicationsoverthepastseveralyearshavedampenedenthusiasmfortheuseofcentralvenousoxygenation(Chawla,Sander,Varpula),butitneverthelessremainsav

eryusefulindicatoroftheadequacyofoxygendelivery.在过去数年中，许多论文已经降低了对使用中心静脉氧饱和度的热情，但对于氧供充足与否而言，其仍然为非常有用的指标之一。Itishelpfultounderstandthemoder

nincarnationoftheFickEquationoftherelationshipbetweenoxygenconsumption,cardiacoutput,arterialoxygencontent,andmixedvenousoxygencontent.

这有助于理解Fick方程的现代演变，即有关氧耗量、心输出量、动脉血氧含量以及混合静脉氧含量之间的关系。Thisalgebraicrearrangementemphasizesthatthemixedvenoussaturationisadequateonlywhenthede

liveryofoxygentotheperipheraltissuesiswellmatchedtotheirneeds:这种代数重组过程强调，只有当输送到外周组织的氧与外周组织的氧耗契合良好时，混合血氧饱和度才充足：SvO2(CvO2)=CaO2–VO2Qt(WhereSvO2is

themixedvenousoxygensaturation,CvO2isthemixedvenousoxygencontent,CaO2isthearterialoxygencontent,VO2istheoxy

genconsumption,andQtisthecardiacoutput)(SvO2为混合静脉氧饱和度，CvO2为混合静脉氧含量，CaO2为混合静脉氧含量，VO2为氧耗，Qt为心输出量）Importantly,asoxygendeliveryt

othetissuesfalls,oxygenextractionrises,andcontinuesuntilthetissuesarenolongerabletoextractmoreoxygen.Whenthishappens,crisisensue

s.重要的是，当组织氧供下降时，氧解离增加，直至组织再没有能力摄取更多的氧。当发生这种情况时，危机就随之而来。Intheleftfigure,oxygenextractionincreasesasoxygendeliveryde

creases.Whenthetissuesreachthelimitsoftheirabilitytoextractoxygen(thecriticalextractionratioERc),thecriticaloxygendelivery

hasbeenreached(Qo2c),andfurtherdecreasesinoxygendeliverywillbeassociatedwithadeclineinoxygenconsumption.Arterialhypoxemia,anemia,hyper-metabolis

m,andalowcardiacoutputalllowerthemixedvenousandcentralvenoussaturation.动脉低氧血症、贫血、高代谢以及低心排都可降低混合静脉和中心静脉氧饱和度。Increasi

ngly,practitionersareutilizingprotocolswhichincludeasoneoftheirendpointsacentralvenousoxygensaturationaboveacertainlevel(Ladak

is,Rivers).越来越多的临床医师开始参照指南，包括将一定水平的中心静脉氧饱和度作为复苏终点之一。Thisstrategyof‘forwarddefense’isinpartbasedontheincreasingrecognition

thathypotensionisarelativelylateindicatorofshock,andthatresuscitatingapatienttoamarginalbloodpressuremayleavethemw

ithaninadequatephysiologicreserve.这一“早期防御”策略部分基于将低血压视为休克相对晚期的指标的认同感增加，而且复苏患者达到临界血压，其可能处于不适当的生理储备。FromPhysics:V=IxRSubstit

utingproduces:BP–Pra=QtxSVR物理学：V=I×R替代公式：BP–Pra=Qt×SVR•Hypoperfusion(shock)canarisefrom:•-lowcardiacoutpu

t-lowSVR-thecombinationofalowcardiacoutputandhighSVR灌注不足（休克）可由以下因素引起：●低心排●低SVR●低排高阻（低心排和高体循环阻力）Asdemonstratedbytheabovefigure,wecans

uperimposetheStarlingcurvefromaboveleftuponthevenousreturncurvefromtheaboverightandgenerateagraphicalrepresentationofthestateofthecir

culation.ThecardiacoutputisrepresentedbytheYprojectionoftheintersectionofthesecurves,andtheCVPwemeasureclinically

isrepresentedbytheXprojectionoftheintersectionofthesecurves.将左侧的Starling曲线图和静脉回心血量图叠加，生成循环状态的图示。心排出量则是通过这些曲线的交叉点Y轴的投影表示的，临床监测的CVP通过曲线交叉点的X轴投影表示的。Dias

tolicdysfunctionisagenerallyunderappreciatedandveryimportantcontributororcauseofshockstates.舒张功能不全为一项被普遍低估、却非常重要的休克状态的诱因或病因。Inanimalmodelsofhemorrhag

icshock,evensmallreductionsinpleuralpressuresfromreducedlevelsofPEEPorreducedrespiratoryratescanproducedramaticimprovementsinsurvival(Herff).在失

血性休克动物模型中，即使由PEEP水平降低或呼吸频率减少导致胸腔压力细微的下降都可使动物模型的存活状况显著改善（Herff）。Thisdata,coupledwithsimilardatafromanimalmodelsofCPR,aregeneratingincreasedinterestin

ventilationstrategiesassociatedwiththelowestpossibleairwaypressuresinpatientswithshock.基于该数据及从心肺脑复苏动物模型中得到的相似数据，人们越来越对以尽可能最小的气道压力对休克患者进行通气的模式

感兴趣。BedsideAssessmentofthepatientwithshock休克患者的床旁评估Thefollowingquestionsconstituteanorderlywaytoassessthepatientwithinadeq

uatecirculation:1.IstheCardiacOutputReduced?2.Istheheart“toofull”?3.Whatdoesn’tfit?以下几个问题形成了一个有序的方法，可用于循环容量不足患者的评估：●心输出量是否减少●心脏是否“

太满”●什么方法不适合Isthecardiacoutputreduced?No→VasodilatedShockYes→Hypovolemicshock,CardiogenicShock,orObstructiontoVenousReturn心输出量是否减少不是→血管扩张性休克（

血流分布性休克）是的→低血容量性休克、心源性休克、静脉回心受阻Theabovefiguredemonstratesthesentinelfeatureofvasodilatedorhighcardiacoutputshock:thewidepulsepressure.血管

扩张性或高心排性休克的标志性特征为：脉压差大。Patientswithvasodilatedshockalmostinvariablyhaveapulsepressurewhichisgreaterthanhalfoftheirsystolicpressure,whereaspatientswi

thlowcardiacoutputshocktypicallyhaveapulsepressurewhichissubstantiallylowerthannormal.对于血管扩张性休克患者，脉搏压力大于收缩压的一半的状态几乎始终存在，总体而言，低心排性休克患者的脉压则低

于正常人。Apatientwithabloodpressureof80/30almostcertainlyhasvasodilatedshock,whereasapatientwithabloodpressureof80/60willhaveon

eofthecausesoflowcardiacoutput.当患者血压为80/30mmHg时，几乎可以确定存在血管扩张性休克，而血压为80/60mmHg时，则为引起低心输出量的原因之一Onexamination,patientswithvasodilatedshockwillhavebrisk

capillaryrefillwhilepatientswithlowcardiacoutputshockwillhavedelayedcapillaryrefill.通过检查可以发现，血管扩张性休克患者会出现快速的毛细血管再充盈，而低心输出量性休克患者则出现毛细血管再灌注延迟。运

用脉压差区分是血管扩张性休克和低心输出性休克DifferentialDiagnosisofVasodilatedShock:-Sepsis,Sepsis,Sepsis-SystemicInflammatoryResponseSyndrome(SIRS)(e.g.pan

creatitis)-Hepaticfailure-Anaphylaxis-Adrenalinsufficiency-AVfistula-Others血管性休克的鉴别诊断：-脓毒血症，败血症，菌血症-全身炎症反应综合征

SIRS（如胰腺炎）-肝衰竭-过敏反应-肾上腺功能不全-动静脉血管瘘-其他Isthehearttoofull?Ifthecardiacoutputislow,thedifferentiationofhypovolemicandcardiogenics

hockisaccomplishedthroughthereviewofpertinenthistorical,physicalexamination,andlaboratorydata.Histor

icalinformationisoftencompellinginitssupportfortheconclusionthathypovolemiaisthecauseofanunacceptablecirculation.如果合并低心输出量，低血容量性休克和心源性

休克的鉴别可通过相关病史的回顾、体格检查和实验室检查来实现。既往信息常常在得出低血容量为导致循环不稳定的原因这一结论时才引起人们的注意。CausesofHypovolemia:-Hemorrhage-insensiblelosses-redistributiontoextravascularsp

ace-GIlosses-renallosses-vasodilation(venodilation)引起低血容量休克的原因：-出血-意识丧失-血管外腔再分布-血糖指数下降-肾损伤-血管损伤SupportiveofCardiogenicShock:-jugularvenous

distention-extraheartsounds-pulmonaryedemainassociationwithnarrowPP-signsorsymptomsofmyocardialischemia-newheartmurmurs-cardiomyopathyormy

ocarditis心源性休克的支持依据：-颈静脉怒张-额外心音-和窄脉压有关的肺水肿-心肌缺血的标志和症状-新的心脏杂音-心肌梗死和心肌炎Cardiogenicshockismostreadilyassessedwithechocardiography.

ThedifferentialdiagnosisofcardiogenicshockincludesacuteLVinfarction,acuteonchronicLVfailure,RVinfarction,RVfai

lurefromsomecauseofincreasedpulmonaryvascularresistance,andpreviouslyundiagnosedvalvularlesionssuchasaorticsten

osis,mitralstenosis,andmitralregurgitation.通过超声心动图最容易对心源性休克进行评估。心源性休克的鉴别诊断包括急性左心梗死、慢性左心衰急性期、右心梗死、由某些因素造成肺血管阻力增加导致的右心衰以及先前未确诊的瓣膜疾病，如主动脉

瓣狭窄、二尖瓣狭窄和二尖瓣关闭不全。EchocardiographyhassupplantedtheSwan-Ganzcatheterasthemethodofchoiceforassessingth

epatientwithsuspectedcardiogenicshock.超声心动图已经取代Swan-Ganz导管成为评估疑似心源性休克患者的首选。Reasonsforthisincludeincreasingrecognitionthatpractitionerun

derstandingofhowtoutilizedatafromaSwan-Ganzcatheterisgenerallypoor(Iberti),difficultydemonstratingthatthesecathetersimproveoutcomes(Sandha

m),andincreasingacceptancethatcentralvenousgasescorrelatewellwithmixedvenousgases.其原因包括进一步认识到医师对如何应用Swan-Ganz导管知识的贫乏

，导管难以改善预后的阐释以及对中心静脉气体与混合静脉气体之间的良好的相关性的认同性增加。Perhapsmostimportantly,echocardiographicstudieshavedocumentedsu

rprisinglypoorcorrelationbetweenfillingpressuresasmeasuredbyinvasivemonitorsandleftventricularend-diastolicvolume(O

sman).Evidenceimpeachingtheuseofcentralvenouspressuremeasurementscontinuestoaccumulate,andisnowbeingsummarizedincolorfulreviewarticl

es(Marik).可能更重要的是，超声心动图研究已经证明，行有创监测获得的充盈压与左心室舒张末容积之间的相关性极差。关于中心静脉压监测的质疑证据也不断积累，并被总结成了丰富多彩的综述文章。Asaco

nsequenceoftheseinsights,expertsareincreasinglyadvocatingtheuseofarterialpulsepressurevariationasaguidetoadministeringfluid,wi

thadifferenceof>10-15%withrespirationstronglyassociatedwithafavorableresponsetofluidadministration(Michard,2005).鉴于以上观点，专家越来越主张将动脉脉压变异

度作为液体管理的一项指南，当呼吸相关性动脉脉搏压力变异度＞10%~15%时，液体治疗往往会产生比较好的反应。ThetwomostcommonlyusedmetricsareSystolicPressureVariation

(SPV)andDeltaPulsePressure(ΔPP).SystolicPressureVariationiseasiertoestimatefromconventionalmonitors,butisslightlyinferiortodeltaPulsePressure(als

oreferredtoasPulsePressureVariation–PPV).最常用的两种监测指标为收缩压变异度（SPV）和ΔPP。收缩压变异度更容易通过应用传统监护仪来评估，但略逊于ΔPP（也被称为，脉搏压力变异——PPV）。SPVand/orPPVoutperformbothCVPa

ndPcwpaspredictorsofvolumeresponsivenessinsepticpatientsandcardiacpatients,includingpatientsundergoingOPCABandpost-

opCABGs(Auler,Hofer,Kramer).对于败血症和心脏病患者，包括进行OPCAB以及CABG术后的患者，将SPV和/或PPV作为容量反应的预测指标优于CVP和PCWP。Newermonit

orsintendedforuseineithertheICUortheORincorporatesoftwarethatfacilitatestheevaluationoftheseparameters.通过应用ICU或OR中的较新的监护仪整合了便于分

析这些参数的软件。Othertechnologies,includingStrokeVolumeVariation(SVV)(Lahner,Machare-Delgado),andthePICCOderivedIntrathoracicBloodVolumeIndex(ITBV))

arebeingexploredasalternativestotheCVPinpredictingvolumeresponsiveness(Muller),butdonotyetmatchtheperformanceofeitherPPVorSPV.Thereisagrowingli

teratureregardingtheuseofpulse-oximeterderivedplethysmographyasaless-invasivealternativetoSPVorPPV(e.g.Pizov)作为CVP预测容量反应能力的替代指标，其他

技术[（包括每博量变异度（SVV）以及由胸内血容量指数(ITBV）演变而来的PICCO）]正在研发中，但其性能不如PPV或SPV。Systolicpressurevariationisusefulasaguidetothemanagementofthepatientinshockinanothe

rway:patientswithminimalornovariationinthebloodpressureandpulsepressureareveryunlikelytorespondtovolumeadministration.另一方面，对休克患者进行管理

时，收缩压变异度为一个非常有用的指标：患者血压和脉压出现极小或无变异时，几乎不可能对容量治疗作出反应。Theinitialeffortstoresuscitatesuchpatientsshouldthereforebedirectedatpharmacologicorme

chanicalinterventions,whicharemuchmorelikelytobeeffective.Becausethisstrategyminimizestheunnecessaryadministrationoffluidtocriticallyillpatients

,itmayimproveoutcomes.因此，对此类患者进行复苏时，最初的努力应着眼于使用药物或机械方法干预，这样或许会更有效。由于该方案最大限度的减少了对危重患者实施的不必要的液体治疗，因而可能会改善

预后。Whatdoesn’tfit?Mostpatientswithhypovolemicshock,LVshock,andsepsisrespondtoappropriatetherapy.Failuretoresponds

houldraiseredflags,anddriveanevaluationforobstructiveshock.大多数低血容量性休克、LV休克（左心室相关性休克）以及败血症患者对恰当的治疗均有反应。对于无反应者，应该停止治疗并评估是否发生阻塞性休克。Ob

structiveshockisshockcausedbyanobstructiontovenousreturn.Obstructionstovenousreturnareofteninsidious.Whilevolumeresuscit

ationandtherapywithvasoactivesmightproduceatransientminorimprovementinthecirculation,thedefinitivetreatmentconsistsofrelievingtheobstruct

ionifthisispossible.阻塞性休克由静脉回心受阻引起。静脉回心受阻一般较为隐匿。虽然容量复苏和应用血管活性药物治疗可能会产生短暂轻微的循环改善，但如果可能，恰当的治疗应当包括减轻静脉回心阻力。Caus

esofObstructiveShock(ObstructionstoVenousReturn)-pericardialeffusion-restrictivepericardium-tensionpneumothorax-highlevelsofPEEPorin

trinsicPEEP-massivepleuraleffusion-abdominaltamponade-venousocclusion(clot,air,tumor,pregnancy)-atrialocclusion(clot,air,tumor)阻塞性休克的病因（静脉回心受阻）

：-心包积液-心包缩窄-高PEEP或固定PEEP-大量胸腔积液-腹腔填塞-静脉闭塞（血块、气体、肿物、羊水）-动脉闭塞（血块、气体、肿物）Interestingly,asagroup,obstructionstovenousreturnprodu

cethekindsofvariationsinpulsepressuredescribedabove(Magder2004,2005).Morerecentclinicalstudieshavereportedthatrightventricularshockcanalsoproduc

eanincreaseinSPVorPPVthatisnotresponsivetofluidadministration(Mahjoud).有趣的是，作为一个整体，静脉回心阻力可产生上述几类脉搏压力变异。因此，当患者存在明显的脉搏压力变异（和较高的CVP）、对液体治疗无反应

时，有经验的医师应该想到应用静脉回心受阻来解释该情况。Hence,whenapatientwithsignificantpulsepressurevariation(andahigherCVP)failstorespondtofluidadministration,thesa

pientpractitionershouldentertainthepossibilityofrightventricularshockoranobstructiontovenousreturnastheexplanation.对此类患者进行的快速评估包括体格检查，尤其应该密切注意心音的

特点、胸廓的对称性和活动度以及腹壁紧张度。Theexpeditiousevaluationofsuchpatientsincludesaphysicalexamwithcarefulattentiontothecharacterofthehearttones,chestwallsymmetr

yandexcursion,andabdominalwalltension.Inpatientswithtenseordistendedabdominalwalls,transducingabladderpressureisveryhelpfulincompletin

gtheevaluationforabdominaltamponade.当患者出现腹壁紧张或腹胀时，转导膀胱压力有助于完成腹腔填塞评估。对于行机械通气的患者，应该使用自动呼末正压通气评估呼气流量波形。Inmechanicallyventilatedpatients,t

heexpiratoryflowwaveformshouldbeevaluatedforauto-PEEP.Inmostinstances,astatportablechestradiograph,trans-thoracicechoc

ardiogram,andthemeasurementofabladderpressurewillbesufficienttocompletetheevaluationofapatientwithrefractoryshock.对于行机械通气的患者，应该使用自动呼末正压通气评估呼气

流量波形。在大多数情况下，一幅床旁胸片、超声心动图和膀胱压测量仪足以完成对顽固性休克患者的评估。ReconciliationofCentralVenousPressuresandDynamicIndicatorsThefollowing2x2tableisintende

dtoaidpractitionersintheirassessmentofpatientswithhypotension:Thankyou!UnderstandingClinicalHemodynamics